How much health risk exists from dioxin in Food Grown for Human Consumption? [POSTER]

“Dioxin” refers to a group of persistent chlorinated chemical compounds that have similar chemical structures and toxicities, and are ubiquitous in the environment. Dioxins and furans are unwanted by-products of incineration, uncontrolled burning and certain industrial processes. Industrial sources of dioxin to the environment include incinerators, metal smelters, cement kilns, the manufacture of chlorinated organics, and coal burning power plants. Dioxin is also produced by non-industrial sources (now considered by the EPA to be the greatest source in the U.S.), like residential wood burning, backyard burning of household trash, oil heating, and emissions from diesel vehicles. Dioxin, as a general term, consists of two chemical groups, called polychloro-dibenzo-p-dioxins and polychloro-dibenzofurans. Of the 210 dioxin and furan cogeners, only 17 are considered to pose risk to human health.

In 2000, the EPA estimated that the lifetime cancer risk associated with the average person’s body burden of dioxin is between 1 in 1000 and 1 in 100. If true, this estimate of risk would represent a very significant public health concern. Routine monitoring of dioxin levels in foods or animal feed had not been conducted by the FDA, the EPA, or the FSIS until 1999 when the FDA’s Total Diet Study added Dioxin to the list of analyzed chemicals in its Market Basket Surveys. While efforts of the FDA, the United Nations, and others have monitored dioxin exposure, these efforts have shied from equating these exposures to health risk.

This poster uses food consumption data and dioxin exposure estimates from the Food and Drug Administration Total Diet Study to calculate the health risks of the US diet. Using the Superfund risk assessment methodologies, carcinogenic and non-carcinogenic health effects were estimated for several age group receptors in the general population. Risk calculations show that background dioxin concentrations in food can represent a significant contribution to total chemical risk in the US diet. These risk calculations can be used as estimates of contributions to total risk from background dioxins to aid in determining the extent of environmental remediation in an area suspected of a dioxin release.