the exposure exposure times. When by occupation exposure was expressed as years no asbestosis was found at autopsy when exposure was <2 fibre/mL-years, even after 31-45 years of residence time. In the group exposed to >2-5 fibre/mL-years asbestosis was found (4 deaths). If a threshold dose for asbestosis does exist it is at approximately 2 fibre/mL if off-shift exposure is ignored. No threshold demonstrated. Hein et al RMA ID: Follow-up 3072 textile Carolina Cumulative Fibre Duration of Asbestos Mortality study of (2007) 067597 of Chrysotile plant workers chrysotile exposure: concentration employment: chrysotile exposure exposure Textile (59% men) asbestos N=3072; method used: N=3072; and cause of death producing Workers: textile plant Median=5.5 statistical median=1.1 as indicated within pneumoconiosis Cohort modelling of the National Death seen at 3-<16 36=asbestosis Mortality and nearly 6000 years Index fibre/mL-years deaths (1960- Small fibre/mL-year industrial 36 asbestosis deaths 2001) amounts of Response hygiene (US expected deaths = crocidolite samples taken 0.15; SMR=232.5; from South over the No smoking 95%CI: 162.8, 321.9; Africa period history p<0.01) Carolina and expected deaths analysed =0.33; SMR=108.2, using Phase 95%CI: 75.8, 149.8).
the exposure by occupation exposure times. When exposure was expressed as no asbestosis was found at autopsy when exposure was <2 fibre/mL-years, even after 31-45 years of residence time. In the group exposed to >2-5 fibre/mL-years asbestosis was found (4 deaths). If a threshold dose for asbestosis does exist it is at approximately 2 fibre/mL if off-shift exposure is ignored. No threshold demonstrated. Hein et al (2007) RMA ID: 067597 Follow-up of Chrysotile Textile Workers: Cohort Mortality and 3072 textile plant workers (59% men) 36=asbestosis deaths (1960- 2001) No smoking history Carolina chrysotile asbestos textile plant Small amounts of crocidolite from South Africa Cumulative exposure: N=3072; Median=5.5 fibre/mL-year Fibre concentration method used: statistical modelling of nearly 6000 industrial hygiene samples taken over the period and analysed using Phase Duration of employment: N=3072; median=1.1 years Mortality study of chrysotile exposure and cause of death as indicated within the National Death Index 36 asbestosis deaths (US expected deaths = 0.15; SMR=232.5; 95%CI: 162.8, 321.9; p<0.01) Carolina expected deaths =0.33; SMR=108.2, 95%CI: 75.8, 149.8). Asbestos exposure producing pneumoconiosis seen at 3-<16 fibre/mL-years years Response
asb_reasons10.12.2015.docx