Evaluation of potential transmission of 2,3,7,8-tetrachlorodibenzo-p-dioxin-contaminated incinerator emissions to humans via foods
- Department of Agriculture, Beltsville, MD (USA)
Interest in the potential sources of human exposure to TCDD (dioxins, TCDD and equivalents, or 2,3,7,8-tetrachlorodibenzo-p-dioxin) via foods has recently shifted from phenoxy herbicides to products of combustion and waste disposal. Proposals to locate municipal waste combustors in rural areas have raised concerns that emissions, which could contain TCDD, could contaminate animal feeds and such human foods as milk, meat, and vegetables. Important factors that can affect the results of an assessment of incinerator emissions include (1) the emission and deposition rates of TCDD from the source, (2) the fractional retention and half-life of fly ash on plants, (3) the environmental half-life of TCDD, (4) the animal feeding and management systems, (5) the bioavailability of TCDD and related compounds, (6) the metabolism and pharmacokinetics of TCDD in farm animals, (7) food consumption levels, (8) the half-life of TCDD in humans, and (9) the model selected to estimate cancer risk. For persons living in the area of highest deposition near an incinerator, a possible uptake of TCDD from foods of animal origin was estimated to be about 10-40 fg/kg.d, which was much greater than the 1-5 fg/kg.d uptake estimated for foods of plant origin. The total uptake of TCDD from foods by the maximally exposed population will usually be about 500- to 1000-fold greater than that due to inhalation. Although milk was assumed to be the most important food pathway in several previous assessments that evaluated the hazards of airborne emissions, we determined that the deposition-forage-cattle-beef pathway was the more important route of exposure. The previous assessments appear to have used inappropriate pharmacokinetic models for TCDD and to have overestimated pasture use for dairy cows. 144 references.
- OSTI ID:
- 6936591
- Journal Information:
- Journal of Toxicology and Environmental Health; (USA), Journal Name: Journal of Toxicology and Environmental Health; (USA) Vol. 29:1; ISSN JTEHD; ISSN 0098-4108
- Country of Publication:
- United States
- Language:
- English
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63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AIR POLLUTION
ANIMALS
BIOLOGICAL AVAILABILITY
BIOLOGICAL HALF-LIFE
CONTAMINATION
DIOXIN
DOCUMENT TYPES
ENVIRONMENTAL EXPOSURE
FOOD CHAINS
HETEROCYCLIC COMPOUNDS
INCINERATORS
LAND POLLUTION
MAMMALS
MAN
MANAGEMENT
METABOLISM
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
POLLUTION
PRIMATES
REVIEWS
RISK ASSESSMENT
SOILS
TOXICITY
VERTEBRATES
WASTE DISPOSAL
WASTE MANAGEMENT