PANNA: Pesticide Drift Poisons in Central Valley


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Pesticide Drift Poisons in Central Valley
May 14, 2004

Last week, in two separate incidents, drifting pesticides poisoned bystanders in California’s the Central Valley. Both incidents occurred during the springtime heavy spraying season, and underscore the dangers of pesticide drift for workers and surrounding communities.

On Tuesday, April 27, 2004, 44 children riding home on a school bus near Fresno turned a corner and ran into a cloud of pesticides drifting from a nearby grape field. A number of children and the driver experienced throat and skin irritation. Eleven of the children were treated in area hospitals.

Fresno County Agricultural Commissioner Jerry Prieto Jr. said of the chemicals used on grapes in the area for mites, fungus, and mildew, “though they can cause eye irritation and can irritate mucus membranes, they have no toxicity to humans.” Medical professionals, however, consider eye irritation and irritation of mucus membranes clear indicators of at least mild poisoning by many kinds of pesticides. The chemicals involved in the poisoning were later identified as gibberellic acid, a growth enhancer, and liquid sulfur.

An official with the Kings Canyon Unified School District said the incident was “scary” for the children on the bus. The school district, which serves a number of agricultural towns, has a message to growers on their website; “Please be alert for our ever moving, large, school bus fleet and children who may be waiting at school bus stops as you prepare your orchards and vineyards for agricultural spraying of pesticides and fertilizers.”

Days later, on Sunday May 2, nineteen farmworkers harvesting peaches near Arvin became ill when a wind-shift caused pesticides to drift from a potato field about half a mile away. Emergency personal reported that when they arrived several workers were unconscious or semi-conscious, and other affected workers were being brought in by co-workers. Thirteen workers were transported to hospitals. United Farmworkers (UFW) reported that three workers remained hospitalized for several days. In the following days, seventy or more workers eventually sought medical evaluation as a result of their pesticide exposure. An investigation by the Kern County Agricultural Commissioner is still underway.

The potato field had been sprayed by helicopter with Monitor 4, a pesticide product containing methamidophos, a highly acutely toxic neurotoxin in the organophosphate class. The spray mix also contained Penncozeb 75 DM, the active ingredient of which is mancozeb, a developmental and reproductive toxicant, endocrine disruptor, and probable carcinogen that is listed as Hazardous Air Pollutant by the U.S. EPA. As a reproductive toxicant, mancozeb is particularly dangerous to the developing fetus. UFW has advised that one and possibly two pregnant women are among those affected.

Fields of Poison, a report by PANNA and Californians for Pesticide Reform (CPR) on pesticide related illness lists mancozeb as one of the top 20 chemicals causing farmworker poisonings. One of the hospitalized workers reported continued exhaustion, weakness and depression when interviewed by Teresa DeAnda of CPR days after her release. Still traumatized, the farmworker described symptoms of intense nausea and headache, and losing consciousness while lying in the dirt next to the field. She has no memory of her decontamination, in which firefighters cut away her clothing and sprayed her with a fire hose.

Arvin was also the site of a poisoning incident in July of 2002, when 250 people were sickened by pesticide drift. In January 2004 Western Farm Service, one of the largest pesticide applicator companies in the western U.S. agreed to pay fines of $50,000 to the California Department of Pesticide Regulation and $10,000 to the Kern County Agricultural Commissioner for the incident. It is important to note that fines do not include reimbursement for medical expenses incurred as a result of the exposure. In the recent Arvin incident, a number of affected workers refused medical treatment, citing concerns over payment of the costs.

CPR and California Legal Assistance Foundation (CRLA) are working with state Senator Dean Flores for California legislation to establish a fund for payment of medical expenses of victims of pesticide drift, as well as programs to train emergency medical personnel, establish hazard response plans for pesticide drift incidents, and develop an online posting system for applications of drift prone pesticides in counties of heavy pesticide use.

UFW has an alert and a petition to state officials on their web site about the Arvin incident and Monitor 4, a pesticide they have been concerned about for nearly 20 years. Visit the UFW website to sign the petition at:

Sources: 11 Children on School Bus Exposed to Ag Spray, April 28, 2004, The Fresno Bee; 19 Workers Treated for Pesticide Exposure, May 2, 2004, Kings Canyon Unified School District web site,; Bakersfield Californian; Fields of Poison, PANNA, CPR, CRLA, 2002,

Contact: PANNA.

PANUPS is a weekly email news service providing resource guides and reporting on pesticide issues that don’t always get coverage by the mainstream media. It’s produced by Pesticide Action Network North America, a non-profit and non-governmental organization working to advance sustainable alternatives to pesticides worldwide.

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