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Are pesticides posing intolerable risks?

Are pesticides posing intolerable risks?

The Truth about "Poisoned" apples
Panic in the Produce Aisle
But are Children Taken into Account?
On the Handling of Fruits and Vegetables How organic farming fits into the picture

"Our nation's children are being harmed by the very fruits and vegetables we tell them will make them grow up healthy and strong. These staples . . . routinely, and lawfully, contain dangerous amounts of pesticides, which pose an increased risk of cancer, neurobehavioral damage, and other health problems. . . . Little is being done by the government to protect children from the intolerable risk to their health posed by pesticide residues in food." So begins a report released by a nonprofit organization known as the Natural Resources Defense Council, one of whose most startling claims is that a chemical currently allowed on apples and in apple juice and applesauce creates an unacceptable cancer risk in and of itself.

The widely publicized release of that report early this year, followed by the government's announcement that more than 2 million crates of imported fruit were being detained because of the discovery in a Philadelphia port of two Chilean grapes laced with cyanide, threw Americans into a panic about the safety of our food supply.

The dust stirred by those incidents has only now begun to settle. And some tough questions remain. Is our food supply safe? Is it risky to eat an apple a day -- or a grape, peach, or pear for that matter? Is the government doing an adequate job of protecting consumers?

The truth about 'poisoned' apples

Earlier this year a segment of the television program "60 Minutes," picking up on the statements put out by the Natural Resources Defense Council, delivered some disturbing information to Americans. Apples and apple products treated with the chemical Alar, it reported, pose an intolerable risk of cancer, particularly to children and infants who consume large amounts of apple juice and other apple-based foods. Understandably, the public reacted with alarm. Many school systems banned all sorts of apple goods from their menus. And sales of fresh apples dropped 20 percent.

Ironically, despite the sudden attention accorded Alar (generic name daminozide), the controversy surrounding its safety is actually 12 years old. In 1977, almost a decade after apple growers started spraying orchards with that chemical to keep apples from falling off trees before they were fully ripe as well as to increase their storage life and enhance their red color, scientists raised the concern that it may cause cancer in animals. They also said that the heat process used to make apple juice or applesauce causes daminozide to break down into a substance called UDMH, which is believed to be an even more potent carcinogen than Alar itself.

In 1985, after an intensive review of daminozide's risks and benefits, the Environmental Protection Agency announced its plan to ban use of the chemical because it presented an unreasonable risk to consumers. That same year, however, an independent Scientific Advisory Panel created by Congress said the animal studies used to support the ban were flawed, thereby necessitating completion of more reliable studies before Alar could legally be taken off the market.

The EPA then initiated new studies on daminozide. And to help keep consumers safe while waiting for the results of the studies, it tightened the limits for residues of the chemical allowed in apples. Not surprisingly, that move offered little comfort to the parents of small children several months ago when the Natural Resources Defense Council declared that the risk of developing cancer incurred by eating foods contaminated with UDMH from birth to age five is 240 per million. That's 240 times higher than the one-in-a-million chance (over the course of an entire lifetime) deemed acceptable by the EPA.

But there are some hitches in the numbers, says the EPA, not the least of which is that the council's alarming claims are based on the flawed data rejected by the congressional advisory panel back in 1985.

That's not to say that UDMH doesn't pose potential risks to consumers. Just last May, in fact, the EPA proposed banning daminozide use once and for all, based on new preliminary data suggesting that UDMH does present unreasonable risks. Nevertheless, the agency claims that while UDMH may now be said more conclusively to contribute to the chance of developing cancer, the hazard is not even remotely as high as the council alleges. Indeed, the EPA estimates that the cancer risk arising from an entire lifetime of eating foods containing UDMH is, at most, 50 persons per million -- still too many, but not nearly as many as the public has been led to believe.

The final, definitive evidence on which the EPA can legally base a total ban will not be ready until January 1990. If the new evidence does confirm its suspicions, Alar use will be canceled within 60 days, before the start of the next apple growing season.

What's an apple-eating consumer to do in the interim? First, be aware that in response to public pressure, the company that produces Alar, Uniroyal, has agreed to stop selling the chemical for use on all domestically grown apples. Second, keep in mind that chief officials not only at the Environmental Protection Agency but also at the Food and Drug Administration and the U.S. Department of Agriculture say there is no imminent hazard posed to children who consume apples and apple products at this time. Even if UDMH is proven unequivocally to be cancer-promoting over the long term, the EPA estimates that the risk that can be incurred in the year or so before it can be officially banned is, at most, one in a million for adults and four in a million for children. Thus, even though a risk exists, it's not enough to warrant avoiding apples and apple products. (To help put the matter into perspective, almost 200 out of every million Americans were killed in auto accidents in 1986 alone.)

Panic in the produce aisle

For many consumers, Alar was the bad apple that spoiled the whole bunch, so to speak. That is, concern over the risks of eating apples and apple products tainted with the chemical raised the broader question of whether any produce stocked in the supermarket is safe to eat. That uncertainty has been fueled by newspaper and magazine articles shaped around the Natural Resources Defense Council's prediction that as many as 6,200 preschoolers may develop cancer at some time in their lives as a result of eating produce contaminated with chemical pesticide residues.<P> But that number and others like it are estimates based on experiments with animals, not foregone conclusions. "When you take experiments on mice and extrapolate them to humans," says F. Jack Francis, PhD, an expert in food safety at the University of Massachusetts, "it's going to be a judgment decision that can be slanted either up or down." Indeed, Dr. Francis adds, it's impossible for scientists to state definitively that chemical X will cause Y cases of cancer.

Moreover, the mere presence of pesticide residues in a food does not necessarily mean the food is harmful. With today's advanced technology, scientists can find amounts as tiny as one part per trillion -- a level so low it may not have any biological significance. "What must be emphasized is that the dose makes the poison," says Bruce Ames, PhD, director of the National Institute of Environmental Health Sciences. Even though a particular chemical may cause tumors when given to laboratory rats or mice at levels hundreds or thousands of times higher than what humans ingest through food, its presence in the food supply in comparatively minuscule amounts may cause virtually no harm. The point becomes particularly clear when you consider that even the naturally occurring toxins in most plant foods have been shown to cause cancer in rats or mice when they were fed to them in large enough doses. In fact, says Dr. Ames, a naturally occurring carcinogen in mushrooms may be even more hazardous to health than apple juice that contains the daminozide derivative UDMH. He even goes so far as to say that the risks incurred from drinking six ounces of apple juice that contain UDMH are less than the risks involved in eating just one mushroom. He estimates, too, that we take in close to 10,000 times more "natural pesticides" than synthetic ones.

Of course, the federal government can't control Mother Nature. But it does set limits for manmade pesticides. And the Food and Drug Administration, the arm of the government responsible for monitoring pesticide residues in raw agricultural products, reports that in 1987 dietary intake of pesticides was only a small fraction of what is considered acceptable. What's more, after analyzing for more than 250 chemicals in some 14,500 food samples -- more than half of which were imported from other countries -- the agency found no residues whatsoever on 57 percent of them. And less than one percent contained levels that exceeded the government's tolerance limits.

To be sure, the system is not without its limitations. Even the EPA's acting deputy administrator, Dr. John Moore, acknowledges that more accurate monitoring of data on pesticide residues and more effective laws for getting hazardous pesticides off the market quickly are in order. Likewise, FDA Commissioner Frank Young admits there are lapses in surveillance and sampling of foods that need to be corrected.

Nevertheless, says an agency spokesperson, "even if we had a budget the size of the Pentagon's, we still would never be able to provide the public with a 100 percent guarantee of safety." There simply is no way that every single piece of food eaten by every American can be checked. In the meantime, positive changes are being made. The FDA, for example, is increasing the number of food samples it tests annually. And the Environmental Protection Agency, which sets the tolerance levels that the FDA tries to enforce, is currently in the process of reevaluating the risks and benefits of the pesticides used most widely.

But are children taken into account?

Some groups are concerned that in setting legal limits for pesticide residues in foods, the EPA does not consider the eating habits or particular vulnerabilities of growing children. The Natural Resources Defense Council, for example, argues that since children eat more fruit for their weight than adults, they are exposed to proportionately higher levels of pesticide residues. It also alleges that youngsters "may be more susceptible to the toxic effects of these pesticides as a result of their immature physiological development."

The EPA counters that its methods of setting pesticide residue limits is "highly protective" of both adults and children. For one thing, the experiments the agency uses to estimate the levels of pesticides that can safely be ingested use young animals and then follow them through adulthood, thereby mimicking as much as possible a human's exposure to a pesticide over the course of a lifetime. In addition, the EPA compensates for the uncertainties inherent in extrapolating the results of animal experiments to humans, as well as for the possible differences in sensitivities in particular groups such as infants, by incorporating a hundredfold safety factor into the limits set for most pesticides. What that means is that the government determines the smallest concentration of a pesticide that can cause adverse effects in animals and then allows foods to contain no more than one one-hundredth of that level. Admittedly, such methods have built-in imprecisions. But the government is working hard to minimize them. Since 1988, in fact, the EPA has been funding a study conducted by the National Academy of Sciences to examine current testing methods as well as to develop even better ways for assessing the risks to children.

It should be noted, too, that although many people automatically assume children are more vulnerable than adults to the hazards posed by pesticides, not all the evidence needed to support that theory is in. "You can't say that kids are more sensitive to pesticides across the board," says Donald Mattison, MD, vice-chairman of the National Academy of Sciences' Committee on Pesticides in the Diets of Infants and Children. It's true that when a chemical gets into the rapidly growing and multiplying cells of a child it is more likely to affect health adversely than it would in an adult's cells. But as Dr. Mattison points out, some substances must be metabolized by the body before they become toxic. And since some children appear to have less active metabolisms than adults, he adds, they could be relatively protected from certain toxic effects.

Small consolation, perhaps, to parents of little ones. But those who are particularly concerned would do well to know that pesticide residues actually found in infant, toddler, and junior foods are minimal. In fact, of the several thousand samples of infant foods analyzed over the last 25 years, including formula, cereal, fruits and fruit juices, vegetables, and desserts, only about one out of every four items had detectable residues, none of which exceeded government standards. In addition, after collecting more than 200 food samples from four areas of the country, preparing them, analyzing them, and calculating daily intake of detected residues for infants, toddlers, and teenage children, the FDA found dietary intakes to be far below accepted U.S. limits. Furthermore, they came to less than one percent of the intakes deemed acceptable by the World Health Organization and the United Nations' Food and Agriculture Organization.

The bottom line is that both children and adults are being urged to eat their fruits and vegetables, and that's likely to lead to greater ingestion of herbicide and pesticide residues. But as the National Research Council spells out in a recent Diet and Health report, "the potential small increased risk . . . that might result from increased exposures in the general population would be greatly outweighed by the potential benefits (i.e., reduced risk of cancers of the lung, stomach, colorectum, and other sites and reduced risk of other chronic diseases) to be expected from greater fruit and vegetable consumption."

Indeed, death rates from all cancers except smoking-related lung cancer have been declining for all age groups under age 85 since the '50s -- the decade when pesticide usage began escalating.

On the handling of fruits and vegetables

  • Wash produce in detergent.
  • Peel all fruits and vegetables.
  • Buy only organic.
  • Beware of perfect-looking products.
These are just a smattering of the warnings now reaching consumers through newspapers, magazines, radio, and television. But can such measures really do anything useful for you and your family? Or is all the advice just part of the "chemophobia" that has hit the nation? What follows are some of the most commonly heard tips along with a perspective that will help you decide how closely you ought to be following them.

Go "organic." One of the problems with that advice is that there is no federal definition for "organic," so you have no surefire way of knowing whether food that is labeled as such is truly free of pesticides, herbicides, and fungicides. Even honest marketers of fruits and vegetables labeled "organic" may inadvertently be selling produce that contains traces of pesticides. That's because pesticide residues can remain in soil for years and can be blown by the wind from pesticide-sprayed fields to crops grown without chemicals.

Buy from supermarkets that test for pesticide residues. Some grocery chains are now having their fruits and vegetables analyzed by labs so they can assure consumers with certainty that the food in their produce aisles is pesticide-free. But test results can vary from lab to lab. In addition, while some methods of analysis allow scientists to detect pesticides at a level of, say, one part per million, others can find traces as small as one part per billion or trillion, an insignificant amount from a public health viewpoint. Thus, depending on store policy and on who is doing the analyses, the results can add to rather than clear the confusion -- not to mention drive up the price of produce to cover testing costs.

Wash produce with soap. Of course, all fresh fruits and vegetables should be rinsed thoroughly to remove any soil and/or other dirt and bacteria that may have come into contact with the food during shipping and handling. But advising consumers to wash produce with dishwashing detergent or soap is "an unwise recommendation," says Ron Gardner, an extension associate with Cornell University's Chemicals-Pesticides Program. Soap residues may not be washed off thoroughly enough, and "we know less about the health effects of ingesting soap than we do about taking in pesticides."

Peel it. There's a double-edged message in that advice. On one hand, since many chemicals remain on the surface of plants to which they are applied rather than penetrate the inside, peeling a fruit or vegetable could decrease the levels of pesticide residues that make their way into the body. Removing the peel from a cucumber, for instance, might decrease the ingestion of fungicides, which are often mixed with wax that gives cucumber peels their shiny appearance. On the other hand, much of the fiber and nutrients in fruits and vegetables concentrate in and just under the peel. Thus, making a habit of peeling all produce all the time will substantially lower the intake of substances that can enhance health and perhaps protect against disease.

Pass up perfect-looking produce. Some people are under the impression that if an item looks "too good," it must have been treated with large amounts of pesticides. Not true. To be sure, chemicals do help fruits and vegetables stay fresh longer and look better. But a "perfect" vegetable or piece of fruit can also be the result of a particularly good growing season or the product of a high quality breed of plant. So "beware perfect produce" hardly serves as a sensible rule of thumb.

How organic farming fits into the picture

Most experts agree that the use of pesticides to grow fruits and vegetables not only poses minimal health risks but also is the very practice that, helps farmers provide the country with the abundant food supply it now enjoys. When it comes to protecting the environment, however, the advantages of raising produce without the use of pesticides, herbicides, and chemical fertilizers are clear. Nonchemical, or organic, farming helps preserve wildlife that might otherwise be harmed by the substances applied to crops. By the same token, it helps safeguard farm laborers and people who live near farms from exposure to greater concentrations of potentially toxic chemicals than the rest of the population. In addition, organic farming methods prevent the possibility that pesticides and chemical fertilizers will make their way through the soil and contaminate bodies of water beneath the ground that serve as the main water supplies in most rural areas. Finally, organic farmers rotate their crops in such a way as to help preserve the quality of the soil from year to year as well as reduce soil losses.

Given all these advantages, it may well be asked why an immediate mass shift is not made from conventional to organic farming techniques. One reason is that, at least in the short run, such an abrupt switch would diminish the quantity and variety of the food supply dramatically and drive up prices concomitantly. The country, as a whole, is set up for conventional farming and could not change:techniques overnight. In addition, even those experts who strongly support the organic movement point out that it is impossible to predict whether farmers can provide an adequate food supply by relying entirely on organic farming methods.

Still, "a partial move in that direction clearly would be beneficial," says William Lockeritz, PhD, a research associate professor at Tufts University who specializes in exploring environmentally sound agricultural methods. But, by itself, buying organic produce in the grocery store is not likely to play a significant role in influencing the organic movement, he adds. Farmers are still apt to remain hesitant about making the change because they are uncertain about what it would do to their profit margins over the long term. In addition, they may not have easy access to the technical know-how needed to shift over, since so few farmers are currently using organic methods. Finally, government programs that subsidize farmers are geared toward financing those who use conventional rather than other farming techniques. Until more financial incentives and educational resources are made available, there is little possibility for conventional farmers to make an easy switch.

Source: Diet & Nutrition Letter, Tufts University, Vol.7, No.6, 1989