Illegal poisons in US food

July 24, 1996

By Peter Montague

There are about 630 different "active ingredients" in pesticides worldwide. In real-world use, these main ingredients are combined with other chemicals (called "inert ingredients") to make several thousand toxic formulations — but the basic active ingredients number about 630.

The purpose of a pesticide is to kill living things by poisoning them, so it is no surprise that these 630 chemicals are all toxic. In many cases — especially the newer pesticides — they are very toxic. For example, the most commonly used insecticide is called chlorpyrifos (trade name: Dursban). Dursban attacks the central nervous system so effectively that six grams are sufficient to kill an adult human.

To be used legally in the US on fruits and vegetables, pesticides must be registered with the Environmental Protection Agency (EPA).

Under common law, putting poisons into your neighbour's well, or onto your neighbour's food, is considered very antisocial and is strictly illegal. However, after the manufacturer of a pesticide applies for a pesticide registration, for a fee the government (specifically, Congress) sells them the right to put poisonous residues on food.

When a pesticide is registered for use on fruits or vegetables, a "tolerance level" for that pesticide on that crop is set by EPA. The "tolerance level" is the amount of toxic residue that can legally remain on the crop when the consumer eats it.

According to the National Academy of Sciences, "Tolerance levels are not based primarily on health considerations ... Their primary purpose is to ensure compliance with good agricultural practice." In other words, the first concern in setting a tolerance is to allow enough of the pesticide to be used to kill the target pests. Health is secondary.

After a tolerance level is set, EPA later (often years later) may set a "reference dose" (called an RfD) that the agency considers safe for consumers to eat. As a result of this peculiar process, EPA has set many "tolerances" at levels far higher than the references doses that EPA has declared safe. In other words, EPA has set legal pesticide residue limits for many poisons on many fruits and vegetables that are higher — in some cases much higher — than the level the EPA considers safe.

For example, EPA's tolerance for dimethoate is 64 times as high as the "safe dose" (the RfD) for dimethoate. EPA's tolerance for methyl parathion is 41 times as high as the RfD. EPA's tolerance for endosulfan is 24 times as high as the "safe" (RfD) dose for endosulfan.

Furthermore, RfDs are set to protect adults, not children. The EPA has never set an RfD or a tolerance based on children's health. When the National Academy of Sciences studied pesticides and children's health in 1993, it concluded, "A fundamental maxim of pediatric medicine is that children are not 'little adults' ... In the absence of data to the contrary, there should be a presumption of greater toxicity to infants and children."

The Academy specifically recommended that tolerances should be reduced 10-fold to protect children: "The committee recommends that an uncertainty factor up to the ten-fold factor ... should be considered when there is evidence of postnatal developmental toxicity and when data from toxicity testing relative to children are incomplete."

Data from toxicity testing relative to children are incomplete in the case of every pesticide currently in use. Researchers who reviewed the pesticide literature in 1995, specifically looking for information about children, wrote in December, "Thus major gaps exist in our knowledge of the health effects of chronic pesticide exposures to children. No published studies have examined the neurotoxic effects of low-level pesticide exposure to children."

Thus if the National Academy's recommendations were to be carried out, all pesticide tolerances would have to be reduced by a factor of 10. However, since the release of the Academy's report in 1993, no tolerances — not one — for pesticides in food have been adjusted in any way to protect infants and children.

It seems safe to say, therefore, that no legal levels of pesticides can be considered safe for children, and many legal levels of pesticides are clearly not safe even for adults.

Furthermore, the pesticide control system in the US was established to maintain pesticide residues on food not at "safe" levels but at or below "tolerance levels". EPA sets tolerance levels, and then the Food and Drug Administration (FDA) tests samples of food to see if the tolerance levels have been illegally exceeded. How well does this system work?

Researchers with the Environmental Working Group (EWG) in Washington, DC, looked carefully at the FDA's pesticide residue control system in 1995 and published an excellent report. Here is what they found:

The FDA takes samples of food and tests them in FDA laboratories. The results of those tests are then entered into a computer.

However, the legal "tolerances" for those pesticides on those crops have never been entered into a computer, so the computerised test data must be compared to existing tolerances by technicians using pencil and paper. If those technicians find that a tolerance has been exceeded, or an unregistered pesticide has been detected, they are supposed to report it to FDA's enforcement division. Unfortunately, the EWG's analysis revealed that, because of careless pencil-and-paper techniques — or perhaps because they simply ignore illegal pesticides — FDA chemists fail to report 43% of all the violations they find.

Some foods are extraordinarily contaminated with illegal pesticides. For example, 24.7% of all peas contain illegal pesticides and 15.7% of all pears contain illegal pesticides. Some 12.5% of apple juice contains illegal pesticides, 12.4% of blackberries and 11.7% of green onions. These illegal pesticides occur in addition to the legal pesticide residues that routinely contaminate food supplies.

All together, FDA claims that only 3.1% of fruits and vegetables in US grocery stores contain illegal pesticides. However, the report reveals, based on analysis of FDA's own monitoring data, that 5.6% of food on grocers' shelves — contains illegal pesticides. A person eating five fruits and vegetables a day will be eating illegal pesticides 75 times a year.

Even this is probably a gross underestimate of the problem. In 90% of cases, FDA laboratories use pesticide-measuring techniques that can detect only half of the pesticides currently in use. Monitoring techniques that can detect the remaining half are very expensive and are not routinely used.

For this and other reasons described in the FDA report, we estimate that about 13% of US fruits and vegetables may contain illegal pesticide residues in addition to whatever legal pesticide residues they may contain. If the 13% figure is correct, then someone eating five fruits and vegetables a day would eat illegal pesticides 174 times a year.

What happens to the 3.1% of fruits and vegetables that FDA says contain illegal toxic pesticide residues? Government studies show that 100% of the domestic portion is sold to consumers, and 60% of the foreign portion is sold to consumers. The system does not protect consumers even when it identifies illegal pesticides.

It seems clear that the pesticide monitoring and enforcement system in the US is broken. In truth, it has been broken for many years. This is certainly not news to Congress, which (with the advice and consent of the food corporations) created the system to begin with.

The General Accounting Office has published 22 reports since 1980 describing the many ways in which the pesticide control system fails to protect consumers. Congress has consistently refused to make any changes. We can only conclude that Congress prefers the system the way it is. Or, more precisely, the food industry prefers the system the way it is, and Congress is not able to break free from the steely grip of moneyed corporations.
[From Rachel's Environment & Health Weekly.]