Common Pesticides Disrupt Crucial Human Hormones
By Greg Reyneke CWS-VI
Recently, results were released from studies conducted at the School of Pharmacy’s Center for Toxicology under the auspices of the University of London. Studies evaluated in vitro reactions between mammalian cells and commonly used pesticides. Based on their testing, many common pesticides (frequently found in food as well as milk and drinking water) can disrupt testosterone production and uptake in humans and possibly even other mammals. The researchers strongly recommended that all pesticides in use today be carefully screened to check if they block testosterone, which is critical to male (and female) reproductive health and general development. Scientists, however, are uncertain what actually happens in the human body at the concentrations of chemicals that people encounter in water, fruits, vegetables, eggs, meats and milk. Fetuses and infants may be at a significantly elevated risk when exposed in the womb or through breast milk and formula. The presence of growth hormone and growth hormone releasing peptide in massive amounts in youngsters’ bodies can certainly compound the problem even further. Thirty out of 37 pesticides studied by the University of London team altered or inhibited male hormone activity, including 16 that had no previously reported hormonal effects. Most are fungicides applied to fruit and vegetable crops, including strawberries, corn, wheat, & lettuce.
“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. Funded by the European Commission, the University of London scientists selected the pesticides to test by identifying those found most often in European fruits and vegetables. They are approved for use in many countries, including the United States.
Traces of pesticides and herbicides are known to remain in fruits and vegetables; these same chemicals can migrate into the ground and contaminate groundwater while also contaminating surface water. Interestingly, certain pesticides and herbicides will travel with water vapor when it evaporates, so that the contamination can travel hundreds or even thousands of miles from where it was originally applied. The researchers noted “a clear disparity” between today’s most widely used pesticides and the current knowledge of their risks, “with the majority of the published literature focused on pesticides that are no longer registered for use in developed countries.” Of the tested compounds, the most potent in terms of blocking androgens was the insecticide fenitrothion, an organophosphate insecticide used on orchard fruits, grains, rice, vegetables and other crops.
Others with hormonal activity include fludioxonil, fenhexamid, dimethomorph and imazalil, which are all fungicides. Fungicides (chemical compounds or biological organisms used to kill or inhibit fungi or fungal spores) are often applied close to harvest, so they are frequently found as residue in food. Fungicides “are typically applied as mixtures in order to increase effectiveness and prevent development of resistant strains and therefore, human exposure to mixtures of these in vitro anti-androgens may be considerable,” wrote Kortenkamp and the other study authors, Frances Orton, Erika Rosivatz and Martin Scholze.
To learn more about pesticides, herbicides, funcicides, rodenticides, and other nasties that might be in or on your food, visit the Pesticide Action Network’s excellent resource at whatsonmyfood.org.
For six of the pesticides that showed hormonal activity for the first time, the authors said that they strongly recommend the next round of testing, using live lab animals. “Due to estimated anti-androgenic potency, current use, estimated exposure, and lack of previous data, we strongly recommend that dimethomorph, fludioxonil, fenhexamid, imazalil, ortho-phenylphenol and pirimiphos-methyl be tested for anti-androgenic effects in vivo.” For the first four pesticides, they called it “a matter of urgency.” They are used on strawberries, lettuce, grapes and other numerous fruits and vegetables in many countries around the world.
The research findings were released while the US EPA continues to face strong opposition from the pesticide industry after expanding its Endocrine Disruptor Screening Program, which mandates testing of certain chemicals found in foods and water to determine if they interfere with androgens, estrogens, or thyroid hormones.
US EPA announced the initial list of chemicals to be screened for their potential effects on the endocrine system on April 15, 2009 and the first test orders were issued on October 29, 2009. Testing will eventually be expanded to cover all pesticide chemicals. Now that screening is underway, US EPA is reviewing test order responses and making available the status or test order responses and/or any decisions regarding US EPA testing requirements.
None of the 16 pesticides with the newly discovered hormonal activity are included in US EPA’s program, which means they are not currently screened and there are no immediate plans to do so. The agency’s program has been incredibly slow to fully implement, mostly due to a longstanding dispute over analytical testing methods and selection of compounds to be tested. Environmental groups criticize US EPA for taking so long to require manufacturers to test such a small group of compounds, and chemical industry representatives contend that the tests could cost up to one million US dollars per chemical and that the techniques have not really been fully validated for repeatability and accuracy. Chemical industry representatives also stress that positive results don’t necessarily mean that the pesticides are actually harming human reproduction or development (which reminds me of the Big Tobacco arguments a few years ago). Once again, we are forced to balance long-term human health and genetic survival with cheap, plentiful supplies of food. These are difficult decisions to make, since it can mean the difference between starvation and satiety to many communities, especially in developing nations.
Some research has linked pesticide consumption to abnormally formed genitalia in baby boys, such as cryptorchidism and hypospadias, and even decreased sperm counts in men. Male fertility is reported to be declining in many countries, and testicular cancer is increasing. Some scientists have dubbed this compilation of male disorders Testicular Dysgenesis Syndrome, and suggest that man-made endocrine disrupting chemical compounds play a significant and long-lasting role. Pesticides, herbicides and other man-made contaminants are a lingering residue of our industrialized society; we will be reaping the repercussions of our rampant chemical use for decades to come. Chemicals sprayed into the air or onto the ground can linger for decades and travel far distances. The negative impact on groundwater and surface water supplies is cumulative and inevitable.
The water quality improvement industry can play a significant role in helping consumers protect themselves from immediate and future waterborne pesticide consumption by providing POU/POE water treatment systems. Many proven technologies like granular activated carbon absorption/adsorption, nanofiltration, distillation, and reverse osmosis (hyperfiltration) purification are able to address numerous chemical compounds that can be found in water. Naturally it is beyond the scope of expertise of a water quality expert to remove contaminants from food, but the old mantra “The solution to pollution is dilution” comes to mind… the more good-quality water you drink, the better job you body’s own alimentary system will do in removing unwanted contaminants consumed in food.
Consumers are becoming increasingly concerned about contaminants in the foods they eat and the water that they drink. Helping people deal with hard water is simply not good enough anymore; people look to you – the certified water specialist as a true water quality expert. You need to be able to address consumers’ concerns about emerging contaminants like pesticides, herbicides and other pollutants.
- Orton F., Rosivatz E., Scholze M., Kortenkamp A. 2011. Widely Used Pesticides with Previously Unknown Endocrine Activity Revealed as in Vitro Anti-Androgens. Environmental Health Perspectives:-. doi:10.1289/ehp.1002895
- Environmental Health Perspectives Magazine (A free resource from the US National Institutes of Health). http://ehp03.niehs.nih.gov/home.action
- USE EPA Endocrine Disruptor Screening Program – http://www.epa.gov/endo/
- Myers, John Peter, Our Stolen Future: Are We Threatening our Fertility, Intelligence and Survival? A Scientific Detective Story. Theo Colborn, Dianne Dumanoski and John Peterson
- David Steinman and Samuel S. Epstein. The Safe Shopper’s Bible: A Consumer’s Guide to Nontoxic Household Products, Cosmetics and Food.
About the author
Greg Reyneke, CWS-VI, is currently General Manager at Intermountain Soft Water in Lindon, UT and serves on the WC&P Technical Review Committee. He also serves on the advisory board of the Smart Dealer Network, a trade association dedicated to helping independent water treatment dealers succeed in today’s changing world and reach their full potential.