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TPH Risk Evaluation at Petroleum-Contaminated Sites
Navigating this Website
2 Introduction Overview
2.1 Issues Unique to TPH
2.2 Applicability of Guidance
2.3 Background of Current Approaches
2.4 TPH Risk Characterization Framework
3 Regulatory Framework
3 Regulatory Framework Overview
3.1 History of TPH Regulation
3.2 What is the Legal Basis for Risk-Based Closure of Petroleum Sites?
3.3 TPH-Specific Regulatory Challenges
3.4 TPH-Specific Regulatory Tools
4 TPH Fundamentals
4 TPH Fundamentals Overview
4.1 Petroleum Chemistry and Refining
4.2 Physical and Chemical Properties of Petroleum Constituents, TPH Carbon Ranges (Fractions), and Metabolites
4.3 Properties of Aliphatic and Aromatic Hydrocarbon Fractions
4.4 Alterations of Petroleum Mixtures in the Environment Through Weathering Processes
4.5 Definition of "TPH" in Environmental Media in Risk Assessment
5 Conceptual Site Models
5 Conceptual Site Models Overview
5.1 Source Identification (Qualitative CSM)
5.2 Source Area Characterization, Extent, Distribution (Source Definition)
5.3 Fate, Transport, and Attenuation Mechanisms (Pathway Definition)
5.4 Points of Exposure (Receptor Definition)
5.5 TPH Target Levels
5.6 Compiling a CSM
5.7 TPH Data Collection Plan
5.8 Field Sampling Methods and Handling Procedures
5.9 TPH Analytical Methods
5.10 Silica Gel Cleanup Method
5.11 Reporting, Data Qualification, and Chromatograms
5.12 Data Usability, Interpretation, and Implications
6 Human Health Risk
6 Human Health Risk Overview
6.2 Exposure Assessment
6.3 Direct Contact with TPH
6.4 Soil to Ambient Air Exposure to TPH (Volatiles and Particulates)
6.5 Leaching from Soil to Groundwater
6.6 Exposure to Groundwater/Surface Water
6.7 Exposure to Air
6.9 Toxicity Assessment
6.10 Evaluating Toxicity of Polar Metabolites
6.11 Toxicity Considerations for Different Exposure Rates
6.12 Risk Characterization
7 Ecological Risk Assessment
7 Ecological Risk Assessment Overview
7.1 ERA Process for TPH
7.2 Current National and North American TPH ERA Practice
7.5 Risk Characterization
8 Risk Calculators
8 Risk Calculators Overview
8.1 Calculating TPH Risk
8.2 Electronic TPH Risk Calculators
9 TPH Special Considerations
9 TPH Special Considerations Overview
9.1 Special Factors
9.2 Emergency Conditions
9.3 Worker Exposure and Safety
9.4 Managing Open and Reopened TPH-Contaminated Sites
9.5 Estimating TPH Fractions
9.6 Managing the Presence of TPH Breakdown Products/Metabolites
9.7 Remedial Action and Institutional Controls
9.8 Common Mistakes and Lessons Learned
10 Stakeholder Concerns
10 Stakeholder Concerns Overview
10.1 Community Engagement Plans
10.2 Tools for Effective Community Engagement
10.3 Risk Communication
10.4 Communicating Risk Associated with TPH
10.5 VOCs in Commonly Used Products
10.6 Public Notification of Sampling
10.7 TPH Concepts Explained
11 TPH Risk Case Studies
Appendix A. Fact Sheets
A.1 Definition of TPH—Don't Let the Name Fool You
A.2 TPH Analytical Methods
A.3 Silica Gel Cleanup (SGC)
A.4 Chemistry of Weathering Processes
A.5 Chromatograms: A Wealth of Information
A.6 TPH Fractionation Methods
Appendix B. Risk Evaluation Reference Tool
Appendix C. States Survey
Appendix D. Field Screening Methods
This section discusses the evaluation of TPH at petroleum-contaminated sites to characterize human health risks. It also presents a discussion of the varying approaches to evaluating health risks for TPH, how the approaches need to be modified to address specific exposure routes, and how evaluation of metabolites and degradation products can be addressed. The discussion of how TPH risk assessment differs from the risk assessment of other chemicals and the variations in approaches to TPH risk assessment will serve as a basis for understanding and performing TPH risk assessment at individual petroleum release sites and can provide a basis for developing or revising regulatory approaches to human health risk assessment for TPH.
Several methods are available for evaluating the human health risks associated with petroleum releases. One approach is estimating health risks for individual hydrocarbon compounds (e.g., BTEX, PAHs), and summing the risks and hazard indices estimated for each of the hydrocarbon chemicals evaluated. Such evaluations often address nonhydrocarbon components of the original mixture (e.g., additives such as MTBE) and help to estimate the cancer risk because TPH is not considered to be a carcinogen. These chemicals frequently make up a very small fraction of the bulk of the petroleum compounds for a release, which leaves uncertainty as to the health risk of the remaining mass. To address this issue, methods have been developed over the past twenty years to more precisely quantify TPH in terms of a small number of targeted, aromatic and aliphatic carbon ranges. Representative physiochemical constants and toxicity factors are then assigned to carbon ranges. This allows the data to be considered in standard risk assessments and related models in the same manner as is done for individual chemicals. Evaluating the human health risks associated with petroleum releases is the subject of ongoing research.
There are unique aspects of TPH that pose challenges when performing the risk assessment and interpreting the results. Three of the most important aspects of TPH that must be considered include the complex and variable nature of petroleum releases, the fact that the composition of any given released petroleum mixture can change substantially as a result of "weathering," and the potentially substantial and selective partitioning of mixture components as they move from one environmental media into another. Over the last several years, regulatory concentration limits for TPH have evolved from being predominantly based on nuisance (e.g., odor, discoloration) to being increasingly based on human health protection Tomlinson and Ruby 2016. However, aesthetic considerations in addition to risk may need to be factored into environmental management decisions (see Case Studies).
Disturbance of heavily contaminated soil or groundwater during remediation and construction activities can also lead to the temporary but significant emissions of petroleum vapors and short-term risk to workers and occupants of neighboring properties. However, health effects are normally transient (temporary), and may quickly diminish once exposure is ceased. Methods to predict and manage shorter term risks are qualitatively discussed in Section 9 of this document.
Figure 6‑1. Contamination life cycle.
Petroleum mixtures reported as TPH can consist of thousands of individual compounds, and mixtures reported as a specific petroleum product (e.g., gasoline) can have significantly different molecular compositions. Even greater variability can be expected for petroleum releases of crude or residual oil, and it is not unusual to have more than one refined product present at a release site. Not only is the originally released material at virtually all petroleum release sites a complex mixture of hundreds of hydrocarbons, but the composition of nominally similar materials (i.e., gasoline, crude oil, etc.) can differ in ways that would affect the environmental mobility and toxicity of the mixture (see Petroleum Chemistry and Refining).
Once released into the environment, chemical and biological processes will begin changing the composition of the originally released material. Although such "weathering" of released petroleum has long been recognized, the need to explicitly consider the chemical and biological degradation products in a human health risk assessment is a relatively recent development.
Most or virtually all of the mass of degradation products typically results from the oxidation of hydrocarbons. Accordingly, the degradation products tend to be dominated by polar compounds that have different chemical properties and behaviors in the environment and different toxic properties than their parent hydrocarbons. These degradation products are commonly referred to as metabolites, and largely for the sake of convenience, that term is used in the text below. Consideration of the metabolites is important because, while they are not necessarily present at all sites, they can make up the dominant mass of the residue from a petroleum release during specific phases of the lifecycle of the release (see Alterations of Petroleum Mixtures in the Environment through Weathering Processes).
A consideration in evaluating health risk is the fact that various constituents of TPH will tend to differentially partition from the main mass of a fresh or weathered release if they move from one environmental media to another. Surface water or groundwater affected by a petroleum release would be enriched in the more water-soluble constituents relative to the mixture that may have been released to soil, for example. Vapor intrusion is only likely to involve the more volatile constituents. Plant or fish uptake would also involve selective enrichment.
Some environmental media may not be amenable to TPH analyses. Concerns about health risks posed by accumulation of chemicals associated with a petroleum release in irrigated crops or fish or animal tissue could not be addressed by chemical analyses for TPH because the petroleum-related materials could not be distinguished from the plant or animal tissue. The risk assessor would need to decide on a set of appropriate indicator chemicals for such evaluations.
Key factors to consider when assessing TPH exposures include the wide variation in physical and chemical properties of the mixture and potential exposure impacts as the mixture partitions between different environmental phases. Estimating exposure point concentrations in different media requires characterizing the TPH fractions (if a fraction-based approach is being used), individual chemicals, or both, that will be the basis of an evaluation. Any site-specific needs would also need to be considered, as would any applicable regulatory requirements or guidelines. Site-specific needs may also include consideration of acute effects and aesthetics (e.g., odor or visual impacts) (see Examination of Risk-Based Screening Values ITRC 2005, and Use of Risk Assessment in Management of Contaminated Sites ITRC 2008).
Appropriate sampling and analysis methods for TPH in soil are presented in Section 5. The sampling methods need to consider the type of petroleum product, whether the product is new or weathered, and other environmental conditions (e.g., heat) that could affect the selection of complete exposure pathways or the quantification of exposure.
Direct contact with chemicals in soil typically involves ingestion, dermal contact, and inhalation of vapors or particulates USEPA 2017c. To evaluate these potential exposure pathways for a TPH risk assessment, the composition of the TPH mixture should be considered. For the ingestion and dermal contact pathways, bioavailability of TPH compounds may be considered. Although bioavailability methods for PAHs are not yet defined, the potential for refining the human health risk assessment (HHRA) may be considered. The use of bioavailability in risk assessment is discussed in the ITRC's Bioavailability of Contaminants in Soil (BCS) document. Though the BCS document does not specifically discuss TPH, it presents methods for evaluating oral and dermal PAH bioavailability that can be applicable to TPH if individual PAHs are included in the HHRA. The BCS also discusses the considerations (e.g., PAH source and concentration, or skin models) for validating these methods and identifying other methods that can predict bioavailability with higher certainty.
For some TPH mixtures containing PAHs, dermal contact may contribute to the overall cancer risk USEPA 2018c. However, caution must be used when considering PAH dermal risk assessment because the EPA has not finished evaluating dermal toxicity data to develop appropriate dermal cancer toxicity values. In addition, methods have not been developed for the evaluation of direct contact with petroleum products based on total TPH (DRO/GRO) or TPH fractions. Currently, EPA has provided chemical-specific dermal absorption efficiency factors (referred to as AEd) for some TPH volatiles, and semivolatiles are assigned a default value of 10% USEPA 2004. EPA is continuously updating the dermal absorption values as information becomes available USEPA 2018c.
Soil to ambient air inhalation exposure to TPH volatile components is commonly evaluated for individual TPH compounds (e.g., BTEXN and PAHs) using mathematical models, e.g., the Jury model Jury, Farmer, and Spencer. 1984, which predicts chemical transport and requires single-chemical data input (HLC, Kow, Koc), and dispersion models (AERMOD), which predict subsequent dispersion of vapors in ambient air. The Jury model does not accommodate mixtures USEPA 1996, 2002. However, where physiochemical property data and inhalation toxicity values are available for individual TPH fractions MADEP 2003, the Jury model can be used to estimate the flux for specified carbon ranges and the risk can be evaluated for specific carbon ranges. The risk to exposure to total (bulk) TPH can also be evaluated using weighted averages of the estimated risk for individual carbon fractions Brewer et al. 2013. It should be noted that exposure evaluation based on the Jury modeled flux cannot be used for evaluating soils when the TPH mixture is present as a free-phase product (saturated concentration) USEPA 2002.
Alternative methods for evaluating ambient air exposure to individual carbon ranges in soil that are used in many states include soil vapor and direct flux measurements. Direct flux measurements using flux chamber sampling are combined with dispersion modeling to estimate air concentrations that are then compared to ambient air screening levels of individual compounds or petroleum hydrocarbon mixtures USEPA 2002; ITRC 2008.
For particulate emissions of TPH in soil, the particulate emission factor (PEF) can be used, which is applicable to all types of TPH compounds, because it is not chemical-specific. At sites with increased soil-based activities (e.g., construction sites), the particulate emissions due to vehicular traffic on unpaved roads should be considered in the PEF derivation USEPA 2002; ITRC 2008.
As discussed in Sections 5.3 and 5.4, physiochemical constants assigned to individual carbon ranges can be used in soil leaching models to derive leaching-based screening levels or predict groundwater concentrations resulting from soil migration to groundwater in the same manner as carried out for individual compounds. To estimate the potential for TPH mixtures to leach to groundwater, it is important to incorporate appropriate chemical-specific values (HLC, Koc) specific to each TPH fraction USEPA 1996. The accuracy of commonly used leaching models is dependent on site-specific parameters and adequate knowledge of the physio-chemical properties of the contaminant(s). This can be particularly challenging for complex mixtures such as TPH. Further research regarding this subject is required.
In general, the potential for leaching will be greatest for the <C9 aromatics and other compounds with high aqueous solubility (e.g., TPH polar metabolites). The leaching potential of polar metabolites has yet to be evaluated. Identifying and incorporating mole fractions of the petroleum hydrocarbon mixture into the leaching evaluation is essential. Failure to include TPH fractions in this pathway's evaluation can result in inaccurate estimates of release from soil and transport into the water phase, which may be amplified when (1) the TPH mixture is present as LNAPL; or (2) the petroleum hydrocarbon mixture contains heavier oils (higher molecular weight compounds) with negligible aqueous solubility.
Analytical tools used to empirically determine TPH leaching potential include the Synthetic Precipitation Leaching Procedure (SPLP) analysis (EPA SW-846 Method 1312) and the SPLP Batch Test Leaching Model, which both use a slightly acidic extraction fluid to estimate leachate concentrations in situ.
If LNAPL is present in soil, leachate analyses may inaccurately predict the leaching potential of the TPH mixture due to direct partitioning of nonsorbed droplets into the leachate solution. One option to help minimize this uncertainty is the use of soil column leaching tests. See Case Studies 1, 2, 3, and 5 for more information. Note that polar metabolites can form in the vadose zone as hydrocarbons migrate.
Petroleum spills and leaks to land surface or surface water bodies can result in elevated concentrations of TPH and TPH-related metabolites in groundwater or surface water via the migration of free product or leaching. Short-term (subchronic) and long-term (chronic) exposures to TPH can occur via contact with groundwater used as a potable water supply (e.g., private drinking water wells) and other water uses (e.g., swimming pools). TPH presence in groundwater can be detected by affected receptor populations from the distinctive taste, discoloration, and odor characteristic of some of the individual TPH components (e.g., benzene).
Due in part to the complexity of TPH components themselves, determining their potential exposures becomes a challenge. The exposure point concentration is heavily dependent upon the specific analytical method details and requirements, which vary from state to state. Over the years, the selection of surrogate or indicator compounds (or a combination of compounds) to represent TPH has become a common remedy to this problem.
Exposure to surface water may be lower than that of groundwater due to generally less frequent contact and shorter term average exposures or shorter average exposure durations. In instances where TPH-contaminated groundwater may be discharging to a surface water body, some states allow use of surface water modeling and site-specific dilution factors for high flow, lentic systems to predict TPH concentrations in surface water. Other state agencies, such as MADEP, have issued policy in the form of a support document on the VPH/EPH approach to modeling MADEP 2002b.
A number of challenges exist when investigating and addressing the risk from exposure to fuel-related chemicals in surface water bodies (e.g., rivers, creeks, sensitive wetlands, drainage canals, ditches, roadway runoff, etc.) that may be flowing or discharging to other locations. One issue is the presence of competing sources; the collection of background data can be critical in eliminating these other sources. In addition, some surface waters (e.g., small wetlands) may have normally high background concentrations of nonpetroleum-related compounds detectable in the TPH analysis that must be distinguished from potential sources in question. High background levels may come from either naturally occurring sources (e.g., natural seeps) or anthropogenic sources. Environmental forensics could help in making this distinction between the footprint of TPH in background material and TPH from a particular source.
6.7.1 Outdoor (Ambient Air)
Inhalation toxicity factors assigned to individual carbon ranges can be used to develop risk-based screening levels for ambient air and/or directly quantify human health risk in the manner as done for individual compounds. Exposure assessment of TPH and TPH-related compounds in ambient air resulting from emissions from contaminated soils can be complicated and, in many cases, irresolvable in the presence of multiple (non-site-related) sources of TPH in ambient air, including fueling stations, auto exhaust, cleaning fluids, and other uncertain and nonpoint sources. Because of these potentially confounding sources, it may be important to include sufficient background (or reference) locations in any outdoor air TPH sampling program, if ambient air exposure is to be measured directly. The alternative to direct measurement, modeling of ambient air concentrations from soil, is discussed in Section 6.4
Due to the limited studies, bioassays, and heightened uncertainty in the bioaccumulation and biomagnification of TPH in aquatic and terrestrial ecosystems, these evaluations are typically not recommended for use in risk management decision making. Instead, individual chemicals of concern become the focus. In general, the lower molecular weight aliphatics and aromatics do not bioaccumulate, but there is some evidence that aquatic and terrestrial organisms do bioaccumulate some TPH constituents, particularly PAHs Farrington et al. 1982. However, depuration does occur if the source of the contamination is removed Cox et al. 1975; Williams et al. 1989.
Some of the difficulties associated with trying to evaluate the food chain uptake pathway include the following:
terrestrial plants and aquatic algae can metabolize hydrocarbons, making it difficult to decipher whether the hydrocarbons in the soil will actually be in the plants from the soil Eisler 2000
plants and animal tissues are made up of organic chemicals, which will often themselves report as TPH if analyzed Hoffman et al. 2003
models can attempt to predict only what could actually occur (e.g., use of food chain models that estimate uptake may not truly reflect what is actually happening). Similar arguments can be applied to the animal meat uptake pathway (see Ecological Risk Assessment).
6.8.1 Plant Consumption
Humans may be indirectly exposed to TPH via plant ingestion in instances where food crops are irrigated with water containing TPH, for example. However, because TPH analytical methods would extract plant material as well as any petroleum components, they cannot be used to analyze for petroleum residues in plants. Risk assessment of TPH in plant material must rely on chemicals selected to match the surrogate chemicals of potential concern in the soil or irrigation water to which the food crops may have otherwise been exposed. Further information on plant uptake of TPH and TPH toxicity in plants is provided in Ecological Risk Assessment.
6.8.2 Meat and Milk Consumption
Human exposure to TPH may also occur through the ingestion of livestock (e.g., contaminated meat) or consumption of milk from animals that may graze on TPH impacted soil or ingest TPH-contaminated water as drinking water. As with plant consumption, TPH analytical methods are not applicable to meat or milk. Indicator chemicals relevant to the spilled petroleum that would be expected to partition into and possibly accumulate in the edible portions of the target species need to be selected.
6.8.3 Fish and Shellfish Consumption
Consumption of fish and other aquatic organisms following a fuel release or crude oil spill into surface water is an exposure scenario that often needs to be addressed. Fisheries may be closed as a preventive measure following a spill, and a human health risk assessment may be required before the fishery can be reopened. As with plant and other animal tissues, predicting or measuring the uptake of hydrocarbons into fish tissue from a specific petroleum release is challenging. Chemical analysis of fish and shellfish using fractionation or a bulk TPH method is not practical because fish oil and other tissue components will be detected as TPH. Rather, indicator chemicals relevant to the spilled material that would be expected to partition into fish and shellfish need to be selected Yender et al. 2002; CAOEHHA 2015. In addition to a human health risk assessment, it may be necessary or desirable to perform a sensory evaluation (i.e., testing for off-flavors and off-odors) of the fish and shellfish in support of a decision to reopen a fishery Reilly and York 2001. Although analytical instrumentation is becoming more sophisticated, these instruments are chemical detectors only and are incapable of making any sensory judgment on odor or flavor NOAA 2001.
Equally important as exposure assessment in risk evaluation is the understanding of toxicity. The section below presents some focused background points for the discussion of the toxicity assessment of TPH along with a discussion of the basic approaches that have been taken to the toxicity assessment of TPH. The challenges and proposed approaches to evaluating the toxicity of petroleum metabolites are also discussed.
6.9.1 Background and Overview of TPH Toxicity Assessment Methods
There are a few basic approaches to toxicity assessment for TPH. Each approach addresses the challenges posed by the assessment of TPH toxicity in a different way. The best approach to apply in any given situation, however, is often a hybrid approach, particularly if multiple exposure routes need to be addressed.
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The most basic challenge to evaluating the toxicity of TPH in a human health risk assessment is the fact that any given TPH mixture can consist of hundreds to thousands of different compounds. Even if it were possible to measure the concentration of each compound, toxicity data are not available for each one. Another challenge is the fact that petroleum mixtures released to the environment will change as they weather. Even if there are results from toxicity testing of a fresh petroleum product, weathering will change the composition of the mixture to such an extent that toxicity results from fresh product cannot be extrapolated to weathered product. In addition, there will typically be further change of mixture composition as a result of partitioning, if the released petroleum moves from one environmental media into another.
A few additional factors to keep in mind when selecting an approach for estimating the toxicity of a TPH mixture and when interpreting the results include: (1) the compounds making up any specific mixture analyzed as TPH can include hydrocarbons as well as polar compounds; (2) the mixture reported as TPH can include naturally occurring (e.g., humic acids) and anthropogenic substances (e.g., PCBs, chlorinated solvents, phthalates) that are not derived from released petroleum; and (3) the compounds detected and reported as TPH will depend on the specific TPH analytical method used (see TPH Fundamentals).
Two foundational concepts applicable to all health risk assessments that are important in evaluating the toxicity of TPH are the assumption of additivity of dose or effect and the closely related risk assessment policy generally referred to as "the mixtures policy." The USEPA addresses the additivity assumption in their Provisional Peer-Reviewed Toxicity Values (PPRTV) document for Complex Mixtures of Aliphatic and Aromatic Hydrocarbons USEPA 2009d, and they recommend assuming additivity of effects of hydrocarbon fractions comprising TPH. The Agency for Toxic Substances and Disease Registry ATSDR 1999 also recommended assuming additivity when evaluating environmental levels of TPH.
As shown below, toxicity testing of certain highly refined hydrocarbon mixtures with narrow carbon size ranges (e.g., white mineral oil) has been applied to the toxicity of TPH fractions found in the environment with similar molecular size ranges. The assumption underlying this extrapolation is that the mixture of the narrow range of hydrocarbons subjected to toxicity testing is similar in composition and toxicity to the mixture of chemicals comprising the corresponding TPH fraction. Accordingly, toxicity test results from the similar mixture are presumed to be a reliable estimate of the particular TPH fraction.
Even though TPH is itself a mixture, it is present at contaminated sites among a few or many additional COPCs. Where aggregate risk evaluations of noncancer health risks for TPH and other COPCs are allowed, the Hazard Index (HI) calculated for TPH can simply be added to the HI calculated for other COPCs. For the evaluation of cancer risk, the typical approach taken for petroleum release sites is the same approach as is used for any other site risk assessment (i.e., TPH is not generally considered to be a carcinogen so the lifetime incremental cancer risk is estimated for individual carcinogenic chemicals and summed).
The discussion of toxicity assessment for TPH presented below focuses on methods for evaluating chronic exposures, but acute exposure can also be a concern for TPH releases. Information relevant to addressing acute exposures to the public and in the workplace has been provided most directly by the ATSDR, the Occupational Safety and Health Administration (OSHA), and the National Institute for Occupational Safety and Health (NIOSH).
To address the concerns that community members and other stakeholders may have about acute toxicity of the refined petroleum products, ATSDR 1996 offers a frequently asked questions (FAQ) section for automotive gasoline, stating that inhaling or ingesting large amounts of gasoline is irritating to the lungs or stomach lining, respectively. Breathing or swallowing large amounts of gasoline may cause harmful effects on the nervous system, ranging from serious effects like coma or inability to breathe, to less serious effects like dizziness and headaches. Comments on OSHA's 1989 Final Rule on Air Contaminants Project may be valuable for addressing both public and workplace exposures, and they suggest that people exposed to 160–270 ppm of gasoline for several hours may experience eye and throat irritation, but no symptoms of narcosis OSHA 1989. ATSDR 2017 also offers toxicological information regarding jet fuels (JP-5, JP-8, and jet A fuels).
Though little is known about its effects on human health, ATSDR 2017 notes that humans who have ingested kerosene, a fuel similar in composition to the jet fuels, reported harmful effects on the respiratory tract (cough and difficulty breathing), gastrointestinal tract (abdominal pain and vomiting), and nervous system (drowsiness, restlessness, and convulsions). Given the variable nature of gasoline composition, OSHA does not have occupational exposure limits for gasoline. However, OSHA 2012 has set a time-weighted average permissible exposure limit for petroleum distillates (naphtha) at 500 ppm (2,000 mg/m3).
6.9.2 Approaches to TPH Toxicity Assessment
Recognizing the challenges posed by the need to characterize the toxicity of TPH, a variety of approaches have been developed and are currently in use. The oldest approaches rely primarily on an evaluation of indicator chemicals, which may or may not have been accompanied by an evaluation for various whole product fractions (e.g., gasoline range total petroleum hydrocarbons, diesel range petroleum hydrocarbons, or residual range total petroleum hydrocarbons). More recently, a variation of the indicator chemical approach has evolved, in which the bulk TPH mixture is divided into its aliphatic and aromatic components and then into discrete carbon ranges smaller than that of a typical petroleum product. The potential toxicity of these fractions is then used to evaluate risk, generally in conjunction with an evaluation of selected individual hydrocarbon chemicals. These general approaches are illustrated in Figure 6-2, which is from the TPHCWG 1999.
Figure 6‑2. TPH toxicity assessment methods TPHCWG 1999.
The three basic approaches to toxicity assessment of TPH are described below, including the indicator chemical approach, the fractionation approach, and whole product approach. Although each of these basic approaches are distinct, they are most often used in conjunction with each other (see TPH Fundamentals).
6.9.2.1 Indicator Chemical Method
One approach to evaluating health risks for petroleum hydrocarbon mixtures is to rely on indicator chemicals USEPA 1986, 1989, 2000c. Local guidance can vary for the indicator chemicals to be used for either cancer or noncancer health risks. The results of the States Survey show the indicator chemicals recommended by several different states.
The assumption underlying the use of the indicator chemical approach is that the indicator chemicals represent most of the mixture's toxicity, and therefore, the health risk of the entire mixture can be estimated to a reasonable degree of certainty by relying on the health risks estimated for the indicator chemicals USEPA 1989. Contrary to this assumption is the fact that the indicator chemicals often make up a small fraction of the mass of the TPH range to which they are applied. On the other hand, the indicator chemicals are thought to be more toxic than the rest of the chemicals in the mixture. Concern over the validity of the indicator chemical approach is most often raised for sites with weathered releases of products where the indicator chemicals used for the released product(s) may not be present at detectable levels, but at which residual hydrocarbons are noticeably or measurably present. In such cases, reliance on indicator chemicals alone can cause health risks to be underestimated or can leave questions about the adequacy of an evaluation relying solely on indicator chemicals.
The need to evaluate health risks for TPH residues in cases where the evaluation of indicator chemicals alone results in very low or zero health risk can be driven by regulatory requirements, community stakeholders, the need to adequately characterize site contamination, or by risk communication needs, particularly in cases where the indicator chemicals may be perceived to be underestimating risk. In such cases, reliance on the indicator chemicals alone can cause exposure and risk to be underestimated, particularly if unresolved hydrocarbon mixture and/or polar metabolites make up a large fraction of the mass of material present. Some states indicated in the States Survey that they believe an indicator chemical only approach adequately characterizes health risks. The survey did not ask the states for data or other information to support this conclusion and none were available at the time this document was published.
6.9.2.2 Fractionation Methods
Under the fractionation approach TPH is divided into aromatic and aliphatic compounds, and the aromatic and aliphatic compounds are further divided into several defined carbon ranges. The various fractions were originally divided into groups that would have similar fate and transport properties MADEP 1994, 2002a; TPHCWG 1997a. Massachusetts MADEP 1994, British Columbia BCMoE 1995, and the TPHCWG 1997a were the earliest groups to develop and recommend use of the fractionation approach. The ATSDR 1999, USEPA 2009d, and several states have also adopted versions of the fractionation approach. Examples of fractions and the toxicity factors assigned to them are shown below in Tables 6-1 and 6-2. Variations in the fractionation approach include different divisions of the fractions to be addressed and different approaches to the assignment of a toxicity value to each fraction (e.g., assign the toxicity of a constituent typical of the toxicity of the fraction or assign the toxicity of the most toxic constituent).
Table 6‑1. Summary of noncancer oral toxicity values (mg/kg-day)
TPHCWG 1997c; MADEP 2003; USEPA 2009d; TCEQ 2010
View Table 6-1 in Adobe PDF format.
Table 6‑2. Summary of noncancer inhalation toxicity values (mg/m3)
As noted by the TPHCWG 1997a, the fractionation approach was intended to supplement the indicator chemical approach to evaluating TPH. It provides a way to address the situation noted above, in which indicator chemicals are not present at detectable levels, yet petroleum residues requiring evaluation are present. The fractionation approach also has the advantage of flexibility, as it can be applied to any TPH mixture found in the environment, and it results in a greater characterization of the site and risk posed by TPH.
When performing human health risk assessment using the indicator or individual chemical approach, each TPH fraction is treated as though it were a separate COPC. Hazard quotients (HQs) for individual TPH fractions are added to HQs for other TPH fractions and to HQs for TPH indicator or individual chemicals to estimate an HI for TPH.
When performing this calculation, it is important to subtract the concentration of individual chemicals from the concentration for the TPH fraction that would have included the individual chemicals. This exercise is to avoid double counting the concentration of TPH and individual chemicals. Depending on how the TPH fractions are defined, these chemicals may account for most, if not all, of a fraction. For example, BTEX could add up to all of the small aromatic hydrocarbon range, C6–C8, in the USEPA 2009d fractionation approach. This should be done only where the TPH and individual chemicals have been analyzed using the same method. Many labs will perform this subtraction for you.
Although the organizations mentioned above have adopted or recommended TPH fractionation as the preferred way of addressing human health risk assessment for TPH, there are differences in the carbon ranges and toxicity factors recommended by these organizations for each carbon range (see Table 6-1). Differences in the recommended toxicity factors stem, in part, from the use of different approaches to selecting the toxicity factors for each TPH fraction.
The approaches used include:
use of toxicity test results from a hydrocarbon mixture similar to a particular aliphatic or aromatic fraction
selection of toxicity factors for one or more indicator chemicals to represent the toxicity of the mixture making up a fraction
a hybrid approach, in which both individual chemicals and toxicity test results from a similar mixture are presumed to be a reliable estimate of a particular TPH fraction USEPA 2009d. A variety of toxicity factors have been applied to similar fractions by the various organizations that have recommended fractionation approaches.
Differences in recommended toxicity factors are attributable to a variety of factors, including:
availability of new toxicity studies since the approach was first developed
updated toxicity evaluation methods
better understanding of the toxicity of the TPH components
procedural and policy differences between the various organizations in selecting toxicity values
changes over time in the procedures and policies related to setting toxicity limits
differences in judgment regarding the most appropriate test results or critical study and the application of uncertainty factors
The USEPA 2009d noted that the toxicity factors they have developed for the six aliphatic and aromatic hydrocarbon fractions are Provisional Peer-Reviewed Toxicity Values (PPRTVs), which means they have been developed using the similar methods, data sources, and guidance as are used for developing toxicity factors for the USEPA Integrated Risk Information System (IRIS) Program. PPRTVs are developed specifically for use in the Superfund Program and receive peer review by two USEPA scientists and their independently selected scientific experts. They are not subjected to the same multiprogram peer review to which IRIS values are subjected USEPA 2009d.
As shown in Table 6-1, the toxicity factors used to develop the USEPA Regional Screening Levels (RSLs) for TPH include PPRTVs for TPH fractions, as well as IRIS values selected as surrogate toxicity factors for TPH fractions USEPA 2018c. For at least some carbon range fractions, the values used in the derivation of the RSLs are more conservative than the PPRTVs recommended for the same fraction. Although no specific explanation for the difference is offered in the RSL documentation, the RSL Work Group selected the most toxic individual chemical as the surrogate for the toxicity of specific hydrocarbon fractions. Because the RSLs are intended for use as screening values, it would be consistent with standard risk assessment procedures to use less conservative toxicity factors, such as PPRTVs, for a baseline risk assessment or for the calculation of risk-based cleanup values, for example.
Although cancer risk for petroleum releases are almost always based on estimating and summing cancer risk for carcinogenic individual chemicals, the USEPA 2009d did develop inhalation unit risk (IUR) factors for their low carbon range aliphatic (C5–C8, EC5–EC8) and medium carbon range aliphatic (C9–C18, EC>8–EC16) TPH fractions as part of its PPRTVs for Complex Mixtures of Aliphatic and Aromatic Hydrocarbons. USEPA characterizes these IUR factors as "screening level" values that may be useful in "certain situations" and recommends reporting the fraction of any estimated cancer risk that is attributable to these more uncertain toxicity factors. As discussed in FAQ#48 in the RSL USEPA 2018e documentation, the RSL Work Group elected not to use the screening level IURs in the derivation of the RSLs because they felt that combining cancer risks based on these TPH fractions and individual chemicals would be overly protective.
As new toxicity data become available, it will be necessary to consider updating the toxicity factors assigned to the various TPH fractions, and the policies used by one agency to select a toxicity factor may not be appropriate for another agency. Agencies setting up new programs for evaluating TPH based on TPH fractions may want to consider the availability of toxicity data more recent than the last toxicity factors adopted by another agency and may want to evaluate the appropriateness of the policies underlying another agency's toxicity factors. For example, a report sponsored by the American Petroleum Institute ToxStrategies 2016 noted that newer toxicity studies than those relied on by the USEPA 2009d were available, and that the size of the uncertainty factors used in the derivation of some toxicity factors by USEPA 2009d was larger than those applied to the same toxicity studies by other organizations.
6.9.2.3 Whole Product Method
Under the whole product approach, a single toxicity factor is assigned to a whole petroleum product, such as gasoline, diesel fuel, jet fuel, bunker fuel, crude oil, etc. A variety of approaches may be used to assign the toxicity factor for the product. For example, toxicity test results from testing a whole product might be used. The primary drawback to this approach as discussed above is the fact that the composition and toxicity of the product will change as it weathers and could only be applied to fresh releases. Another important consideration is the higher degree of variability in the unrefined petroleum materials (e.g., bunker fuel and crude oil), which would pose a great deal of uncertainty in extrapolating toxicity test results from one tested product to others. In addition, test results are not available for all of the whole petroleum products.
Because whole product TPH analytical results are frequently a significant portion of, if not the only TPH data available for a site, one can be faced with having to evaluate health risk for such reported mixtures. Although a variety of approaches can be used to assign toxicity factors to whole product carbon ranges, appropriate regulatory guidance on the topic should be consulted for recommended approaches. The most technically defensible approach is arguably to make assumptions about the proportions of TPH fractions comprising the released petroleum mixture and use recommended toxicity factors and chemical constants for the assumed fractions. While this approach may be the most technically defensible, it nonetheless entails more uncertainty than is associated with health risk estimates based on measured TPH fraction data. Use of this approach allows at least a screening level evaluation of whole product data. Two agencies have published guidelines for this method of evaluating health risks for whole product TPH (e.g., GRO, DRO, RRO) CASWB-SFBR 2016a; HIDOH 2017.
The whole product method of evaluating the toxicity of TPH entails more uncertainty than is associated with health risk estimates based on measured TPH fraction data. It can have value as part of a screening level evaluation, but should be used with great caution, if at all, for human health risk assessments. Local guidance should be consulted before using a whole product method for evaluating the toxicity of TPH.
This section discusses the challenges to evaluating the toxicity of the polar metabolites and the approaches that have been proposed for addressing the challenges.
6.10.1 Challenges in Evaluating the Toxicity of Polar Metabolites
It is well established that hydrocarbons (and other chemicals) undergo "weathering" (see Alterations of Petroleum Mixtures in the Environment through Weathering Processes) in the environment. Understanding the toxicity of the resulting hydrocarbon degradation of products is important because the majority, if not all, of the hydrocarbons at a petroleum release site can be present in soil or groundwater in the form of polar metabolites. Although much, if not all, of the mass of the metabolites can degrade to carbon dioxide and water eventually, the polar residues can be the source of ongoing potential or actual exposure for varying periods of time after a release. Accordingly, explicit evaluation of the metabolites may be warranted when they are present.
The same fundamental challenges of a variable and changing mixture of chemicals with sparse toxicity data on the mixtures and/or components of the mixtures that apply to the hydrocarbons at petroleum release sites also apply to the polar metabolites. In fact, the degree of uncertainty associated with understanding the chemical composition of the polar metabolites and with understanding the toxicity of polar metabolite mixtures is even greater than for the parent hydrocarbon product mixtures. The technical and practical challenges associated with a definitive characterization of the polar metabolites are such that one will never have definitive characterization of the chemical composition of the mixture at any given site.
Estimating health risks for the metabolites at petroleum release sites will require assumptions about the chemical composition and the toxicity of the mixture present and will entail at least as much uncertainty as is associated with estimating health risks at sites with releases of other chemical mixtures. The chemistry of petroleum degradation products is an active area of research and our understanding of it is likely to grow and change in the future.
As discussed in Section 4.4 the production of polar metabolites is largely the result of biodegradation, including both aerobic and anaerobic degradation processes. Chemical degradation processes (e.g., photooxidation) can also contribute to the natural attenuation process. Because polar compounds can be present in crude oil Meckenstock et al. 2014, they may be present as part of the released material at crude oil or residual oil release sites, as well as being the result of natural attenuation of hydrocarbons in these petroleum mixtures Thorn and Aiken 1998. It is important to recognize that polar compounds can also be present at a site in soil or groundwater as part of the natural background chemicals (e.g., humic acids) or from releases of other anthropogenic chemicals not related to the petroleum release. These are issues that can generally be addressed with a good conceptual site model, and the need to differentiate polar natural background substances from polar compounds may require devoting more resources to developing a more completed conceptual site model than would otherwise be the case.
It may be necessary to characterize natural or anthropogenic background sources of polar compounds at some sites prior to performing a human health risk assessment for petroleum releases. In some cases, such an evaluation is needed to allow an evaluation of the "release" separate from the evaluation of the background. Estimating the health risks associated with such background substances would require information on the concentration and toxicity of the background substances.
The polar metabolites that have been detected in at least some petroleum release site groundwater plumes consist almost entirely of oxygen-containing compounds derived from hydrocarbons CASWB-SFBR 2016b; Zemo, O'Reilly, et al. 2013; Zemo et al. 2017 that include alcohols, phenols, aldehydes, ketones, and acids/esters of dicarboxylic acids. At larger release sites, these plumes have been demonstrated to persist for decades and likely will persist much longer. The progression of metabolites through various classes of oxygenated species is well documented, but the mixture of constituents present at any given petroleum release site will be variable and will change with time Zemo et al. 2013; Zemo et al. 2017.
6.10.2 Approaches Proposed for Evaluating the Toxicity of Polar Metabolites
Two specific approaches for evaluating the toxicity of polar metabolites have been proposed. One assumes that the bulk polar metabolites have the same toxicity as the bulk hydrocarbons in the TPH fraction in which they are detected CASWB-SFBR 2016b. A second approach assigns toxicity factors for individual polar oxygenate degradation products to chemical structural families of degradation products Zemo, O'Reilly, et al. 2013; Zemo et al. 2017. Consideration of these approaches is discussed in the TPH case studies published by HIDOH 2018.
Both of these approaches are primarily intended to address refined middle distillate products in water. The focus on the middle distillate range is primarily because gasoline range organics are generally addressed by the evaluation of relatively water-soluble indicator chemicals (i.e., BTEX) and because polar metabolites of gasoline range hydrocarbons tend to have retention times in the middle distillate range. In addition, hydrocarbons larger than those in the middle distillate range from refined products have such low water solubility that they are not found dissolved in water at significant levels. One concern associated with both of these approaches is that the methods for measuring TPH-d will not always detect all of the polar compounds present in a sample and that the level of polar compound can be underestimated Bekins et al. 2016; Mackay et al. 2018.
However, residual fuels and crude oil may contain larger and different hydrocarbons (as well as other organic chemicals) than are present in refined products (e.g., PAHs, oxy-PAHs, sulfur compounds). These constituents may be metabolized by microorganisms in the environment to compounds that would be different than compounds present in releases of refined product Tissot and Welte 1984; Zemo and Foote 2003. Residual fuels and crude oils may also contain polar compounds that could be present in the parent spill material and that could be further metabolized. Thus, the range of chemical structures and the range of molecular sizes of metabolites and degradation products in weathered residual fuels and crude oils will be different from the mixtures seen in weathered releases of refined products.
As noted above, one approach to evaluating the toxicity of polar metabolites assumes that the polar metabolites have the same toxicity as the hydrocarbons detected in routine extractable TPH analyses without a silica gel cleanup (SGC) step (e.g., TPH diesel and TPH motor oil or carbon range fractions). Under the similar toxicity approach TPH concentrations could be compared to screening levels developed for hydrocarbons or could be used in a risk assessment CASWB-SFBR 2016a, 2016b; HIDOH 2017. One practical advantage of this approach is that it does not require application of a sample cleanup step to remove polar compounds. (See Case Studies, Section 11 for additional discussion of metabolite toxicity and examples of implementation).
A second approach to evaluating the toxicity of the polar metabolites involves assigning toxicity factors to various fractions of TPH that are detected after silica gel cleanup and are assumed to consist of polar metabolites of hydrocarbons. Two organizations Zemo et al. 2017; CRC CARE 2017 have developed recommended toxicity factors to be applied to the polar metabolites. Although the fundamental approach used in both cases is the same, the specific assumptions used differ, resulting in the development of different toxicity factors for the polar metabolites. In both cases, assumptions were made about the composition of the metabolite mixtures in various stages of weathering of the released product and toxicity factors were assigned to the assumed compositions. The toxicity factors developed by CRC CARE 2017 were lower than those developed by Zemo et al. 2017; and the toxicity factors developed by both groups were lower that the toxicity factors that would be assigned if the polar fractions were assumed to consist of hydrocarbons. CRC CARE 2017 noted that while the toxicity assigned to the polar compounds is less that than that of the corresponding hydrocarbons, it is not so low that it can be disregarded.
Noteworthy assumptions associated with the evaluation of the toxicity mixtures of polar metabolites include the fact that the mixture will vary as a result of the source of the hydrocarbons, as well as the conditions and duration of weathering. Consequently, there would be uncertainty surrounding the chemical composition of the mixture in addition to the validity of the toxicity assigned to any fraction of metabolites. These uncertainties apply whether the toxicity factors specific to polar metabolites are used or whether the polar fractions are assumed to have the same toxicity as the corresponding hydrocarbons.
6.11 Toxicity Considerations for Different Exposure Routes
Any uptake of hydrocarbons into plant or animal material will also involve a substantial fractionation of the hydrocarbon mixture with only a subset of the hydrocarbons being absorbed into the plant or animal and distributed to the edible portions. As noted above, TPH extraction methods will extract chemicals other than hydrocarbon from plant and animal material. Accordingly, TPH analyses cannot be used for the evaluation of hydrocarbon exposure from consumption of plant and animal material. An indicator chemical approach is required instead.
Consideration of the site-specific hydrocarbon mixture to which plants and animals are exposed and the mechanism by which they may take up the hydrocarbons will be important in the selection of appropriate indicator chemicals. For plant and animal exposures involving migration or solution into water as a first step, one would need to consider the fact that hydrocarbons soluble in water would be expected to be limited primarily to aromatic compounds with carbon sizes of approximately C14 and lower, and that larger aromatic structures and almost all but the smallest aliphatic structures have limited solubilities in water.
As with hydrocarbons, different portions of the degradation product mixture can be expected to partition to different environmental media, based on their chemical and physical properties. When evaluating exposure via inhalation (e.g., from vapor intrusion), the chemical constituents expected are generally limited to the most volatile constituents of a released petroleum mixture. The mixture may include degradation products (e.g., methane), but is not likely to include polar metabolites. Selecting a hydrocarbon representative of the volatile hydrocarbons expected in indoor air and soil gas could address the toxicity of the parent hydrocarbons, as well as any degradation products for the inhalation exposure pathway.
When considering potential exposure from water, gasoline range compounds are thought to be essentially limited to soluble hydrocarbons and not to include polar metabolites, which are expected to have retention times that would be detected in the middle distillate range of a TPH analysis. TPH measured in water originating from releases of middle distillate products (e.g., diesel fuel, Stoddard solvent, heating oil, jet fuel, etc.) into water can be present in water largely, if not entirely, in the form of polar degradation products. This is a function of the polar chemical structures, which are inherently more soluble in water than hydrocarbons. Hydrocarbons soluble in water from these products would be expected to be limited primarily to aromatic compounds with carbon sizes of approximately C14 and lower. Larger aromatic structures and almost all but the smallest aliphatic structures have limited solubilities in water.
Although it has been shown that polar degradation products can form in soil Mao et al. 2009a, general assumptions about the mix of metabolites and the fraction of material detected as TPH that is parent hydrocarbon versus metabolites are particularly elusive. Several factors that can affect the composition of polar degradation products following a petroleum release were identified (e.g., specific hydrocarbon product(s) released, chemical and microbial conditions in soil, time since release(s), etc.). It was also noted that a significant fraction of the material detected as TPH in soil samples analyzed by routine TPH analytical methods can be natural organic components of soil, particularly for organic-rich soil types, such as peat. The presence of such natural, organic soil components complicates any attempt to separately characterize the petroleum metabolites and parent petroleum compounds from the mixture of substances making up the TPH measured in soil samples.
It is plausible that TPH degradation products could be taken up in the food pathway as a result of irrigating food crops with water containing petroleum or as a result of uptake into fish from surface water releases, for example. It is not clear, however, which mixtures of degradation products or which individual degradation products would be taken up into a food exposure pathway, and thus, it is not clear what toxicity factors would be representative of any polar degradation products taken up into plants or animals in the food chain. Because many of the naturally occurring organic compounds making up plant and animal materials would report as TPH when measured using routine (bulk) TPH analyses, these analyses would not provide a valid measurement of the level of petroleum hydrocarbons or polar degradation products in plant or animal food products. Food pathways are typically evaluated using indicator chemical approaches. At some time in the future, it may be possible to select site-specific indicator chemicals for polar degradation products, but this is not currently possible using the best available scientific methods.
Risk characterization is the final step of the human health risk assessment process, and it has been described as the bridge between risk assessment and risk management because it provides a basis for risk estimation and an understanding of the results and uncertainties that are inherent in each step of the evaluation. ITRC 2015 described key issues associated with risk characterization and organized these into topic areas of risk results, presentation of risk results; and uncertainty and bias. More information on risk characterization is also available on USEPA's Human Health Risk Assessment web page (USEPA 2017c Step 4, Risk Characterization).
Major assumptions, scientific judgments, and to the extent possible, estimates of the uncertainties embodied in the risk assessment are presented in the risk characterization. For risk assessments involving TPH, the understanding and description of uncertainty and bias can be even more challenging because TPH is often viewed as a "complex mixture" that is unique from other complex mixtures (e.g., Aroclors). The approach to characterizing the risks from TPH may not be entirely unique, although many assumptions associated with the measurement, fate and transport, toxicity, and risk estimation for TPH are unique and will vary depending on the specific approach being taken to TPH in any given risk assessment. Identification and discussion of how the TPH-specific uncertainties can influence results and conclusions is an important component of any TPH risk assessments.
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Fisker 2012 Karma being an absolute perfect sedan for almost every class can make you breathless.
Talking about its features, it has four doors plug-in that are hybrid, which give up to 50 miles on electric power. Karma has seats for four, it gives up to 250 miles on gas power, it has optional "animal-free" interior and offers Zero to 60 mph as quick as 6.3 seconds. Its engine is quite strong with 403 hp (electric) and 1 speed automatic transmission. It is a heavy vehicle, and its most appreciated features are: Styling, Quick in Sport mode, balanced weight, Charges at 120 or 240 volts, Zero tailpipe emissions for 50 miles and Cool pedestrian-alert sound.
Fisker 2012 has 959 lbs.-ft torque, and the fuel capacity is 9.0 gal. It has 4 doors Solar panel sunroof, Cruise control that has steering wheel controls, Power fuel remote release, integrated key/remote, doors that are auto-lock, Steering wheel with power tilting, power telescoping, mirror with the feature of Day-night rearview, Front and rear cup holders and rearview mirror with auto-dimming feature.


Dr. Vishnu Vageesa Sharma completed his MBBS from Kerala University in 1995. Dr. Vishnu obtained his MD from Delhi University.
He has trained in several courses affiliated by international cardiology societies. He has European and Indo-American accreditations in Echocardiography.
Dr. Vishnu has a vast experience in the fields of Cardiology and Internal medicine. He was previously associated with Escorts Heart Institute, New Delhi as a Cardiologist.
His special areas of interest include cardiac risk assessment, ECG and holter analysis, non-invasive cardiac imaging including Echocardiography and Stress Echocardiographic interpretation.
Dr. Vishnu can speak in English, Hindi, Tamil and Malayalam.


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text:
ILWU Delegates Recommend Tentative Agreement
06 Apr ILWU Delegates Recommend Tentative Agreement
ILWU Coast Longshore Caucus delegates voted Friday to recommend approval of the tentative agreement reached on Feb. 20, 2015, between the union and employers represented by the Pacific Maritime Association (PMA).
The tentative agreement was approved on Feb. 20 by the ILWU's 16-member elected Negotiating Committee and 8-member Safety Sub-Committee. The proposed 5-year contract covers 20,000 dockworkers at 29 west coast ports.
As reported, the tentative agreement was reached after more than nine months of negotiations. Both sides agreed at the time that operations at all 29 ports would return to normal by Feb. 21 pending ratification, although clearing the backlog of containers clogging port yards was expected to take some time. The PMA had halted vessel loading and unloading twice in February to avoid paying overtime to ILWU worker it said were intentionally slowing port operations to gain leverage in the negotiations, leading to widespread disruptions of receipts this year.
All 90 delegates to the Coast Longshore Caucus spent this week reviewing the proposed agreement lineby-line, before voting by 7 percent to recommend the proposal on Friday.
"This agreement required ten months of negotiations – the longest in recent history," said ILWU International President Bob McEllrath, "but we secured a tentative agreement to maintain good jobs for dockworkers, families and communities from San Diego to Bellingham. Longshore men and women on the docks will now have the final and most important say in the process."
Copies of the agreement will be mailed to longshore union members, who will then have a chance to discuss the proposal at local union meetings. A secret ballot membership ratification vote will be the final step in the process. A final tally will be conducted on May 22.

redpajama_set_name: RedPajamaCommonCrawl


Hillary Supporter Attacks Jewish Man at Starbucks.. Then Loses Her Job!
Thread: Hillary Supporter Attacks Jewish Man at Starbucks.. Then Loses Her Job!
So anyway, this nutcase leftie goes bananas at a guy who wore a Make America Great Again Hat.
She takes photos and call him a Nazi.
He's Jewish ! OMG, so funny.
Yes the Right and Left side of modern culture are both stupid and evil.
omg, a unity ticket ! who would have thought.


text:
Second-half spark from substitutes helps Philadelphia Union rescue point in New England
Fafa Picault provided a second-half spark off the bench for the Philadelphia Union and set up their late equalizer against New England on Wednesday.
Joe Tansey, Pro Soccer USA
FOXBOROUGH, Mass. — At halftime of their match with the New England Revolution, the Philadelphia Union knew they had to pack more of a punch on the field.
It took the Union longer than they hoped to equalize the contest at Gillette Stadium, but they came away with a 1-1 result thanks to the impact made by substitute Fafa Picault on Kacper Przybylko's 84th-minute strike.
"Honestly, New England was playing very tough," Przybylko said. "They played very good defense. At halftime, we had to prepare for the fight. They were fighting and we were not so we did it better in the second half and we also changed the system and everyone did well in the second half."
At the start of the second half, the Union opened up the Revolution defense by switching to a 4-2-3-1 with Ilsinho inserting into the game on the right wing.
The formation change allowed Sergio Santos to make some dangerous runs on the left wing and tire out some of the New England defenders.
"With the turf, it's tough to pass and connect balls," Union head coach Jim Curtin said. "Credit to them, they were organized defensively and broke up a lot of the passing lanes. We decided to be a little more direct, play balls in and fight for second balls. Sergio did a good job of stretching them, I thought we did a good job in behind and made their back four turn and face their own goal for the first time in the second half."
In the 62nd minute, Curtin brought on Picault to throw another fresh set of legs at the Revolution, and eventually the hard work of the 28-year-old paid off.
"I'm used to the 90 minutes after last year," Picault said. "I hate the bench, honestly, but my job is to come on and when I do have my minutes show what I'm capable of doing. All the defenders around the league now it and it's not a secret. Just keep giving them problems and I think that's happens when I do that."
Picault blasted through a slew of defenders on the right side of the penalty area and picked out Przybylko, who made the final touch after a deflection off Andrew Farrell to get credit for his fifth goal of the season.
Slow feet don't eat! Speedy run from @Fafagoal23 and Kacper finishes off the run!#NEvPHI 1-1 | #DOOP pic.twitter.com/HFdyM5dPet
— Philadelphia Union (@PhilaUnion) June 27, 2019
"It's my job being in the box," Przybylko said. "I saw Fafa was moving outside and I know he had two options. He shoots, or he plays the ball inside and he played the ball inside and I was staying there like a typical striker just waiting for the ball."
The late equalizer made up for a slew of mistakes that were littered throughout the first half, and were most evident on Brandon Bye's 31st-minute opener in which the Union's set-piece defending fell apart.
Bye Bye Bye to this scoreless match!#NERevs // #NEvPHI pic.twitter.com/8FnZ669X3V
— New England Revolution (@NERevolution) June 26, 2019
"It's disappointing that we conceded in the first half off a restart," Curtin said. "We talked a lot about doing our jobs, Sergio made a mistake. He at least put his hand up and knew he made a mistake. I'm proud of the guys for picking him up, but it's a little bit inexcusable on the corner kick to concede."
The Union were able to hold the Revs to one goal because of their defending in the box, three saves from Matt Freese and a handful of missed opportunities from the Revs attackers.
"I was definitely very happy to make some saves, but by no means, were they any incredible saves," Freese said. "They were pretty routine saves. Kacper came up big with a goal line save. Jack had a few really good clearances. Ray had a bunch of things on his side. In general, I think it was a really good team effort to keep it 1-0 and then after that, getting the equalizer is huge."
"I don't honestly remember them having a big chance to score," Przybylko said. "They just scored the one goal when everybody slacked off on our team. Every point counts and every point is important."
Jun 26, 2019; Foxborough, MA, USA; Philadelphia Union midfielder Brenden Aaronson (22) reacts after being issued a yellow card during the first half against the New England Revolution at Gillette Stadium. Mandatory Credit: Greg M. Cooper-USA TODAY Sports
Now the Union face their toughest test of their three-game road swing on Saturday versus New York City FC at Yankee Stadium.
The Union are nine points ahead of NYCFC, and thanks to Wednesday's draw, they have a point that may prove to be valuable come October.
"In the middle summer months, picking up any points on the road is critical," Curtin said. "It's a time now where both teams and a lot of the league is on a long layoff. There's going to be rust. It's good to get that one out of our system now and we have a really tough NYCFC opponent in their building and it's two teams that are at the top of the conference. Only one team has beaten NYCFC. People tend to forget that this year. They're a really good team and we'll have a tough test there."
Related TopicsFafa PicaultfeaturedJim CurtinKacper PrzybylkoNew England RevolutionPhiladelphia Union
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Jamiro Monteiro has joined the Philadelphia Union on a permanent basis from FC Metz.
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NYCFC rallies for three unanswered goals in thrilling win over Philadelphia Union


text:
Q: Angularjs $http does not call the api in GET request I have been trying to call an API using $http.get method but its not calling that API instead just returning 404 error.
My $http

$http({
  method: 'POST',
  url: '/SalesManagement/SecuredSalesAPI/GetProductLine'
}).then(function(res) {
  debugger
  console.log(res.data);
}, function(header) {
  debugger
  console.log("HTTP Head: " + JSON.stringify(header));
});
//My route public class SalesManagementAreaRegistration : AreaRegistration { public override string AreaName { get { return "SalesManagement"; } } public override void RegisterArea(AreaRegistrationContext context) { context.MapRoute( "SalesManagement_default",
"SalesManagement/{controller}/{action}/{id}", new { action = "Home", id = UrlParameter.Optional } ); } }

My API:
public class SecuredSalesAPI : Controller
{
    public JsonResult GetProductLine()
    {
        var sp = entity.spGetProductPerformance(startDate, end, "HPL");
        return Json(sp, JsonRequestBehavior.AllowGet);
    }
}

// and the namespace is
// namespace WebApp.Areas.SalesManagement.Controllers

A: You trying to get but you defined method as post.

$http({
  method: 'GET',
  url: '/SalesManagement/SecuredSalesAPI/GetProductLine'
}).then(function (res) {
  debugger
  console.log(res.data);
}, function (header) {
  debugger
  console.log("HTTP Head: " + JSON.stringify(header));
});

A: Change the method to 'GET' instead of 'POST'
$http({
            method: 'GET',
            url: '/SalesManagement/SecuredSalesAPI/GetProductLine'
        }).then(function (res) {

            console.log(res.data);
        }, function (header) {

            console.log("HTTP Head: " + JSON.stringify(header));
        });

Also add keyword controller to your controller class name. ie;
public class SecuredSalesAPIController : Controller
{
}
and call the service from client side as before.

A: API only pass data by url.you have to use GET method to get data.
$http({
    method: 'GET',
    url: '/SalesManagement/SecuredSalesAPI/GetProductLine'
}).then(function(res) {

    debugger
    console.log(res.data);

}, function(header) {

    debugger
    console.log("HTTP Head: " + JSON.stringify(header));

});

redpajama_set_name: RedPajamaStackExchange


Many folks hope to find a home where they feel comfortable, and a church where they experience belonging. We are pleased you have decided to visit Bethesda, and hope you will discover this is a home where you feel comfortable and experience belonging, and can put down roots to through fellowship and service with others.
Please look around our website to see more about who we are. Welcome!


After finding her own practice, Anneke Sips, a yoga teacher and social psychiatric nurse (RN) from Amsterdam, the Netherlands, began to dream of bridging her two passions, yoga and psychiatry. In the latest interview for our yoga service series on The Huffington Post, Executive Director Rob Schware talks with Anneke about her work to make this dream come true, and her experiences with teaching yoga to special populations, specifically to those with chronic psychiatric illnesses.
To read more about Anneke's work with special populations and her thoughts on the future of yoga service, read her full interview on The Huffington Post Blog.
Awaken…transform…give back. Inspire your service and learn how to make yoga accessible to those who might not otherwise experience this transformational practice by connecting with Give Back Yoga Foundation by email.


Imagine This is comprised of highly qualified and experienced professionals with the passion and discipline to deliver best-in-class service to each and every casino partner we work with. Our Client Services team offers decades of experience working either at a casino property or within the casino promotional marketing field. We know your challenges. We understand your world. We possess the ability and the know-how to help you generate serious incremental revenue and net profit for your property – while making your life easier in the process!


It seems that everyone is talking about email this week. On the I, Cringely blog, Bob Cringely writes about "The Decline and Fall of E-Mail." Many of his commenters point out that for folks who work in "regular" jobs, email is definitely not in decline. Eric Stoller agrees with those commenters in his love letter to email over at Inside Higher Ed.
If you're a blogger, check out the #reverb10 challenge, an annual event designed to "reflect on your year and manifest what's next." You sign up to receive daily prompts in your email and pledge to blog about the prompts throughout the month of December. I posted my first entry today over on my personal blog and am looking forward to the challenge of blogging daily. If you do sign up, please leave a link to your blog in the comments so we can follow your entries.
Speaking of bloggers, Kikolani published a list of 125 Fearless Female Bloggers. Go check it out and add some new favorites to your Google Reader.
The Boston Globe had a great piece this week on Information Overload, 15th-Century Style, while HASTAC published a good response to the New York Times' latest entry in the "kids today" genre. (Truly, I am so over those articles. I've been teaching for 15 years now and every year, my colleagues and I complain about our students' lack of attention. And I'm pretty sure my teachers complained about my lack of attention. Can we please stop blaming Facebook?).
Over the break, I spent a lot of time playing around with new tools. One that holds great promise for anyone who produces written content (so bloggers, teachers, writers, etc.) is Scrivener. Long a cult favorite among Mac users, there's now a Windows beta version as well. I also stumbled across a great post on using Scrivener to organize classes — even if you don't teach, the tips are useful for organizing other kinds of content. While I haven't had much time to play with it yet, it looks very promising.
I'm doing #Reverb10! So excited to participate – lots of good blog posts, coming your way. And maybe some day I'll get back to posting on here!


The slit system achieves more precisely positioning. This is designed for a higher request of precisely X-ray shaping for a small sample measurement or nano- or micro-beam focusing.
Motion is transmitted to each blade with linking rod which passes through the chamber and supports the blade.The slit blade has curved shape (radius 5mm). It is used for small angle X-ray scattering experiment.
This small and thin compact slit can be used under Low vacuum environment. Motion is transmitted to each blade with linking rod which passes through the chamber and supports the blade with Oring seal.


"Pre-heat oven to 325 degrees."
"In a large bowl, toss together oats, hazelnuts, coconut, flax seed, cinnamon and salt."
"Drizzle oat mixture with melted coconut oil and honey then use a rubber spatula to make sure all ingredients are evenly coated."
"Line a baking sheet with oven-safe parchment paper or a silicone baking mat and spread granola mixture out in an even layer."
"Bake until golden brown, about 30 minutes, stirring once halfway through."
"Let granola cool on cooling rack for 30 minutes before pouring into a large bowl. Toss dried blueberries into the granola before serving."


text:
Q: Search for a struct item in a vector by member data I'm very new to c++ and I'm trying to find a way to search a vector of structs for a struct with a certain member data.
I know this would work with simple types in the vector
std::find(vector.begin(), vector.end(), item) != vector.end()

But lets say I have a struct like this:
struct Friend
{
  string name;
  string number;
  string ID;
};

and a vector like this:
vector<Friend> friends;

Then the vector is filled with friends.
Let's say I want to search for a friend with a certain ID, and cout the details. Or delete the certain struct from the vector. Is there a simple way to do this?

A: You can use std::find_if in combination with functors (if you are working with C++98) or lambdas (if you are using C++11, which I will assume):
using namespace std;
int ID = 3; // Let's say...
auto it = find_if(begin(vector), end(vector), [=] (Friend const& f) {
    return (f.ID == ID);
    });
bool found = (it != end(vector));

A: If you want to find an element in STL container, use std::find or std::find_if algorithms
With C++03, you need to overload operator== for std::find
bool operator==(const Friend& lhs, const Friend& rhs)
{
  return lhs.ID == rhs.ID;
}

if (std::find(friends.begin(), friends.end(), item) != friends.end())
{
   // find your friend
}

OR C++11 with lambda:
std::find_if(friends.begin(), friends.end(),  [](Friend& f){ return f.ID == "1"; } );

If you want to remove a certain element, use std::remove_if
std::remove_if(friends.begin(), friends.end(),
      [](Friend& f){ return f.ID == "1"; });

A: This can be done with std::find_if and a search predicate, which can be expressed as a lambda function if you have C++11 (or C++0x) available:
auto pred = [](const Friend & item) {
    return item.ID == 42;
};
std::find_if(std::begin(friends), std::end(friends), pred) != std::end(friends);

To use an ID given as a variable, you have to capture it in the lambda expression (within the [...]):
auto pred = [id](const Friend & item) {
    return item.ID == id;
};
std::find_if(std::begin(friends), std::end(friends), pred) != std::end(friends);

If you don't have C++11 available, you have to define the predicate as a functor (function object). Remy Lebeau's answer uses this approach.
To remove elements matching the criteria as defined by the predicate, use remove_if instead of find_if (the rest of the syntax is the same).
For more algorithms, see the STL <algorithm> reference.

A: Use std::find_if().  @leemes and @AndyProwl showed you how to use it in a C++11 compiler.  But if you are not using a C++11 compiler, then you can use it like this instead, which defines a functor comparing the ID of a given item with a previously specified ID in its constructor:
class MatchesID
{
    std::string _ID;

public:
    MatchesID(const std::string &ID) : _ID(ID) {}

    bool operator()(const Friend &item) const
    {
        return item.ID == _ID;
    }
};

std::find_if(vector.begin(), vector.end(), MatchesID("TheIDHere")) != vector.end();

If you have other classes in your project which use IDs, you can make this functor templated:
template<typename IDType>
class MatchesID
{
    IDType _ID;

public:
    MatchesID(const IDType &ID) : _ID(ID) {}

    template<class ItemType>
    bool operator()(const ItemType &item) const
    {
        return item.ID == _ID;
    }
};

std::find_if(vector.begin(), vector.end(), MatchesID<std::string>("TheIDHere")) != vector.end();


This is the boom of the startups in the world. Everybody wants to join in what seems to be a way to solve the world's problems, or maybe simply seeing the boom as a gold mine to jump in. Either way, we live in a world where the customer is king. This means we need to drive engagement and increase traffic to us! What better way to do that than to have slick icon designs at your disposal. Actually, what's better than that is to have 90 icons to elevate your startup to a whole new level!
All of these 90 Business Startup Icons are made for you, whether you want to start your own startup, or you work for a startup, or even if you're simply looking for ideas and inspiration! These icons can be used however you want it. App design? Website? Mobile web? Offline? You can do it!


I've an android list activity that's backed with a database cursor via a SimpleCursorAdapter.
Once the products are clicked on, a flag area within the coresponding row within the database is toggled and also the view within the list must be up-to-date.
The issue is, once the view that's up-to-date chimes screen and it is recycled, that old value is shown on the vista if this returns into view. Exactly the same factor happens whenever thr list is redrawb (orientation changes, etc).
I personally use notifydatasetchanged() to refresh the cursor adapter however it appears ineffective.
How must i be upgrading the database therefore the cursor is up-to-date too?
Call requery() around the Cursor whenever you change data within the database that you would like reflected for the reason that Cursor (or things the Cursor populates, just like a ListView using a CursorAdapter).
A Cursor is similar to an ODBC client-side cursor -- it holds all the data symbolized through the query result. Hence, simply because you alter the information within the database, the Cursor won't learn about individuals changes unless of course you refresh it via requery().
This process is deprecated. Avoid using this. Just request a brand new cursor, so this can be done asynchronously increase your list view when the new cursor returns.
after acquiring a brand new cursor it's possible to make use of theadapter.changeCursor(cursor). this will update the vista.
What is with this particular rollover?
Apache: Steps to make exactly the same rewrite rule without needing THE_REQUEST?
Which of those 2 database configurations must i choose?
Can One use Bind Variables with odp.internet and Oracle 8i?


text:
Talkhouse Weekend Playlist: A Recipe for a Daydream
The Brazilian artist Winter shares a dreamy playlist ahead of her debut record.
It feels like 2020 needs a big dose of escapism. We need art to distract us from the news, to entertain us while we wait inside, and to help us heal. Rising dream-pop artist Winter has brought the right ingredients to the table. Her debut album, Endless Space, is a melting pot of dream pop, psychedelia, and shoegaze. The record is due later this summer on Bar/None records. However, for today, Winter has this recipe for a daydream. Bon Appétit.
—Keenan Kush, Talkhouse Operations Manager
I love a solid daydream sesh! So much of my inspiration for Winter comes from lying down and listening to dreamy music in my bedroom. I would highly recommend a disco ball or some sort of colorful lighting if it's indoors, or a nice patch of grass or sand if it's outdoors. Tinted sunglasses take it to the next level. What makes a song good for daydreaming? Hmmm it needs to make you feel like a teenager in love or the feel the love low of the morning after an all nighter hanging with your friends. It needs to make you feel like you're in a '90s movie driving through saturated colored lights in slow-motion. It's pure catharsis; when you ask yourself the most existential questions like "What is life? What is love? How is this flower so perfect?…" If it were a recipe I would put in a cup of nostalgia, another half cup of beautiful sounds, a tablespoon of innocence and a teaspoon of sadness. Here are the songs that melt my heart away into daydream land.
—Samira Winter
Hatchie — "Sure"
I still cry every time I listen to this song. It's the perfect combination of dream + pop. It takes me back to dancing on my bed in middle school days pretending I was in a music video and singing along to pop songs like "Why Can't I Breathe" by Liz Phair and "Dreams" by The Cranberries.
ivy — "Decay"
This song is my favorite kind of sad. Like I'm having to say goodbye to my best friend because I'm moving away, or when you know things are changing for the better but it's still hard to say goodbye.
The Sundays — "Here's Where the Story Ends"
Just turn this up really loud and dance!
Erasmo Carlos — "Vida Antiga"
This one is best with yellow tinted shades. The song literally talks about the "old life" you used to live. That plus some soft singing in Portuguese makes me nostalgic of a time and life I've never lived.
Yo La Tengo — "Shadows"
A very important characteristic of daydreaming is that you usually do it alone. Nothing like some good ol' Yo La Tengo to get deep in there and connect with your deepest darkest self. I suggest turning off all the lights for this one.
Gold Celeste — "Time of Your Life"
Definitely one of my favorite songs ever and a huge influence on my upcoming record (like there's songs I wouldn't have written if I hadn't heard this song). You can just feel a sunset on the horizon and the tingle that anything could happen… aaah.
Alvvays — "Party Police"
Fuck, this song. I can't even handle it.
Ringo Deathstarr — "Kaleidoscope"
This song is a shoegaze romance anthem. Star projector, sparkle blue jazzmaster and an all black outfit are a must. "Can you show me colors that no one knows…" Come onnnn! Breaks my heart in the best possible way.
Shower Curtain — "All That You Do"
No one best to write a dreamy love song than your baby sister. This song immediately puts me into daydream mode. I just close my eyes and remember the feeling of falling in love when I was 19.
Beach House — "Saltwater"
Love you all the time, even though you're not mine.
(Photo Credit, left: Angel Aura)
How a Video Store Became My Film School in '90s Brazil
The Way We Get By: Faith Vern (PINS) Finds Iggy Pop's Free To Be a Nice Escape.
An Illustrated Guide to The Twin
Talkhouse Weekend Playlist: Take a Long Summer Drive with Hatchie
Talkhouse Weekend Playlist: Gold Celeste's Top Tracks of the 2010s
Sean Lennon (The Ghost of a Saber Tooth Tiger) Talks with Les Claypool (Primus) for the Talkhouse Music Podcast
Meredith Graves (Perfect Pussy) Talks Beach House's Depression Cherry


Math isn't just a subject in school—it's a fundamental, creative tool that artists and engineers use to design and invent! Visitors can solve real-world engineering challenges with Design Zone, an exhibit that contains three interactive thematic areas, highlighting the relationship between mathematical thinking and the creative process in art, music, and engineering. Each thematic area draws visitors into real-life scenes of music production, video game development, and extreme sports that directly and experientially relate mathematical concepts. Design Zone's range of interactive experiences cater to a wide variety of visitors, with special emphasis on families and school groups, and visitors ages 10-14.
Balancing Art—Visitors discover the math behind mobiles by creating their own balancing art from colorful pieces.
Build a Tower—Visitors challenge their ability to continue a pattern in three dimensions by building a tower from custom printed architectural blocks.
Marble Maze—Navigate mazes, avoid the black holes, and roll over stars to collect points. Visitors adjust variables and design a game that results in a high score.
Drum Machine—Visitors pick sounds and number of repeats for a two-beat track, a three-beat track, and a four-beat track, and are challenged to get all three tracks to end on the same beat.
Whack-a-Phone—By whacking tubes of different lengths, visitors can make music! The length of the tube determines the pitch.
Light Show DJ—Visitors step into the control booth at a virtual concert and put together laser light patterns to match the music to get the crowd dancing.
Roller Coaster Hills—The first step in roller coaster design is to understand the relationship between hill height and distance traveled. Visitors experiment with ramps of different heights to design their own roller coaster.
Fast Tracks—This giant magnet wall lets visitors create and test roller coaster course designs.
A printable fact sheet about Design Zone (mid-size).
Tour Schedule for Design Zone (mid-size).