In the first study of its kind, researchers have linked pesticide residues on food with poor semen quality. The new study adds to a growing body of evidence tying very low-level chemical exposures with reproductive and other health harms.
Scientists from Harvard University's School of Public Health found that men who ate fruits and vegetables with higher levels of pesticide residues had fewer normal sperm and a lower sperm count than men who ate produce with lower residue levels.
The findings, released this week in the journal Human Reproduction, in no way discourage overall consumption of fresh fruits and vegetables. Men who ate more of the low-residue produce had higher sperm quality than those who ate fewer fruits and vegetables overall.
The study's lead author Jorge Chavarro, an assistant professor of nutrition and epidemiology, strongly emphasized this point in Harvard's press release:
“In fact, we found that consuming more fruits and vegetables with low pesticide residues was beneficial. This suggests that implementing strategies specifically targeted at avoiding pesticide residues, such as consuming organically grown produce or avoiding produce known to have large amounts of residues, may be the way to go.”
Tools like PAN's WhatsOnMyFood.org online database helps consumers identify produce that tend to have higher levels of pesticide residues. The website makes USDA's food sampling data easily searchable, and lists the pesticides found and their known health effects. These same data were used by the Harvard researchers in the semen quality study to identify produce most likely to have high residues levels, such as conventionally grown strawberries, spinach and peppers.
Low levels matter
Many recent studies have shown that eating conventionally grown fruits and vegetables results in measurable amounts of pesticides in the body. Others have linked occupational and environmental pesticide exposures to low sperm count and other reproductive effects, including testicular cancer and reduced levels of testosterone.
Health effects of pesticide exposures from food residues, however, is a relatively new area of research — though this is a primary exposure route for most people. This is the first study to look at impacts of such exposures on semen quality.
The current science on pesticides and male fertility was summarized recently by PAN's Policy Director Kristin Schafer for the Environmental Health Policy Institute, an online forum sponsored by Physicians for Social Responsibility. Across the board, impacts of chronic low-level exposures emerged as critical:
“Endocrine-disrupting chemicals are particularly adept at interfering with reproductive health, even when exposure levels are extremely low. Some of these chemicals are structurally similar to human hormones, and can block (or put into overdrive) the body's natural system of biological signals.”
Fortunately, this is something we can change — starting now. From the grocery store and farmers market to local, state and national food and farming policies, we can make choices that support less dependence on health-harming chemicals.