Jim Gaffney, Strategy Lead, Biotech Affairs and Regulatory at DuPont Pioneer, recently posted a response to your original question regarding the President’s Cancer Panel’s Annual Report. The response is available here and included below. Gaffney’s response explores the important role the Environmental Protection Agency plays in regulating the sale and use of pesticides and a statement from the American Cancer Society that points out that the report “does not represent scientific consensus” but rather “reflects one side of a scientific debate.”
First, it’s important to note that the report you reference was criticized when it was released. Although the report claimed “the true burden of environmentally-induced (i.e., pollution) cancer has been grossly underestimated,” an ABC News reporter wrote “…it was difficult to find solid science to back that strong statement” and the American Cancer Society pointed out in a statement about the report that its conclusion “does not represent scientific consensus” but rather “reflects one side of a scientific debate.”
Second, pesticides in use today have been thoroughly evaluated for environmental and human safety. The Environmental Protection Agency (EPA) regulates the sale and use of pesticides and requires robust studies and lengthy testing to demonstrate safety before any product reaches the market. Many products on the market today have specific modes of action for a target pest. An example of a class of crop protection chemistry that is marketed by DuPont and remains popular is sulfonylurea herbicides. These herbicides are used at very low rates (often less than one-tenth of a pound per acre) and disrupt an enzymatic pathway found only in plants, and therefore have minimal impact on other organisms (e.g., humans, birds, insects). For all products, strict handling requirements are implemented to limit potential farmworker exposure and also to limit products’ potential exposure to the environment and other non–target organisms.
As for surfactants and inert ingredients that are used in these crop protection products, government regulators maintain tight control and oversight. Ingredients used in any product have undergone scrutiny and been approved by the EPA. A substantial number of studies for toxicity and non–target organisms are required before an inert ingredient is approved for use. Furthermore, various studies confirm the safety of the active ingredient combined in its formulation with the additional product components. Whenever uncertainty occurs in risk assessments, generous safety factors are employed to ensure an abundance of caution.
And finally, crop production of any type will deplete the soil of nutrients. If not added back in some way—green manure or animal manure, long periods of fallow or synthetic fertilizer—soil nutrients will be depleted and crop yields will suffer. In most of North America, crop yields have been on the increase since the 1950s, indicating that soil nutrients are not being depleted. In fact, university research has demonstrated many positive attributes of modern production agriculture. Corn production in the United States has risen from an average of around 40 bushels per acre (bu/A) in 1950 to 160 bu/A by 2009 (USDA, 2012), and in irrigated areas of the Western Cornbelt, 200 bu/A are common with efficient use of inputs, high net energy balance and limited emission of greenhouse gases (Grassini and Cassman, 2012). Intensification of the cropping system has also improved soil’s physical properties by lowering soil bulk density; improved micro-aggregation and increased porosity, thereby allowing greater water infiltration and water-holding capacity of the soil; and increased surface soil organic carbon (Petersen and Westfall, 2004). In many cropping systems of the Northern Great Plains, for example, the soils have become a carbon sink due to increasing maize yields and reduced tillage (Clay et al., 2012).