In a meta-analysis of 120 research studies released Sept. 13, The Organic Center looks at how adult farmers and farmworkers in the US are exposed to almost 1,400 approved pesticides with more than 900 active ingredients and the related health consequences. It also compares how restrictions on the use of synthetic pesticides in organic farming and reliance on other pest management strategies could improve health outcomes.
Based on this review, the report argues that Environmental Protection Agency estimates that between 1,800 and 3,000 preventable pesticide exposures to agriculture workers annually is “likely too low for a variety of reasons.”
First, the report argues, most reports are of acute pesticide poisonings and that most low-level, chronic exposures go unreported. It also underscores that most of the nation’s farmworkers likely do not report exposure because they either have limited access to healthcare, face language barriers that complicate communication or are undocumented and may fear deportation if they seek care.
Whether reported or not, long-term occupational pesticide exposure has been linked to a wide range of human health disorders, including cancer, neurodegenerative diseases, respiratory diseases and symptoms, reproductive problems and mental health disorders, according to the report.
It also argues that there is insufficient research on the health impact of chronic exposure to common pesticides, including pyrethroids, which account for more than 17% of agricultural chemical sales. The report notes that while information about long-term, low-dose exposure is still limited, recent epidemiological studies suggest they could negatively impact heart health, sperm quality and cognitive development in children through prenatal exposure.
Likewise, according to the report, there is limited but alarming studies on the impact on mammals of neonicotinoids, which are used on 90% of corn and almost 50% of soybeans grown in the US. Finally, the report calls out the limited and conflicting research on the risks of glyphosate exposure to people.
The lack of research is alarming, given “by definition, pesticides are toxic to living organisms, so it is not surprising they can also be toxic to the environment and humans,” The Organic Center says in a statement responding to the research. “While the adverse effects of pesticides on beneficial insect predators, song birds, pollinators and native plants are well documented, the unintended effects of pesticides on humans are perhaps the most concerning.”
It adds: “Farmers and farmworkers, who are exposed to pesticides at higher doses and with greater frequency than the general public and often exposed to pesticides significantly more toxic because they are restricted from use by the general public, are at the greatest risk to the serious consequences of exposure.”
Organic techniques could offer solutions
Weighing the risks of these chemicals, The Organic Center argues that the best way to ensure sustainable food security and healthy agricultural communities is to adopt methods used by organic farmers that rely on balanced ecosystems as a first line of defense against pests instead of synthetic chemicals.
For example, it notes that by skipping pesticides that kill all insects, organic farms often have higher ratios of beneficial predator insects that can better keep in check pests. In addition, the organic practice of rotating crops to improve soil health also discourages the development of pest populations that prefer to eat a specific crop.
“Planting the same crop or closely related crops in the same area season after season provides reliable food and habitat for crop pests, allowing them to establish and grow their population to create big problems for farmers,” the report explains.
Another strategy to control pests commonly used by organic farmers that does not require pesticides is the practice of intercropping – or planting more than one crop together to use their attractive or repellent properties for pest control. Intercropping also makes host plants less visible to pests, the report argues.
Planting buffers and hedgerows of trees, bushes and grasses also can help reduce pests naturally by creating an environment for pests’ natural predators to live, according to the report, which found beneficial pest predator populations were higher and pest pressure lower in “complex landscapes versus simple landscapes.”
As a last resort, organic farmers can use some pesticides, but the list is limited to 25 synthetic materials that pose little risk to human health or the environment, according to the report. And when they are used, farmers are encouraged to use them in as limited quantities as possible and apply them using appropriate safety measures.
Even though these strategies are developed for and required of organic farmers, The Organic Center emphasizes in the report, “any farmer can draw on strategies used by organic farmers to reduce their use of chemical inputs.”