28
Jun
Pesticides Linked to Adult and Childhood Cancer in Western U.S., with Incidence Varying by County
(Beyond Pesticides, June 28, 2022) There is a strong connection between pesticide use and cancer rates in the Western United States, finds research recently published by scientists at University of Idaho and Northern Arizona University. Two studies (here and here) published in the peer-reviewed journal GeoHealth used geospatial data and publicly available pesticide databases to uncover the relationship between chemical heavy agricultural practices and cancer in both adults and children. As the rate of chronic diseases like cancer continue to increase in the United States, and more and more studies find these diseases to be pesticide-induced, it is imperative for the public to put increased pressure on regulators and lawmakers to enact meaningful measures that eliminate pesticide use and the hazards these chemicals pose.
Of the two studies conducted by the research team, the first study modeled the connection between pesticide use and cancer incidence for adults and children in 11 western states (Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming), while the second study focuses on childhood cancer rates in Idaho’s 44 counties. Both studies utilized databases established by public entities, including U.S. Geological Survey (USGS) Pesticide National Synthesis Project database, EPA Pesticide Industry Sales and Usage Estimates, National Cancer Institute (NCI) State Cancer Profiles, and the Cancer Data Registry of Idaho. Rather than focus solely on the impacts of pesticide use to farmers or agricultural workers, the studies consider the broader effects of agricultural pesticide use on the public at large.
For the first study, researchers took the top 25 most used pesticides identified by EPA estimates, and cross-referenced them with USGS data to determine the amount of each pesticide used by state and county. These data were then modeled against NCI county-level cancer incidence.
At the state level, an association is found between the total amount of all pesticides evaluated and both overall and pediatric cancer incidence. Delving deeper into specific pesticide types, a strong connection is found between the amount of fumigants applied in each state and the rate of pediatric cancers. Specifically, the fumigant pesticide metam sodium has a strong connection between its higher use and total cancer rate. These findings are even more prevalent at the county-level. A cutting edge model regarding fumigant use and cancer rate matches quite closely to currently observed cancer rates in the over 450 counties that comprise the 11 western states.
Notably, the areas where fumigant use is high are those with more vegetable and fruit production, rather than grain crops like corn and soy. Regarding the cancer connection to fumigant use, study co-author Naveen Joseph, PhD says, “We have not seen it expressed in a fumigant like this before, and it’s absolutely striking.”
The second study by this research team likewise aimed to create a model able to describe county-level childhood cancer rates. Focusing in on Idaho’s 44 counties, researchers this time used groundwater contamination, as recorded by the Idaho Department of Water Resources, as a variable and proxy for children’s environmental exposures. The same 25 pesticides as the first study were reviewed, but researchers also included other environmental toxins like heavy metals, and nitrate/nitrites. These data are consolidated into an Environmental Burden Index (EBI), and overall environmental contamination within each county is subsequently deemed as either low, medium, or high on the EBI.
The model finds that EBI correlates closely with the pediatric cancer rate. Idaho counties with high scores on the EBI have higher rates of childhood cancer. As the study further notes, “The variables predominantly contributing to the environmental burden index were pesticides.” Like the first study, a model created by the researchers using these available data was able to accurately predict pediatric cancer incidence currently occurring in Idaho counties.
Geospatial mapping is providing new insights into the hazards presented by pesticide use, uncovering trends in public health that are systemic, yet rarely considered. Case in point is a study published in 2020, which looks at the connection between Parkinson’s disease, agricultural pesticide use, and one’s zip code in Louisiana. That study found that Parkinson’s rates are significantly higher in zip codes with commercial forests, woodlands, and pastures where the pesticides 2,4-D, chlorpyrifos, and paraquat were often sprayed.
As with other systemic injustices, one’s zip code and place of residence often determines one’s destiny. Uncovering this information and relating it to the public is of critical importance, but oftentimes those in disaffected communities are well aware of the dangers and threats they are exposed to daily. What is needed is action.
With pesticide use, we have enough evidence to know that we should be rapidly embracing time-tested, organic approaches to farming and land care that do not utilize toxic pesticides. Data elucidating the public health ills produced by pesticides must be accompanied by meaningful action from regulators and lawmakers at every level – local, state, and federal. For assistance in changing pesticide practices in your community, reach out to Beyond Pesticides at [email protected]
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source: University of Idaho press release, GeoHealth (First study, Second Study)
