Inhalation, dioxin exposure

The food chain is the primary pathway of human exposure to dioxin, with meat (38%) and dairy products (28%) dominating. Fish ingestion can be a significant contributor in countries with high fish consumption (26% of total intake in the Netherlands), but is not an important factor in the US. The exact contribution of fruits and vegetables is unclear, but vegetable oil does appear to play a role in human dioxin exposure. Inhalation and consumption of contaminated water and soil are not major sources of human exposure to TCDD. 

Occupational exposure to CDDs most likely occurs mainly through inhalation of CDD-contaminated particles or dust and through dermal contact with solutions containing CDDs. However, data indicate that oral exposure to low levels of CDDs from contaminated food (including milk) represents the major route of environmental exposure for the general population and for people living in areas with known dioxin contamination (Connett and Webster 1987 Schecter et al. 1994a Travis and Hattemer-Frey 1987). 

Other potential pathways of exposure-air inhalation, ingestion of water and soil, and dermal contact with soil-are much less significant to total daily intake of dioxins. PCDD/F intake via air inhalation, water ingestion and soil ingestion is estimated to be 3.2 pg TEQ d 1 (2-3% of total daily intake).38 Dermal contact with soil is negligible, however, constituting an estimated daily intake of 0.15pg TEQ d-1.38... 

The primary pathways for TCDD exposure appear to be inhalation and ingestion. Eating meat, fish, and dairy products makes up more than 90% of the intake of dioxins. Close proximity to an uncontrolled hazardous waste site or working in industries involved in producing pesticides containing dioxins can be sources of inhalation exposure for the general public and workers alike. Skin exposure can occur through contact with contaminated soils. 

Wolf N, Karmaus W. Effects of inhalative exposure to dioxins in wood preservatives on cell-mediated immunity in day-care center teachers. Environ Res 1995 68(2) 96 105. 

Cleanup Activities. Cleanup actions have focused on reducing potential exposure through inhalation or ingestion of dioxin-contaminated soils or dust. Many techniques have been developed and/or evaluated by the EPA Office of Research and Development ( ) and have been employed by OSWER and others in cleanup activities. 

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