Use of the herbicide glyphosate has increased significantly over the past 20 years. With this increased exposure comes increased risk of human health effects.
Since 2015, the International Agency for Research on Cancer (IARC) has classified glyphosate as a probable human carcinogen. Other studies are looking into possible associations between glyphosate exposure and endocrine disruption and adverse effects on reproductive health.
In a recent webinar hosted by the EDC Strategies Partnership, Dr. Brenda Eskenazi presented the results of a long-term study examining possible links between glyphosate exposure and liver disease and metabolic disorders. Rates of youth liver disease and metabolic disorders have increased dramatically in recent decades.
Tracking outcomes over time
Researchers for the study followed 480 mother-child pairs from pregnancy until the children turned 18. They gathered additional data through a nested case-control study, in which they examined 60 young adults with elevated levels of certain liver enzymes, and compared them with 91 young adults with normal levels of those enzymes. Elevated liver enzymes often indicate inflammation of or damage to the liver.
The mother-child pairs were enrolled and studied through the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS). This is a long-running, longitudinal birth cohort study of pesticide and other chemical exposures. This study focused on primarily farmworker families in the Salinas Valley, California, and children born between 2000 and 2002.
The researchers measured urinary levels of glyphosate and AMPA, a breakdown product of glyphosate. Urine samples were collected during pregnancy and when the children reached the ages of 5, 14, and 18. Using pesticide application data reported to the state of California, the researchers were also able to estimate the amount of glyphosate applied within a one-kilometer radius around each home from pregnancy through age 5. When the children reached the age of 18, the researchers measured liver enzyme levels and markers of metabolic syndrome.
Health effects of early life exposures
The researchers found that glyphosate exposure in early childhood may increase the risk of liver and metabolic disorders in young adults.
- Urinary markers of glyphosate and AMPA exposure in childhood were associated with elevated liver enzymes and elevated risk of metabolic syndrome.
- Living near agricultural glyphosate applications between birth and age 5 was also associated with increased risk of metabolic syndrome at age 18.
Dr. Eskenazi, who directs the Center for Environmental Research and Community Health at the University of California, Berkeley, noted in the webinar that children with liver disease and metabolic disorder are also at greater risk for other health complications: “Liver inflammation and cardio-metabolic disease in our children is going to increase their risk for liver cancer, diabetes and other metabolic and cardiovascular diseases in adulthood.”
Visit the webinar page to watch the full recording and find out more about this important research.
This organizational blog was produced by CHE's Science Writer, Matt Lilley.