Americans are likely polluted with far more pesticides than current studies report: The vast majority of pesticides that taint food have never been tested in people.
Agribusiness and pesticide companies are not required to test for their chemicals in people, not even for compounds that widely contaminate the food supply. The federal government’s national biomonitoring program, run by the CDC, has likely only scratched the surface of the full burden of pesticide pollution in people. EWG analysis shows that:
* • The CDC has tested Americans for only 32 of the 215 pesticides that government tests turned up on fresh fruits and vegetables since 2001 (not all of these have established residue tolerances on produce).
* The agency has tested people for only 9 of the 35 pesticides found on the greatest number of different fruits and vegetables (at least 15 types each).
* And it has tested for none of the 8 most commonly detected pesticides on fruits and vegetables (compounds tested more than 100 times since 2001, with an overall detection rate of at least 10 percent). These include pesticides found in apples, bananas, strawberries, and other widely consumed favorites.
Very little is known about the safety of real-world pesticide exposures; limited available studies point to increased risks for neurological damage in children.
Even when government research uncovers wide-scale pesticide pollution in body tissues of Americans, follow-up studies are not required or conducted to understand the implications of the exposures.
Industrial produce operators and pesticide interests have asserted that “There are no studies that specifically link pesticide residues in the diet with health effects.” Such studies are not required. The industry has confused an absence of data with proof of safety. They are two vastly different things.
Shoppers’ increasingly common decisions to avoid pesticides or to choose organics are backed by an extensive body of evidence demonstrating that pesticides harm workers, damage the environment, and demonstrate toxicity to laboratory animals. Pesticides are designed to be biologically active; they are designed to kill living organisms. EPA is directed to set standards for pesticides in food that allow a sufficient margin of safety between human exposures and amounts known to be harmful.
But the complexity of people’s diets, the variation in pesticide residues on foods, and the difficulty sorting out effects of pesticide mixtures from additional lifestyle, genetic and environmental factors contributing to diseases like cancer, birth defects, and behavioral problems, all make it difficult to be certain of the risks of pesticides in the diet.
Best studied are a group of neurotoxic pesticides known as organophosphates (OPs). Until strict cut-backs in their use in 2000 over health concerns, these chemicals were some of the most common pesticides in agriculture, accounting for about half of all insecticides used in the U.S. in 1999 (EPA 1999). Individual OP pesticides share a common chemical structure and toxic mechanism in the body. They damage nervous system function by blocking acetylcholinesterase. This enzyme is responsible for ending nerve cells firing—when blocked nerve cells fire continuously, acute poisoning or long-term nerve damage can result. Children are believed to be at higher risk for permanent effects from OP exposures, though neurotoxins can be harmful to people of any age.
EPA estimates that 40 percent of children tested in CDC’s national biomonitoring study from 1999 to 2002 had amounts of OPs in their bodies at levels exceeding standard margins of safety, relative to levels shown to be harmful in laboratory studies (Paynes-Sturges 2009).
In May 2010 researchers at Harvard University published research showing increased risk for ADHD in American children exposed to typical levels of OPs. Scientists analyzed the CDC’s biomonitoring data on OP pesticide exposure for 1,139 children 8 to 15 years old, tested from 2000 to 2004 (Bouchard 2010). They found that every 10-fold increase in dimethyl alkylphosphate (DMAP), an OP metabolite in the body, corresponded to a 55 to 72 percent increase in the odds of ADHD diagnosis. Effects of OPs were most pronounced among children with the hyperactive/impulsive subtype rather than a primarily inattentive ADHD. Because the NHANES study is carefully designed to be a representative sample of Americans, these results are considered generalizable to all American children.
The validity of the Harvard study is bolstered by studies of children more intensely exposed to OP pesticides. Two studies link prenatal OP exposures to increased risk of pervasive developmental disorders (Bouchard 2010 citing Rauh 2006, Eskenazi 2007). Minority children residing in New York City were at greater risk of attention problems, ADHD and pervasive developmental disorder if they had been born with greater concentrations of chlorpyrifos during pregnancy, as measured by umbilical cord blood concentrations at birth (Rauh 2006). New York City was previously an area of intense chlorpyrifos use. Between 72 and 85 percent of participants were exposed to this chemical in their homes during pregnancy, with half using higher risk applications. Children primarily from farmworker families in the Salinas Valley of California performed more poorly on standardized neurobehavioral tests when they were carried residues of dialkyl phosphates (OP metabolites) in their bodies in utero or during early life (Eskenazi 2007). Post-natal exposures to OPs are associated with behavioral problems, pervasive developmental disorder, poorer short-term memory and longer reaction times in studies of children living in agricultural regions of Ecuador and the United States (Eskenazi 2007, and Bouchard 2010 citing Grandjean 2006, Ruckart 2004, Rohlman 2005).
Evidence that everyday exposure to organophosphates may cause permanent effects on children’s brain and behavior is a sobering reminder of the need to safeguard children from harmful chemicals in their diets. Children are at increased risk for high OP exposure due to greater intake of fruits and vegetables than adults (when adjusting for their small body size) and because behaviors and increased hand-to-mouth activity lead to greater ingestion of contaminated dirt and dust. Studies in an agricultural region of California have shown that infants are more at risk to OP toxicity than older children and adults, because their detoxification systems for OPs are less developed. Furthermore, people with lower activity of a detoxifying enzyme known as PON1 are more susceptible to OP toxicity, with the most sensitive newborn 65 to 130 times more affected than the least sensitive adult (Furlong 2006, Holland 2006).
A 1993 report by the National Academy of Sciences evaluated children’s exposures to pesticides on foods and concluded that “infants and children differ both qualitatively and quantitatively from adults in their exposure to pesticide residues in foods” and that some children exceeded safe levels of pesticides in their diets (NAS 1993). Furthermore NAS clarifies that in addition to exposures from multiple foods, safety levels for pesticides account for drinking water contamination and household pesticides. The Food Quality Protection Act of 1996 mandated that EPA systematically review pesticide exposures and restrict the most harmful uses. Subsequent studies provide strong evidence that these policies, and shopper’s efforts to avoid contaminated produce are well justified.
Over the past 15 years EPA eliminated some major uses of OPs that accounted for the highest exposures in children, including home insecticides and some food uses, but children continue to be exposed to OPs that contaminate common foods.
Recently, researchers from Emory University in Atlanta, Georgia released findings on body burden levels of OPs in children, and reported that “this study demonstrate that dietary intake of OP pesticides represents the major source of exposure in young children” (Lu 2008).
Industry groups making claims of safety should be asked if they have tested to learn how much of their chemicals end up in people, including in cord blood, where pollution attests to in utero exposures during especially vulnerable times. They should also be asked what if any research they or others have conducted to discern potential health problems in children and other vulnerable populations exposed to higher but still “normal” amounts of their products.
Source: http://www.foodnews.org/reduce.php#3
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