Proposed occupational exposure limit for 2,3,7,8-tetrachlorodibenzo-p-dioxin

Journal Article · Thu Sep 01 04:00:00 EDT 1988 · Am. Ind. Hyg. Assoc. J.; (United States)

DOI:https://doi.org/10.1080/15298668891380088· OSTI ID:6864623

Leung, H W; Murray, F J; Paustenbach, D J

One contaminant produced unintentionally during the manufacture of chlorophenols and phenoxy herbicides is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The resulting TCDD-containing wastes have been detected at many hazardous waste sites which in recent years have been in the process of remediation. Concerns about worker exposure to TCDD-contaminated soil (dust) during remediation of hazardous waste sites have produced a need for an occupational exposure limit (OEL) for TCDD. The animal toxicology data and human experience with TCDD are reviewed, and an occupational exposure limit for TCDD is proposed. The animal data support risk estimations which are based on TCDD as a nongenotoxic carcinogen. Studies on human populations have failed to demonstrate clearly any significant long-term health effects at levels to which humans have been exposed. The data indicate that an 8-hr time-weighted average limit of 2 ng/m3 is appropriate, and the associated risk would be consistent with other carcinogens at their corresponding OELs. A preliminary OEL of 0.2 ng/m3 (200 pg/m3) is recommended, however, in light of other sources of exposure because of TCDD's ubiquitousness in the environment, its unclear mechanism of action, and its rather long biological half-life in humans. This limit provides an ample margin of safety to prevent chloracne following repeated, acute exposure, and it addresses those chronic effects of TCDD observed in animal studies as well as those observed after accidental human exposure. The resulting body burden caused by chronic exposure to TCDD at the proposed OEL is examined. Its toxicological significance is compared with human tissue data and with other similarly persistent chemicals. 74 references.

• Research Organization: Environmental Health and Safety, Syntex, Inc., Palo Alto, CA (USA)
• OSTI ID: 6864623
• Journal Information: Am. Ind. Hyg. Assoc. J.; (United States), Journal Name: Am. Ind. Hyg. Assoc. J.; (United States) Vol. 49:9; ISSN AIHAA
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOLOGICAL HALF-LIFE
BODY BURDEN
CARCINOGENS
CHRONIC EXPOSURE
DIOXIN
DOCUMENT TYPES
HAZARDOUS MATERIALS
HAZARDS
HEALTH HAZARDS
HETEROCYCLIC COMPOUNDS
MATERIALS
MAXIMUM PERMISSIBLE EXPOSURE
MUTAGENS
OCCUPATIONAL DISEASES
OCCUPATIONAL EXPOSURE
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PERSONNEL
REVIEWS
RISK ASSESSMENT
SAFETY STANDARDS
STANDARDS
TERATOGENS