Houston, Beware Bite of Mosquito Control Ruling

Zambone Op-Ed in The Houston Chronicle

In the aftermath of Tropical Storm Allison, you might be doing two things in Southeast Texas, slapping at mosquitoes and counting your blessings. If you are, add another blessing to your list: Texas isn't in the jurisdiction of the Ninth Circuit Court of Appeals. If it were, you would be slapping mosquitoes for quite a while.

In March, the Ninth Circuit in San Francisco handed down a decision that would cripple efforts to control the whining horde of mosquitoes that is currently acquiring a taste for your flesh and irritating your ears. In Headwaters Inc. vs. Talent Irrigation District, the Ninth Circuit determined that the Federal Insecticide, Fungicide and Rodenticide Act, or FIFRA, does not control the application of pesticides to bodies of water. Although FIFRA requires extensive testing of pesticides, including their environmental effects, before the Environmental Protection Agency grants approval for use, the court found that FIFRA's precautions are not enough. According to the Ninth Circuit, pesticides are pollutants under the definition of the Clean Water Act. Thus, entities wishing to apply pesticides to water must obtain a National Pollutant Discharge Elimination System, or NPDES, permit before they may do so.

While the Talent case involved herbicide applications to irrigation canals, the Ninth Circuit's decision will have a chilling effect on mosquito control. Mosquitoes breed in water, and one of the best ways to control them is to apply a larvicide, a substance that kills developing mosquitoes, to the breeding waters. Unfortunately, the Ninth Circuit's decision in Talent will categorize larvicides as pollutants. Therefore, mosquito control districts that use them will have to apply for an NPDES permit each time they need to apply larvicides. Furthermore, a large population of mosquitoes or an outbreak of a mosquito-borne disease, such as the West Nile Virus, requires the application of adulticides, pesticides that kill adult mosquitoes.

According to Talent, mosquito control districts would have to obtain a NPDES permit before they could spray adulticides near water. So what is the problem with mosquito control districts getting an NPDES permit before they spray? It is twofold. First, the permit is unnecessary. The EPA requires extensive testing before it will grant a product a FIFRA label. This testing encompasses the pesticide's effect on bodies of water. Pesticide labels use the data to give specific instructions as to when and where applicators may use these substances. Second, applying for a NPDES permit is not a simple process. It may take several weeks and requires the applicant to conduct extensive monitoring of the possibly affected waters. You don't get an NPDES permit over the phone. It takes time. Time is precisely what you don't have during an outbreak of mosquito-borne disease. These diseases appear and spread rapidly. So rapid is the onset of a mosquito-borne disease that a report from the National Academy of Sciences designated adulticides as the only effective weapon against their spread. All other methods of control take too long to curb an initial outbreak.

It may seem like an aberration now, but illness or death due to mosquito-borne diseases was common in U.S. history. Yellow fever epidemics decimated urban populations. Dengue ravaged the Gulf states. Malaria threatened most of the country until the mid-20th century. The National Academy of Sciences report drew its conclusions as to the effectiveness of adulticides from the analysis of an outbreak of St. Louis encephalitis that occurred in Dallas in 1966. The price of fewer deaths from mosquito-borne disease is vigilance. Mosquito control efforts have curbed the incidence of these diseases, by reducing the number of mosquitoes that carry them.

In order to reduce mosquito populations like the one plaguing Houston now, mosquito control districts need instant access to larvicides and adulticides, access that the Ninth Circuit's decision may irretrievably delay. Mosquitoes in Texas may not be safe now, but that might change. The Ninth is an influential circuit in federal law, and the EPA likes to have a standard federal policy. If the Ninth Circuit's decision in Talent stands, it may soon affect how many mosquitoes live in Texas, too.

Copyright © 2001 The Houston Chronicle