(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; […]

(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 […]

(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 […]

(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 […]

(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 […]

(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 […]

(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 […]

(Beyond Pesticides, March 24, 2008) Scientists at the U.S. Geological Survey (USGS) announced that they have identified ten contaminants, including pesticides, in the Potomac River, which flows through downtown Washington, DC, that could be responsible for the alarming discovery of “intersex fish,” male fish producing eggs. The suspected chemicals include: atrazine, a common herbicide used in agriculture and on lawns that is already linked to sexual abnormalities in frogs; insecticides chlorpyrifos and endosulfan; the herbicide metolachlor; and two chemicals used to add fragrance to perfumes, soaps and other products, tonalide and galaxolide. To collect the samples, USGS scientists suspended a device intended to serve as a facsimile fish in the Potomac River near the Washington, DC’s Blue Plains sewage plant. The device had a plastic-coated tube, which simulated a fish’s permeable skin, and a layer of simulated fat. According to the Washington Post, the tests on this fake fat revealed a range of potentially worrisome pollutants. Most have been found in other streams around the U.S. “The types of things we’re finding are the types of things that are associated with everyday life,” David Alvarez, a U.S. Geological Survey research chemist who analyzed samples from the Potomac told the Washington […]

(Beyond Pesticides, March 20, 2008) A 2000-2005 U.S. Geological Survey (USGS) study, Pesticide Occurrence and Distribution in the Lower Clackamas River Basin, Oregon, 2000-2005, finds a variety of pesticides in river and tributary samples, along with trace-level detections of pesticides in treated drinking-water samples collected from a drinking-water treatment plant that uses the Clackamas River as a raw-water source. While the federal government is quick to point out that detections in drinking water are below existing Environmental Protection Agency (EPA) drinking-water standards and most river samples are below the agency’s aquatic life benchmarks, studies show hazardous endocrine-disrupting and immunosuppressive effects at extremely low levels — far below EPA standards. A total of 63 pesticide compounds were detected in 119 water samples collected during storm and non-storm conditions using low-level detection methods. More pesticides were detected in the tributaries than in the Clackamas River mainstem. One or more of 15 pesticides were detected in nine of 15 samples of drinking water. Environmental and public health advocates are concerned that these results add to a pattern of contamination across the country. USGS data released in 2008, shows widespread pesticide contamination in the Chesapeake Bay watershed, and a 2004 USGS report of nationwide […]

(Beyond Pesticides, November 28, 2007) Researchers at the Centers for Disease Control (CDC) have determined that previous studies that assessed population-based exposure to atrazine were significantly and systematically underestimated. The CDC relies on the detection and analysis of only one of the twelve identified metabolites of atrazine measured in human urine samples to estimate exposure. However, after looking at multiple metabolites, researchers found that previous assessments missed most of the exposure. Atrazine mercapturate (AM), a metabolite of atrazine, was used as definitive evidence of direct atrazine exposure. General population data indicated that less than 5% of the population was exposed to atrazine-related chemicals. However, researchers at the CDC found that this research, which relied on AM detection, gives a low and misleading estimate of exposure to atrazine and atrazine- related metabolites. Published in Environmental Health and Perspectives and entitled “Assessing Exposure to Atrazine and Its Metabolites Using Biomonitoring”, the small-scale study involving 24 individuals measured nine atrazine-related metabolites in urine. The sample was organized with respect to how likely the individuals were to be exposed to atrazine: (1) high exposure (turf pesticide applicators), (2) low exposure (non-occupationally exposed people in whom atrazine mercapturate was found during a prior study) and […]

(Beyond Pesticides, September 14, 2007) Data collected by the Environmental Protection Agency (EPA) between 2003 and 2006 has found atrazine to exist in Midwest drinking water supplies at high levels. The federal monitoring data, obtained by the National Resources Defense Council (NRDC), shows increased atrazine levels in 94 of 136 water systems tested in Indiana, Ohio, Iowa, Kentucky, Minnesota, and Nebraska. Atrazine, which has been linked to cancer in numerous studies, is a common agricultural herbicide that could see increased use as demand for corn rises due to ethanol production. In 2003, EPA called it “the most heavily used herbicide in the United States.” According to NRDC’s report, EPA’s study found that nearly all 40 monitored watersheds showed levels of atrazine at levels that harm aquatic animals and habitat. Atrazine’s effect on amphibians has been well documented, and similarly serious health effects have been found in larger mammals. Chronically contaminated drinking water puts humans at the risk of exposure to similar long-term health effects. In agricultural areas of the midwest, the risk is especially high. “Kentucky’s waterways are particularly vulnerable to contamination,” said a Western Kentucky University report. “Networks of sinkholes and underground streams allow water and contaminants to flow […]

(Beyond Pesticides, August 17, 2007) The widespread presence of pesticides and other agricultural runoff has been confirmed in the world’s largest coral reef system. Degradation of the system threatens not only a natural treasure but also the region’s economy. Australia’s Great Barrier Reef is the subject of a recent report by the Great Barrier Reef Marine Park Authority. Entitled the “Annual Marine Monitoring Report 2006,” the study confirms extensive contamination in eight of the ten major tributaries into the marine park, much of which is fertilizer and pesticide runoff from the area’s farmland. Local environmental groups are calling for government protection of the reef from these pollutants, and tourism interests worry that damage to the reef will reduce the number of visitors to Australia. According to World Wildlife Foundation-Australia program leader Nick Heath, “Reducing pollution load is possible and will help us save the Reef, as well as the 60,000 tourism jobs based around the Reef.” According to the report, “Water quality in the Great Barrier Reef is principally affected by land-based activities in its adjacent catchments, including vegetation modification, grazing, agriculture, urban development, industrial development and aquaculture. Nutrients, sediments and pesticides are the pollutants of most concern for the […]

(Beyond Pesticides, August 2, 2007) According to the Associated Press (AP), a new study finds frogs in Vermont living near farms are more than twice as likely as those living elsewhere to have deformities like missing legs. Yale University ecologist David Skelly, Ph.D., told the AP he decided to look at Vermont frogs because the state has been a hot spot during the last 10 years for deformed frogs. “We went to all these wetlands and cataloged where the deformities were found, and what kind of landscapes seemed to pose higher risks, if any,” Dr. Skelly said. “The answer was, frogs growing up in proximity to agriculture were more than two times as likely to have deformities. This doesn’t say it is chemical pesticides, but you can’t credibly consider this problem of the frogs without at least evaluating whether pesticides are involved.” Richard Levey, a biologist with the Vermont Agency of Natural Resources, said two common farm chemicals, atrazine and metolachlor, had been found in trace amounts in water from wetlands where deformed frogs had been found. But he told the AP that the concentrations were far below those thought to have any effect on aquatic life. Research by Tyrone […]

(Beyond Pesticides, July 3, 2007) A scientist at the Minnesota Pollution Control Agency (MPCA) has filed a whistleblower lawsuit in federal court, arguing that he was first not allowed to share his research with a legislative panel, and then fired for it. Hydrologist Paul Wotzka, who worked for the state Agriculture Department for sixteen years before leaving to join MPCA in October, had been slated to testify about the rise in atrazine levels in Whitewater State Park, which have exceeded recommended levels for several area species. Atrazine, which has been linked to cancer, birth defects, neurotoxicity, endocrine disruption and a variety of other health and environmental effects and has been banned by the European Union, is a widely used agricultural herbicide.. Mr. Wotzka said in his lawsuit, as well as publicly, that this rise in atrazine in Minnesota waterways was due to increased row-crop agriculture in the region and the the Agriculture Department’s support of corn for ethanol. In his lawsuit, Mr. Wotzka is asking for $75,000 and to return to his position with MPCA. He claims that he was put on investigative leave, “related to missing data that is property of the State of Minnesota.” The investigative leave led […]