25
Oct
(Beyond Pesticides, October 25, 2024) To better understand synergistic interactions between multiple stressors, researchers from the Helmholtz Centre for Environmental Research in Leipzig, Germany, analyze exposure to the pyrethroid insecticide esfenvalerate with two nonchemical environmental factors: elevated temperature and food limitation. In their recent publication in Environmental Pollution, the authors find the greatest synergistic effects when Daphnia magna (D. magna) are subjected to esfenvalerate under conditions experienced with climate change including lower food availability and increased temperature. D. magna, also known as daphnids or water fleas, are small planktonic crustaceans that represent an essential part of the food web in lakes and ponds. Impacts on populations of daphnids can lead to effects throughout multiple trophic levels that impact overall biodiversity. As the researchers state, “Global biodiversity is declining at an unprecedented rate in response to multiple environmental stressors… A key challenge is understanding synergistic interactions between multiple stressors and predicting their combined effects.†To study this, a Stress Addition Model (SAM), which predicts the cumulative effects of interacting stressors, was utilized and compared to laboratory data using 24-hour-old neonates of D. magna. The organisms were subjected to various conditions, singularly and in combination, including increased temperature, lower quantities of food, […]
Posted in Aquatic Organisms, Biodiversity, Climate Change, Ecosystem Services, Environmental Protection Agency (EPA), esfenvalerate, synergistic effects, Synthetic Pyrethroid, Synthetic Pyrethroids, United Nations, Water, Wildlife/Endangered Sp. | No Comments »
22
Feb
(Beyond Pesticides, February 22, 2023) Combining neonicotinoid insecticides with other commonly used pesticides can result in synergistic effects on honey bees, increasing toxicity more than any individual chemical could, according to research published in Scientific Reports earlier this month. The data highlight the grave inadequacy of the U.S. Environmental Protection Agency’s (EPA) process for evaluating pesticide risks. Under current regulations, EPA requires chemical manufacturers to submit data only on singular active ingredients. Yet, pesticide products may be packaged or ‘tank mixed’ with other, equally toxic pesticides without any obligation to determine the toxicity of the material that is actually being applied. Independent research is left to fill in these gaps, and the data increasingly shows that toxicity with pesticide mixtures amounts to a roll of the dice: sometimes combinations are less toxic, sometimes their toxicities are merely additive. But more often than not, pesticide mixtures result in synergistic effects that make the product significantly more toxic than either individual chemical alone. To understand how pesticide combinations are harming pollinators, scientists began with baseline data on the individual toxicity range that common pesticides pose to honey bee colonies. Research was conducted on honey bees reared in the Stoneville Wildlife Management Area […]
Posted in cypermethrin, Dimethoate, Environmental Protection Agency (EPA), esfenvalerate, Methomyl, neonicotinoids, organophosphate, Permethrin, Pollinators, tetraconazole, Thiamethoxam, Uncategorized | 1 Comment »
07
Mar
(Beyond Pesticides, March 7, 2017) Another study, published by a team of French scientists in the journal Occupational and Environmental Medicine, links childhood behavioral problems to pyrethroid insecticide exposure. Synthetic pyrethroids are a class of insecticides that have increased in use over the past decade due to assumptions that they pose fewer risks to human health than older pesticide chemistries, such as organophosphates. However, this latest study is part of a growing body of research showing that pyrethroids share similar neurocognitive health concerns as these older pesticides. . In this research, scientists investigate the interplay between pyrethroid exposure and behavioral problems through a longitudinal cohort study, which tracks levels of pyrethroid metabolites, or breakdown products, in the urine of mothers beginning between six and 19 gestational weeks and then in their children up through six years of age. Children’s behavior is measured through a screening questionnaire known as the Strengths and Difficulties Questionnaire (SDQ). SDQ measures how social a child is (altruism), whether the child has difficulty sharing problems or asking for help (internalizing disorders), as well as how defiant or disruptive a child is (externalizing disorders). The study controlled for a number of confounding factors, such as weight, education, location (rural or […]
Posted in ADHD, Alternatives/Organics, Bifenthrin, Children/Schools, contamination, Cyfluthrin, cypermethrin, Deltamethrin, Developmental Disorders, Disease/Health Effects, esfenvalerate, fluvalinate, Permethrin, Pesticide Residues, Pests, Tebuthiuron, Trifluralin, Uncategorized | No Comments »
11
Aug
(Beyond Pesticides, August 11, 2011) A combination of eleven different kinds of commonly used pyrethroids were tested on mice in a new study which found that, at real-world exposure levels, the insecticides can produce heightened toxicity that is equal to the sum of each insecticide’s individual effect. The mixture of similar-acting insecticides works by over-stimulating electronic channels in the mouse’s brain cells and eventually causing death. This study adds to the growing body of research on the toxicity of pesticide combinations in nature and showcases the need for policy change because the current risk assessment approach to regulating pesticides fails to look at chemical mixtures and synergistic effects. The U.S. Environmental Protection Agency (EPA) currently regulates on a chemical-by-chemical basis, but as this study demonstrates, interacting chemicals can have synergistic effects at very low levels, where a “chemical cocktail†of multiple interacting chemicals combine to have greater effects than expected. Pesticides can also have a cumulative “toxic loading” effect both in the immediate and long term. Researchers exposed mice brain cells to eleven different food-use pyrethroid insecticides either singly or in a mixture in the study entitled â€Additivity of pyrethroid actions on sodium influx in cerebrocortical neurons in primary culture.†[…]
Posted in Bifenthrin, Cyfluthrin, cypermethrin, Deltamethrin, esfenvalerate, Nervous System Effects, Permethrin | No Comments »
30
Mar
(Beyond Pesticides, March 30, 2010) Searching for clues to the mysterious disappearance of bees, known as “colony collapse disorderâ€(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 […]
Posted in Agriculture, Atrazine, Chemicals, Chlorothalonil, Chlorpyrifos, Coumaphos, Endosulfan, esfenvalerate, fluvalinate, Pendimethalin, Pollinators | 3 Comments »
16
Apr
(Beyond Pesticides, April 16, 2009) The U.S. Environmental Protection Agency (EPA) convened the first ever National Bed Bug Summit (April 14-15, 2009) to solicit recommendations from scientists, state and local officials, pest control operators and the general public on how to tackle the resurgence of the blood sucking insects. Bed bugs have rebounded in significant numbers for the first time since World War II, partly due to increased global travel and their increasing resistance to commonly used pesticides. Bed bug outbreaks have tripled since 2005, according to a survey of 800 pest control firms across the country, infesting apartment buildings, college dormitories, hospital wings, homeless shelters and top-rated hotels. Bedbugs outbreaks have been reported in at least 27 states, including Honolulu, San Francisco, Cincinnati, Chicago, Houston and Miami. In 2006, a Chicago woman sued a New York hotel for $20 million after suffering more than 500 bed bug bites. Persistent outbreaks are normally concentrated in low-income neighborhoods, where people cannot afford to replace or professionally clean bedding and soft furnishing. Both New York and San Francisco have passed city legislation to help control the spread of the bugs. In San Francisco, the legislation centers on landlord and tenant rights while […]
Posted in Bedbugs, esfenvalerate | No Comments »
22
Dec
(Beyond Pesticides, December 22, 2008) The U.S. EPA has filed an administrative complaint, seeking a maximum penalty of only $4,550, against a pest control company that sprayed pesticides in a couple’s home, causing the wife to die shortly thereafter. It has been more than three years since the incident took place in Florence, Oregon. Swanson’s Pest Management of Eugene, Oregon sent an employee to a home on June 29, 2005 to apply Conquer Residential Insecticide Concentrate, active ingredient esfenvalerate, and ULD BP-100 Contact Insecticide, active ingredient pyrethrin. The couple returned to their home two and a half hours later and immediately fell to the ground due to the fumes. Paramedics were called in and they too experienced respiratory distress or became ill when they entered the treated home. According to The Oregonian, Florence Kolbeck was 76 years old and died of cardiac arrest as a result of the exposure. Her husband, Fred, was hospitalized for respiratory distress. The complaint was filed following a review of Swanson’s use of the two pesticides, finding that the company failed to properly ventilate the home prior to the occupants re-entering, and improperly applied Conquer as a “space spray†at nearly three times the allowable […]
Posted in esfenvalerate, Litigation, Oregon, Pyrethrin | 3 Comments »
22
Sep
(Beyond Pesticides, September 22, 2008) A study published in the September issue of Environmental Health Perspectives finds that low-dose, short-term exposure to esfenvalerate, a synthetic pyrethroid pesticide, delays the onset of puberty in rats at doses two times lower than U.S. EPA’s stated no observable effect level (NOEL) of 2.0 mg/kg/day. Synthetic pyrethroids are used for everything from lawn care and household insecticides, to mosquito control and agriculture. There are currently 348 pesticide products registered by the U.S. EPA. The researchers conclude: “Although the exact mechanism of action is unknown at this time, we observed the effects at dosage levels below the NOEL established through chronic dietary exposure studies in rats. The U.S. EPA (1998) http://www.epa.gov/fedrgstr/EPA-PEST/1998/April/Day-29/p11372.htm stated that â€ËœThere is no evidence of additional sensitivity to young rats or rabbits following pre- or postnatal exposure to esfenvalerate.’ The present study shows that immature female rats exposed to 1.0 mg/kg/day are sensitive to this pesticide, as evidenced by their delay in the onset of puberty. Delayed pubertal onset in humans has been associated with low bone mass density (Ho and Kung 2005), and estrogen is necessary for bone mineral acquisition in both girls and boys (Yilmaz et al. 2005). Importantly, a […]
Posted in Children/Schools, Endocrine Disruption, esfenvalerate | No Comments »
