PANNA: Latino Farmworkers Face Greater Risk of Cancer


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Latino Farmworkers Face Greater Risk of Cancer
July 19, 2002

A recent study by the Cancer Registry of California analyzed cancer incidence among California Latino farmworkers who had been members of the United Farmworkers of America (UFW) union. Out of more than 140,000 farmworkers, the study found that 1,001 had been diagnosed with cancer between 1973 and 1997. Compared with the general Latino population, farmworkers were more likely to develop certain types of leukemia by 59%, stomach cancer by 69%, cervical cancer by 63% and uterine cancer by 68%.

Farmworkers are regularly exposed to pesticides–while mixing or applying pesticides; during planting, weeding, thinning, irrigating, pruning, and harvesting crops; living in or near treated fields; or eating pesticide contaminated food. As a result, farmworkers face greater risk of exposure to hazardous pesticides than any other sector of society.
Pesticide exposure results in both short-term acute poisonings, including rash, headache, blurred vision, chest pain, excessive sweating, nausea and vomiting, as well as long-term or chronic illness, such as cancer, birth defects and other reproductive and developmental problems.

According to the study’s co-author Paul Mills, farmworkers were diagnosed at a later stage than most of the state’s Latinos, which reveals the lack of health care and education available to most farmworkers–a finding confirmed by a recent study of California farmworker health conducted by the California Institute for Rural Studies. Many cancers, such as uterine cancer, are more treatable with early detection.

Although the study doesn’t directly link pesticide use to the higher rates of cancer, the UFW believes there is a direct relationship between the chemicals and cancer. The study also refers to a previous analysis of leukemia incidence that showed a strong correlation with use of the pesticides atrazine, 2,4-D and captan, all of which are used in California agriculture. Mills says a follow up study will examine what pesticides were used and how long farmworkers were exposed to them.
In an attempt to refute the findings of the UFW study, a representative of the California Farm Bureau Federation cited recent reductions in reported poisonings among California farmworkers. However, those reports address only acute poisonings and, in addition, many of these poisonings are unreported. There is no centralized reporting system for most chronic pesticide-related illnesses with the exception of cancer. The Cancer Registry of California data may actually underestimate the true incidence among farmworkers since some may have worked in California but moved away, been diagnosed and treated in Mexico or never sought medical attention.

Some earlier studies support the Cancer Registry’s findings. A 1993 study found that when compared to the general population, both farmers and farmworkers have increases in multiple myeloma and cancers of the stomach, prostate and testis. In addition, farmworkers showed unique increases in cancers of the mouth, pharynx, lungs and liver, a finding which also supports the overall findings of the Cancer Registry study. In 1984, the small town of McFarland, California, gained national attention when a cancer cluster was discovered among children of farmworker parents. Eight children were diagnosed with various types of cancer. Their parents worked in the fields and had direct contact with pesticides. A more recent study used California’s pesticide use reporting system to group high-use carcinogenic pesticides and looked at intensity of use in U.S. census blocks in the state. Top-ranking pesticides were propargite, methyl bromide, and trifluralin, with more than 1 million pounds used in California in 2000. While most blocks averaged less than one pound per square mile during 1991-1994, 493 block groups registered more than 569 pounds per square mile for pesticides classified as probable human carcinogens. In 1990, approximately 170,000 children under 15 years of age were living in these blocks.

Protection from pesticide exposure ranks high among the workplace safety issues addressed by the UFW. Historically, the union has played a key role in fighting for elimination of some of the most hazardous pesticides. For example, the UFW played an important role in the fight to ban the use of DDT on U.S. farms, pushing for prohibitions of the chemical in labor contracts before it was banned by the government in 1972.

For a copy of the Cancer Registry study, visit


Agricultural Pesticide Use in California: Pesticide Prioritization, Use Densities, and Population Distributions for a Childhood Cancer Study, 2001, Environmental Health Perspectives. 109: 1071-1078; Cancer Among Migrant and Seasonal Farmworkers: an Epidemiologic Review and Research Agenda. 1993, American Journal of Industrial Medicine, 24:753-766; Cancer Incidence in the United Farmworkers of America (UFW) 1987-1997, 2001, American Journal of Industrial Medicine, 40: 596-603; Suffering in Silence: A Report on the Health of California’s Agricultural Workers, California Institute for Rural Studies, November 2000.


PANNA; United Farmworkers, National Headquarters, P.O. Box 62, Keene, California 93531; email; Web site

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