Fruits and vegetables are essential to a healthy diet--in fact, no fewer than five servings a day is what the Food and Drug Administration (FDA), the U.S. Department of Agriculture (USDA), and the American Cancer Society recommend. The benefits of eating fresh produce for reducing certain types of cancer and heart disease are undisputed.

What is in question are whether consumers should be concerned about the effects of pesticides used in agriculture and the residues that may remain on conventionally grown produce purchased by consumers.

According to the Maryland-based Environmental Research Foundation, over the last 50 years, roughly 630 types of active ingredients in pesticides have been introduced into the environment. During this same period, the U.S. has seen the incidence of many cancers grow dramatically. For example, from 1973-1994, cases of childhood brain cancer (glioma) increased by 39.6 percent, testicular cancer increased by 68 percent and acute lymphoblastic leukemia increased 27 percent. Cancer is now the fourth leading cause of death for American children.

In 1962, Rachel Carson brought the downside of rampant pesticide use to the attention of the world. In her book The Silent Spring, she pointed out the devastating bio-accumulative effects of DDT and other such chemicals persisting in the environment. Since her time, the public has become increasingly aware of possible adverse consequences of pesticides, and almost daily evidence builds towards a relationship between pesticide application and threats to human health.

In May 1994, the Environmental Working Group (EWG) released a report called "Washed, Peeled, Contaminated" that analyzed data from the Pesticide Data Program of the United States Department of Agriculture (USDA) regarding the presence of pesticides in fresh fruits and vegetables. The report asserts that millions of adults, infants and children in the United States are exposed daily to combinations of pesticides in their food that may present long term health risks. The findings include:

&bul; More than 80 percent of peach, apple and celery samples contained residues of one or more pesticides. Apples had up to eight residues in a single sample.

&bul; Twelve different carcinogens, 17 different neurotoxins and 11 different pesticides that disrupt the endocrine or reproductive system were found in just 12 fruits and vegetables tested.

&bul; Simultaneous exposures to multiple pesticides are common even when fruits and vegetables are washed and normally prepared.

Yet, according to California Department of Pesticide Regulation reports, in 1995 in California, 188 million pounds of pesticides were applied to agriculture. That same year, Monterey County ranked fourth in overall pesticide application with almost 13 million pounds of active ingredient reportedly used, and seventh statewide in pesticide application rates with 39.6 pounds of active ingredient applied per harvested acre. Each year the pesticide industry continues to grow, burgeoning in 1996 into a $30 billion industry worldwide.

The EPA, FDA and USDA strongly refute allegations that dangerous levels of pesticides are present on food being consumed in the U.S. All three agencies maintain that while pesticide residues are routinely detected, they are nearly always found at levels way below those deemed safe by the EPA. To prove this point, the FDA conducts an annual "Total Diet Study" for which they purchase food from around the nation, prepare it according to home recipes and then analyze it for pesticide residues. According to FDA reports, the Total Diet Study "has consistently shown that the actual dietary intake of pesticide residues by Americans is less than one percent of the levels deemed safe by the World Health Organization."

The debate rages on and, based on how difficult it is to reach scientific consensus on the dangers of one type of toxin in the environment when we are exposed daily to thousands of chemicals, consumers may never know exactly how their lives are affected by pesticides.

"Whether pesticide residues found during routine sampling of fresh produce is of concern or not is a personal choice," says Diane Bowen, executive director of California Certified Organic Farmers (CCOF), a Santa Cruz-based organic produce certification agency. "We live in a contaminated world, but we can choose to eat less contaminated food. Organic is a wise choice."

For consumers who want to eat fewer pesticides, buying organic is also the obvious choice. Residue testing of organic food has detected far less pesticides than on conventionally grown produce. But because only 2 percent of all produce is grown organically, organic foods are often more costly and hard to find.

If shopping organic is not an option, here are a few other suggestions to help limit exposure to pesticides.

"Become educated about where your food is coming from and buy locally," says Bill Walker of the EWG. "Most U.S. food travels hundreds of miles and has to packaged and processed accordingly." Produce traveling long distances is more likely to be sprayed with pesticides after harvest and waxes containing fungicides are more likely to have been applied to fruits such as apples to preserve them over a longer period.

As a halfway point between organic and conventional farming, some grocery stores are offering certified produce that has been screened for pesticide residues. No Detected Residue (NDR) certification offers a "different strategy for producing food that takes away some of the risk," says Jim Knutson, chief operating officer of NutriClean, an independent certifying agency. "It gives conventional agriculture a way to answer questions about food safety and gives a low-cost or near-market alternative to people concerned about pesticide risk." Locally, Nob Hill offers seven items weekly that meet NDR standards.

Consumers who do buy conventionally grown produce should be aware that pesticides are intentionally applied so as not to wash off with water while in the field. Many pesticides contain adhesive materials like oil or wax to guarantee pesticide staying on the plants. Careful washing with a vinegar and water solution has been shown to eliminate some of the unwanted residues. Another option are products like Healthy Harvest, produce cleaners available at grocery stores developed specifically and proven to remove contamination from produce. "Healthy Harvest penetrates and breaks down the wax and anything that seals and contaminates the food," says Healthy Harvest President Dave Roach. "Even though you can''t see the pesticides, you can see the wax and see that it is gone."

By analyzing USDA data, the EWG has determined that consumers can cut their dietary risk in half by carefully consuming the 12 crops with the most toxic residues. Strawberries top the list, followed in order by bell peppers, spinach, cherries, peaches, cantaloupe (from Mexico), celery, apples, apricots, green beans, grapes (from Chile) and cucumbers. (For further information and a personal pesticide profile, visit www.foodnews.org.)

But most importantly, experts caution, don''t stop eating five servings of fruits and vegetables a day. Some foods with the lowest residues are avocados, corn, onions, sweet potatoes and bananas. By shopping wisely and cleaning carefully, it is very possible to eat a wide variety of healthy fruits and vegetables.

"Rather than eating strawberries, which are the most heavily treated with pesticides," continues Walker, "you can choose raspberries or blueberries which are significantly lower in pesticide residues. Every step we make towards reducing pesticide application and exposure is a step in the right direction." cw