Medfly Eradication and Public Health: A Fruitless Effort?

California Department of Health Services. “Health Risk Assessment of Aerial Application of Malathion-Bait.” California Department of Health Services (February 1991).

Segawa R.T. Calif. Dept. of Food and Agriculture. Environmental Monitoring and Pest Management, “Environmental Monitoring of Malathion Aerial Applications Used to Eradicate Mediterranean Fruit Flies in Southern California, 1990.” EH 91–3, (3/91), p. 4.

California Department of Health Services. Answers to Health Questions about Aerial Application of Malathion (July, 1993).

Hawkins Larry . “Medfly Cooperative Project.” Personal communication, cited in Action Now, Comments on Draft Programmatic Impact Report: The Exotic Fruit Fly Eradication Program Using Aerial Application of Malathion and Bait (June 1993), p. 9.

Otten Noel , Action Now. Personal Communication (October 27, 1993).

Dolan Maura and Dunn Ashley . “Growers Express Fears and Anxiety Over Medfly War,” Los Angeles Times, (January 12, 1990), p. B-8.

In Florida, for instance, the Caribbean Fruit Fly (Caribfly) has been the object of eradication efforts. As used in this paper, the terms medfly and eradication include these related species.

The assumption that the medfly can be eradicated is contrary to respected scientific opinion which suggests that the medfly is already established, its appearance in the US being the natural extension of its long-term cyclical range fluctuation, and that attempts to eliminate it are bound to fail. See Carey 1991; for a more popular account, see Wheeler 1993.

The final EIS was issued while this paper was in preparation; publication deadlines have precluded detailed examination of the final text which, while substantially similar to (and for the most part a verbatim reproduction of) the draft issued in April 1993, may contain changes which are not reflected in the present commentary.

Given the repetitive and fairly predictable nature of medfly episodes, both words in the agency's preferred alternative, “emergency eradication,” are questionable as descriptors. As used by APHIS, the term “eradication” is easily confused with the commonsense meaning of the word (for example, as in the worldwide eradication of smallpox), but is used to mean simply a continuation and expansion of the existing chemical suppression program. Presumably, since the cooperative programs are funded to some extent with state emergency funds, the programs should address legitimate emergencies.

As it goes through its 30- to 60-day life span of egg-laying and fruit-devouring, the medfly can pose substantial problems for agriculture. By laying its fertilized eggs just under the surfaces of fruits and vegetables (medfly affects over 250 varieties), the female medfly scars the host fruit superficially. Within 12 days, the eggs hatch into larvae, which then feed upon the fleshy interior of the host, leaving the produce insect-contaminated and rotted. The life-cycle changes continue after about seven to 10 days, when the mature larvae leave the fruit, often going into the soil as the fruit drops prematurely. In the soil, the larvae develop into pupae and, within eight to 14 days, adult medflies emerge to begin the reproductive cycle once again.

Section 18 — USDA Quarantine Exemptions for Use of Malathion and Diazinonto Eradicate Exotic Fruit Fly Species in Florida — ACTION MEMORANDUM. Memorandum from Anne E. Lindsay, Director, Registration Programs, to Douglas D. Campt, Director, EPA Office of Pesticide Programs, 1991.

Section 18 — Quarantine Exemption for the Use of Malathion to Eradicate Exotic Fruit Flies in California (EE #93-CA-02) — Action Memorandum from Lawrence E. Culleen, Acting Director, Registration Division, to Douglas E. Campt, Director, EPA Office of Pesticide Programs, dated 14 December 1992.

Decades-long attempts by APHIS' sister agency to eradicate western spruce bud worm similarly were characterized by repeated aerial spraying of thousands of square miles (with DDT, carbaryl, and other pesticides), with claims of success after each project, and treatment protocols that included no methodology for measuring long-term success. As with the medfly programs, the term eradication in practice meant perpetual suppression. Protests by citizens and then lawsuits eventually led the Forest Service to drop eradication goals and adopt instead successful non-chemical management methods, including setting of realistic acceptable-damage thresholds and benchmarks for determining success or failure of the management programs. (See Integrated Pest Management Working Group, The Path from Here: Integrated Forest Protection for the Future, ed. Brown Dave . Albuquerque, N.M.: USDA-Forest Service, Region 3, 1986.)

During recent spray programs in the Los Angeles area, citizens' groups, many of which were formed in direct response to the spraying of their neighborhoods, organized numerous demonstrations, set up citizen information hotlines and attended California Department, of Health Services meetings in force. Since 1990, members of many of these groups have been active under the umbrella of Action Now, which has taken a leading role in calling for alternatives to chemical eradication. Among national organizations opposing the APHIS proposal are the National Coalition Against the Misuse of Pesticides and the Sierra Club.

Brenner Loretta , “Malathion.” Journal of Pesticide Reform, 1992, 12(4): 29.

Rodgers Kathleen , “Mechanisms of the Modulation of Purine Peritoneal Cell Function and Mast Cell Degranulation by Low Doses of Malathion.” Agent Action, 1992, 35: 57–63.

Brown Mark A. , “Monitoring of Malathion and Its Impurities and Environmental Transformation Products on Surfaces and in Air Following an Aerial Application.” Environmental Science and Technology, 1993, 27(2): 388–397.

“Malathion Public Health Effects Advisory Committee Final Report: Charges and Recommendations.” California Office of Environmental Health Hazard Assessment, Pesticide, and Environmental Toxicology Section (February 1992).

Human Health Risk Assessment: APHIS Fruit Fly Programs. Syracuse Environmental Research Associates (November 1992).

Non-target Risk Assessment for the MEDFLY Cooperative Eradication Program. Syracuse Environmental Research Associates (February 1993).

Sierra Club and Arizona Toxics Information, Comments on the USDA-APHIS Medfly Cooperative Eradication Program Draft Environmental Impact Statement —1993. Bisbee, Arizona, June 18, 1993.

Action Now. Comments on Draft Programmatic Environmental Impact Report: The Exotic Fruit Fly Eradication Program Using Aerial Application of Malathion and Bait (June 1993).

Arizona Center for Law in the Public Interest. Medfly Eradication Program — Draft EIS (May 21, 1993).

National Research Council. Environmental Epidemiology, Vol. 1: Public Health and Hazardous Wastes. Washington, D.C.: National Academy of Science, 1993.

Birnbaum Linda S. , “Advances in Estimating and Predicting Health Effects from Exposure to Environmental Toxicants.” Paper presented to the USPHS-ATSDR International Congress on the Health Effects of Hazardous Waste, May 3–6, 1993, Atlanta, Georgia.

Davis Devra , “Overview of Environmental Epidemiology: Establishing Causal Links between Exposure to Hazardous Waste and Human Disease.” Paper presented to the USPHS-ATSDR International Congress on the Health Effects of Hazardous Waste, May 3–6, 1993, Atlanta, Georgia.

Lucier George W. , “Molecular-Epidemiologic Approaches to Assessing Public Health Impacts of Hazardous Waste.” Paper presented to the USPHS-ATSDR International Congress on the Health Effects of Hazardous Waste, May 3–6, 1993, Atlanta, Georgia.

Lioy Paul J. , “Frontiers of Exposure Assessment for Hazardous Waste Sites.” Paper presented to the USPHS-ATSDR International Congress on the Health Effects of Hazardous Waste, May 3–6, 1993, Atlanta, Georgia.

Waldman Jed , “A Framework for Exposure-Dose Modeling and Data Needs for Hazardous Waste Sites.” Paper presented to the NIEHS Joint United States-Mexico Conference on Fate, Transport, and Interactions of Metals, April 13–16, 1993, Tucson, Arizona.

Wegman Patricia Ostrosky , “Human Biomarkers in Exposed Populations.” Paper presented to the NIEHS Joint United States-Mexico Conference on Fate, Transport and Interactions of Metals, April 13–16, 1993, Tucson, Arizona.

Cohen Steven D. “Mechanisms of Toxicological Interactions Involving Organophosphate Insecticides.” Fundamentals of Applied Toxicology, 1984, 4: 315–324.

Richter E.D. , “Illness and Excretion of Organophosphate Metabolites Four Months after Household Pest Extermination.” Archives of Environmental Health (March/April 1992 [Vol. 47, No.2]).

Wallace Lance A. The Total Exposure Assessment Methodology (TEAM) Study: Summary and Analysis: Volume I. EPA/600/6-87/002A (June 1987).

“The Use and Environmental Impact of Organophosphorus Compounds in the Mediterranean Region.” Submitted by Greenpeace International to the Joint Meeting of the Scientific and Technical Committee and the Socio-Economic Committee of the Mediterranean Action Plan. Athens, 6–10 May 1991.

Dobroski Charles J. “Malathion: A Profile of Its Behavior in the Environment,” 1987, Submitted to USDA-APHIS-PPQ under Contract No. 53-6395-1-1151.

Cohen Steven D. “Mechanisms of Toxicological Interactions Involving Organophosphate Insecticides.” Fundamentals of Applied Toxicology, 1984, 4: 315–324.

Reuber Melvin D. 1985. “Carcinogenicity and Toxicity of Malathion and Malaoxon.” Environmental Research 37: 119–153.

World Health Organization, International Agency for Research on Cancer, IARC Monographs on the Carcinogenic Risk of Chemicals in Humans — Miscellaneous Pesticides (vol. 30), 1983.

U.S. Army 1976. Study #51-051-73/76.

Bushnell M. Journal of Pharmacology and Experimental Therapeutics; cited in, Adler Tina 1992, “Pesticides Long-term Effects Get a Closer Look from EPA,” American Psychological Society Newsletter (December, 1992), p. 44.

Sadun Alfredo M.D. Letter to Brian Dementi, USERA, Wash. DC, 1 Aug. 1990.

Wagner Sheldon , Letter to Frank Davido, OPP Pesticide Incident Response Officer (24 August 1990).

The HED memo, one of a series of EPA memos reviewing the CDHS assessment document, includes several specific critical comments on the toxicology and exposure components of CDHS' conclusions, noting (among other points) that 1. “there were no actual human monitoring data with respect to post-application exposure;” 2. “under certain high-exposure scenarios, there was little or no margin of exposure (margin of safety, as used in the document) for skin irritation and 20 percent inhibition of acetylcholinesterase activity;” 3. “although these [model-derived exposure] estimates may provide a fair characterization of the risk because of conservative exposure estimates, this characterization still abounds with uncertainties;” 4. “additional chronic studies on these compounds [malathion and malaoxon] are needed to research the endocrine pathology and the mechanisms of the genotoxicity;” 5. “CDHS requires at least two positive studies before a chemical is considered carcinogenic [whereas EPA] may determine that a chemical has carcinogenic properties based on one positive study,” and although “because of the lack of adequate evidence of carcinogenicity CDHS does not classify malathion or malaoxon as a carcinogen,” EPA's “HED continues to have a concern for the carcinogenic potential” of the chemicals; 6. “HED has concerns for the potential damage to the eye from exposure to malathion;” 7. “To reduce the number of assumptions required for a risk assessment of the aerial application of the malathion-bait … at a minimum, data from an acute-testing battery should be available for a health assessment;” 8. also, “to reduce the number of assumptions for a risk assessment, additional exposure data would be useful;” and 9. “HED's most current DRES analysis based on anticipated residue and crop treatment data shows that exposure from consumption of treated crops is estimated to be approximately 120 percent of the RfD. For non-nursing infants and children up through age 12, the dietary exposure ranges between 175 percent and 250 percent of the RfD” (Reference 57, 1–3).

Review of the Health Risk Assessment of Aerial Application of Malathion-Bait submitted by California Department of Health Services. Memorandum from Penelope A. Fenner-Crisp, Director, Health Effects Division, to Anne E. Lindsay, Director, Registration Division, dated 24 April 1991.

EPA Occupational and Residential Exposure Branch Response to Questions from OMB Regarding the Malathion Data Call-in (DCI). Memorandum from Jeff Evans, Re-registration Section, to L. Rossi, Branch Chief, Re-registration Branch, Special Review and Re-registration Division, 1992.

Human Health Risk Assessment: APHIS Fruit Fly Programs. Syracuse Environmental Research Associates (November 1992).

“Exposure Estimation” in: California Department of Health Services' “Health Risk Assessment of Aerial Application of Malathion-Bait.” Memorandum from Mark I. Dow, Special Review and Registration Section, EPA Occupational and Residential Exposure Branch, to Penelope Fenner-Crisp, Director, Health Effects Division, dated 18 April 1991.

Post-project studies carried out by the California Department of Food and Agriculture are referenced in the DEIS (p. 79) only in regard to malaoxon concentrations in swimming pools.

National Research Council. Pesticides in the Diets of Infants and Children. Washington, D.C.: National Academy of Sciences, 1993.

Besides its plant and animal quarantine programs, APHIS is also responsible for broadscale chemical programs against Bollworm and Boll Weevil, Rangeland Grasshoppers and Mormon Crickets, Gypsy Moth and other invertebrates, as well as the controversial Animal Damage Control program that targets such birds and mammals as blackbirds, ravens, coyotes, bears, wildcats, mountain lions, and other predators.

Revere CT . and Rigg Melissa , “Spray Enters Coolers at Homer Davis Elementary.” Arizona Daily Star (25 April 1987), p. B-l.

“Indigenous Cooperative Blocks Malathion Spray Program.” Pesticide Action Network North American Regional Center Global Pesticide Campaigner, 1992, 2(4): 13.

Anon ., “Biological Control of the Mediterranean Fruit Fly.” Journal of Pesticide Reform, 1993, 13(1): 30.

Shuchman Lisa , “Florida Fights Fruit Flies with Wasps.” San Francisco Chronicle (July 14, 1993).

Tumlinson James , “How Parasitic Wasps Find Their Hosts.” Scientific American (March 1993) p. 100–106.

Associated Press, “Worm Seen as Weapon Against Fruit Fly.” New York Times (December 27, 1991), p. A13.

International Advisory Panel, “Review of the Program: Eradication of the Mediterranean Fruit Fly from the Los Angeles Basin,” (Oct. 4–8, 1993).

USDA and CDFA, “Eradication of Medfly from California: 1995–1995 Workplan,” (January 3, 1995).

USDA, “Q&A on L.A. Basin Sterile Release Plan.” (January 13, 1995).

California Department of Food and Agriculture, “Mediterranean Fruit Fly Eradication Project: Project Status,” (March2. 1995).

California Action Network . Into the Sunlight: Exposing Methyl Bromide's Threat to the Ozone Layer (November, 1992).

O'Brien Mary . “Methyl Bromide: Time to Stop the Killing. Global Pesticide Campaigner, 1992, 2(3): 1, 4–5, 12.

EPA-OAP. 58 Federal Register, at 15014 (18 March 1993).

Silva J. , “Tougher Peel Repels Fruit Flies.” Agricultural Research, 1993, 41(2): 14–18.

Stix Gary , “Village Pharmacy: The Neem Tree Yields Products from Pesticides to Soap.” Scientific American (May 1992) p. 132.