A highly anticipated study released last week by the U.S. Department of Health & Human Services (DHHS)’s Agency for Toxic Substances and Disease Registry (ATSDR) offers stronger evidence linking glyphosate, the active ingredient in the popular weed killer Roundup, to cancer. Experts say the findings could have a reverberating effect on litigation against Roundup manufacturer Monsanto over cancer claims.
The 257-page Draft Toxicological Profile for Glyphosate assessed rodent studies and human epidemiologic research and found exposure to glyphosate was linked to an increased risk of non-Hodgkin’s lymphoma (NHL) and multiple myeloma. It also found that the association with NHL is stronger when data is adjusted for longer use of glyphosate and for longer times since exposure for cancer to develop.
ATSDR launched the study in 2015, the same year the World Health Organization’s International Agency for Research on Cancer (IARC) classified glyphosate as a probable carcinogen. But the data had not been released. Last week, the House Science Committee asked ATSDR director Patrick Breysse for an update on the report, and the information was subsequently released.
Bayer, which acquired Monsanto last year, has maintained that glyphosate is safe, even after a California jury awarded a school groundskeeper $289 million after finding Roundup was the cause of his non-Hodgkin lymphoma diagnosis. His award was later reduced to $78 million. Last month, a federal jury in San Francisco ordered Monsanto to pay a man $80 million over similar claims.
The ATSDR study also linked glyphosate exposure to developmental delays, gastrointestinal effects, kidney and liver toxicity, and eye irritation. A long-term, ongoing study by the National Cancer Institute involving more than 20,000 pesticides mentioned in the report found that those exposed to glyphosate were at an increased risk of wheezing, chronic bronchitis, and allergic asthma.
Additionally, studies on farm families also found a small link between parental exposure to glyphosate and an increased risk of neural tube defects, miscarriage, preterm birth, and small for gestational age in their children. And some studies showed that animals exposed to glyphosate early in life developed testicular lesions, decreased sperm production, elevated abnormal sperm, decreased testosterone, and skeletal malformation.
Despite the study, the ATSDR report said the associations “were statistically significant only in a few studies.”
Tina Levine, former manager of EPA’s Office of Pesticides Programs, said that while there may not be a large risk of NHL with glyphosate exposure, “it’s there based on what ATSDR has found.”
The draft of the study is available for public comment until July 8.