(Beyond Pesticides, October 4, 2012) The Centers for Disease Control and Prevention (CDC) has released updated tables for its Fourth National Report on Human Exposure to Environmental Chemicals, which was released in 2009. The new data includes updated tables for 119 chemicals and tables for 34 new chemicals, including updates for 2,4-D and triclosan and their metabolites. New metabolites of organophosphorous insecticides are added for the first time.
Notably, the report found that concentrations of four metabolites of organophosphates generally increased among nearly all groups CDC measured, while levels for two generally decreased. Organophosphate pesticides, such as chlorpyrifos, are highly toxic to humans and the environment. Chlorpyrifos is a frequent water contaminant and a long range toxicant, exposing communities and polluting pristine areas far from where it was applied. Volatilization drift â€”the evaporation of the pesticide after applicationâ€” is also part of the problem for chlorpyrifos. A 2009 study found the pesticide to have significant impacts on the growth and development of amphibians miles away from the site where it was first applied. A USGS study in 2007 concludes that the breakdown products of chlorpyrifos are up to 100 times more toxic than the original.
The Updated Tables, September 2012, present data from the 2005-2006, 2007-2008, and 2009-2010 survey periods and data for a few chemicals from the 2003-2004 survey period. The Updated Tables are cumulative and include data reported in earlier updates. This publication is the most comprehensive assessment to date of the exposure of the U.S. population to chemicals in our environment. CDC measures chemicals in peopleâ€™s blood and urine. The data analyzed in the Fourth Report are based on blood and urine samples that were collected from approximately 2400 people who participated in CDCâ€™s National Health and Nutrition Examination Survey (NHANES) from 2003 through 2004. NHANES is an ongoing national health survey of the non-institutionalized U.S. population that includes collecting and analyzing blood and urine samples to help further research involving exposures and health effects.
The types of exposure information found in the report can help physicians and public health officials determine whether people have been exposed to higher environmental chemicals as well as help scientists plan and conduct research about health effects. Much of the information has been previously published, but this is the first publication of all the data in one place. The report does not provide new health effects information. Research separate from that compiled in the Fourth Report is needed to determine whether higher levels of environmental chemicals in blood or urine are related to health effects.