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Texas Environmental Almanac, Environmental Focus: Pesticides, Page 2

RISK ASSESSMENT: A TRICKY BUSINESS

As pointed out, before any pesticide is used on a food crop, the EPA must set the residue tolerance levels. In determining the allowable minimum residue, EPA uses an approach called risk assessment. Risk assessment is the basis for most food-safety
and toxic-chemical regulatory decisions made in the United States and other countries.(26)

Risk assessment is, as one author states, "the process of determining the probability of a bad outcome."(27) In other words, to what quantity of a particular pesticide can humans be exposed without experiencing unacceptable harm? In assessing the potential dangers of pesticides to humans, the EPA considers cancer, not reproductive damage, neurological damage, respiratory or immune system damage. Although the EPA historically has not followed any strict risk analysis guidelines, it now considers a risk of one additional case of cancer per one million population as an insignificant, or negligible, risk.

In setting pesticide tolerance levels for food crops, the EPA has relied on risk assessment studies conducted on animals and provided by the manufacturer. In these studies experimental animals are exposed to various doses of a single pesticide. The EPA extrapolates from the resulting data the possible harm a single pesticide ingredient might pose to an average healthy adult. Sometimes these risk assessments are done for animals to determine, for example, how many pounds of pesticides in a lake will certain fish be able to tolerate.

Critics believe that EPA's risk assessment tool for the setting of pesticide tolerance levels in food crops raises a number of important issues, including:(28)

• EPA does not consider that children eat more fruit in relation to their body size than adults or that they are developmentally more vulnerable to toxins and carcinogens than adults.(29)

• In setting tolerance levels, the EPA does not consider that raw fruits and vegetables may carry more than one kind of pesticide and that these combined residues might have an adverse synergistic effect.

• The EPA does not take into consideration that people are exposed to pesticides by other routes. Therefore, there is no examination of the possible synergistic effects.

• In conducting risk assessments, agencies do not apply uniform guidelines, therefore risk assessments for the same chemical may vary from agency to agency.

• The necessary data on the health effects of chemicals do not exist and because of cost might never exist.

Despite these suggested limitations, risk assessment studies are widely used and accepted in the scientific community. Many scientists in industry and the regulatory agencies believe that the generally conservative assumptions used in many risk assessments can compensate for unknowns like synergistic effects or lack of full health studies.

A recent court decision has challenged the EPA's approach, finding that pesticides in food crops should be treated as additives to food, with a zero tolerance for carcinogens.

THE DELANEY CLAUSE: AN ALTERNATIVE TO RISK ASSESSMENT

The alternative to traditional risk-assessment techniques in setting pesticide tolerance levels in food crops is found in federal regulations on food additives. In 1958, Congress added the so-called Delaney Clause to the Food and Drug and Cosmetic Act. This amendment provides that no chemical which causes cancer can be added to processed food regardless of the level of concentration or the level of risk. In effect, Congress determined that the uncertainties surrounding any attempt to assess the risks of cancer were too great. As a way to assure protection and avoid costly government evaluation, the simple ban was imposed. The EPA, under President Clinton, has proposed to substitute this "zero-risk standard" for processed foods with the "negligible risk" standard being applied to raw foods. In other words, using the "negligible risk" standard, processed foods could have "approved" cancer-causing chemicals.

In determining health and environmental effects, the EPA considers only the active ingredients in pesticides, not the "inert" ingredients - those used to dilute or carry the active ingredient. A study by the EPA of 1,200 inert ingredients found 55 of known toxicity, 51 with a molecular structure similar to those of known toxicity, 900 of unknown toxicity and 200 generally recognized as safe.

Source: League of Women Voters Education Fund, America's Growing Dilemma: Pesticides in Food and Water (Washington, DC: League of Women Voters Education Fund, 1989), 7.

PESTICIDE USE AND REGULATION IN TEXAS

With 32 million acres of cropland, Texas ranks near the top of all states in the volume of pesticides applied in agriculture in 1991.(30) The exact amount of pesticides used in Texas for non-agricultural purposes, including use in homes and gardens, schools and other buildings and commercial structures, has not been compiled by any government agency.

In Texas, eight state agencies or boards operate some type of pesticide program.(31) The major Texas agencies and boards with pesticide-related responsibility are:

• The Agriculture Resources Protection Authority, created by the Texas Legislature in 1989 to coordinate policies and programs of all Texas agencies related to the control of pesticides in Texas. The Agriculture Resources Protection Authority is mandated by state law to meet quarterly; however, from October 1992 until August 1994, the Authority did not meet.

• The Texas Department of Agriculture has primary responsibility for pesticide registration and enforcement. It is also responsible for an organic food and fiber certification program and for aspects of the Integrated Pest Management program.

• The Structural Pest Control Board has responsibility to license applicators of pesticides used in and around homes and other buildings.

• The Texas Natural Resource Conservation Commission regulates storage and disposal of pesticide waste and containers. The Texas Natural Resource Conservation Commission also has authority for monitoring pesticides in groundwater.

• The Texas Department of Health regulates the use of pesticides for health purposes, including for the control of mosquitoes. The Texas Department of Health regulates the use of pesticides in restaurants and conducts special studies on the potential health impacts of environmental contaminants, such as pesticides. Doctors are required to report pesticide-related illnesses to the Texas Department of Health.

• Texas A&M University's Agricultural Experiment Station is involved with research efforts on major obstacles facing agricultural production, including the use of pesticides and alternatives to pesticides.

• Texas A&M University's Agricultural Extension Service provides scientific information and research findings developed by the experiment
  station to farmers, ranchers and the public.

• The Texas Soil and Water Conservation Board is the lead agency for agricultural non-point-source pollution, including pesticide pollution.

STATE PESTICIDE REGULATIONS

The Texas Department of Agriculture, like many state agencies charged with pesticide regulation, acts as a "gatekeeper" for the federal law. Though each state can impose certain stricter standards and ban federally approved pesticides or restrict their use, few states take these actions. The Texas Department of Agriculture has not banned any pesticide that has been federally registered.(32) It did restrict the use of chlordane in 1989 before a federal ban was put into effect. Texas has also restricted the use of some pesticides - mainly herbicides - that are not federally restricted.

Texas Environmental Almanac, Environmental Focus: Pesticides, Page 2

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