A new study, published in the Environmental Health by the University of Illinois, has determined that the risk of childhood cancer (leukemia, acute lymphoid and acute myeloid leukemias (AML)), increases with exposure to agricultural crop density. There was a statistically significant association for a positive relationship between crop density of dry beans and incidence of total leukemia, oats and acute myeloid leukemia, sugar beets and total leukemia and all leukemias in specific states.
The research participants included 1.6 million children and involved the analysis of incidence data for leukemias, CNS and miscellaneous intracranial and intraspinal neoplasms, and neuroblastoma and other peripheral nervous cell tumors from 2004 through 2008 for children under the age of five; from state cancer registries in Illinois, Indiana, Ohio, Michigan, and Missoura. Data for Iowa was obtained through the Surveillance, Epidemiology, and End-Results (SEER) program.
The International Classification of Childhood Cancer was used to categorize childhood cancer records into specific types of cancer. Estimates of crop acreage were available for all states for barley, corn, hay, oats, sorghum, soybeans, and wheat.
Based on state-level pesticide use data, the crops with the highest densities in the study, corn and soybeans, had the highest proportion of acres treated with pesticides in six states. The most common herbicide used on corn was atrazine and the most common herbicide used on soybeans was glyphosate. There was a suggestive association between higher density of corn and childhood leukemia in Illinois. Oats were the most associated crop with childhood cancer. The most commonly used pesticide 2,4-D, glyphosate, and MCPA is used widely through the United States. Sugar beets had the highest proportion of acreage treated with herbicides (98 %), insecticides (63 %) and fungicides (72 %).