Study concludes potentially harmful pesticides pass from food to children
February 1, 2008
Results of year long study found children who ate a variety of conventional foods also ingested measurable and concerning amounts of organophosphates, widely used chemicals that kill insects by disrupting their brains and nervous systems.
When the same children ate organic fruits, vegetables and juices, signs of pesticides were not found.
“Once you switch from conventional food to organic, the pesticides (malathion and chlorpyrifos) that we measured in the urine disappeared. The level returns immediately when you go back to the conventional diets,” said Lu, a professor at Emory University’s School of Public Health and a leading authority on pesticides and children.
Lu points out that there is no certainty that the pesticides measured in this group of children would cause any adverse health outcomes. However, he added that a recent animal study demonstrated that persistent cognitive impairment occurred in rats after chronic dietary exposure to chlorpyrifos.
Death or serious health problems have been documented in thousands of cases in which there were high-level exposures to malathion and chlorpyrifos. But a link between neurological impairments and repeated low-level exposure is far more difficult to determine.
“There’s a large underpinning of animal research for organophosphate pesticides, and particularly for chlorpyrifos, that points to bad outcomes in terms of effects on brain development and behavior,” Dr. Theodore Slotkin, a professor of pharmacology and cancer biology at Duke University in North Carolina, said in the April 2006 Environmental Health Perspectives.
Lu says more research must be done into the harm these pesticides may do to children, even at the low levels found on food. “It is appropriate to assume that if we — human beings — are exposed to (this class of) pesticides, even though it’s a low-level exposure on a daily basis, there are going to be some health concerns down the road,” he said.
The EPA says it eliminated the use of organophosphates on many crops and imposed numerous restrictions on the remaining organophosphate pesticide uses.
“As a result, the amount of these pesticides used on kids’ foods (has undergone) a 57 percent reduction,” said Jonathan Shradar, the EPA’s spokesman.
But that’s not nearly enough to prevent birth defects and neurological problems, said Chuck Benbrook, chief scientist of the Organic Center, a nationwide, nonprofit, food research organization.
“The pesticide limits that EPA permits are far, far too high to say they’re safe. And, the reduction that EPA cites in the U.S. has been accompanied by a steady increase in pesticide-contaminated imported foods, which are capturing a growing share of the market,” he said.
Yet the EPA continues to insist that “dietary exposures from eating food crops treated with chlorpyrifos are below the level of concern for the entire U.S. population, including infants and children.”
That statement is “not supported by science,” Benbrook said. “Given the almost daily reminders that children are suffering from an array of behavioral, learning, neurological problems, doesn’t it make sense to eliminate exposures to chemicals known to trigger such outcomes like chlorpyrifos?” he asked.
“Consumers,” Lu says, “should be encouraged to buy produce direct from the farmers they know. These need not be just organic farmers, but conventional growers who minimize their use of pesticides.”
Understanding how fruits and vegetables grow can help guide the consumer, he says. For example, organic strawberries probably are worth the money because they are a tender-fleshed fruit grown close to the dirt, so more pesticides are needed to fight insects and bugs from the soil. He adds apples and spinach to his list. “It may also be money-smart to choose conventionally grown broccoli because it has a web of leaves surrounding the florets, resulting in lower levels of pesticide residue,” Lu says.
Chlorpyrifos, made by Dow Chemical Co., is one of the most widely used organophosphate insecticides in the United States and, many believe, the world.
For years, millions of pounds of the chemical insecticide were used in schools, homes, day care centers and public housing, and studies show that children were often exposed to enormously high doses. Just as the EPA was ready to ban the product, which analysts said would have damaged Dow’s overseas sales, the company “voluntarily” removed it from the home market. Yet, with few exceptions, the agricultural uses continued.
Sources: http://www.ehponline.org/members/2008/10912/10912.pdf, http://www.atsdr.cdc.gov/tfacts154.html#bookmark02, http://www.atsdr.cdc.gov/tfacts84.html#bookmark02, http://en.wikipedia.org/wiki/Organophosphate