(Beyond Pesticides, January 29, 2008) University of Cambridge scientists say there may be a link between persistent organic pollutants (POPs), including pesticides, and Type 2 Diabetes. The Cambridge scientists are advocating additional research into the little understood links between environmental pollution and adult onset diabetes. In the most recent edition of the journal Lancet, Oliver Jones, Ph.D., and Julian Griffin, Ph.D., highlight the need to research the possible link between persistent organic pollutants (POPs, a group which includes many pesticides) and insulin resistance, which can lead to adult onset diabetes. In their commentary, Dr. Jones and Dr. Griffin cite peer reviewed research including that of D. Lee, et al, which demonstrated a very strong relationship between the levels of POPs in blood, particularly organochlorine compounds, and the risk of type 2 diabetes. “Of course correlation does not automatically imply causation,” says Dr. Jones. “But if there is indeed a link, the health implications could be tremendous. At present there is very limited information. Research into adult onset diabetes currently focuses on genetics and obesity; there has been almost no consideration for the possible influence of environmental factors such as pollution.” Interestingly, in the Lee study an association between obesity and […]

(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, December 17, 2007) People exposed to banned organochlorine pesticides and other toxic chemicals that persist in the environment are more likely to develop non-Hodgkin lymphoma (NHL), according to new research funded by the British Columbia Cancer Agency. The study, “Organochlorines and risk of non-Hodgkin lymphoma”, was published in the International Journal of Cancer on December 15, 2007 and is so far the largest to examine organochlorines in plasma and their link to illness. The researchers measured the levels of pesticides or pesticide metabolites and congeners of polychlorinated biphenyls (PCBs) in the blood of 880 British Columbians, half with NHL and the other half control subjects. Several pesticide analytes and a number of congeners showed a significant association with NHL. Non-Hodgkin lymphoma is the fifth most common cancer in Canada and the most common type of lymphoma. “We know that the incidence of non-Hodgkin lymphoma has been steadily rising for the past 30 years worldwide, but there hasn’t been clear evidence to explain the increase,” says Dr. John Spinelli, Ph.D., lead author and a senior scientist at the BC Cancer Agency. “Our study helps to provide answers to this puzzle by showing a strong link between these specific environmental […]

November 13, 2007) Autism is on the rise, both in prevalence and incidence, and there is growing evidence that environmental insults, such as pesticides, are linked to this developmental disability. According to the latest study, published in the October issue of Environmental Health Perspectives, children born to mothers living near fields where pesticides are applied are more likely to develop autism spectrum disorders (ASDs). The authors of “Maternal Residence Near Agricultural Pesticide Applications and Autism Spectrum Disorders among Children in the California Central Valley” compared maternal pesticide exposure for 465 children with ASDs and 6,975 children without ASDs living in the same area. The research reveals that mothers who lived within 500 meters of fields sprayed with organochlorine pesticides, specifically endosulfan and dicofol, during their first trimester of pregnancy had a six times higher chance of having children with autism compared to mothers who did not live near the fields. Mark Horton, M.D., director of the California Department of Health, said the findings are exploratory and indicate that more research of the relationship between organochlorines and ASDs is needed. (See Daily News Blog posting from July 31, 2007 for further reactions from health care officials and more details about this […]

(Beyond Pesticides, July 31, 2007) Preliminary research into birth records and pesticide data reveal that mothers who were within 500 meters of fields sprayed with organochlorine pesticides during their first trimester of pregnancy were six times higher to have children with autism compared to mothers who did not live near the fields. Scientists from the California Department of Public Health conducted the study, which is available online in Environmental Health and Perspectives, entitled, “Maternal Residence Near Agricultural Pesticide Applications and Autism Spectrum Disorders Among Children in the California Central Valley.” The study, initiated to “systemically explore the general hypothesis that residential proximity to agricultural pesticide applications during pregnancy could be associated with autism spectrum disorders in offspring,” found that 28% of the mothers studied who lived near fields in Central Valley, which were sprayed with organochlorines, such as endosulfan and dicofol, have children with autism. However, officials are quick to point out that their findings are preliminary. “We want to emphasize that this is exploratory research,” says Dr. Mark Horton, M.D., director of the California Department of Health. “We have found very preliminary data that there may be an association. We are in no way concluding that there is a […]

(Beyond Pesticides, July 9, 2007) New field and laboratory research reveals that organochlorine pesticides reduce the hatching rate of alligator eggs. This finding adds to previous studies demonstrating that pesticides cause endocrine disruption in alligators, resulting in poorly developed reproductive organs. American alligators, which were delisted from the endangered species list in the late 1980s, are still experiencing low hatching rates around contaminated wetlands. In Florida, many wetlands were converted or are adjacent to farmlands and some farmlands have been restored back into wetlands in efforts to improve ecosystem health. Agricultural runoff has altered the surrounding aquatic environments by depositing pesticide residuals and skewing nutrient levels. Organochlorine pesticides, such as chlordane, toxaphene and dieldrin, have been especially problematic due to their persistent nature. The link between pesticides and reproductive problems in alligators has been firmly established since the 1990s. University of Florida zoologist Louis Guillette, Ph.D., found pesticides are linked to smaller penises and abnormal egg development in exposed alligators. Florida Fish and Wildlife Conservation Commission official Allan Woodward has also observed fewer hatches around lakes with high pesticide levels. He reports the hatching rate has improved around Lake Apopka, a large lake in central Florida, during the last two […]

(Beyond Pesticides, July 2, 2007) Dangerous pesticides have been found in soil samples taken from the grounds of the West Brook Middle School in Paramus, New Jersey. The concentrations found exceed state safety standards and concerns are being raised over why the school took no action once it knew about the contaminants. One of the chemicals found is chlordane. Chlordane is an organochlorine classified by the EPA as a Group B2, probable human carcinogen and is also associated with adverse neurological and gastrointestinal effects. Studies also report an association between chlordane exposure and non-Hodgkins’s lymphoma. Chlordane was registered in the U.S. in 1948 and was used as a pesticide on agricultural crops and gardens until 1978 when its registered uses on food crops and other above ground uses were cancelled. In 1988, all uses of chlordane were cancelled. This pesticide however, is persistent in soil and the environment and has been found in air samples, fish tissue, and recent studies have linked organochlorines like chlordane to breast cancer. The Record, a New Jersey newspaper, commissioned the tests to be carried out by Aqua Pro-Tech Laboratories, which revealed that chlordane at 17 parts per billion were on the school’s soccer field. […]

(Beyond Pesticides, June 8, 2007) New research shows that pesticides can reduce the efficiency of nitrogen-fixing plants, impacting soil fertility and ultimately reducing crop yields. The insecticides methyl parathion, DDT and pentachlorophenol were among the chemicals found to inhibit or delay the symbiotic relationship between the legume alfalfa and rhizobia bacteria, which is crucial to nitrogen fixation. Legume crops are often cultivated to help replenish the vital soil nutrient nitrogen (N), but legumes cannot achieve this on their own — Rhizobium bacteria interacts with legumes to convert atmospheric N to nutrient compounds utilizable by plants. Legumes like alfalfa and soybeans are often included in crop rotations due to this beneficial relationship. Nitrogen fixation resulting from the symbiotic relationship between leguminous plants and species of Rhizobium bacteria is an ecological service estimated to be equivalent to $10 billion worth of synthetic N fertilizer annually. Symbiotic nitrogen fixation (SNF) reduces the need for synthetic fertilizers, which cause environmental problems such as impaired water quality. Acknowledging that SNF is both initiated and maintained by chemical signals between the host plant and the beneficial bacteria, the research team postulated that natural and synthetic chemicals could disrupt these signals. The study shows “previously undescribed in […]

(Beyond Pesticides, May 22, 2007) In a study published in the latest issue of Environmental Toxicology and Chemistry, scientists found that seafood products from southern China contain high concentrations of DDT and hexachlorocylohexane (HCH). While banned in China since 1983, humans are being exposed to organochlorine pesticides (OCP) at rates high enough to pose health threats. The study responded to high rates of DDT and HCH found in sediment, water and biota in the Pearl River delta and neighboring coast, where land is being rapidly industrialized, urbanized, and transferred from agriculture to commercial development. Researchers tested 212 seafood products, including shrimp, crabs, and mollusks, from 11 coastal cities for 21 OCPs, including DDT, HCH, heptachlor, dieldrin, and endosulfan. The highest concentrations of DDT were found in four species of shellfish, although concentrations varied widely depending on sampling location. The study reported, “These results suggest that bioaccumulation of DDTs in seafood products was highly species-specific, probably due to different feeding habits and habitats.” By taking a large sample of one indicator species, it also concluded “the coastal region of southern China is probably one of the most DDT-polluted areas in the world.” Researchers also found HCH to be more widely prevalent […]

(Beyond Pesticides, April 10, 2007) Scientists have reported several environmental estrogens can affect the immune system, promoting allergic diseases such as asthma. Researchers have observed this response using pesticides and other environmental contaminants. Focusing on six environmental estrogens (xenoestrogens), researchers were able to reveal how these contaminants affect the immune system. Using doses representative of present human exposures, these estrogen-mimics were tested on human and mouse cells. The observed effect of exposure was both an increase in speed and intensity of immune reactions. Three of the environmental estrogens tested were organochlorine pesticides or metabolites: endosulfan, dieldrin and DDE (DDT metabolite). The other contaminants included nonylphenol, a by-product of plastics manufacturing, and two PCBs. The study reveals that the accelerated and increased level of degranulation of mast cells is the mechanism that causes more severe allergic reactions than would otherwise take place. According to Environmental Health News, mast cells play a vital role in allergic reactions because they are primed by past experience with allergens to release inflammatory agents into the body, which causes an allergic reaction. If the mast cell has been primed to react to a specific allergen, it will degranulate, releasing molecules such as histamine. The more intense […]

(Beyond Pesticides, February 8, 2007) Investigators at St. Jude Children’s Research Hospital have shed new light on the suspected role of pesticides in the development of Parkinson’s disease (PD). The study, “GST expression mediates dopaminergic neuron sensitivity in experimental parkinsonism” appearing in the Proceedings of the National Academy of Sciences (January 31, 2007), illustrates the mechanism of nerve cell damage by pesticide exposure. The enzyme that prevents damage to the substantia nigra, the part of the brain where nerve cell damage associated with PD occurs, is called GST pi (“pie”). This enzyme stands like a sentry at the crossroads of several biochemical pathways, any one of which can lead to PD. GST pi protects the nerve cell from death caused by either environmental toxics, such as pesticides, or a self-destruction process called apoptosis (cell suicide), triggered by certain stressful conditions in the cell. If GST pi levels are reduced or this enzyme is overwhelmed by toxics, these nerves are at increased risk of death, according to studies in mouse models. GST pi is one of a family of similar enzymes that eliminate free radicals generated by pesticides and other chemicals. Two members of this family are present in the brain, […]

(Beyond Pesticides, January 30, 2007) Breast cancer groups across the country have a new issue to add to the repertoire of risk factors: Pesticide use. A study published online in the American Journal of Epidemiology has found a strong link between residential pesticide use and breast cancer risk in women. Responding to the study, Susan Teitelbaum, Ph.D., assistant professor in the department of community medicine at the Mount Sinai School of Medicine in New York, says the options are simple”” “Stop using pesticides.” The study, published December 13, is the first to examine the relation between breast cancer and pesticides through self-reported residential pesticide use. Using women from New York, the study looks not at one or two incidents of pesticide contact, but at the impact of lifelong pesticide use in the home, lawn and garden. Using a sample of 1,508 women who were diagnosed with breast cancer between 1996 and 1997, the study compares these women to 1,556 control subjects who were randomly selected. The results show that those women whose blood samples had higher levels of organochlorines are at an increased risk of breast cancer. Organochlorines are a broad class of chemicals, including DDT, dieldrin, and chlordane, and […]

(Beyond Pesticides, January 18, 2007) A new study conducted in Costa Rica’s mountain forests indicates that surprisingly high concentrations of pesticides are accumulating far above the low altitudes at which they are used. Previously thought to be safe from pesticides applied to distant agricultural areas, some remote mountain forests of Costa Rica were found to have pesticide levels almost ten times greater than those in low-lying areas closer to farms and plantations. The study, led by University of Toronto, Scarborough professor Frank Wania, Ph.D., measured air and soil pesticide levels at 23 sites across Costa Rica in order to produce a model to predict potential accumulation of chemicals at high altitudes. The insecticide endosulfan and the fungicide chlorothalonil were found in the largest concentrations, with up to 1 part per billion (ppb) of chlorothalonil and 3 ppb endosulfan in soil. The high concentrations can be explained by a process in which polluted air above the farms and plantations is pushed up into the mountains, where it then cools and becomes polluted rainwater or fog. The hydrophilic nature of modern pesticides makes the occurrence of this phenomenon much more likely; as Crispin Halsall, Ph.D., of Lancaster University (U.K.) explains, “Most currently […]