The Environmental Protection Agency missed a deadline this week to release part of an analysis on the public health impact of dioxins, a lapse that angered public health and environmental advocates.
After many years of delays, the agency said in August it would complete the first part of the dioxin reassessment, which would have set a toxicological threshold for the first time, by January 31.
The draft reassessment has been sharply criticized by the food industry for being too restrictive and being based on shaky science. Health and environmental groups expressed outrage at the continued delay.
“Shame on EPA Administrator Lisa Jackson for denying parents the information they need to protect their children from the health impacts of dioxin,” said Lois Marie Gibbs, executive director of the Center for Health, Environment & Justice, a group among dozens pressuring EPA on the issue. “This is America — parents have the right to know.”
Dioxins are released into the air during certain industrial processes, like cement production and are also naturally occurring. According to new government data, air releases of dioxin rose 10 percent between 2009 and 2010. Dioxins are ingested by food animals, via grazing and contaminated feed, and are bioaccumulated — a reality that has concerned regulators and public health authorities because dioxins are linked to reproductive and developmental problems, immune system damage and cancer.
The World Health Organization (WHO) estimates that 90 percent of human exposure to dioxins is via food, particularly meat, dairy, fish and shellfish. The food industry worries that the EPA reassessment would have recommended an exposure threshold that is lower than the level of exposure many Americans already face through their daily diet.
In December, the Food Industry Dioxin Working Group (FIDWG) — an ad hoc coalition made up of groups like United Egg Producers, the American Farm Bureau and the American Frozen Food Institute — sent a letter to a senior White House policy adviser expressing “deep concern” over the effort. The letter was also sent to key officials at the EPA, U.S. Department of Agriculture, Food and Drug Administration, Health and Human Services, and the White House Office of Management and Budget.
The EPA’s acceptable level for dioxin exposure, otherwise known as a reference oral dose (RfD), is expected to be .7 picograms per kilogram of body weight per day. Similar thresholds set by the World Health Organization and the European Union are between 1-4 picograms per kilogram of bodyweight per day.
If EPA finalized an RfD for dioxin it would not be a regulatory action, but it could be used as the basis for future regulation and would likely fuel some people to alter their dietary choices.
As the food industry pointed out recently in a letter to the Obama administration, some common food items could easily put someone over the draft RfD.
“Under EPA’s proposal…nearly every American – particularly young children – could easily exceed the daily RfD after consuming a single meal or heavy snack,” according to the industry groups. “The implications of this action are chilling. EPA is proposing to create a situation in which most U.S. agricultural products could arbitrarily be classified as unfit for consumption. The impact on agricultural production – conventional, organic, livestock/poultry/dairy, fruits, grains and vegetables – may be significant, as will be the loss of trade markets, all without evidence of additional health protection.”
The American Chemistry Council, which represents chemical companies, says that EPA needs to take more time to ensure the reassessment is based on sound science, and claims that the agency is “ignoring the most recent peer-reviewed science.” Many lawmakers and advocates say the reassessment is years overdue and that further delays are the result of undue influence of industry.
Just how long has this reassessment been in the works? EPA first began work on assessing the risks of dioxin exposure in the 1980s. The most recent human health reassessment was submitted by EPA to the National Academy of Sciences (NAS) in 2003, during the Bush administration. In 2006, NAS submitted recommendations to EPA on the reassessment. In May 2010, the agency released a draft reanalysis and the agency says it’s working expeditiously to get a final guidance out, but major industry opposition remains.
“The American public has been waiting for the completion of this dioxin study since 1985 and cannot afford any further delays,” Rep. Edward Markey (D-MA) said a letter to EPA this month to urge the agency to meet its deadline. “Despite worldwide agreement about the toxicity of these chemicals and their persistence in the environment, EPA has yet to release its findings on how dangerous these chemicals are to public health.”
According to CDC, dioxins and polychlorinated biphenyls (PCBs) have a similar toxicity.
“Human health effects from low environmental exposures are unclear,” says CDC on its resource page. “People who have been unintentionally exposed to large amounts of these chemicals have developed a skin condition called chloracne, liver problems, and elevated blood lipids (fats). Laboratory animal studies have shown various effects, including cancer and reproductive problems.”
For more information on dioxin exposure, see FDA’s resource guide here.