ENDOCRINE DISRUPTORS: Many agricultural pesticides disrupt the normal function of male hormones, according to new tests.
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Many agricultural pesticides – including some previously untested and commonly found in food – disrupt male hormones, according to new tests conducted by British scientists.
The scientists strongly recommended that all pesticides in use today be screened to check if they block testosterone and other androgens, the hormones critical to a healthy reproductive system for men and boys.
“Our results indicate that systematic testing for anti-androgenic activity of currently used pesticides is urgently required,” wrote the scientists from University of London’s Centre for Toxicology, led by Professor Andreas Kortenkamp.
Thirty out of 37 widely used pesticides tested by the group blocked or mimicked male hormones. Sixteen of the 30 had no known hormonal activity until now, while there was some previous evidence for the other 14, according to the study, published online last Thursday in the scientific journal Environmental Health Perspectives.
Most of the newly discovered hormone disruptors are fungicides applied to fruit and vegetable crops, including strawberries and lettuce. Traces of the chemicals remain in foods.
“This study indicates that, not surprisingly, there are many other endocrine disruptors that we have not yet identified or know very little about,” said Emily Barrett, a University of Rochester assistant professor in obstetrics and gynecology who was not involved in the study.
“This underlines the glaring problem that many of the chemicals that are most widely used today, including pesticides, are simply not adequately tested and may have serious long-term impacts on health and development,” said Barrett, who studies how environmental chemicals affect human reproduction.
The findings come as the U.S. Environmental Protection Agency faces opposition from the pesticide industry after expanding its Endocrine Disruptor Screening Program, which requires testing of about 200 chemicals found in food and drinking water to see if they interfere with estrogen, androgens or thyroid hormones.
None of the 16 pesticides with the newly discovered hormonal activity is included in the EPA’s program, which means they are not currently screened and there are no plans to do so.
The EPA’s program has been slow to implement, largely due to a controversy over testing methods. Environmental groups criticize the EPA, which was granted the authority by Congress in 1996, for taking so long to order manufacturers to test only a small group of chemicals. But chemical industry officials say that the tests cost up to $1 million per chemical and the techniques have not been fully validated. They also stress that positive results don't necessarily mean that the pesticides are harming human reproduction.
The British researchers screened the chemicals using in-vitro assays, which use human cells to check whether the pesticides activate or inhibit hormone receptors in cells that turn genes on and off. They are a widely accepted lab techniques. Scientists, however, are uncertain what actually happens in the human body at the concentrations of chemicals that people encounter in fruits and vegetables.
Fetuses and infants may be particularly at risk when exposed in the womb or through breast milk because the hormones control masculinization of the reproductive tract.
Some research has linked pesticides to abnormal genitals in baby boys, such as cryptorchidism and hypospadias, and decreased sperm counts in men. Male fertility is thought to be declining in many countries, and testicular cancer is increasing. Some scientists have dubbed this compilation of male disorders “testicular dysgenesis syndrome,” and suggested that hormone-disrupting environmental contaminants play a role.
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7 Comments
Add CommentThis headline is kind of dated, but always a good reminder of the consequences of human carelessness. This is nothing new and has been reported time and time again in cancer research publications among other places. The genesis and consequences of problems like those described here has been described in great detail. One good example is the excellent work done by Tyrone Hayes of UC-Berkeley, who has reported majorly distorted sex organs and poorly developed body structures of frogs exposed to the herbicide atrazine at low ppb levels. He and his collaborators have demonstrated elevated aromatase activity leading to the conversion of testosterone to estrogen and demonstrated the same mechanism in mammalian cells. In frogs, the effects ranged from cancers to hermaphoditic offspring, which is pretty scary for humans with similar enzyme activity.
Reply | Report Abuse | Link to thisThis is a problem that can be solved by crop dusting.
Reply | Report Abuse | Link to thisLocate all the offices and homes of the executives who produce these chemicals. Apply generous amounts to those areas and the problem should clear itself up in about a generation or two.
Based on this study and an interview with a University of California expert that was published a few months ago, it appears that consumers are not being adequately protected from potentially harmful chemicals. Common sense dictates that a chemical should undergo stringent analysis for toxicity BEFORE it is permitted to enter the market (and reach the consumer). The onus to demonstrate that a chemical is safe should fall on the chemical producer. But rather than assume this responsibility, the chemical producer prematurely releases its product and arrogantly exclaims, Catch me if you can!
Reply | Report Abuse | Link to thisWhy are we ignoring common sense? Why are we putting profit before people's well-being?
To learn more about this troubling topic, I intend to read the book Doubt Is Their Product: How Industry's Assault on Science Threatens Your Health by David Michaels.
Reply | Report Abuse | Link to thisBy the way, here is the link to that Ask the Experts interview.
http://www.scientificamerican.com/article.cfm?id=are-everyday-consumer-products-making-people-sick
The results of the male hormone disruption is obviously with Global effects. Boys and young men male maturity is retarded and the evidence is in their universal adolescent behavior. The open willingness to engage in interactive games that involve their genitals is normal adolescent behavior. However, for this to persist well into their late twenties and considered normal heterosexual behavior is a deficient awaking and simply discarding it as a cultural generation thing is beyond consideration. Their emotions are heighten to the point that normal functions to engage in reality is so overwhelming the resulting is stagnation.
Reply | Report Abuse | Link to thisThe one insecticide (fenitrothion) and the four fungicides identified as endocrine disruptors in this report are not the whole story. Some herbicides also disrupt male endocrines. And the common element of all of these is that these chemicals are the profitable products of chemical companies. And these companies pay huge amounts of money to "buy" Congressmen and lobby the legislative process. The EPA now is trying manfully to get a hold of this biologically disastrous situation, but they have limited resources, and the chemical companies are always coming up with more endocrine disruptors. It is money which speaks these days, and it speaks determinately. We are heading to the point when we will have our Egyptian moment. The direction is obvious; the timing is not.
Reply | Report Abuse | Link to thisIf the pesticide companies think this stuff is harmless then they should be eager to test each chemical and prove it harmless. If they are reluctant then they clearly should not be allowed to do business in the USA.
Reply | Report Abuse | Link to thisAnother consideration is that new high tech agro techniques are cutting down a lot on usage of pesticides and herbicides. This is a trend driven by agro producers because it saves a lot of money. I don't know if that applies to fungicides or not but I am hopeful that targeted application will help reduce exposure to many of these chemicals.