With approximately 450,000 active CPAs in the United States, the CPA certification is the most popular professional designation for accountants. Earning the CPA designation is no easy feat, as the CPA exam is known for its extreme difficulty.
Toxicokinetics (often abbreviated as 'TK') is the description of both what rate a chemical will enter the body and what occurs to excrete and metabolize the compound once it is in the body. It is an application of pharmacokinetics to determine the relationship between the systemic exposure of a compound in experimental animals and its toxicity.
Toxicity is a measure of the poisoning strength of a chemical. Chemicals that are only weakly toxic require large doses to cause poisoning. Strongly toxic chemicals only need small doses to cause poisoning. Toxicologists often use animal tests to determine whether small or large doses of a particular chemical cause toxicity. One such test measures the dose of a chemical that causes death to 50% of the animals being tested. This test is called the Lethal Dose 50 (LD 50). There is a tendency to think of chemicals in terms of those which are poisonous or toxic and those which are harmless.