Mosquito-misting systems are outdoor, time-release systems utilizing a series of plastic tubing lines and spray nozzles to distribute insecticide throughout an individual backyard, primarily for mosquito control. These systems are increasing in popularity among homeowners, but there remains concerns by EPA and state regulators regarding the certification of equipment installers, pesticide product labeling for such applications, homeowner liability, consumer access to the insecticide label information, security of on-site chemical containers, insect resistance, advertising claims, acute and chronic health effects, efficacy of the products to control the target pests, nontarget damage, drift to nearby residents, right-to-know outdoor posting of applications in applicable states, and the systems' conflict with Integrated Pest Management principles.

Following is much of the content of a draft "Issue Paper" prepared by the State FIFRA Issues Research and Evaluation Group (SFIREG), to be delivered to EPA. FIFRA refers to the Federal Insecticide Fungicide and Rodenticide Act, the main federal law that regulates pesticide use in the United States. SFIREG consists of representatives of the lead pesticide regulatory agencies of each U.S. state, territory, and Indian tribal organization that work with EPA to ensure a proper working relationship concerning pesticide laws and regulations. In Illinois, the Illinois Department of Agriculture, Illinois Department of Public Health, and University of Illinois Pesticide Safety Education Program have representatives in meetings between SFIREG and EPA.

Due to the growing national public concern over West Nile virus, automated misting systems are being marketed and installed as a method for homeowners to control mosquitoes in and around their homes and property in residential areas. This is extremely troublesome due to a huge potential for exposure to people, pets, wildlife, and the environment from unnecessary and arbitrary pesticide applications.

Problems attributed to the use of these systems in residential areas include

1. The systems are often marketed and installed by companies whose employees have no experience or knowledge of pesticides or proper application. Many are not required to obtain commercial pesticide licensing because they only install the equipment and do not "apply" the pesticide, therefore states may have limited abilities to regulate these individuals.
   
2. A number of companies currently utilize the Internet to advertise the service. Photos supplied on these sites show the systems spraying in areas around the home, such as under the eaves or around pools and play structures. Often installation includes areas around the property perimeter without regard for possible consequences on neighboring property. Improper public health protection claims are being made on these sites as well.
   
3. Units are set to automatically mist at timed intervals, causing unnecessary applications to be made that will have no effect on the pest or may cause development of insecticide resistance in the pest population. Different mosquito species fly and search for blood meals at particular times of the 24-hour day. Many mosquito species do not feed on humans or their pets or do not carry diseases to humans or pets. Some mosquitoes feed as larvae on other mosquito larvae, providing biological control of potentially harmful species. Mosquitoes are an important source of food in many eco-systems. Indiscriminate elimination of mosquitoes can impact the ecology and limit the number of songbirds and other wildlife that people enjoy.
   
4. Off-target spray drift is a potential in windy and/or rainy conditions.
   
5. Remote-control units are also available, allowing the application to be "controlled" by children or teens "playing" with the system, causing potential harm to unsuspecting friends or pets.
   
6. The claims by companies installing these systems equate to claims made for the product itself as "safe" and "nontoxic," which is not allowed by EPA to be on labeling.
   
7. Installation of these systems around property that borders areas inhabited by wildlife may draw animals as a watering source if nozzles drip. Birds may perch on installed lines and also use nozzles as a water source. This can result in the poisoning of songbirds and other desirable wildlife.
   
8. The pesticides are sold or provided to the homeowners to "maintain" the system, often without any warning about the need for proper mixing, use, and disposal, or about the potential for harm. This use allows an unmonitored, unnecessary, and often ineffective pesticide application as a means of mosquito control. Recent studies have shown a lack of adequate reading and understanding of pesticide labels by homeowners.
   
9. State vector control departments and Mosquito Abatement Districts are attempting to provide mosquito control through homeowner education and use of IPM techniques such as the elimination of breeding sites, use of larvicides to maintain beneficial insect populations, and other cultural control methods. Use of these systems may discourage homeowners from assisting in effectively addressing and preventing mosquito problems by allowing only a "perceive" or "band-aid" effect through use of these systems. A resistance problem caused by continual applications of the pyrethrum or pyrethroid class of insecticides through automated systems will result in a control failure or use of pesticides with active ingredients with higher concentrations and toxicities.

In Illinois, staff at both the University of Illinois and state agencies feel that the use of mosquito-misting systems should be restricted, if they are used at all, primarily for the reasons listed above. Before purchasing, selling, or maintaining any of these systems, realize there are preferable methods of controlling disease-carrying mosquitoes and that these systems may be endangering human and ecosystem health through their somewhat indiscriminate use of insecticide. For additional information on these systems and the controversy surrounding them, refer to the National Pest Management Association Web site on these devices at http://www.npmapestworld.org/mms/.

(Phil Nixon)