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Daily News Blog

Archive for the 'Atrazine' Category


02
Apr

Spring Planting Brings New Urgency to Atrazine Contamination

(Beyond Pesticides, April 2, 2010) On Monday, Tyrone Hayes PhD, researcher and professor at University of California Berkley gave a speech at Illinois State University urging the U.S. Environmental Protection Agency (EPA) to ban atrazine completely. Though atrazine has been the go to broad leaf weed killer for America’s corn growers since the 1950’s, evidence continues to build that atrazine is an unacceptable danger to humans and wildlife, and controversy continues as spring planting looms. In response to mounting scientific research, EPA announced last October it would review atrazine’s registration status, and last month announced plans to overhaul drinking water regulations regarding atrazine and numerous other chemicals known to harm human health. Dr. Hayes is one of the preeminent researchers on the effects of atrazine on amphibians. He compares the current loss of amphibians to the bird die-offs in the 1960’s due to DDT. The Journal Star who covered the event called the atrazine issue “one of the most contested environmental debates since PCBs were banned in the 1970s.” The debate has pitted concerned farmers, environmentalists, and human health advocates against conventional corn growers and atrazine manufacturer Syngenta. Syngenta, the Swiss chemical giant, is also facing litigation from several municipalities […]

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30
Mar

Unprecedented Pesticide Contamination Found in Beehives

(Beyond Pesticides, March 30, 2010) Searching for clues to the mysterious disappearance of bees, known as “colony collapse disorder”(CCD), Penn State University researchers have identified widespread pesticide contamination of beehives. The study, “High Levels of Miticides and Agrochemicals in North American Apiaries: Implications for Honey Bee Health,” was published March 19, 2010 in the scientific journal Public Library of Science (PLOS). The study finds 121 different types of pesticides within 887 wax, pollen, bee and hive samples from 23 states. The top 10 most frequently detected pesticides are fluvalinate, coumaphos, chlorpyrifos, chlorothalonil, amitraz, pendamethalin, endosulfan, fenpropathrin, esfenvalerate and atrazine. Miticides are the most common contaminant in the wax and bees, and fungicides are the most common contaminant of pollen. For the full results of the study, including several tables of wax, pollen and bee sample data, download the study from the PLOS website. “The pollen is not in good shape,” Chris Mullin, PhD, lead author of the study, told Discovery News. The authors state that the 98 pesticides and metabolites detected in mixtures up to 214 parts per million (ppm) in bee pollen alone represents a remarkably high level for toxicants in the brood and adult food of this primary […]

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03
Mar

More Research Links Atrazine to Sexual Abnormalities in Amphibians

(Beyond Pesticides, March 3, 2010) A recently published study in the Proceedings of the National Academy of Sciences finds that male frogs exposed to the herbicide atrazine can become so completely female that they can mate and lay viable eggs. This latest study adds to the growing scientific evidence which shows that atrazine, one of the most common herbicides used in the U.S., disrupts the development and behavior of aquatic animals, and negatively effects their immune, hormone, and reproductive systems. The study, “Atrazine induces complete feminization and chemical castration in male African clawed frogs (Xenopus laevis),” led by Tyrone Hayes, PhD, at the University of California, Berkeley, demonstrates the reproductive consequences of atrazine exposure in adult amphibians. Dr. Hayes and other researchers examined a group of 40 African clawed frogs, all of which carried male chromosomes. As tadpoles, the frogs were put in water with 2.5 parts per billion (ppb) of atrazine — a concentration within federal drinking water standards. Atrazine-exposed males were both demasculinized (chemically castrated) and completely feminized as adults. Exposed genetic males developed into functional females that copulated with unexposed males and produced viable eggs. The eggs produced were all male offspring since both parents contributed male […]

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10
Feb

Herbicide Atrazine Linked to Rare Birth Defect

(Beyond Pesticides, February 10, 2009) Living near farms that use the weed killer atrazine increases the risk of a rare birth defect, according to a study presented February 5, 2010 at the annual meeting of the Society for Maternal-Fetal Medicine in Chicago. Gastroschisis, a rare birth defect in which an infant’s intestines stick out of the body through a defect on one side of the umbilical cord, affects 1 in 5000 babies born in the U.S. each year. Babies with this condition have problems with movement and absorption in the gut, because the unprotected intestine is exposed to irritating amniotic fluid. Surgery is required to repair this defect. The rate of gastroschisis has risen 2- to 4-fold over the last three decades, especially in areas where agriculture is the primary industry, according to Sarah Waller, PhD, of the University of Washington, Seattle, and colleagues. Dr. Waller’s team studied the potential link between atrazine and the birth defect because, as they note in their conference abstract, “During the last 10 years, the highest percentage per population of gastroschisis was in Yakima County, in the eastern part of the state, where agriculture is the primary industry.” Overall, Washington state has about double […]

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08
Feb

EPA Sued for Failure to Protect Endangered Species from Pesticides

(Beyond Pesticides, February 8, 2010) The Center for Biological Diversity filed a notice of intent to sue the Environmental Protection Agency (EPA) last week. The lawsuit argues that EPA violated the Endangered Species Act when it approved 394 pesticides known to be harmful to humans and wildlife, without consulting with wildlife regulatory agencies as to the pesticides’ effects on endangered species. By registering pesticides known to harm migratory birds the EPA has also violated the Migratory Bird Treaty Act, according to the suit. The pesticides named in the suit pose a danger not only to wildlife, but to human health as well. Some of the pesticides named include 2,4-D the most commonly used pesticide in the nonagricultural sector, atrazine, triclosan, and pyrethrins. Jeff Miller, conservation advocate at the Center for Biological Diversity, said, “It’s time for the Environmental Protection Agency to finally reform pesticide use to protect both wildlife and people…Many endangered species most affected by toxic pesticides are already struggling to cope with habitat loss and rapid climate changes. For too long this agency’s oversight has been abysmal, allowing the pesticide industry to unleash a virtual plague of toxic chemicals into our environment.” The suit names 887 threatened and […]

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07
Jan

EPA Urged To Reject Biased Syngenta Studies in New Atrazine Review

(Beyond Pesticides, January 7, 2010) Family farm groups across the Midwest are calling on the U.S. Environmental Protection Agency (EPA) to prioritize independent science as the agency begins reviewing the health and environmental threats posed by the herbicide atrazine. In a letter sent to EPA Administrator Lisa Jackson on January 5, 2010, over a dozen groups maintain that only a completely transparent process that rejects biased research produced by the pesticide’s primary manufacturer, Syngenta, will result in a review that serves the interests of farmers, the general public and the environment. “As farmers on the front line of chemical exposure, we need EPA to make science-based decisions in the interest of our health, our family’s health and the health of our community,” said Paul Sobocinski, a southwest Minnesota crop and livestock farmer and Land Stewardship Project member. “Unfortunately, EPA has a track record of allowing agrichemical companies like Syngenta to hijack the process with bad science.” The letter to Ms. Jackson was accompanied by a new report, The Syngenta Corporation & Atrazine: The Cost to the Land, People & Democracy, jointly produced by the Minnesota-based Land Stewardship Project (LSP) and Pesticide Action Network North America (PANNA). The report provides farmers […]

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15
Dec

Atrazine Exposure Triggers Release of Stress Hormone

(Beyond Pesticides, December 15, 2009) Exposure to the endocrine-disrupting herbicide atrazine triggers the release of stress hormones in rats, according to a new study published in the December 2009 issue of the journal Toxicological Sciences. The researchers believe this may explain how the popular weed killer produces some its harmful reproductive effects. The study, “Characterization of the Hypothalamic-Pituitary-Adrenal Axis Response to Atrazine and Metabolites in the Female Rat,” was conducted by the Environmental Protection Agency’s (EPA) National Health and Environmental Effects Research Laboratory. According to a December 4 analysis by Environmental Health Sciences, a foundation-funded journalism organization, the researchers discovered that female rats fed atrazine at the time of ovulation released a flow of stress hormones that are known to interfere with hormones essential for reproduction. The findings reveal one way atrazine may impact female reproduction. Elevated stress hormones can disrupt the hormone signals that spur ovulation. Such a stress response to atrazine could partially explain why previous studies find that the herbicide inhibits reproduction. The stress reaction is similar to that seen when the animals are restrained against their will. One of the most widely used agricultural pesticides in the U.S., atrazine can currently legally be applied before and […]

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08
Oct

EPA Announces New Scientific Evaluation of Atrazine

(Beyond Pesticides, October 8, 2009) The U.S. Environmental Protection Agency (EPA) announced that it will launch a comprehensive new evaluation of the pesticide atrazine to determine its effects on humans this fall. At the end of this process, the agency will decide whether to revise its current risk assessment of the pesticide and whether new restrictions are necessary to better protect public health. This announcement follows recent scrutiny and findings that the current EPA regulation of atrazine in water is inadequate. In August this year, the Natural Resources Defense Council (NRDC) published a report, Poisoning the Well which found that the commonly used herbicide atrazine can spike at extremely high levels which go undetected by regular monitoring. Concurrently, The New York Times published an investigative piece based on the NRDC findings and confirmed that the public is not informed when reports of these spikes of atrazine in drinking water occur. One of the most widely used agricultural pesticides in the U.S., atrazine can currently legally be applied before and after planting to control broadleaf and grassy weeds. Its increased use to manicure home lawns and gardens has become a serious environmental concern as runoff has had severe health and environmental […]

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05
Oct

Review Confirms Atrazine Harms Fish and Amphibians

(Beyond Pesticides, October 5, 2009) An analysis of more than 100 scientific studies conducted on atrazine, published in the online edition of Environmental Health Perspectives, demonstrates the toxicity of atrazine to aquatic animals. Biologists at the University of Southern Florida (USF) have found evidence that atrazine harms fish and frogs. Atrazine is disruptive to the development and behavior of aquatic animals, and negatively effects their immune, hormone, and reproductive systems, according to the studies done by USF assistant professor Jason R. Rohr and postdoctoral fellow Krista A. McCoy. Atrazine is commonly used on lawns, golf courses, and sugarcane fields in Florida, and has recently been the topic of much controversy. While atrazine typically does not kill amphibians and freshwater fish, the USF report says it did: Ӣ Reduce the size of amphibians at or near metamorphosis in 19 of 19 studies. Ӣ Make amphibians and fish more active in 12 of 14 studies but reduced behaviors used to evade predators in six of seven studies. Ӣ Alter at least one aspect of male frogs’ reproductive development in eight of 10 studies. Ӣ Reduce the functioning of animals’ immune systems and often put them at risk of infection. Atrazine, a common […]

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29
Sep

Children Living Near Agricultural Pesticide Use Have Higher Cancer Rate

(Beyond Pesticides, September 29, 2009) A new study reveals that children exposed to agricultural pesticides applied near their home have up to twice the risk of developing the most common form of childhood leukemia, according to the Northern California Cancer Center (NCCC). The study, “Residential proximity to agricultural pesticide applications and childhood acute lymphoblastic leukemia,” published in the October issue of Environmental Research, used a unique California database to reveal an elevated risk in acute lymphoblastic leukemia (ALL) among children living near applications of certain categories of pesticides used in agriculture. The study, led by Rudolph Rull, Ph.D., shows an elevated risk of ALL associated with moderate exposure, but not high exposure, to pesticides classified as organophosphates (odds ratio (OR) 1.6), chlorophenoxy herbicides (OR 2.0), and triazines (OR 1.9), and with agricultural pesticides used as insecticides (OR 1.5) or fumigants (OR 1.7). California is one of the few states in the country that requires active reporting of pesticide applications, including time, place, and the type and amount of pesticide used. For this study, researchers were able to link children’s entire residential histories from birth to the time of case diagnosis to this pesticide-use reporting database and identify agricultural pesticides that […]

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26
Aug

Report Finds Inadequate EPA Regulation of Pesticides in Water

(Beyond Pesticides, August 26, 2009) The commonly used herbicide atrazine can spike at extremely high levels which go undetected by regular monitoring, according to new report by the Natural Resources Defense Council (NRDC), Poisoning the Well. Currently, the U.S. Environmental Protection Agency (EPA) considers an annual average atrazine level of below 3 parts per billion to be acceptable for human consumption, although studies have shown adverse health impacts below EPA’s “safe” levels. The analysis by NRDC discovered that in the 139 municipal water systems from which EPA collected data on a biweekly basis in 2003 and 2004, atrazine is found 90% of the time. Furthermore, 54 of these water systems have at least one spike above 3 parts per billion. “The data shows that EPA is unable to adequately regulate atrazine and protect the public from this hazardous herbicide in our drinking water,” said Jay Feldman, executive director of Beyond Pesticides. “With studies showing hormonal and other adverse effects at extremely low levels, any level of atrazine in our drinking water is dangerous and spikes above EPA’s 3 ppb threshold are completely unacceptable. EPA must put public health first and ban this toxic chemical.” Under the federal Safe Drinking Water […]

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10
Jul

Lawsuit to Challenge EPA for Pesticide Impacts on Polar Bears

(Beyond Pesticides, July 10, 2009) The Center for Biological Diversity notified the U.S. Environmental Protection Agency (EPA) earlier this week of its intent to file suit against the agency for failing to consider impacts to the polar bear and its Arctic habitat from toxic contamination resulting from pesticide use in the U.S. Pesticides registered by EPA for use in the U.S. are known to be transported to the Arctic via various atmospheric, oceanic, and biotic pathways. Such pesticides are biomagnified with each step higher in the food web, reaching some of their greatest concentrations in polar bears, the apex predators of the Arctic. A body of literature demonstrates the far-reaching effects of commonly used pesticides that are suspected endocrine disruptors and persistent organic pollutants, such as atrazine, 2,4-D, lindane, endosulfan, and permethrin, on global ecosystems. These pesticides, among others, and related contaminants have been linked to suppressed immune function, endocrine disruption, abnormalities in reproductive organs, hermaphroditism, and increased cub mortality in polar bears. Human subsistence hunters in the Arctic, who share the top spot on the food web with the polar bear, also face increased risks from exposure to these contaminants. “The poisoning of the Arctic is a silent crisis […]

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06
Jul

EPA Proposes Pesticides Restrictions in Endangered Species Settlement

(Beyond Pesticides, July 6, 2009) Last week, the U.S. Environmental Protection Agency (EPA) proposed to formally evaluate the harmful effects of 74 pesticides on 11 endangered and threatened species in the San Francisco Bay Area over the next five years, and to impose interim restrictions on use of these pesticides in and adjacent to endangered species habitats. The proposal stems from a settlement agreement with the Center for Biological Diversity, which sued EPA in 2007 for violating the Endangered Species Act by registering and allowing the use of toxic pesticides in Bay Area endangered species habitats without determining whether the chemicals jeopardize those species’ existence. “Tens of millions of pounds of toxic and poisonous chemicals, known to be deadly to endangered species and harmful to human health, including proven carcinogens and endocrine disruptors, are applied in the Bay Area each year, and many of those find their way through runoff or drift into our soil, creeks and rivers, San Francisco Bay, and sensitive wildlife habitats,” said Jeff Miller, conservation advocate with the Center. “The toxic stew of pesticides in the Bay-Delta has played a major role in the collapse of native fish populations, and pesticides are a leading cause of […]

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01
Apr

Birth Defects Linked to Pesticide Exposure at Time of Conception

(Beyond Pesticides, April 1, 2009) A study published in the April 2009 issue of the medical journal Acta Paediatrica reports that the highest rates of birth defects for U.S. babies arise when conception occurs during the spring and summer months, when pesticide use increases and high concentrations of pesticides are found in surface waters. The study entitled, “Agrichemicals in surface water and birth defects in the United States” is the first study to link increased seasonal concentration of pesticides in surface water with the peak in birth defects in infants conceived in the same months. Researchers analyzed all 30.1 million births in the U.S. between 1996 and 2002. A strong association between higher rates of birth defects among women whose last menstrual period was in April, May, June or July and elevated levels of nitrates, atrazine and other pesticides in surface water during those same months was found. The correlation between the month of last menstrual period and higher rates of birth defects is statistically significant for half of the 22 categories of birth defects reported in the Centers for Disease Control database from 1996 to 2002, including spina bifida, cleft lip, clubfoot and Down’s syndrome. “Elevated concentrations of pesticides […]

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12
Dec

USGS Survey Finds Low-Level Pesticides in Drinking Water

(Beyond Pesticides, December 12, 2008) A new study has found pesticides in surface waters around the United States. The U.S. Geological Survey (USGS) analyzed water from nine selected rivers, which are used as a source for public water systems and found that low levels of certain xynthetic chemicals remain in public water supplies after being treated in selected community water facilities. “Most of the man-made chemicals assessed in the USGS study are unregulated in drinking water and not required to be monitored or removed,” says Tom Jacobus, General Manager of the Washington Aqueduct. “These findings are not surprising and they will be important in helping regulators and assisting water utility managers arrive at decisions about future water treatment processes.” Scientists tested water samples for about 260 commonly used chemicals, including pesticides, solvents, gasoline hydrocarbons, personal care and household-use products, disinfection by-products, and manufacturing additives. This study did not look at pharmaceuticals or hormones. Low levels of about 130 of the synthetic chemicals are detected in streams and rivers before treatment at the public water facilities (source water). Nearly two-thirds of these chemicals are also detected after treatment. Most of the chemicals found are at levels equivalent to one thimble of […]

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17
Nov

Study Finds Low Pesticide Concentrations Can Become Toxic Mixture

(Beyond Pesticides, November 17, 2008) A toxic soup of the most commonly used pesticides frequently detected in nature can adversely affect the environment and decimate amphibian populations even if the concentration of the individual chemicals are within limits considered safe, according to University of Pittsburgh research published in the online edition of Oecologia. The results of this study build on a nine-year effort to understand potential links between the global decline in amphibians, routine pesticide use, and the possible threat to humans in the future. Amphibians are considered an environmental indicator species because of their unique sensitivity to pollutants. Their demise from pesticide exposure could foreshadow the fate of less sensitive animals, according to study author Dr. Rick Relyea, Ph.D., an associate professor of biological sciences in the University of Pittsburgh’s School of Arts and Sciences. Leopard frogs, in particular, are vulnerable to contamination; once plentiful across North America, their population has declined in recent years as pollution and deforestation has increased. Dr. Relyea exposed gray tree frog and leopard frog tadpoles to small amounts of the ten pesticides that are widely used throughout the world. Dr. Relyea selected five insecticides: carbaryl, chlorpyrifos, diazinon, endosulfan, and malathion; and five herbicides: […]

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27
Oct

Persistent Pesticides Detected in Groundwater Again

(Beyond Pesticides, October 27, 2008) Six pesticides that threaten water quality and public health continue to be detected in groundwater samples, according to a new U.S. Geological Survey (USGS) study. Published in the Journal of Environmental Quality, the study evaluates groundwater contaminants from samples taken from over 300 wells across the U.S. Over the years, frequent research has detected pesticides in ground water around the country, including in aquifers used for drinking-water supply. Over the past few decades, the use of some pesticides has been restricted or banned, while new pesticides have been introduced. One goal of the study was to track the retention of various types of contaminants that would be found in the different pesticides used over the years. Original samples were taken from the wells from 1993-1995, and compared with samples taken from 2001-2003. Laboratory analysis was performed using methods that allowed detection of pesticide compounds at concentrations as small as 1,000 times below U.S. EPA drinking-water standards. Of the 80 compounds studied, six were detected in ground water from at least 10 wells during both of those sample periods. The six pesticide compounds detected are the triazine herbicides atrazine, simazine, and prometon; the acetanilide herbicide metolachlor; […]

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23
Sep

Gender-Bending Herbicide Contaminates Lakes Far from Use Sites

(Beyond Pesticides, September 23, 2008) According to the Minnesota Department of Agriculture’s 2007 Water Quality Monitoring Report, released in August 2008, the endocrine disrupting herbicide atrazine is detected in pristine lakes in northern Minnesota far from the agricultural fields where it is applied. Metolachlor, acetochlor and dimethenamid are also frequent contaminants, according to the statewide sampling. The report, which uses data collected by a collaborative program between the U.S. Environmental Protection Agency, the Minnesota Department of Agriculture and the Minnesota Pollution Control Agency, analyzed samples from 55 of the state’s lakes. Atrazine was detected in approximately 87% of the 2007 samples, an increase from 2006. The presence of atrazine in such a large percentage of the lakes, many of which are located in non-agricultural areas of northern Minnesota, suggests widespread atmospheric deposition of this chemical (movement through wind and rain). “To some people, it is a bit of a surprise, but the concentrations are low, very low,” Steven Heiskary, a research scientist with the Minnesota Pollution Control Agency (MPCA) told the Star Tribune. Unfortunately, this is not very reassuring, given the fact that many of the developmental impacts linked to atrazine are seen at very low levels, sometimes at just […]

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17
Jul

In Agricultural Areas, Male Toads Feminized

(Beyond Pesticides, July 17, 2008) In a new study published in Environmental Health Perspectives, researchers have found an increased occurrence of intersex toads in areas with greater agricultural land cover. This points to a link between certain pesticides and endocrine disruption, a change in the hormonal balance that can have sexual and reproductive effects. Such results implicate pesticides in the decline of amphibian populations, and suggests that these chemicals are also adversely affecting humans. The study, which was conducted in south Florida, looked at cane toads, Bufo marinus, at five sites with differing land use patterns ranging from suburban to nearly completely agricultural (primarily sugarcane and vegetables). Researchers examined physical characteristics such as coloration, sexual organs, and forelimb length, as well as hormone concentrations, and found a higher rate of feminization for toads in agricultural areas. In these areas, glyphosate (the active ingredient in Round Up herbicide) and atrazine (an herbicide) use is common. Tyrone Hayes, PhD, was one of the first to document the endocrine disrupting effects of atrazine on frogs in a laboratory setting. Countering any doubts of why this work is important, Dr. Hayes said, “People often say, ”˜It is just frogs, so who cares?’ Well it […]

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03
Jul

Pesticides and Degradation Products Detected in Ground Water

(Beyond Pesticides, July 3, 2008) The results of a U.S. Geological Survey (USGS) study   investigating the occurrence of selected pesticides and their degradation products in groundwater shows that these chemicals can persist for years, depending upon the chemical structure of the compounds and the environmental conditions. The study, funded by the USGS National Water-Quality Assessment (NAWQA) Program and published in the May-June issue of Journal of Environmental Quality, specifically examines several of the factors that can influence the likelihood of pesticides and their degradation products being detected in shallow ground water, including oxidation-reduction (redox) conditions and ground water residence times, at four study sites across the United States. Numerous studies over the past four decades have established that pesticides, which are typically applied at the land surface, can move downward through the unsaturated zone to reach the water table at detectable concentrations. The downward movement of pesticide degradation products, formed in situ, can also contribute to the contamination of ground water.The study reveals that the pesticides and degradation products detected most frequently in shallow ground water samples from all four areas are predominantly from two classes of herbicides””triazines and chloroacetanilides. None of the insecticides or fungicides examined are detected […]

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10
Jun

Study Shows Real-World Pesticide Mixtures Harm Salmon

(Beyond Pesticides, June 10, 2008) According to scientists at Simon Fraser University in British Columbia, Canada, real-world pesticide combinations, such as those found in Canada’s Nicomekl River, may contribute to latest decline in the region’s endangered salmon populations. The study, published in Environmental Science and Technology (ES&T), a publication of the American Chemical Society, examines the impact by simulating the river’s low-level pesticide mixture to examine its effects on fish. The study used steelhead trout, a member of the salmon family, and found that the pesticide mix can deaden the trout’s sense of smell. This could harm the fish’s ability to avoid predators, find mates, and migrate back to sea, the researchers say, and could contribute to the threatened and endangered status of salmon species. “Most laboratory studies examine the effects of a single chemical, often at high concentrations, but real-world streams contain a mixture of chemicals at very low concentrations,” Keith Tierney, Ph.D., the study’s coauthor, told ES&T. Dr. Tierney and his colleagues re-created river water in the laboratory under controlled conditions with carefully measured levels of the 10 most frequently occurring pesticides in British Columbia’s Nicomekl River. The mixture contained four major classes of pesticides, including the commonly […]

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30
May

Study Finds Atrazine Disrupts Human Hormone Activity

(Beyond Pesticides, May 30, 2008) A recent study has linked the common herbicide atrazine with endocrine disruption in both fish and human cells. Entitled “The Herbicide Atrazine Activates Endocrine Gene Networks via Non-Steroidal NR5A Nuclear Receptors in Fish and Mammalian Cells,” the University of Califonia, San Francisco (UCSF) research examines the reaction of zebrafish to environmentally relevant levels of atrazine, and mirrors the study in human placental cells. The zebrafish, which are particularly sensitive to endocrine disruptors,  are “feminized”  in greater proportion than the unexposed control group. Fish exposed to atrazine for 48 hours at levels found in agricultural runoff produced twice as many female fish as male. “These fish are very sensitive to endocrine disrupting chemicals, so one might think of them as ‘sentinels’ to potential developmental dangers in humans,” said senior author Holly Ingraham, PhD. “These atrazine-sensitive genes are central to normal reproduction and are found in steroid producing tissues. You have to wonder about the long-term effects of exposing the rapidly developing fetus to atrazine or other endocrine disruptors.” In human cell studies, the researchers found that atrazine activates genes involved in hormone signally and steroid synthesis. “Endocrine-related cell types with a capacity for steroid generation appear […]

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10
Apr

Intersex Frogs More Common in Suburban Areas

(Beyond Pesticides, April 10, 2008) Common frogs that live in suburban areas are more likely than their rural counterparts to develop reproductive abnormalities, according to David Skelly, PhD, professor of ecology at the Yale School of Forestry and Environmental Studies. This phenomenon becomes a serious concern as the frog’s mating season begins, leaving researchers to wonder: will frogs be clear on their role in the annual ritual? Research by Dr. Skelly, soon to be published, focuses on the common green frog, Rana clamitans, within the Connecticut River Valley. A total of 233 frogs were collected from various ponds and landscapes with the river valley and among them 13 percent have abnormalities occurring in their reproductive organs. In urban areas, 18 percent of the collected frogs are intersex, and in suburban areas 21 percent. Frogs collected from agricultural areas have the lowest rate of reproductive problems with just 7 percent classified as intersex. According to Dr. Skelly, the more suburban the land cover, the more likely the abnormalities. “This is the first evidence that I think anyone has provided that agriculture is doing anything but pushing those rates higher,” remarked Dr. Skelly of the intersex phenomena. In an attempt to explain […]

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