An understanding of the regulatory and legal standing of pesticide compounds such as molluscicides can be useful in handling these products. Howe et al. (1994) and Burns (1994) describe how FIFRA, enacted in 1972, relates to the registration and use restrictions of chemicals for zebra mussel control. The act monitors chemicals intended for control of living organisms and, as amended, requires registration and reregistration by the USEPA of pesticides sold or used in the United States to ensure that they will not cause unreasonable risk to the environment or human health when used according to the label directions. These regulations then apply to anyone who manufactures, formulates, markets, distributes, uses, or disposes of pesticide products, including aquatic biocides.
The primary registration mechanism is governed by FIFRA Section 3. Applications for registration of molluscicides may be for new active ingredients, the new use of a previously registered pesticide, or chemicals similar to currently registered compounds. The registration process (paid for by the registrant) is not inexpensive or fast because it requires detailed research by the registrant to determine the efficacy and environmental side effects of the active ingredient. Some of this testing is carried out via Experimental Use Permit (EUP) provisions under FIFRA Section 5. This may delay or prevent approval for use of the compound in a specific state. Most states require their own specific registration of pesticides in addition to registration with the USEPA. The expense of acquiring registration for biocidal compounds has understandably slowed the proposal and marketing of new chemicals specifically for the small area of zebra mussel control.
The effect of discharge of water containing molluscicidal chemicals on downstream receiving waters must be considered prior to the formulation of a treatment program. Even with discharge limits and requirements and the use of deactivation, there may be an effect on the ecosystem that needs to be avoided or restricted to certain times of the year (Claudi and Evans 1993). The legislation currently used to control direct discharges to waters of the Nation is the NPDES permit program. This was made possible by the passage of the Federal Water Pollution Control Act Amendments of 1972 (also referred to as the Clean Water Act). These permits place limits on the amount of pollutants that may be discharged to waters by each discharger. These limits are set at levels protective of both the aquatic life in the waters that receive the discharge and human health. The Clean Water Act requires that registered biocides discharged to waters of the United States from a point source must be regulated such that WQBELs for that biocide are established in an NPDES permit to meet State water quality standards. There must also be compliance with each State's Antidegradation Policy. Thus, one of the label requirements for use of many aquatic biocides and pesticides in aquatic environments is to obtain an NPDES permit from the appropriate State/Tribal agency or USEPA Regional Office and to comply with State water quality requirements. Lack of a permit could result in enforcement action under FIFRA and the Clean Water Act. A risk-benefit analysis is also carried out by the USEPA, and a pesticide can be designated for Arestricted use if it is judged as presenting a high risk to humans or the environment. States usually require these chemicals to be applied only by certified applicators or people in their employ.
As well as FIFRA Section 3 registration, conditional use of pesticides may be authorized through Special Local Needs under Section 24(c); through Emergency Exemptions (ee) (Section 18); or through EUP provisions under Section 5. Use of a registered product on a pest not listed on the product label is allowed under Section 2(ee) as long as application is to a site stated on the label (Howe et al. 1994). However, specific registration for use in once-through cooling systems is required in many water handling operations where mussels are treated in these areas (Claudi and Mackie 1994).
It is important to remember that the product label of a registered pesticide is a legal document. Use of an aquatic biocide or molluscicide in a way that is inconsistent with the instructions provided on the label is a violation of FIFRA and can result in civil or even criminal action, via proceedings from the USEPA under FIFRA or from certain states (Howe et al. 1994). Compliance with the National Environmental Policy Act (NEPA) is required if Federal funds are used for zebra mussel control. This legislation dictates that control methods used at public facilities must not negatively affect native biota or existing water quality (Miller et al. 1992). A protocol for compliance with the NEPA process that should used in developing chemical control strategies for zebra mussel is described by Miller et al. (1992), and a working plan is reported on by Tippit, Cathey, and Swor (1993).