(Beyond Pesticides, April 11, 2013) A report released Tuesday by the California Department of Pesticide Regulation (DPR) lays out an “Action Plan” to reduce farmer’s reliance on toxic soil fumigants. The plan was created by the Nonfumigant Strawberry Production Working Group, which was made up of scientists, growers, and other specialists. The working group was assembled in April 2012 because of the health and environmental concerns posed by the continued use of soil fumigants in strawberry production. The working group was asked to develop an action plan of research priorities for developing nonfumigant management strategies. However, even as the working group acknowledged the health and environmental risks posed by the continued use of fumigants, the plan remained conservative in its recommendations; it concluded that, “Even with full commitment to implement this action plan, the strawberry industry will need to continue its use of fumigants for years to remain viable in California,” even though growing strawberries organically without the use of fumigants has been shown to be effective.
The working group was most concerned about the continued use of methyl bromide. Historically methyl bromide has been used as a fumigant to eliminate the threat of soil borne pests. Methyl bromide has nominally been banned in industrialized countries by international treaty. The ban, which was included as part of the Montreal Protocol on Ozone Depleting Substances, is legally binding on all signatories to the treaty, of which the United States is one, having signed in 1987. It is also banned under federal law, as outlined in the Clean Air Act. These laws mandate that the substance be phased out according to a precise schedule, with 100% phase-out to be achieved by January 1, 2005. However, due to the “critical use exemption” (CUE) stipulation of the laws, which allows the chemical to continue to be used when there are no feasible alternatives, application rates have remained persistently high.
The report acknowledges that methyl bromide application has severe health impacts. According to the action plan, “Since 2003, DPR has documented hundreds of acute illnesses caused by accidental fumigant exposure to agricultural workers as well as people living near fumigated fields.” Methyl bromide has been linked to cancer, endocrine disruption, neurotoxicity and developmental problems.
Growers have tried to substitute other fumigants for methyl bromide. However, these substitutes can also have severe negative health and environmental impacts. Methyl iodide, for example, is known to cause miscarriages, thyroid dysfunction, and cancer but was approved by California state pesticide regulators in 2010 as an alternative to methyl bromide. In 2011 environmental groups sued the State of California for approving the agricultural use of methyl iodide. The use of this chemical was short lived and as of January, 1 2013 Arsta Life Science North America is no longer permitted manufacture the product.
The working group has recommended that further research be conducted on expanded breeding for genetic resistance to soil borne pests, soil health, and production methods. The working group found that there is little industry support for genetically engineered strawberries due to negative public perception and limits on exports to many countries. The plan also points out straw berry growers need more economic support to transition to non-fumigant alternatives. The reports suggested this could be done through grants or crop insurance.
The plan also pointed to certain organic production methods. One method that it studied was anaerobic soil disinfestation (ASD). This method gives growers the ability to nurture populations of soil borne microbial organisms to favor strawberry growing without fumigants. The plan also called for the evaluation of short and long term crop rotation methods that have been used in organic production.
Though the plan highlights some organic production methods it wrongly argues that fumigants would still be needed for economically viable strawberry production. After reviewing the alternative stand-alone replacement non-fumigant options the working group found these methods lack the cost effectiveness, broad efficacy, and reliability of methyl bromide. According to the plan, “Working group members recommend continuing to research the most promising options that focus on fitting these into an integrated pest management (IPM) program.”
Though this plan is a strong step in moving away from toxic fumigants it does not fully acknowledge the alternatives that already exists in organic production. A 2010 study, entitled Fruit and Soil Quality of Organic and Conventional Strawberry Agro-ecosystems, shows organic strawberry farming results in higher quality fruit and healthier soils. To compare conventional and organic strawberry production researchers selected 13 pairs of conventional and organic strawberry fields in Watsonville, CA, the state’s dominant strawberry growing region. Researchers found organically produced strawberries, while slightly smaller than conventional have higher antioxidant activity, longer shelf life, and fared better in taste tests. Soils on the organic farms are also healthier with higher organic matter concentration and greater microbial biodiversity.
A 2012 study also found that organic farming practices in strawberry production result in much greater pollination success than chemical-intensive methods. The results “suggest that organic farming could enhance the pollination service in agricultural landscapes, which is important for developing a sustainable agriculture. The method made it possible to measure the pollination independent of landscape composition, soil-type and other factors that can affect pollination success.”
The only way to know that you are not being exposed to hazardous soil fumigants is to buy organically produced food. Beyond Pesticides advocates for the national conversion to organic systems planning, which moves chemicals off the market quickly and replaces them with green management practices. To learn more about organic agriculture please visit Beyond Pesticides organic agriculture page.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.