(Beyond Pesticides, December 18, 2009) Biologists are finding that short-term, seasonal exposure to pesticides in rivers and basins limit the growth and size of wild salmon populations. Along with the widespread deterioration of salmon habitats, these findings show that exposure to commonly used pesticides continue to detriment the recovery of the salmons’ populations. The findings can be found in the study, “A fish of many scales: extrapolating sublethal pesticide exposures to the productivity of wild salmon populations,” in the December 2009 issue of the Ecological Society of America (ESA) journal, Ecological Applications. “Major efforts are currently underway to restore Pacific salmon habitats in an effort to recover depressed populations,” says David Baldwin, Ph.D., of the National Oceanic and Atmospheric Administration (NOAA), who co-authored the study with NOAA colleagues, “However, not much research has been done to determine the importance of pollution as a limiting factor of ESA-listed species.” The researchers studied the impact of pesticides, such as diazinon and malathion, on individual salmon using pre-existing data, and then devised a model to calculate the productivity and growth rate of the population. They used several exposure scenarios to reflect realistic pesticide use across various landscapes and over time. “An important aim […]

(Beyond Pesticides, September, 15, 2009) On September 11, 2009, the Environmental Protection Agency (EPA) announced plans to place additional limitations on the use of three organophosphate pesticides ”” chlorpyrifos, diazinon and malathion ”” to protect endangered and threatened salmon and steelhead in California, Idaho, Oregon and Washington. The announcement comes in response to a series of lawsuits brought by Pacific Coast Federation of Fishermen’s Associations (PCFFA), the Northwest Coalition for Alternatives to Pesticides, and other salmon advocates, with legal representation from Earthjustice, aimed at removing toxic pesticides from salmon spawning streams throughout the northwest. In response to the litigation, the National Marine Fisheries Service (NMFS) in November of 2008 released a “biological opinion” that set forth a plan for protecting Pacific salmon and steelhead from three toxic organophosphate pesticides. That decision came after almost a decade of legal wrangling between salmon advocates led by Earthjustice and the federal government. The biological opinion prescribed measures necessary to keep these pesticides out of water and to protect salmon populations in Washington, Oregon, California, and Idaho. The announcement from EPA moves this work forward. Although the experts at NMFS recommended prohibiting aerial applications of the three pesticides within 1,000 feet of salmon waters […]

(Beyond Pesticides, May 19, 2009) Nearly six months after federal scientists began issuing restrictions to protect salmon and steelhead in the Pacific Northwest and California, the U.S. Environmental Protection Agency (EPA) has yet to take even the first step toward implementing these protections. This delay follows almost a decade of legal wrangling in which a coalition of environmental and fishing groups, led by the non-profit public interest law firm Earthjustice, won a court order. Tell EPA to stop its foot-dragging and protect salmon and steelhead from toxic pesticides. The six pesticides that scientists have reviewed so far are some of the most dangerous chemicals used today. All six””chlorpyrifos, diazinon, malathion, carbaryl, carbofuran, and methomyl””are neurotoxic and pose serious risks to both humans and wildlife. While many of these pesticides have been phased out for residential use, they continue to expose wildlife and farmworkers through their use in agriculture. Thirty-one more chemicals will undergo review by scientists at the National Marine Fisheries Service (NMFS) in the next three years. The new restrictions require EPA to prohibit application of the six pesticides in or near salmon and steelhead habitat. They also require EPA to prohibit application when the weather may cause the […]

(Beyond Pesticides, March 5, 2009) A new study published in the March 2009 issue of Environmental Health Perspectives finds that pesticide combinations cause more harm to endangered salmon than ndividual pesticide exposure. This means that single-pesticide risk assessments required by the Environmental Protection Agency (EPA) inadequately assess hazards. Mixtures of organophosphate and carbamate pesticides are commonly detected in freshwater habitats that support threatened and endangered species of Pacific salmon. According to the researchers from the National Oceanic and Atmospheric Administration (NOAA) Fisheries and Washington State University, these pesticides inhibit the activity of acetylcholinesterase (AChE) and thus have potential to interfere with behaviors that may be essential for salmon survival. The researchers measured brain AChE inhibition in juvenile coho salmon exposed to sublethal concentrations of the organophosphates diazinon, malathion, and chlorpyrifos, as well as the carbamates carbaryl and carbofuran. The pesticides were tested individually and in combination. They plotted AChE levels on a curve to determine whether the toxicologic responses to binary mixtures were additive, antagonistic (lesser than additive) effect, or synergistic (greater than additive). The authors observed addition and synergism, with a greater degree of synergism at higher exposure concentrations. Several combinations of organophosphates were lethal at concentrations that were […]

(Beyond Pesticides, February 11, 2009) Connecticut lawmakers are taking an interest in the much debated cause of a massive die-off of lobsters that has all but wiped out the state’s 40 million dollar industry, according to the Easton Courier. Fishermen and environmentalists blame the use of the insecticide malathion, a hazardous organophosphate, currently used in community mosquito eradication programs, however the state Department of Environmental Protection (DEP) argues that there is not enough scientific data to lead to the banning of the chemical. The huge die-off of lobsters began in 1999, days after towns in Fairfield County, Westchester County and Long Island, as well as New York City, sprayed malathion to kill mosquitoes carrying the West Nile virus. Also at that time, remnants of hurricane Floyd drenched the state and washed the pesticide into Long Island Sound. The DEP, however, says the storm caused many other factors that led to the mass die-off. However, the lobster population has yet to recover. State lawmakers find DEP’s position on malathion puzzling. Rep. Richard Roy (D-Milford), chair of the House Environment Committee, and Senate Assistant Majority Leader Bob Duff (D-Norwal) are questioning DEP about its efforts to restore the state’s lobster industry while […]

(Beyond Pesticides, January 9, 2009) Environmental Toxicology and Chemistry has published a study (Vol. 27(12):2496—2500) entitled “Effects of Malathion on Embryonic Development and Latent Susceptibility to Trematode Parasites in Ranid Tadpoles.” It shows that malathion used as an agricultural insecticide is responsible for interfering with the normal development of pickerel frog embryos, thus leaving them more susceptible to parasite invasion. Malathion is present in natural water sources that have been exposed to urban and agricultural runoff. This organophosphate pesticide can be applied by planes in mosquito control program, and as esult enters water from the air. Although direct lethal and sublethal effects of chemical contaminants have been documented, latent and long-term effects have been less well documented. Therefore, researchers sought to fill this knowledge gap and found, as suspected, that tadpole survival rates decreased and malformations and susceptibility to parasite encystment rates increased as a result of exposure to malathion concentrations mimicking those found in actual water sources. Tadpoles are being exposed to increasing numbers of parasites in waters that are warming as a result of global climate change, and the researchers who performed this study speculate that, as a consequence, those exposed to malathion will have weakened immune systems […]

(Beyond Pesticides, December 8, 2008) A new study by a National Institute for Occupational Safety and Health (NIOSH) researcher finds the pesticide poisoning incidence rate among U.S. agricultural workers is thirty-nine times higher than the incidence rate found in all other industries combined. The study, “Acute Pesticide Poisoning Among Agricultural Workers in the United Sates, 1998-2005,” published in the December issue of the American Journal of Industrial Medicine, is believed to be the first detailed multi-state assessment of acute pesticide poisonings among agricultural workers. From 1998 to 2005, a total of 3,271 cases of acute occupational pesticide-related illness/injury among agricultural workers were identified in ten states. According to EPA, the Worker Protection Standards are designed to reduce the risk of injury or illness to agricultural field workers resulting from exposure to pesticides. Although the WPS was expanded in 1995 and in 2005 EPA developed a new WPS How to Comply (HTC) Manual, the NIOSH findings indicate that agricultural workers continue to have an elevated risk for acute pesticide poisoning. Furthermore, female agricultural workers experienced nearly twice the risk of pesticide poisoning of male agricultural workers. The most common factors that contributed to pesticide exposure included off-target drift, early reentry into […]

(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: […]

(Beyond Pesticides, October 6, 2008) University of Pittsburgh researchers have found that the commonly used insecticide malathion can decimate tadpole populations by altering their food chain. The study, published in the October 1 edition of Ecological Applications, finds that gradual amounts of malathion that were too small to directly kill developing leopard frog tadpoles instead sparked a biological chain of events that deprived them of their primary food source. As a result, nearly half the tadpoles in the experiment did not reach maturity and would have died in nature. The results build on a nine-year effort to investigate whether there is a link between pesticides and the global decline in amphibians, which are considered an environmental indicator species because of their sensitivity to pollutants. According to the researchers, their deaths may foreshadow the poisoning of other less environmentally-sensitivespecies, including humans. According to the U.S. Environmental Protection Agency (EPA), malathion is the most commonly used insecticide in U.S. agriculture and the third most commonly used insecticide in the U.S. home and garden sector. It has been detected in the wetlands where frogs and other amphibians live. The researchers created simulated ponds from 300-gallon outdoor tanks containing wood frog and leopard frog […]

(Beyond Pesticides, September 25, 2008) Pesticides used as lice treatments can not only have extremely harmful effects on children, they are also not as effective as non- chemical treatments such as utilizing directed hot air, according to researchers. Back-to-school season often coincides with lice outbreaks, and parents should be aware of the risks involved in using lice “shampoos” that contain pesticides and informed of the viability of non-toxic alternatives. Many of the recent headlines regarding lice in schools include reference to “super lice,” which are difficult to eliminate. These lice have developed resistance to the chemicals commonly used to treat them, such as lindane, malathion and permethrin, and therefore these treatments are increasingly ineffective. Insects frequently develop resistance to pesticides, a fact that emphasizes the importance of strategies both in agriculture and public health that focus on preventing pest outbreaks and dealing with outbreaks in ways that will not lead to resistance. One such method for eliminating head lice that will not lead to resistant strains of lice is the use of hot air, which desiccates the insects and eggs, thus killing them. Researchers testing six methods of hot air application found that hot air outperforms insecticidal shampoos in killing […]

(Beyond Pesticides, August 19, 2008) Three toxic pesticides used heavily in the United States ”” chlorpyrifos, diazinon, and malathion ”” harm children and farmworkers, poison wildlife, and taint food and drinking water, and despite well-documented hazards, the Environmental Protection Agency (EPA) allows homeowners, farmers and others to use these poisons in ways that harm salmon and steelhead. Coupled with public pressure, a recent scientific analysis from the National Marine Fisheries Service (NMFS) could force EPA to adopt new restrictions on the use of these pesticides in the Pacific Northwest and California. In a draft study — called a “biological opinion” — released on July 31, 2008, NMFS concluded that chlorpyrifos, diazinon, and malathion are contaminating rivers and streams jeopardizing protected salmon and steelhead. Please urge NMFS and EPA to adopt strong measures to protect Pacific salmon from these poisons. It is their responsibility under the Endangered Species Act. Please send an email addressed to both: Jim Lecky Director of Office of Protected Resources, NMFS [email protected] James Gulliford Assistant Administrator, US EPA Headquarters [email protected] You can be sure that chemical companies are working to ensure the unabated use of their products. Make sure the voice of the public is heard. Harmful […]

(Beyond Pesticides, August 14, 2008) The first report released by the National Marine Fisheries Service (NMFS) as a result of a lawsuit (NCAP et al. v. NMFS, No. 07-1791 RSL) settlement reveal “overwhelming evidence” to suggest that the pesticides chlorpyrifos, malathion, and diazinon increase the chance of extinction for protected salmon and steelhead. The report on the three pesticides and their effects on threatened fish is the first in what is expected to be a four year review process of 37 pesticides. “These are pesticides that EPA [the Environmental Protection Agency] has swept under the rug for years. These are three that stood out as the nastiest of the (pesticides) that are still in widespread use,” said Joshua Osborne-Klein, an attorney for Earthjustice who represented the plaintiff, Northwest Coalition for Alternatives to Pesticides (NCAP). The 377-page report is clear in its conclusion that current use patterns of these three toxic pesticides threaten the salmon and steelhead protected by the Endangered Species Act, but it does not delineate the next steps to reduce the risk. A report on mitigation measures, which could include restrictions or bans, is expected in the next few months. The timing of the report coincides with other […]

(Beyond Pesticides, March 13, 2008) Exposure to certain chemicals, including pesticides and nerve agents, explains the high rates of illness in Persian Gulf War Veterans, according to a new study published in the Proceedings of the National Academy of Sciences. Veterans from the 1990-91 conflict have a higher rate of chronic, multi-symptom health problems than either non-deployed personnel or those deployed elsewhere. Symptoms routinely reported by these veterans include fatigue, muscle or joint pain, memory problems, trouble sleeping, rash and breathing problems. Due to the findings, the study author, Beatrice Golomb, M.D., Ph.D., associate professor of medicine at the University of California, San Diego School of Medicine, warns of the potential risk to civilians exposed to pesticides.“Health issues among Gulf War veterans have been a concern for nearly two decades. Now, enough studies have been conducted, and results shared, to be able to say with considerable confidence that there is a link between chemical exposure and chronic, multi-symptom health problems,” said Dr. Golomb. “Furthermore, the same chemicals affecting Gulf War veterans may be involved in similar cases of unexplained, multi-symptom health problems in the general population.”The study synthesized evidence regarding a class of chemicals known as acetylcholinesterase inhibitors (AchEs), including […]

(Beyond Pesticides, March 10, 2008) Head lice affect an estimated 12 million people in the U.S. each year, and are rapidly becoming resistant to over-the-counter and prescription medications. Researchers at the University of Massachusetts Amherst have found that ivermectin, a compound produced by soil-dwelling bacteria, was 100 percent effective in killing head lice resistant to many standard treatments. Results were published in the January 2008 edition of the Journal of Medical Entomology. Although ivermectin is not well-absorbed through the skin, some public health advocates are concerned about its use on humans for lice and scabies. The National Pediculosis Association (NPA), a non profit agency, directs parents, health care professionals and child care providers to safer head lice control options via a standardized prevention approach focusing on routine screening, early detection and thorough combing and manual removal of lice and nits. NPA promotes this as a rational strategy over chasing lice with pesticides that offer more risk than benefit and have a well-documented history of lice resistance and failure.Most products used to treat head lice contain the insecticide pyrethrum, or its synthetic cousin permethrin, as the active ingredient. Over the past two decades, resistance to these chemicals has become a serious […]

(Beyond Pesticides, February 20, 2008) Pesticides that run off agricultural land and mix in rivers and streams combine to have a greater than expected toxic effect on the salmon nervous system, according to researcher Nathaniel Scholz, PhD, a zoologist with the National Oceanic and Atmospheric Administration (NOAA) in Seattle. Dr. Scholz, who presented his findings at the symposium entitled From Kitchen Sinks to Ocean Basins: Emerging Chemical Contaminants and Human Health,  which was organized by NOAA and hosted at the American Association for the Advancement of Science (AAAS) Annual Meeting, had previously looked at the effects of individual pesticides. However, to get a more realistic idea of exposure, combinations of several pesticides were used and juvenile salmon exposed to them two at a time. The results surprised Dr. Scholz and his team. The total impact observed from combined pesticides was greater than the sum of the individual pesticides, demonstrating a synergistic effect. Some pesticides that were not deadly when tested in individual trials killed all salmon exposed to combinations. A mixture of the pesticides diazinon and malathion, exhibited the greatest synergistic effect and killed all the salmon exposed to them, even at the lowest concentrations. “It was eye opening,” Dr. […]

(Beyond Pesticides, January 31, 2008) A study to be published in the February 2008 issue of Environmental Health Perspectives finds that children who eat a conventional diet of food produced with chemical-intensive practices carry residues of organophosate pesticides that are reduced or eliminated when they switch to an organic diet. The study is entitled “Dietary Intake and Its Contribution to Longitudinal Organophosphorus Pesticide Exposure in Urban/Suburban Children” (Chensheng Lu, Dana B. Barr, Melanie A. Pearson, and Lance A. Waller) and includes authors from Rollins School of Public Health, Emory University, and the National Center for Environmental Health, Centers for Disease Control and Prevention.According to the authors, “The objective of this article is to present the data of assessing young urban/suburban children’s longitudinal exposure to OP [organophosphate] pesticides in a group [of] young children participating in the Children Pesticide Exposure Study (CPES). The results from this study identify not only the predominant source of OP pesticide exposure but also the profile of exposures in children that are vital in formulating the strategies, both from the regulatory policy and personal behavior change perspectives, in reducing children’s exposures to OP pesticides.” The study design included 23 children, male and female, from the Seattle […]

(Beyond Pesticides, January 14, 2008) Researchers at the Indian Institute of Technology (IIT) Madras have developed nanoparticles that can remove organochlorine pesticides from drinking water. These chemicals are quite persistent in the environment and difficult to remove from water. Notorious organochlorines include DDT, endosulfan, HCH (hexacholorcyclohexane) and aldrin, all of which have known health and/or environmental hazards. Many of these chemical pesticides are used heavily in agriculture and taint India’s water. Though no comprehensive national survey has been done, isolated studies show contamination of groundwater and river systems that cannot be removed by standard water filters. “Even though some of these pesticides have been banned, they are very much present in the environment. For instance, endosulfan has an environmental lifetime of 100 years,” said Thalappil Pradeep, professor of chemistry at IIT Madras. He leads the research that has shown that nanoparticles, mostly from gold, silver, copper and several oxides, are effective at removing endosulfan even at very low concentration. “Efficient chemistry at low concentration is important so that even if one molecule of the pesticide passes by, it gets removed by the nanoparticle,” said Pradeep. He holds a US and an Indian patent and has licensed part of the technology […]

(Beyond Pesticides, September 18, 2007) On September 16, 2007, researchers from the National Institute of Environmental Health Sciences presented findings to the European Respiratory Society Annual Congress in Stockholm showing that exposure to several commonly used pesticides increases the risk of asthma in farmers. Pesticide exposure is a “potential risk factor for asthma and respiratory symptoms among farmers,” lead author Dr. Jane A. Hoppin told Reuters Health. “Because grains and animals are more common exposures in agricultural settings, pesticides may be overlooked. Better education and training of farmers and pesticide handlers may help to reduce asthma risk.”The study consisted of 19,704 farmers, 441 of which had asthma. Farmers who have experienced high pesticide exposure were twice as likely to have asthma. Sixteen of the pesticides studied were associated with asthma. Coumaphos, EPTC, lindane, parathion, heptachlor, 2,4,5-TP, DDT, malathion, and phorate had the strongest effect. “This is the first study with sufficient power to evaluate individual pesticides and adult asthma among individuals who routinely apply pesticides,” Dr. Hoppin said. Asthma is a serious chronic disorder of the lungs characterized by recurrent attacks of bronchial constriction, which cause breathlessness, wheezing, and coughing. Asthma is a dangerous, and in some cases life-threatening disease. […]