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Pesticides Harm Fertility

Using chemicals to kill the bugs in your garden may wipe out more than a few unwanted pests: A new study shows that a common garden insecticide may also be harming men’s fertility.

Chlorpyrifos, which has been found in the urine of a high percentage of men in the United States, and its breakdown product, TCPY , have already been associated with small birth weight in babies, brain development problems and other neurological disorders. But now a study in the January issue of the journal Epidemiology raises new concerns. Researchers at the U.S. Centers for Disease Control and Prevention (CDC) and the University of Michigan examined urine samples from men at a fertility clinic in Massachusetts and found that the more TCPY a man had in his urine, the lower his testosterone level.

The researchers stopped short of saying that the pesticide causes lower fertility but said further testing was urgently needed to determine its harmful effects. Studies like this, showing a correlation, can never prove causation. It’s one of the limits of epidemiology.

Chlorpyrifos is a frequently used pesticide, applied to crops such as cranberries, strawberries, citrus, apples, figs, pears, cherries, peaches, grapes, almonds, broccoli, cauliflower, asparagus, corn, tomatoes, cotton, bananas, wheat, and peanuts. For many years it was a main ingredient of RAID and also found in flea collars, but has now been banned from household uses because of its toxicity to children. Researchers tracking childbirths in New York City before and after the ban observed an increase in birth weight once chlorpyrifos was removed.

Many contaminants have been implicated in reducing human fertility, including pesticides other than chlorpyrifos. High doses of a pesticide used on bananas, called DBCP, were shown to cause outright sterility. Animal studies clearly demonstrate that a number of commonly used pesticides, as well as other contaminants, can reduce male and female fertility. Human studies are harder to do, particularly for exposures comparable to what most people would experience. In situations in which many factors may contribute, the impacts of individual factors can be difficult to determine with certainty. But a body of evidence is now available to suggest that human fertility, too, is vulnerable to contaminants. Read more here:

For information from the National Fertility Association, download this PDF

To read a scientific consensus statement about infertility and contamination, go here.

To read more about this study, click here.

To learn more about chlorpyrifos, its uses and risks, click here.

To read more about this and other environmental health issues, go to www.environmentalhealthnews.org, www.ourstolenfuture.org, or www.healthandenvironment.org.