De Roos et al., 2003
A J De Roos, S Zahm, K Cantor, D Weisenburger, F Holmes, L Burmeister, and A Blair, “Integrative assessment of multiple pesticides as risk factors for non-Hodgkin’s lymphoma among men,” Occupational and Environmental Medicine, 2003, 60:9, DOI: 10.1136/oem.60.9.e1
ABSTRACT:
METHODS: During the 1980s, the National Cancer Institute conducted three case-control studies of NHL in the midwestern United States. These pooled data were used to examine pesticide exposures in farming as risk factors for NHL in men. The large sample size (n = 3417) allowed analysis of 47 pesticides simultaneously, controlling for potential confounding by other pesticides in the model, and adjusting the estimates based on a prespecified variance to make them more stable.
RESULTS: Reported use of several individual pesticides was associated with increased NHL incidence, including organophosphate insecticides coumaphos, diazinon, and fonofos, insecticides chlordane, dieldrin, and copper acetoarsenite, and herbicides atrazine, glyphosate, and sodium chlorate. A subanalysis of these “potentially carcinogenic” pesticides suggested a positive trend of risk with exposure to increasing numbers.
CONCLUSION: Consideration of multiple exposures is important in accurately estimating specific effects and in evaluating realistic exposure scenarios. FULL TEXT
Band et al., 2011
Band PR, Abanto Z, Bert J, Lang B, Fang R, Gallagher RP, Le ND., “Prostate cancer risk and exposure to pesticides in British Columbia farmers,” Prostate, 2011, 71:2, DOI: 10.1002/pros.21232.
ABSTRACT:
BACKGROUND: Several epidemiologic studies have reported an increased risk of prostate cancer among farmers. Our aim was to assess the risk of developing prostate cancer in relation to exposure to specific active compounds in pesticides.
METHOD: A case-control approach was used with 1,516 prostate cancer patients and 4,994 age-matched internal controls consisting of all other cancer sites excluding lung cancer and cancers of unknown primary site. Lifetime occupational history was obtained through a self-administered questionnaire and used in conjunction with a job exposure matrix to estimate the participants’ lifetime cumulative exposure to approximately 180 active compounds in pesticides. Conditional logistic regression was used to assess prostate cancer risk, adjusting for potential confounding variables and effect modifiers. These include age, ethnicity, alcohol consumption, smoking, education, and proxy respondent.
RESULTS AND CONCLUSIONS: The significant association between prostate cancer risk and exposure to DDT (OR = 1.68; 95% CI: 1.04-2.70 for high exposure), simazine (OR = 1.89; 95% CI: 1.08-3.33 for high exposure), and lindane (OR = 2.02; 95% CI: 1.15-3.55 for high exposure) is in keeping with those previously reported in the literature. We also observed a significant excess risk for several active ingredients that have not been previously reported in the literature such as dichlone, dinoseb amine, malathion, endosulfan, 2,4-D, 2,4-DB, and carbaryl. Some findings in our study were not consistent with those reported in the literature, including captan, dicamba, and diazinon. It is possible that these findings showed a real association and the inconsistencies reflected differences of characteristics between study populations.
Waddell et al., 2001
Waddell BL, Zahm SH, Baris D, Weisenburger DD, Holmes F, Burmeister LF, Cantor KP, Blair A., “Agricultural use of organophosphate pesticides and the risk of non-Hodgkin’s lymphoma among male farmers (United States).,” Cancer Causes Control, 2001, 12:6.
ABSTRACT:
OBJECTIVE: Data from three population-based case-control studies conducted in Kansas, Nebraska, Iowa, and Minnesota were pooled to evaluate the relationship between the use of organophosphate pesticides and non-Hodgkin’s lymphoma (NHL) among white male farmers.
METHODS: The data set included 748 cases of non-Hodgkin’s lymphoma and 2236 population-based controls. Telephone or in-person interviews were utilized to obtain information on the use of pesticides. Odds ratios (OR) adjusted for age, state of residence, and respondent status, as well as other pesticide use where appropriate, were estimated by logistic regression.
RESULTS: Use of organophosphate pesticides was associated with a statistically significant 50% increased risk of NHL, but direct interviews showed a significantly lower risk (OR = 1.2) than proxy interviews (OR = 3.0). Among direct interviews the risk of small lymphocytic lymphoma increased with diazinon use (OR = 2.8), after adjustment for other pesticide exposures.
CONCLUSIONS: Although we found associations between the risk of NHL and several groupings and specific organophosphate pesticides, larger risks from proxy respondents complicate interpretation. Associations, however, between reported use of diazinon and NHL, particularly diffuse and small lymphocytic lymphoma, among subjects providing direct interviews are not easily discounted.
Cabello et al., 2001
Gertrudis Cabello, Mario Valenzuela, Arnaldo Vilaxa, Viviana Durán, Isolde Rudolph, Nicolas Hrepic, and Gloria Calaf, “A Rat Mammary Tumor Model Induced by the Organophosphorous Pesticides Parathion and Malathion, Possibly through Acetylcholinesterase Inhibition,” Environmental Health Perspectives, 2001, 109:5.
ABSTRACT:
Environmental chemicals may be involved in the etiology of breast cancers. Many studies have addressed the association between cancer in humans and agricultural pesticide exposure. Organophosphorous pesticides have been used extensively to control mosquito plagues. Parathion and malathion are organophosphorous pesticides extensively used to control a wide range of sucking and chewing pests of field crops, fruits, and vegetables. They have many structural similarities with naturally occurring compounds, and their primary target of action in insects is the nervous system; they inhibit the release of the enzyme acetylcholinesterase at the synaptic junction. Eserine, parathion, and malathion are cholinesterase inhibitors responsible for the hydrolysis of body choline esters, including acetylcholine at cholinergic synapses. Atropine, a parasympatholytic alkaloid, is used as an antidote to acetylcholinesterase inhibitors. The aim of this study was to examine whether pesticides were able to induce malignant transformation of the rat mammary gland and to determine whether alterations induced by these substances increase the cholinergic activation influencing such transformation. These results showed that eserine, parathion, and malathion increased cell proliferation of terminal end buds of the 44-day-old mammary gland of rats, followed by formation of 8.6, 14.3, and 24.3% of mammary carcinomas, respectively, after about 28 months. At the same time, acetylcholinesterase activity decreased in the serum of these animals from 9.78 +/- 0.78 U/mL in the control animals to 3.05 +/- 0.06 U/mL; 2.57 +/- 0.15 U/mL; and 3.88 +/- 0.44 U/mL in the eserine-, parathion-, and malathion-treated groups, respectively. However, atropine alone induced a significant (p < 0.05) decrease in the acetylcholinesterase activity from the control value of 9.78 +/- 0.78 to 4.38 +/- 0.10 for atropine alone, to 1.32 +/- 0.06 for atropine in combination with eserine, and 2.39 +/- 0.29 for atropine with malathion, and there was no mammary tumor formation. These results indicate that organophosphorous pesticides induce changes in the epithelium of mammary gland influencing the process of carcinogenesis, and such alterations occur at the level of nervous system by increasing the cholinergic stimulation. FULL TEXT
Duke, 2015
Stephen O Duke, “Perspectives on transgenic, herbicide‐resistant crops in the United States almost 20 years after introduction,” Pest Management Science, 2015, 71:5, DOI: 10.1002/ps.3863.
ABSTRACT:
Herbicide-resistant crops have had profound impacts on weed management. Most of the impact has been by glyphosate-resistant maize, cotton, soybean, and canola. Significant economic savings, yield increases, and more efficacious and simplified weed management resulted in widespread adoption of the technology. Initially, glyphosate-resistant crops enabled significantly reduced tillage and reduced the environmental impact of weed management. Continuous use of glyphosate with glyphosate-resistant crops over broad areas facilitated the evolution of glyphosate-resistant weeds, which have resulted in increases in the use of tillage and other herbicides with glyphosate, reducing some of the initial environmental benefits of glyphosate-resistant crops. Transgenic crops with resistance to auxinic herbicides, as well as to herbicides that inhibit acetolactate synthase, acetyl-CoA carboxylase, and hydroxyphenylpyruvate dioxygenase, stacked with glyphosate and/or glufosinate resistance, will become available in the next few years. These technologies will provide additional weed management options for farmers, but will not have all of the positive impacts (reduced cost, simplified weed management, lowered environmental impact, and reduced tillage) that glyphosate-resistant crops had initially. In the more distant future, other herbicide-resistant crops (including non-transgenic ones), herbicides with new modes of action, and technologies that are currently in their infancy (e.g., bioherbicides, sprayable herbicidal RNAi, and/or robotic weeding) may impact the role of transgenic, herbicide-resistant crops in weed management.
Loomis et al., 2015
Dana Loomis, Kathryn Guyton, Yann Grosse, Fatiha El Ghissassi, Véronique Bouvard, Lamia Benbrahim-Tallaa, Neela Guha, Heidi Mattock, Kurt Straif, “Carcinogenicity of lindane, DDT, and 2,4-dichlorophenoxyacetic acid,” The Lancet, 2015, 16, DOI: 10.1016/S1470-2045(15)00081-9.
SUMMARY:
Summarizes the findings of 26 experts from 13 countries who met at the International Agency for Research on Cancer (IARC; Lyon, France) to assess the carcinogenicity of the insecticides lindane and 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT), and the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) for IARC Monographs Volume 113. 2,4-D was classified as “possibly carcinogenic to humans” (Group 2B) after some studies showed links to cancers including non-Hodgkin’s lymphoma. FULL TEXT
Bouchard et al., 2011
Bouchard MF, Chevrier J, Harley KG, Kogut K, Vedar M, Calderon N, Trujillo C, Johnson C, Bradman A, Barr DB, Eskenazi B., “Prenatal exposure to organophosphate pesticides and IQ in 7-year-old children.,” Environmental Health Perspectives, 2011, 119:8, DOI: 10.1289/ehp.1003185.
ABSTRACT:
CONTEXT: Organophosphate (OP) pesticides are neurotoxic at high doses. Few studies have examined whether chronic exposure at lower levels could adversely affect children’s cognitive development.
OBJECTIVE: We examined associations between prenatal and postnatal exposure to OP pesticides and cognitive abilities in school-age children.
METHODS: We conducted a birth cohort study (Center for the Health Assessment of Mothers and Children of Salinas study) among predominantly Latino farmworker families from an agricultural community in California. We assessed exposure to OP pesticides by measuring dialkyl phosphate (DAP) metabolites in urine collected during pregnancy and from children at 6 months and 1, 2, 3.5, and 5 years of age. We administered the Wechsler Intelligence Scale for Children, 4th edition, to 329 children 7 years of age. Analyses were adjusted for maternal education and intelligence, Home Observation for Measurement of the Environment score, and language of cognitive assessment.
RESULTS: Urinary DAP concentrations measured during the first and second half of pregnancy had similar relations to cognitive scores, so we used the average of concentrations measured during pregnancy in further analyses. Averaged maternal DAP concentrations were associated with poorer scores for Working Memory, Processing Speed, Verbal Comprehension, Perceptual Reasoning, and Full-Scale intelligence quotient (IQ). Children in the highest quintile of maternal DAP concentrations had an average deficit of 7.0 IQ points compared with those in the lowest quintile. However, children’s urinary DAP concentrations were not consistently associated with cognitive scores.
CONCLUSIONS: Prenatal but not postnatal urinary DAP concentrations were associated with poorer intellectual development in 7-year-old children. Maternal urinary DAP concentrations in the present study were higher but nonetheless within the range of levels measured in the general U.S. population. FULL TEXT
Koureas et al., 2012
Koureas M, Tsakalof A, Tsatsakis A, Hadjichristodoulou C., “Systematic review of biomonitoring studies to determine the association between exposure to organophosphorus and pyrethroid insecticides and human health outcomes,” Toxicology Letters, 2012, 210:2, DOI: 10.1016/j.toxlet.2011.10.007.
ABSTRACT:
For the appropriate protection of human health it is necessary to accurately estimate the health effects of human exposure to toxic compounds. In the present review, epidemiological studies on the health effects of human exposure to organophosphorus (OP) and pyrethroid (PYR) insecticides have been critically assessed. This review is focused on studies where the exposure assessment was based on quantification of specific biomarkers in urine or plasma. The 49 studies reviewed used different epidemiological approaches and analytical methods as well as different exposure assessment methodologies. With regard to OP pesticides, the studies reviewed suggested negative effects of prenatal exposure to these pesticides on neurodevelopment and male reproduction. Neurologic effects on adults, DNA damage and adverse birth outcomes were also associated with exposure to OP pesticides. With regard to exposure to PYR pesticides, there are currently few studies investigating the adverse health outcomes due to these pesticides. The effects studied in relation to PYR exposure were mainly male reproductive effects (sperm quality, sperm DNA damage and reproductive hormone disorders). Studies’ findings provided evidence to support the hypothesis that PYR exposure is adversely associated with effects on the male reproductive system. The validity of these epidemiological studies is strongly enhanced by exposure assessment based on biomarker quantification. However, for valid and reliable results and conclusions, attention should also be focused on the validity of the analytical methods used, study designs and the measured toxicants characteristics.
Mostafalou and Abdollahi, 2017
Sara Mostafalou and Mohammad Abdollahi, “Pesticides: an update of human exposure and toxicity,” Archives of Toxicology, February 2017, 91:2, DOI: 10.1007/s00204-016-1849-x.
ABSTRACT:
Pesticides are a family of compounds which have brought many benefits to mankind in the agricultural, industrial, and health areas, but their toxicities in both humans and animals have always been a concern. Regardless of acute poisonings which are common for some classes of pesticides like organophosphoruses, the association of chronic and sub-lethal exposure to pesticides with a prevalence of some persistent diseases is going to be a phenomenon to which global attention has been attracted. In this review, incidence of various malignant, neurodegenerative, respiratory, reproductive, developmental, and metabolic diseases in relation to different routes of human exposure to pesticides such as occupational, environmental, residential, parental, maternal, and paternal has been systematically criticized in different categories of pesticide toxicities like carcinogenicity, neurotoxicity, pulmonotoxicity, reproductive toxicity, developmental toxicity, and metabolic toxicity. A huge body of evidence exists on the possible role of pesticide exposures in the elevated incidence of human diseases such as cancers, Alzheimer, Parkinson, amyotrophic lateral sclerosis, asthma, bronchitis, infertility, birth defects, attention deficit hyperactivity disorder, autism, diabetes, and obesity. Most of the disorders are induced by insecticides and herbicides most notably organophosphorus, organochlorines, phenoxyacetic acids, and triazine compounds.
Islam et al., 2018
Faisal Islam, Jian Wang, Muhammad A. Farooq, Muhammad S.S. Khan, Ling Xu, Jinwen Zhu, Min Zhao, Stéphane Muños, Qing X. Li, Weijun Zhou, “Potential impact of the herbicide 2,4-dichlorophenoxyacetic acid on human and ecosystems,” Environment International, 2018, 111, DOI: 10.1016/j.envint.2017.10.020.
ABSRACT: The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is applied directly to aquatic and conventional farming systems to control weeds, and is among the most widely distributed pollutants in the environment. Non-target organisms are exposed to 2,4-D via several ways, which could produce toxic effects depending on the dose, frequency of exposure, and the host factors that influence susceptibility and sensitivity. An increasing number of experimental evidences have shown concerns about its presence/detection in the environment, because several investigations have pointed out its potential lethal effects on non-target organisms. In this review, we critically evaluated the environmental fate and behavior of 2,4-D along with its eco-toxicological effects on aquatic, plants and human life to provide concise assessment in the light of recently published reports. The findings demonstrate that 2,4-D is present in a low concentration in surface water of regions where its usage is high. The highest concentrations of 2,4-D were detected in soil, air and surface water surrounded by crop fields, which suggest that mitigation strategies must be implanted locally to prevent the entry of 2,4-D into the environment. A general public may have frequent exposure to 2,4-D due to its wide applications at home lawns and public parks, etc. Various in vivo and in vitro investigations suggest that several species (or their organs) at different trophic levels are extremely sensitive to the 2,4-D exposure, which may explain variation in outcomes of reported investigations. However, implications for the prenatal exposure to 2,4-D remain unknown because 2,4-D-induced toxicity thresholds in organism have only been derived from juveniles or adults. In near future, introduction of 2,4-D resistant crops will increase its use in agriculture, which may cause relatively high and potentially unsafe residue levels in the environment. The recent findings indicate the urgent need to further explore fate, accumulation and its continuous low level exposure impacts on the environment to generate reliable database which is key in drafting new regulation and policies to protect the population from further exposure.