{"id":37253,"date":"2024-12-17T00:01:40","date_gmt":"2024-12-17T05:01:40","guid":{"rendered":"https:\/\/beyondpesticides.org\/dailynewsblog\/?p=37253"},"modified":"2024-12-16T11:24:38","modified_gmt":"2024-12-16T16:24:38","slug":"study-links-numerous-chemical-families-of-pesticides-to-endocrine-disrupting-effects-including-obesity","status":"publish","type":"post","link":"https:\/\/beyondpesticides.org\/dailynewsblog\/2024\/12\/study-links-numerous-chemical-families-of-pesticides-to-endocrine-disrupting-effects-including-obesity\/","title":{"rendered":"Study Links Numerous Chemical Families of Pesticides to Endocrine Disrupting Effects, Including Obesity"},"content":{"rendered":"

(Beyond Pesticides<\/em>, December 17, 2024) A systematic review of studies on pesticides as endocrine-disrupting chemicals (EDCs) on body weight, published in Biomedicines<\/em><\/a>, evaluates 36 clinical and preclinical studies and links their agricultural use to obesity. The authors, with the lead researchers from the School of Medicine and Health Sciences at Catholic University of Valencia San Vincente, Valencia, Spain, assess studies on a range of pesticides, including organophosphates, pyrethroids, neonicotinoids, and others. In addition to concluding that the EDCs promote obesity<\/a>, they report that the chemicals cause \u201cother anthropometric changes by altering lipid and glucose metabolism, modifying genes<\/a>, or altering hormone levels such as leptin.\u201d<\/p>\n

Endocrine disruption<\/a> and obesity<\/a> are public health concerns, and there is a wide body of science linking pesticide exposure to these effects (see more here<\/a>). \u201cObesity<\/a> is considered to be a worldwide pandemic that leads to an increase in medical costs and thus becomes a public health problem,\u201d the researchers share. They continue, \u201c[Obesity] is also associated with the increased production of environmental chemicals, also called environmental obesogens<\/a>, used mainly in agriculture, as disease vector control, helping to prevent harmful effects caused by fungi, bacteria, or even pests, using pesticides, insecticides, and herbicides, or endocrine disruptors<\/a> (ED), which interfere in different processes.\u201d<\/p>\n

In analyzing five human cross-sectional studies, 24 animal studies, and seven in vitro studies published since 2000, the authors investigate how environmental and dietary pesticide exposure is associated with anthropometric parameters, such as weight and body mass index (BMI), and metabolic changes that promote fat accumulation and adipogenesis (the process of creating fat cells).<\/p>\n

Within the observational human studies, the pesticides evaluated span many different chemical families. These include: 2,4,5-dichlorophenol (2,4-D<\/a> and 2,5-D, phenoxy herbicides); imidacloprid<\/a>, acetamiprid<\/a>, and clothianidin<\/a> (neonicotinoid insecticides); glyphosate<\/a> (phosphanoglycine herbicide); diuron<\/a> (dimethylurea herbicide); chlorpyrifos<\/a> (organophosphate insecticide); permethrin<\/a> (synthetic pyrethroid insecticide); mancozeb<\/a> and maneb<\/a> (ethylene bisdithiocarbamate fungicides); carbendazim<\/a> and thiophanate<\/a> (carbamate fungicides); and benomyl<\/a> (benzimidazole fungicide). The studies compare urinary concentrations of the pesticides to weight gain and obesity<\/a>. Three of the studies use data from the National Health and Nutrition Examination Survey (NHANES) for children and adolescents aged 6\u201319 years and adults aged 20\u201385 years.<\/p>\n

\u201cParticipants with obesity were found to have higher urinary concentrations of 2,4-D and 2,5-D. Higher concentrations of these pesticides were associated with increased BMI and waist circumference,\u201d the authors note. \u201cAs in children, the adult study showed a higher prevalence of obesity with higher urinary levels of 2,4-D and 2,5-D.\u201d The additional studies find that carbendazim, thiophanate, benomyl, metalaxyl<\/a>, propineb, and chlorpyrifos show a statistically significant association with obesity prevalence.<\/p>\n

In the studies on animals, 17 focus on species of mice while the other seven use rats, with nine of the 24 studies investigating chlorpyrifos<\/a>. \u201c[T]o evaluate the effect of pesticides on obesity, BMI, waist circumference, weight gain, and fat mass were the main measures used. In addition, several studies assessed biochemical parameters such as insulin levels, blood glucose, serum leptin, thyroid hormones, and lipid profile, as well as biomarkers and indicators of lipid metabolism,\u201d the researchers explain.<\/p>\n

As a result, chlorpyrifos exposure is associated with increased body mass, adiposity, impaired glucose tolerance, and insulin sensitivity in mice and rats when combined with a high-fat diet. It is also observed to alter gut microbiota<\/a>, which can have \u201ca significant effect on weight gain, serum-free lipopolysaccharide concentrations, and fasting glucose. Furthermore, this alteration could promote body weight gain, insulin resistance, and glucose intolerance,\u201d the authors say.<\/p>\n

Chlorpyrifos also alters intestinal permeability and causes an increase in lipopolysaccharide levels, \u201cwhich could induce chronic inflammation and promote the development of insulin resistance and obesity. In addition, chlorpyrifos exposure may alter leptin levels, which could be associated with increased fat deposition, and a strong correlation was found between increased leptin levels and weight gain,\u201d the researchers find.<\/p>\n

Additional effects are noted with exposure to the organophosphate malathion<\/a> (increased body weight and serum glucose levels in mice), synthetic pyrethroids bifenthrin<\/a> and permethrin<\/a> (significantly increased body weight, fat mass, and serum cholesterol levels in mice), and lambda-cyhalothrin<\/a> and cypermethrin<\/a> (increased plasma concentrations of free fatty acids, increased cholesterol, and increased hepatic triglyceride levels).<\/p>\n

In mice, exposure to the neonicotinoid imidacloprid<\/a> causes significant increases in body weight and adipose tissue, as well as increased serum glucose levels, insulin, and leptin levels, while exposure to thiamethoxam<\/a> results in \u201c[i]ncreased epididymal and retroperitoneal adipose tissue in males, increased omental adipose tissue in females, and increased adipocyte size.\u201d Both imidacloprid and thiamethoxam exposure leads to increased levels of TG [triglycerides], free fatty acids, and cholesterol in male mice.<\/p>\n

Seven in vitro studies evaluate the \u201ceffects of pesticides on the anatomy and physiology of hepatocytes and adipocytes” and the prevalence of obesity. Regarding hepatocytes, which are cells primarily in the liver that play a role in metabolism, cis-Bifenthrin is found to increase intracellular triglyceride levels in these cells after just 24 hours.<\/p>\n

Adipocytes, fat cells found in adipose tissue, experience impacts from multiple pesticides:<\/p>\n