Schulz R, Bub S, Petschick LL, Stehle S, Wolfram J.; “Applied pesticide toxicity shifts toward plants and invertebrates, even in GM crops;” Science, 2021, 2;372(6537):81-84; DOI: 10.1126/science.abe1148.
Pesticide impacts are usually discussed in the context of applied amounts while disregarding the large but environmentally relevant variations in substance-specific toxicity. Here, we systemically interpret changes in the use of 381 pesticides over 25 years by considering 1591 substance-specific acute toxicity threshold values for eight nontarget species groups. We find that the toxicity of applied insecticides to aquatic invertebrates and pollinators has increased considerably-in sharp contrast to the applied amount-and that this increase has been driven by highly toxic pyrethroids and neonicotinoids, respectively. We also report increasing applied toxicity to aquatic invertebrates and pollinators in genetically modified (GM) corn and to terrestrial plants in herbicide-tolerant soybeans since approximately 2010. Our results challenge the claims of a decrease in the environmental impacts of pesticide use.
Andre Schütze, Pilar Morales-Agudelo, Meghan Vidal, Antonia M. Calafat, Maria Ospina.; “Quantification of glyphosate and other organophosphorus compounds in human urine via ion chromatography isotope dilution tandem mass spectrometry;” Chemosphere, 2021, 274; DOI: 10.1016/j.chemosphere.2020.129427.
Organophosphorus pesticides are the most used pesticides in the United States. Most organophosphorus pesticides are composed of a phosphate (or phosphorothioate or phosphorodithioate) moiety and a variable organic group. Organophosphorus pesticides are scrutinized by regulatory bodies and agencies because of their toxicity or suspected carcinogenicity. Upon exposure, organophosphorus pesticides and their metabolites eliminate in urine; these urinary biomarkers are useful to evaluate human exposure. We developed a method using stable isotope dilution, ion chromatography tandem mass spectrometry for quantification in urine of 6 O,O-dialkylphosphates, metabolites of organophosphorus insecticides, and glyphosate, the most used herbicide in the United States. With simple and minimal sample preparation, the analytical method is selective and sensitive (limits of detection are 0.2-0.8 μg/L), accurate (>85%) and precise (relative standard deviation <20%), depending on the analyte. To assess the suitability of the method in real exposure scenarios, we analyzed samples collected anonymously from subjects with suspected exposure to pesticides (n = 40) or who had been on an organic diet (n = 50). We detected glyphosate in 80% of subjects reporting an organic diet and in 78% of those with suspected glyphosate exposure; concentrations ranged from <0.2 to 28.6 μg/L. Median concentrations were 0.39 μg/L for the organic diet group and 0.40 μg/L for individuals with suspected exposure. Interestingly, interquartile ranges were considerably higher among those reporting pesticide exposure (0.63 μg/L) than those consuming organic diets (0.42 μg/L). These data suggest that the method meets typical validation benchmark values and is sensitive to investigate background exposures in the general population. FULL TEXT
Eunha Kim, Donggi Paik, Ricardo N. Ramirez, Delaney G. Biggs, Youngjun Park, Ho-Keun Kwon, Gloria B. Choi, Jun R. Huh.; “Maternal gut bacteria drive intestinal inflammation in offspring with neurodevelopmental disorders by altering the chromatin landscape of CD4+ T cells;” Immunity, 2022, 55(1), 145-158; 10.1016/j.immuni.2021.11.005.
Children with autism spectrum disorders often display dysregulated immune responses and related gastrointestinal symptoms. However, the underlying mechanisms leading to the development of both phenotypes have not been elucidated. Here, we show that mouse offspring exhibiting autism-like phenotypes due to prenatal exposure to maternal inflammation were more susceptible to developing intestinal inflammation following challenges later in life. In contrast to its prenatal role in neurodevelopmental phenotypes, interleukin-17A (IL-17A) generated immune-primed phenotypes in offspring through changes in the maternal gut microbiota that led to postnatal alterations in the chromatin landscape of naive CD4+ T cells. The transfer of stool samples from pregnant mice with enhanced IL-17A responses into germ-free dams produced immune-primed phenotypes in offspring. Our study provides mechanistic insights into why children exposed to heightened inflammation in the womb might have an increased risk of developing inflammatory diseases in addition to neurodevelopmental disorders. FULL TEXT
Lopez-Yañez Blanco A, Díaz-López KM, Vilchis-Gil J, Diaz-Garcia H, Gomez-Lopez J, Medina-Bravo P, Granados-Riveron JT, Gallardo JM, Klünder-Klünder M, Sánchez-Urbina R.; “Diet and Maternal Obesity Are Associated with Increased Oxidative Stress in Newborns: A Cross-Sectional Study.” Nutrients, 2022; 14(4):746; DOI:10.3390/nu14040746.
Overweight and obesity have become a world-health public problem, mainly for developing countries. Both health conditions have a higher prevalence among women of childbearing age. Physiopathology, overweight and obesity are characterized by a chronic oxidative stress status, which has deleterious effects on mothers and children. Hence, we determine whether the qualities of diet during pregnancy and maternal pregestational body mass index (BMI) are associated with increased oxidative stress markers in mothers and newborns. Two hundred forty-two (242) mother-newborn pairs were classified according to their pregestational BMI. Information on food intake was collected using a food frequency questionnaire in the third trimester of pregnancy. Levels of Malondialdehyde (MDA) and Nitric Oxide (NO) were measured in plasma from mothers at the end of the third trimester of pregnancy and from cord blood at birth. MDA and NO levels in mother–newborn pairs with maternal pregestational overweight or obesity were higher than in mother–newborn pairs with pregestational normal weight. For women (and newborns) who had a higher intake of fruit and vegetables, the levels of NO and MDA were lower. Lastly, women with pregestational obesity had lower fruit and vegetable intake during pregnancy and higher levels of oxidative stress and in their newborns. FULL TEXT
Bakke, B., De Roos, A. J., Barr, D. B., Stewart, P. A., Blair, A., Freeman, L. B., Lynch, C. F., Allen, R. H., Alavanja, M. C., & Vermeulen, R.; “Exposure to atrazine and selected non-persistent pesticides among corn farmers during a growing season;” Journal of Exposure Science & Environmental Epidemiology, 2009, 19(6), 544-554; DOI: 10.1038/jes.2008.53.
The aim was to develop quantitative estimates of farmers’ pesticide exposure to atrazine and to provide an overview of background levels of selected non-persistent pesticides among corn farmers in a longitudinal molecular epidemiologic study. The study population consisted of 30 Agricultural Health Study farmers from Iowa and 10 non-farming controls. Farmers completed daily and weekly diaries from March to November in 2002 and 2003 on pesticide use and other exposure determinants. Urine samples were collected at 10 time points relative to atrazine application and other farming activities. Pesticide exposure was assessed using urinary metabolites and diaries. The analytical limit of detection (LOD) ranged between 0.1 and 0.2 microg/l for all pesticide analytes except for isazaphos (1.5 microg/l) and diazinon (0.7 microg/l). Farmers had higher geometric mean urinary atrazine mercapturate (AZM) values than controls during planting (1.1 vs <LOD microg/g creatinine; P<0.05). AZM levels among farmers were significantly related to the amount of atrazine applied (P=0.015). Interestingly, farmers had a larger proportion of samples above the LOD than controls even after exclusion of observations with an atrazine application within 7 days before urine collection (38% vs 6%, P<0.0001). A similar pattern was observed for 2,4-D and acetochlor (92% vs 47%, P<0.0001 and 45% vs 4%, P<0.0001, respectively). Urinary AZM levels in farmers were largely driven by recent application of atrazine. Therefore, the amount of atrazine applied is likely to provide valid surrogates of atrazine exposure in epidemiologic studies. Elevated background levels of non-persistent pesticides, especially 2,4-D, indicate importance in epidemiologic studies of capturing pesticide exposures that might not be directly related to the actual application.
Baker, Brian P., Green, Thomas A., & Loker, Ali J.; “Biological control and integrated pest management in organic and conventional systems;” Biological Control, 2020, 140; DOI: 10.1016/j.biocontrol.2019.104095.
More resilient and sustainable approaches are urgently needed to minimize crop yield losses resulting from pest activity and reduce impacts of pest management on human health and the environment. Increasing implementation of biological approaches, including biological control, biopesticides, biostimulants and pheromones is a mutual high priority for sustainable agriculture leaders and practitioners, including those working in organic agriculture and Integrated Pest Management (IPM). While market and regulatory forces, and pest resistance to conventional pesticides are contributing to growth in implementation of biological approaches, they remain a very small percentage of the overall global crop protection portfolio. Barriers to greater adoption include many of the same barriers to adopting IPM techniques or transitioning to organic. Improved awareness and understanding of the histories and benefits of organic and IPM, goals and priorities shared by organic and IPM proponents and practitioners, and opportunities for accelerating adoption of biological approaches have potential to improve our combined effectiveness in overcoming these barriers. Strategies to speed adoption include increased education and extension on proven, ready-to-use biological control options; full cost and benefit accounting for biologically-based alternatives to chemical controls; and public and private sector policies to encourage biological control and reduce reliance on chemical controls. Both the organic and IPM communities of practice stand to gain from collaboration on common interests and goals. FULL TEXT
Bajwa, U., & Sandhu, K. S.; “Effect of handling and processing on pesticide residues in food- a review;” Journal of Food Science and Technology, 2014, 51(2), 201-220; DOI: 10.1007/s13197-011-0499-5.
Pesticides are one of the major inputs used for increasing agricultural productivity of crops. The pesticide residues, left to variable extent in the food materials after harvesting, are beyond the control of consumer and have deleterious effect on human health. The presence of pesticide residues is a major bottleneck in the international trade of food commodities. The localization of pesticides in foods varies with the nature of pesticide molecule, type and portion of food material and environmental factors. The food crops treated with pesticides invariably contain unpredictable amount of these chemicals, therefore, it becomes imperative to find out some alternatives for decontamination of foods. The washing with water or soaking in solutions of salt and some chemicals e.g. chlorine, chlorine dioxide, hydrogen peroxide, ozone, acetic acid, hydroxy peracetic acid, iprodione and detergents are reported to be highly effective in reducing the level of pesticides. Preparatory steps like peeling, trimming etc. remove the residues from outer portions. Various thermal processing treatments like pasteurization, blanching, boiling, cooking, steaming, canning, scrambling etc. have been found valuable in degradation of various pesticides depending upon the type of pesticide and length of treatment. Preservation techniques like drying or dehydration and concentration increase the pesticide content many folds due to concentration effect. Many other techniques like refining, fermentation and curing have been reported to affect the pesticide level in foods to varied extent. Milling, baking, wine making, malting and brewing resulted in lowering of pesticide residue level in the end products. Post harvest treatments and cold storage have also been found effective. Many of the decontamination techniques bring down the concentration of pesticides below MRL. However, the diminution effect depends upon the initial concentration at the time of harvest, substrate/food and type of pesticide. There is diversified information available in literature on the effect of preparation, processing and subsequent handling and storage of foods on pesticide residues which has been compiled in this article.
Ouidir, M., Buck Louis, G. M., Kanner, J., Grantz, K. L., Zhang, C., Sundaram, R., Rahman, M. L., Lee, S., Kannan, K., Tekola-Ayele, F., & Mendola, P.; “Association of Maternal Exposure to Persistent Organic Pollutants in Early Pregnancy With Fetal Growth;” JAMA Pediatrics, 2020, 174(2), 149-161; DOI: 10.1001/jamapediatrics.2019.5104.
IMPORTANCE: Prenatal exposure to persistent organic pollutants (POPs) has been associated with birth size, but data on fetal growth and among racially/ethnically diverse pregnant women remain scarce.
OBJECTIVES: To assess the association between maternal plasma POPs in early pregnancy and fetal growth and by infant sex and maternal race/ethnicity.
DESIGN, SETTING, AND PARTICIPANTS: This cohort study used the National Institute of Child Health and Human Development Fetal Growth Studies–Singleton cohort, which recruited nonobese, low-risk pregnant women before 14 weeks’ gestation between July 1, 2009, and January 31, 2013, in 12 community-based clinics throughout the United States. Participants self-identified their race/ethnicity, self-reported their behavioral risk factors, and were followed up throughout their pregnancy. Data were analyzed from July 31, 2018, to June 3, 2019.
EXPOSURES: Levels of 76 POPs in early gestation plasma were measured: 11 perfluoroalkyl and polyfluoroalkyl substances, 1 polybrominated biphenyl, 9 polybrominated diphenyl ethers (PBDEs), 44 polychlorinated biphenyls (PCBs), and 11 organochlorine pesticides (OCPs). The bayesian kernel machine regression method was used to examine chemical class mixtures, and generalized additive mixed model was used to analyze individual chemicals.
MAIN OUTCOMES AND MEASURES: Fourteen fetal biometrics were measured, including head circumference, abdominal circumference, and femur length, within 5 ultrasonography appointments.
RESULTS: A total of 2284 low-risk pregnant women were included: 606 women (26.5%) self-identified as white with a mean (SD) age of 30.3 (4.4) years, 589 (25.8%) as black with a mean (SD) age of 25.5 (5.5) years, 635 (27.8%) as Hispanic with a mean (SD) age of 27.1 (5.5) years, and 454 (19.9%) as Asian with a mean (SD) age of 30.5 (4.5) years. A comparison between the 75th and 25th percentile of exposure revealed that the OCP mixture was negatively associated with most fetal growth measures, with a reduction of 4.7 mm (95% CI, −6.7 to −2.8 mm) in head circumference, 3.5 mm (95% CI, −4.7 to −2.2 mm) in abdominal circumference, and 0.6 mm (95% CI, −1.1 to −0.2 mm) in femur length. Higher exposure to the PBDE mixture was associated with reduced abdominal circumference (–2.4 mm; 95% CI, −4.0 to −0.5 mm) and femur length (−0.5 mm; 95% CI, −1.0 to −0.1 mm), and the dioxin-like PCB mixture was associated with reduced head circumference (–6.4 mm; 95% CI, −8.4 to −4.3 mm) and abdominal circumference (–2.4 mm; 95% CI, −3.9 to −0.8 mm). Associations with individual chemicals were less consistent. There were some interactions by fetal sex, although most of the results did not vary by maternal race/ethnicity. For example, oxychlordane (–0.98 mm; 95% CI, –1.60 to –0.36 mm; P for interaction <.001), trans-nonachlor (–0.31 mm; 95% CI, –0.54 to –0.08 mm; P for interaction = .005), and p,p’-dichlorodiphenyldichloroethylene (–0.19 mm; 95% CI, –0.22 to –0.09 mm; P for interaction = .006) were associated with shorter femur length among boys only.
CONCLUSIONS AND RELEVANCE: This study found that, among pregnant women with low POP levels, a mixture of OCPs was negatively associated with most fetal growth measures and that mixtures of PBDEs and dioxin-like PCBs were associated with reduced abdominal circumference. These findings suggested that, although exposures may be low, associations with fetal growth are apparent.
Bailey, S. W.; “Climate change and decreasing herbicide persistence;” Pest Management Science, 2004, 60(2), 158-162; DOI: 10.1002/ps.785.
A herbicide degradation model, using real weather data for the period 1980-2001, has been used to estimate the change in persistence of autumn-applied isoproturon over this period. The results suggest that soil residues fell to the minimum for weed control on average approximately 30 days earlier over the last 5 years of this period than in the first 5 years, equivalent to a reduction of approximately 25% in the duration of weed control. This decline in persistence is attributed to increasing soil temperature. The results are discussed in relation to recent observations and predictions on climate change. The relevance of the findings to other pesticides and future weed control is considered.
Baharuddin, M. R., Sahid, I. B., Noor, M. A., Sulaiman, N., & Othman, F.; “Pesticide risk assessment: A study on inhalation and dermal exposure to 2,4-D and paraquat among Malaysian paddy farmers;” Journal of Environmental Science and Health, Part B, 2011, 46(7), 600-607; DOI: 10.1080/03601234.2011.589309.
A cross-section analytical study was conducted to evaluate the risk of pesticide exposure to those applying the Class II pesticides 2,4-D and paraquat in the paddy-growing areas of Kerian, Perak, Malaysia. It investigated the influence of weather on exposure as well as documented health problems commonly related to pesticide exposure. Potential inhalation and dermal exposure for 140 paddy farmers (handlers of pesticides) were assessed. Results showed that while temperature and humidity affected exposure, windspeed had the strongest impact on pesticide exposure via inhalation. However, the degree of exposure to both herbicides via inhalation was below the permissible exposure limits set by United States National Institute of Occupational Safety and Health (NIOSH). Dermal Exposure Assessment Method (DREAM) readings showed that dermal exposure with manual spraying ranged from moderate to high. With motorized sprayers, however, the level of dermal exposure ranged from low to moderate. Dermal exposure was significantly negatively correlated with the usage of protective clothing. Various types of deleterious health effects were detected among users of manual knapsack sprayers. Long-term spraying activities were positively correlated with increasing levels of the gamma-glutamyl transpeptidase (GGT) liver enzyme. The type of spraying equipment, usage of proper protective clothing and adherence to correct spraying practices were found to be the most important factors influencing the degree of pesticide exposure among those applying pesticides.