Eating organics cuts kids' pesticide loads
A recent American study at the University of Washington analysed pesticide breakdown products (metabolites) in pre-school aged children and found that children eating organic fruits and vegetables had concentrations of pesticide metabolites six times lower than children eating conventional produce. The study compared metabolite concentrations of organophosphorus (OP) pesticides (a class of insecticides that disrupt the nervous system) in the urine of 39 urban and suburban children aged 2 to 4 years. The researchers' findings point to a relatively simple way for parents to reduce their children's chemical loads--serve organic produce.
While the researchers found median concentrations of OP metabolites six times lower in the children with organic diets, average concentrations for the organic group were actually nine times lower, suggesting that some children eating conventional produce had much higher concentrations of OP metabolites in their systems.
Young children are at risk from acute poisoning through these organophosphate residues in their food, an earlier analysis by the US National Research Council has shown. Analysing just five pesticides and eight foods, they calculated that two-year-olds could exceed the Acceptable Daily Intake of one particular organophosphate (chlorpyrifos) 4.1% of the time.
In New Zealand, independent health researcher Alison White has calculated that young children here could be taking in more than 20 times the levels of organophosphates compared to young US children. She calculated the estimated daily intake of five organophosphate pesticides in 1-3 year olds according to data from the Ministry of Health Total Diet Survey of 1997/98, and compared this to similar data from the US Total Diet Surveys.
"The good news", Ms White reported, "is that parents of young children can dramatically lower this risk of organophosphate poisoning by giving them organic food, and especially avoiding conventional food which is known to have high organophosphate residues in New Zealand such as bread, pears, apples, nectarines, tomatoes, cucumber and lettuce."
Ms White states: "We have been concerned for a long time about continuous exposure to organochlorine pesticides because they persist in our bodies for years. This study reveals that we are continuously exposed to OP pesticides, not because they necessarily linger in our bodies, but because we are persistently being exposed through the food we eat every day."
The conclusion that small children may be exceeding "safe" levels of pesticide exposure is information that regulators should act on and, at the very least, reduce uses of these pesticides on food crops.
Researcher, Safe Food Campaign
(04)476 8607, (021) 1699 120.
Further information about the study
The authors focused on children's dietary pesticide exposure because children are at greater risk for two reasons: they eat more food relative to body mass, and they eat foods higher in pesticide residues -- such as juices, fresh fruits and vegetables. An earlier study cited by the authors looked at pesticide metabolites in the urine of 96 urban and suburban children and found OP pesticides in the urine of all children but one. The parents of the child with no pesticide metabolites reported buying exclusively organic produce.
Researchers recruited children for the study outside of conventional and organic grocery stores in the Seattle metropolitan region and asked parents to record all food consumed in a three-day period prior to collecting their child's urine over the next 24 hours. Based on the food diaries, the study assigned the children into groups consuming at least 75% organic or at least 75% conventional fruits and vegetables. Parents were also asked about household pesticide use in their homes and on gardens, lawns and pets. Although the authors found that parents of children eating conventional diets were more likely to report some home pesticide use, they did not find significant differences in concentrations of pesticide metabolites based on this use.
The children's urine was tested for five metabolites of OP pesticides which are registered in the U.S. and frequently applied to food crops. The study focused on these pesticides because they are metabolized into several easily recognizable compounds. Breakdown products of pesticides such as malathion, azinphos-methyl, parathion, oxydemeton-methyl, phosmet, methyl parathion, methidatihon and dimethoate were found at the highest concentrations. Of these pesticides, azinphos-methyl and phosmet are the two primarily used on fresh produce within the U.S. Lower concentrations were found of breakdown products from diazinon and chlorpyrifos.
Because many of the OP pesticides break down into identical metabolites, the study did not provide information on the specific pesticides children were exposed to. However, the study did determine that some children were at risk for consuming more OP pesticides than the U.S. Environmental Protection Agency (EPA) considers "safe" as a daily dose. The researchers concluded that organic fruits and vegetables can reduce exposure levels from above to below EPA chronic reference doses, "thereby shifting exposures from a range of uncertain risk to a range of negligible risk."
Ministry of Health (2000): 1997/98 New Zealand Total Diet Survey.
FDA (1993): Pesticide Program: residue monitoring 1992, J AOAC International 76.
NRC (1993): Pesticides in the diets of infants and children. Washington: National Academy Press.
PANUPS 31st January 2003 www.panna.org
Organophosphorus pesticide exposure or urban and suburban pre-school children with organic and conventional diets, Cynthia L. Curl, Richard A. Fenske, Kai Elgethun, Environmental Health Perspectives, October 13, 2002, National Institute of Environmental Sciences, EHP Online, www.ehponline.org
Do You Know What You're Eating? February 1999, Consumers Union of United States, Inc, www.consumersunion.org/food/do_you_know2.htm
Pesticide residues in conventional, IPM-grown and organic foods: Insights from three U.S. data sets, Food Additives and Contaminants, May 2002, www.consumersunion.org/food/organicsumm.htm