Calculating Dietary Exposures of Children

To estimate potential exposure to pesticide residues, EPA uses food consumption data gathered as part of the U.S. Department of Agriculture's Nationwide Food Consumption Survey. The survey profiles the types and amounts of food consumed over several days for all Americans, as well as subgroups.

All foods are analyzed by their separate ingredients using EPA standard "recipe files" for 300 different foods. For example, the amount of wheat flour, tomato, cheese, oregano, and other ingredients are estimated for a serving of pizza. All foods in a person's daily diet are analyzed, and the amounts of similar food components are added (e.g., total amount of wheat flour consumed from various foods in a day). These data, in turn, are used along with information on pesticide residues on individual foods to estimate overall dietary exposure to a pesticide.

EPA also has developed a special data base known as the Dietary Risk Evaluation System (DRES). This system allows the agency to refine its exposure estimates for pesticides in the diets of infants, children and other potentially sensitive subgroups. The DRES system provides information on food consumption for more than 300 food commodities for 22 different subpopulations.

According to William Farland, Ph.D., director of EPA's Office of Health and Environment Assessment, "If the DRES analysis indicates that exposure to a subgroup is so high that adverse effects may occur, then EPA will not approve a tolerance even if the estimated risks to the overall population are acceptable."

One case in which EPA did not approve a tolerance because of specific dietary concerns for infants and children involved the pesticide pydrin in 1985. New uses of the chemical on alfalfa and sorghum were requested to be allowed. However, EPA determined that the potential risks to children from secondary residues in milk from cows eating such grains were unacceptable, and the agency denied the request.

When it comes to food additives, FDA requires the manufacturer or sponsor of a food additive petition to provide an estimate of the anticipated consumption of the substance, based on the food categories in which its use is proposed. Such data include frequency of consumption and amounts consumed by all age groups, based on a nationally representative sample of Americans.

Food Protection for Children

Children Are Not Small Adults

Children cannot be viewed simply as miniature adults, said pediatricians, toxicologists, and regulators gathered last fall at a risk assessment symposium on similarities and differences between children and adults. Sponsored by the Environmental Protection Agency and the International Life Sciences Institute, the symposium evaluated biological, social and environmental factors related to children that can affect their risk from foods, pesticide residues or other substances.

Most notably, children's dietary patterns differ from adults in both quantity and types of foods consumed. In relation to body weight, children eat more food than adults to meet their demands for rapid growth. This is particularly true among preschoolers.

Also, children's consumption of certain types of foods such as fruits and fruit juices can be quite different from adults. In addition to these basic dietary differences, variables such as nutritional status, socioeconomic level, culture and geographic location can profoundly affect a child's health risk from certain substances.

While not exposed to the same occupational hazards as adults, children's home, school and play surroundings can influence their health risk. J. Michael Davis, Ph.D., a health scientist with the EPA Office of Health and Environmental Assessment, has noted that children are generally exposed to much higher levels of lead through airborne sources, household dust and soil, lead paint, and pipes, in addition to diet. Thumbsucking and other typical hand-to-mouth behaviors may account for as much as 80 percent of all children's lead-related exposures.

Several biological factors in children can make them either more or less sensitive than adults to various substances. Children have higher rates of breathing and blood flow, and many of their organ cells multiply at a faster rate through normal growth. Also, the rate at which certain drugs or chemicals pass through cell membranes in children varies from adults, influencing potential toxicity.

In addition, children's metabolism of certain chemicals may be more or less efficient than adults. Young children are known to have a greater tolerance than adults to acetaminophen, the most widely used over-the- counter drug for pain and fever in the United States. Some scientists believe this phenomenon may be due to children's greater capacity to safely eliminate the drug by non-toxic metabolic pathways.

The immature immune systems of infants and children can also place them at greater risk from infection, including microbiological contamination of foods. Health officials are stepping up public education efforts to reduce incidence of foodborne illness in children and other groups such as the elderly that may have vulnerable immune systems.

Children and Food Safety Risk

Whether selecting a family car, deciding where to live or just choosing what to watch on TV, parents everywhere tend to share the same credo- nothing's too good for my kids.

Ensuring the safety and wholesomeness of foods for infants and children is no exception.

But public confidence in food safety for the nation's 63 million youngsters is unsteady. As one recent example, the Alar controversy panicked many parents into pouring out apple juice and school officials into banning the sale of apples from school-lunch programs.

And according to a recent poll by the Center for Produce Quality, 72 percent of Americans believe pesticide regulations do not sufficiently account for children's health risks.

In the wake of such concerns, child health advocates, environmentalists, the food industry and others are working with federal authorities to bring the best scientific evaluation possible to pesticides and other food-related risks to children.