REFERENCES ON THE IMPACT OF PESTICIDES ON BOTH HUMANS AND ENVIRONMENT

🍎 Research around the impact of pesticides on both humans and enviroment
  • An update of the Worldwide Integrated Assessment (WIA) on systemic insecticides. Part 3: alternatives to systemic insecticides Environmental Science and Pollution Research (2021) 28:11798–11820
  • Cavalier H, Trasande L, Porta M. Exposures to pesticides and risk of cancer: Evaluation of recent epidemiological evidence in humans and paths forward. Int J Cancer. 2023 Mar 1;152(5):879-912. doi: 10.1002/ijc.34300. Epub 2022 Oct 25. PMID: 36134639; PMCID: PMC9880902.
    • While much of the recent evidence suggests causal relationships between pesticide exposure and cancer, the strongest evidence exists for acute myeloid leukemia (AML) and colorectal cancer (CRC), diseases in which the observed associations were consistent across several studies, including high-quality prospective studies and those using biomarkers for exposure assessment, with some observing dose-response relationships.
    • There is sufficient evidence to implement policies and regulatory action that limit pesticide exposure in humans and, hence, further prevent a significant burden of cancers.
    • Here, the authors provide a unique review of 63 epidemiological studies on exposure to pesticides and cancer risk in humans published from 2017 to 2021, with an emphasis on new findings, methodological approaches, and gaps in the existing literature. 
  • Chronister, B. N., Yang, K., Yang, A. R., Lin, T., Tu, X. M., Lopez-Paredes, D., … & Suarez-Lopez, J. R. (2023). Urinary glyphosate, 2, 4-D and DEET biomarkers in relation to neurobehavioral performance in Ecuadorian adolescents in the ESPINA cohort. Environmental health perspectives, 131(10), 107007.
    • Following the introduction of N-(phosphonomethyl) glycine (glyphosate)-resistant “Roundup ready” crops in 1996 and 2,4-dichlorophenoxyacetic acid (2,4-D)-resistant crops in 2014, there has been a global 15-fold increase in glyphosate use and a substantial increase in 2,4-D use, making them the most widely used herbicides in the world.1,2 2,4-D is a broadleaf herbicide, which mimics auxin and kills dicotyledon (dicots) without affecting monocotyledon (monocots),3 allowing agricultural users to selectively target weeds. Glyphosate is a nonselective, broad-spectrum herbicide that targets the enzyme 5-enolpyruvyl-3-shikimate phosphate synthase and is slow acting.4–6 It is generally used in agriculture to control vegetation by damaging growth or by acting as a desiccant
    • We assessed 519 participants (11–17 years of age) living in agricultural communities in Ecuador. We quantified urinary concentrations of glyphosate, 2,4-D, and two N,N-diethyl-meta-toluamide (DEET) insect repellent metabolites 
    • This study describes worse neurobehavioral performance associated with herbicide exposures in adolescents, particularly with 2,4-D.
  • EPA releases draft biological evaluations for Atrazine, Simazine and Propazine. EPA. Published November 5, 2020.
  • Gama, J, et al. Chronic effects of dietary pesticides on the gut microbiome and Neurodevelopment. Frontiers in microbiology. Published June 30, 2022
  • Gore, A et al. Endocrine Disrupting Chemicals: Threats to Human Health. Report by the Endocrine Society. Website. Published Feb 2024.  Accessed Feb 2024. https://www.endocrine.org/-/media/endocrine/files/advocacy/edc-report2024finalcompressed.pdf
    • Exposure to chlorpyrifos occurs from agricultural and household use, use on livestock and pets, and through residues in food and water. It can result from spray drift, and inhalation of air and dust in vehicles, homes, and childcare centers and other buildings in which it is used. A survey of schoolchildren in Chile found that 80% of them had metabolites of chlorpyrifos in their urine, and this was associated with eating fruits and vegetables 
    • There is no question, however, that based on the critical and broad effects of the environment on cancer prevalence and manifestation, minimizing chemical exposures will have  a tremendous positive impact on cancer risk and survival. 
    • Although the diseases and disorders associated with EDC exposures are diverse, many of them have in common increased inflammation and underlying immune system problems. Inflammation is at the heart of a wide range of chronic diseases including obesity, cognitive and behavioral deficits, cardiovascular disease, respiratory disorders, reproductive disorders, and cancers. The immune and endocrine systems often work together in responding to environmental challenges (80) and to protect against inflammation. Related to this is the potential of EDCs to affect the gut microbiome (81, 82), which comprises an ecosystem of microbes (bacteria, fungi, protozoans, archaea, and viruses) that colonize the digestive system and assist with protecting against pathogens (83). The microbiome is important for the body’s immune function; when compromised, as can happen due to EDC exposures, inflammation and illness may ensue (84, 85)
  • Kay, J. E., Brody, J. G., Schwarzman, M., & Rudel, R. A. (2024). Application of the key characteristics framework to identify potential breast carcinogens using publicly available in vivo, in vitro, and in silico data. Environmental Health Perspectives, 132(1), 017002.
    • Chemicals that induce mammary tumors in rodents or activate estrogen or progesterone signaling are likely to increase breast cancer (BC) risk. Identifying chemicals with these activities can prompt steps to protect human health.
    • Induction of mammary tumors in rodents is one useful proxy for identifying chemicals that increase BC risk in humans given that many of the target tissue structures (e.g., terminal ductal units) and pathways that lead to mammary tumors (hormonal activity, genotoxicity) are conserved between species.8
    • We also included pesticides identified as having induced mammary tumors based on the US EPA OPP Registration Eligibility Decision (RED) and risk assessment documents as described in Cardona and Rudel 202
    • These MCs with endocrine-disrupting and genotoxic properties include several widely used pesticides (malathion, parathion, atrazine, simazine, and ametryn), endogenous and synthetic hormones (E2, estriol, estrone, 17-α α-ethinylestradiol, P4, diethylstilbestrol, and mestranol), and dye components 
    • Prenatal and early life exposure to EDCs can alter mammary gland development in humans and animals in ways that raise BC risk.
    • We consider these genotoxic EDCs,  (Endocrine disrupting chemicals) which include several widely used pesticides and dye components, to be strong candidates for regulation based on their mechanistic activities and also priorities for in vivo or epidemiological investigation as possible breast carcinogens, especially the strongest EDCs.
  • La Merrill, M. A., Krigbaum, N. Y., Cirillo, P. M., & Cohn, B. A. (2020). Association between maternal exposure to the pesticide dichlorodiphenyltrichloroethane (DDT) and risk of obesity in middle age. International journal of obesity, 44(8), 1723-1732.
    • These data indicate maternal DDT exposure is significantly associated with increased obesity risk among middle-aged women independent of the obesity definition, confounding, and obesity risk factors. 
    • Maternal o,p’-DDT was positively associated with a 26% (95% CI: 6-49) to 31% (95% CI: 6-62) higher risk of overweight and the same magnitude of additional risk for obesity, based on waist circumference and BMI definitions respectively, in multivariable models.
  • Lenox K. Connecting Parkinson’s disease, pesticides, and genes (Environmental Factor, December 2019). National Institute of Environmental Health Sciences. Published 2019.
  • A Thorny Problem: Glyphosate and 2,4-D Associated with Neurobehavioral Effects for Ecuadorian Adolescents, Environmental Health Perspectives, 10.1289/EHP14169, 131, 12, (2023).
    • Following the introduction of N-(phosphonomethyl) glycine (glyphosate)-resistant “Roundup ready” crops in 1996 and 2,4-dichlorophenoxyacetic acid (2,4-D)-resistant crops in 2014, there has been a global 15-fold increase in glyphosate use and a substantial increase in 2,4-D use, making them the most widely used herbicides in the world.1,2 2,4-D is a broadleaf herbicide, which mimics auxin and kills dicotyledon (dicots) without affecting monocotyledon (monocots),3 allowing agricultural users to selectively target weeds. Glyphosate is a nonselective, broad-spectrum herbicide that targets the enzyme 5-enolpyruvyl-3-shikimate phosphate synthase and is slow acting.4–6 It is generally used in agriculture to control vegetation by damaging growth or by acting as a desiccant
    • We assessed 519 participants (11–17 years of age) living in agricultural communities in Ecuador. We quantified urinary concentrations of glyphosate, 2,4-D, and two N,N-diethyl-meta-toluamide (DEET) insect repellent metabolites
    • This study describes worse neurobehavioral performance associated with herbicide exposures in adolescents, particularly with 2,4-D.
  • LĂłpez SL, Aiassa D, BenĂ­tez-Leite S, et al. Pesticides used in south American GMO-based agriculture. In: Advances in Molecular Toxicology. 2012:41-75.
  • Lushchak VI, Matviishyn TM, Husak VV, Storey JM, Storey KB. Pesticide toxicity: a mechanistic approach. EXCLI J. 2018;17:1101-1136. Published 2018 Nov 8.
  • Matich, E. K., Laryea, J. A., Seely, K. A., Stahr, S., Su, L. J., & Hsu, P. C. (2021). Association between pesticide exposure and colorectal cancer risk and incidence: A systematic review. Ecotoxicology and environmental safety, 219, 112327.
    • However, certain pesticides such as terbufos, dicamba, trifluralin, S-ethyl dipropylthiocarbamate (EPTC), imazethapyr, chlorpyrifos, carbaryl, pendimethalin, and acetochlor are of great concern not only for their associated elevated risk of CRC, but also for the current legal usage in the United States (US). Aldicarb and dieldrin are of moderate concern for the positive associations with CRC risk, and also for the illegal usage or the detection on imported food products even though they have been banned in the US. Pesticides can linger in the soil, water, and air for weeks to years and, therefore, can lead to exposure to farmers, manufacturing workers, and those living in rural communities near these farms and factories. 
    • The CRC mortality rate is still increasing in the rural regions despite the overall decreasing of incidence and mortality of CRC elsewhere. Therefore, the results from this study on the relationship between pesticide exposure and CRC risk will help us to understand CRC health disparities.
  • National Center for Biotechnology Information. PubChem compound summary for CID 15910, Chlorothalonil.
  • Nebeker R. Consumers are concerned about glyphosate residue. So why is it still in so many products? FoodPrint. Published August 12, 2020. Accessed October 14, 2021.
  • Taylor, L. Exploring the case against GE foods. The integrative RDN. 2014;16(4)
  • Tudi, M., Daniel Ruan, H., Wang, L., Lyu, J., Sadler, R., Connell, D., Chu, C., & Phung, D. T. (2021). Agriculture Development, Pesticide Application and Its Impact on the Environment. International journal of environmental research and public health, 18(3), 1112.
    • About one-third of agricultural products are produced depending on the application of pesticides. Without the use of pesticides, there would be a 78% loss of fruit production, a 54% loss of vegetable production, and a 32% loss of cereal production. Therefore, pesticides play a critical role in reducing diseases and increasing crop yields worldwide. 
    •  They can also be toxic to other organisms, including birds, fish, beneficial insects, and non-target plants, as well as air, water, soil, and crops. Moreover, pesticide contamination moves away from the target plants, resulting in environmental pollution. Such chemical residues impact human health through environmental and food contamination.
  • Tu P, Chi L, Bodnar W, et al. Gut microbiome toxicity: Connecting the environment and Gut Microbiome-associated diseases. Toxics. 2020;8(1):19.

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