Pardo et al., 2020
Pardo, L. A., Beane Freeman, L. E., Lerro, C. C., Andreotti, G., Hofmann, J. N., Parks, C. G., Sandler, D. P., Lubin, J. H., Blair, A., & Koutros, S.; “Pesticide exposure and risk of aggressive prostate cancer among private pesticide applicators;” Environmental Health, 2020, 19(1), 30; DOI: 10.1186/s12940-020-00583-0. https://www.ncbi.nlm.nih.gov/pubmed/32138787.
ABSTRACT:
BACKGROUND: Prostate cancer (PCa) is one of the most commonly diagnosed cancers among men in developed countries; however, little is known about modifiable risk factors. Some studies have implicated organochlorine and organophosphate insecticides as risk factors (particularly the organodithioate class) and risk of clinically significant PCa subtypes. However, few studies have evaluated other pesticides. We used data from the Agricultural Health Study, a large prospective cohort of pesticide applicators in North Carolina and Iowa, to extend our previous work and evaluate 39 additional pesticides and aggressive PCa.
METHODS: We used Cox proportional hazards models, with age as the time scale, to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between ever use of individual pesticides and 883 cases of aggressive PCa (distant stage, poorly differentiated grade, Gleason score >/= 7, or fatal prostate cancer) diagnosed between 1993 and 2015. All models adjusted for birth year, state, family history of PCa, race, and smoking status. We conducted exposure-response analyses for pesticides with reported lifetime years of use.
RESULTS: There was an increased aggressive PCa risk among ever users of the organodithioate insecticide dimethoate (n = 54 exposed cases, HR = 1.37, 95% CI = 1.04, 1.80) compared to never users. We observed an inverse association between aggressive PCa and the herbicide triclopyr (n = 35 exposed cases, HR = 0.68, 95% CI = 0.48, 0.95), with the strongest inverse association for those reporting durations of use above the median (>/= 4 years; n = 13 exposed cases, HR=0.44, 95% CI=0.26, 0.77).
CONCLUSION: Few additional pesticides were associated with prostate cancer risk after evaluation of extended data from this large cohort of private pesticide applicators.
Lerro et al., 2020
Lerro, C. C., Andreotti, G., Wong, J. Y., Blair, A., Rothman, N., & Beane Freeman, L. E.; “2,4-D exposure and urinary markers of oxidative DNA damage and lipid peroxidation: a longitudinal study;” Occupational and Environmental Medicine, 2020, 77(4), 276-280; DOI: 10.1136/oemed-2019-106267.
ABSTRACT:
OBJECTIVE: 2,4-Dichlorophenoxyacetic acid (2,4-D) is a herbicide that is commonly used commercially, agriculturally and residentially worldwide. There is concern about its potential for carcinogenicity based on studies in laboratory animals demonstrating the potential for induction of oxidative stress. We conducted a longitudinal biomarker study of 31 pesticide applicators in Kansas who heavily applied 2,4-D and 34 non-applicator controls.
METHODS: We used multivariable generalised linear mixed-effect models to evaluate the association between urinary 2,4-D and natural log-transformed 8-iso prostaglandin F2alpha (8-isoprostane) and 8-hydroxy-2′-deoxyguanosine (8-OHdG), adjusting for urinary creatinine, age, tobacco use and concomitant use of the herbicide picloram.
RESULTS: Compared with non-applicator controls, urinary 2,4-D in the third quartile of exposure was associated with elevated 8-isoprostane (e (beta)=1.38, 95% CI 1.03 to 1.84). There was no association among the highest exposed and no exposure-response trend. 2,4-D exposure was not associated with 8-OHdG. Results were unchanged when restricted to participants who only applied 2,4-D (no picloram use).
CONCLUSIONS: We did not find evidence that increasing 2,4-D exposure was associated with 8-isoprostane or 8-OHdG. Future work should carefully evaluate potential confounders of this association, such as diet and physical activity, as well as additional biological markers of oxidative stress and damage. FULL TEXT
Lerro et al., 2020
Lerro, C. C., Hofmann, J. N., Andreotti, G., Koutros, S., Parks, C. G., Blair, A., Albert, P. S., Lubin, J. H., Sandler, D. P., & Beane Freeman, L. E.; “Dicamba use and cancer incidence in the agricultural health study: an updated analysis;” International Journal of Epidemiology, 2020; DOI: 10.1093/ije/dyaa066.
ABSTRACT:
BACKGROUND: The herbicide dicamba has been commonly used agriculturally and residentially. Recent approval of genetically engineered dicamba-resistant crops is expected to lead to increased dicamba use, and there has been growing interest in potential human health effects. A prior analysis in the Agricultural Health Study (AHS) suggested associations between dicamba and colon and lung cancer. We re-evaluated dicamba use in the AHS, including an additional 12 years and 2702 exposed cancers.
METHODS: The AHS is a prospective cohort of pesticide applicators in Iowa and North Carolina. At enrollment (1993–1997) and follow-up (1999–2005), participants reported dicamba use. Exposure was characterized by cumulative intensity-weighted lifetime days, including exposure lags of up to 20 years. We estimated relative risks (RR) and 95% confidence intervals (CI) using multivariable Poisson regression for incident cancers diagnosed from enrollment through 2014/2015.
RESULTS: Among 49 922 applicators, 26 412 (52.9%) used dicamba. Compared with applicators reporting no dicamba use, those in the highest quartile of exposure had elevated risk of liver and intrahepatic bile duct cancer (nexposed = 28, RRQ4 = 1.80, CI: 1.26–2.56, Ptrend < 0.001) and chronic lymphocytic leukaemia (CLL, nexposed = 93, RRQ4 = 1.20, CI: 0.96–1.50, Ptrend = 0.01) and decreased risk of myeloid leukaemia (nexposed = 55, RRQ4 = 0.73, CI: 0.51–1.03, Ptrend = 0.01). The associations for liver cancer and myeloid leukaemia remained after lagging exposure of up to 20 years.
CONCLUSIONS: With additional follow-up and exposure information, associations with lung and colon cancer were no longer apparent. In this first evaluation of liver and intrahepatic bile duct cancer, there was an association with increasing use of dicamba that persisted across lags of up to 20 years. FULL TEXT
Gray et al., 2000
Gray, George M., Goldstein, Bernard D., Bailar, John, Davis, Devra Lee, Delzell, Elizabeth, Dost, Frank, Greenberg, Raymond S., Hatch, Maureen, Hodgson, Ernest, Ibrahim, Michel A., Lamb, James, Lavy, Terry, Mandel, Jack, Monson, Richard, Robson, Mark, Shore, Roy, & Graham, John D.; “The Federal Government’s Agricultural Health Study: A Critical Review with Suggested Improvements;” Human and Ecological Risk Assessment: An International Journal, 2000, 6(1), 47-71; DOI: 10.1080/10807030091124446.
ABSTRACT:
The Agricultural Health Study (AHS) has approximately 90,000 pesticide applicators and their spouses enrolled in a number of studies to determine whether exposures to specific pesticides are associated with various cancers and other adverse health outcomes. Although the AHS was intended to be an integrated program of studies, some significant difficulties have emerged. In this report, we examine the design of the AHS, identify important program strengths and flaws, suggest various improvements in the program, and recommend ancillary studies that could be undertaken to strengthen the AHS.
Overall, the AHS is collecting a large amount of information on potential determinants of health status among farmers and farm families. A promising feature of the AHS is the prospective cohort study of cancers among farmers in which the research design determines exposures prior to the diagnosis of disease. More effort needs to be devoted to reducing selection bias and information bias. Success of the cohort study will depend in part on follow-up surveys of the cohort to determine how exposures and disease states change as the cohort ages. The cross-sectional and case-control studies planned in the AHS are less promising because they will be subject to some of the same criticisms, such as potentially biased and imprecise exposure assessment, that have characterized the existing literature in this field.
Important limitations of the AHS include low and variable rates of subject response to administered surveys, concerns about the validity of some self-reported non-cancer health outcomes, limited understanding of the reliability and validity of self-reporting of chemical use, an insufficient program of biological monitoring to validate the exposure surrogates employed in the AHS questionnaires, possible confounding by unmeasured, nonchemical risk factors for disease, and the absence of detailed plans for data analysis and interpretation that include explicit, a priori hypotheses. Although the AHS is already well underway, most of these limitations can be addressed by the investigators if adequate resources are made available. If these limitations are not addressed, the large amounts of data generated in the AHS will be difficult to interpret. If the exposure and health data can be validated, the scientific value of the AHS should be substantial and enduring.
A variety of research recommendations are made to strengthen the AHS. They include reliability and validity studies of farmer reporting of chemical use, biological monitoring studies of farmers and members of farm families, and validity studies of positive and negative self-reports of disease status. Both industry and government should consider expanded research programs to strengthen the AHS.
Chiu, 2017
Chiu, Y. H.,”Pesticide Residues in Fruits and Vegetables: Assessment and Their Associations With Reproductive Health Outcomes;” Dissertation at Harvard Universiry, (Doctor of Science in Nutrition and Epidemiology); 2017.
ABSTRACT:
According to the Dietary Guideline, consumption of fruits and vegetables (FVs) are recommended throughout the lifespan, including during pregnancy. FVs, on the other hand, can serve as a vehicle of exposure to pesticide residues. In the US, Environmental Protection Agency (EPA) is responsible for regulating pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act and the Food Quality Protection Act. While majority of the produce sampled through the US Department of Agriculture had residues below the EPA limits, there is a growing concern whether chronic exposure to these pesticide residues may have adverse health effects, especially among susceptible populations such as pregnant women. Yet, such research is scarce. This dissertation focuses on the assessment of pesticide residues in FVs and evaluates their associations with pregnancy outcomes.
We previously have developed the Pesticide Residue Burden Score (PRBS) based on selfreported diet and national surveillance data on food pesticide residues to characterize dietary exposure over the past year. In Chapter 1, we evaluated the association of the PRBS with urinary pesticide metabolites in the Environment and Reproductive Health (EARTH) Study. We found intake of high pesticide residues FVs was positively associated with urinary concentrations of pesticide biomarkers, suggesting that PRBS can characterize dietary exposure to select pesticides.
In Chapter 2, we assessed the relation between preconception intake of high and low FVs and assisted reproductive technology outcomes in EARTH study. We found that intake of high pesticide residues FVs was associated with lower probability of clinical pregnancy and live birth, while intake of low pesticide residue FVs had the opposite relations among women undergoing infertility treatment. This is the first report of such relation in humans.
In Chapter 3, we examine the association between maternal intake of high and low pesticide residue FVs with birth outcomes in a pre-birth cohort. We found that maternal intake of high pesticide residue FVs during the first trimester was associated with higher risks of small-for-gestational-age among white women, while these exposures was associated with large-for-gestational-age among nonwhite women.
In conclusion, this work demonstrated the usefulness of PRBS in assessing pesticide residue intake through FVs. Using this method, these studies suggest exposure to pesticide residues may adversely affect pregnancy and birth outcomes.
Chiu et al., 2015
Chiu, Y. H., Afeiche, M. C., Gaskins, a. J., Williams, P. L., Petrozza, J. C., Tanrikut, C., Hauser, R., & Chavarro, J. E.; “Fruit and vegetable intake and their pesticide residues in relation to semen quality among men from a fertility clinic;” Human Reproduction, 2015, 0, 1-10; DOI: 10.1093/humrep/dev064.
ABSTRACT:
STUDY QUESTION: Is consumption of fruits and vegetables with high levels of pesticide residues associated with lower semen quality?
Summary Answer: Consumption of fruits and vegetables with high levels of pesticide residues was associated with a lower total sperm count and a lower percentage of morphologically normal sperm among men presenting to a fertility clinic.
WHAT IS KNOWN ALREADY: Occupational and environmental exposure to pesticides is associated with lower semen quality. Whether the same is true for exposure through diet is unknown.
STUDY DESIGN, SIZE, DURATION: Men enrolled in the Environment and Reproductive Health (EARTH) Study, an ongoing prospective cohort at an academic medical fertility center. Male partners (n = 155) in subfertile couples provided 338 semen samples during 2007–2012.
PARTICIPANTS/MATERIALS, SETTING, METHODS: Semen samples were collected over an 18-month period following diet assessment. Sperm concentration and motility were evaluated by computer-aided semen analysis (CASA). Fruits and vegetables were categorized as containing high or low-to-moderate pesticide residues based on data from the annual United States Department of Agriculture Pesticide Data Program. Linear mixed models were used to analyze the association of fruit and vegetable intake with sperm parameters accounting for within-person correlations across repeat samples while adjusting for potential confounders.
MAIN RESULTS AND ROLE OF CHANCE: Total fruit and vegetable intake was unrelated to semen quality parameters. High pesticide residue fruit and vegetable intake, however, was associated with poorer semen quality. On average, men in highest quartile of high pesticide residue fruit and vegetable intake (≥1.5 servings/day) had 49% (95% confidence interval (CI): 31%, 63%) lower total sperm count and 32% (95% CI: 7%, 58%) lower percentage of morphologically normal sperm than men in the lowest quartile of intake (,0.5 servings/day) (P, trend ¼ 0.003 and 0.02, respectively). Low-to-moderate pesticide residue fruit and vegetable intake was associated with a higher percentage of morphologically normal sperm (P, trend ¼ 0.04).
LIMITATIONS, REASONS FOR CAUTION: Surveillance data, rather than individual pesticide assessment,was used to assess the pesticide residue status of fruits and vegetables. CASA is a useful method for clinical evaluation but may be considered less favorable for accurate semen analysis in the research setting. Owing to the observational nature of the study, confirmation is required by interventional studies as well.
WIDER IMPLICATIONS OF THE FINDINGS: To our knowledge, this is the first report on the consumption of fruits and vegetables with high levels of pesticide residue in relation to semen quality. Further confirmation of these findings is warranted.
Curl et al., 2015
Curl, C. L., Beresford, S. A., Fenske, R. A., Fitzpatrick, A. L., Lu, C., Nettleton, J. A., & Kaufman, J. D.; “Estimating pesticide exposure from dietary intake and organic food choices: the Multi-Ethnic Study of Atherosclerosis (MESA);” Environmental Health Perspectives, 2015, 123(5), 475-483; DOI: 10.1289/ehp.1408197.
ABSTRACT:
BACKGROUND: Organophosphate pesticide (OP) exposure to the U.S. population is dominated by dietary intake. The magnitude of exposure from diet depends partly on personal decisions such as which foods to eat and whether to choose organic food. Most studies of OP exposure rely on urinary biomarkers, which are limited by short half-lives and often lack specificity to parent compounds. A reliable means of estimating long-term dietary exposure to individual OPs is needed to assess the potential relationship with adverse health effects.
OBJECTIVES: We assessed long-term dietary exposure to 14 OPs among 4,466 participants in the Multi-Ethnic Study of Atherosclerosis, and examined the influence of organic produce consumption on this exposure.
METHODS: Individual-level exposure was estimated by combining information on typical intake of specific food items with average OP residue levels on those items. In an analysis restricted to a subset of participants who reported rarely or never eating organic produce (“conventional consumers”), we assessed urinary dialkylphosphate (DAP) levels across tertiles of estimated exposure (n = 480). In a second analysis, we compared DAP levels across subgroups with differing self-reported organic produce consumption habits (n = 240).
RESULTS: Among conventional consumers, increasing tertile of estimated dietary OP exposure was associated with higher DAP concentrations (p < 0.05). DAP concentrations were also significantly lower in groups reporting more frequent consumption of organic produce (p < 0.02).
CONCLUSIONS: Long-term dietary exposure to OPs was estimated from dietary intake data, and estimates were consistent with DAP measurements. More frequent consumption of organic produce was associated with lower DAPs.
Parron et al, 2011
Parron, T., Requena, M., Hernandez, A. F., & Alarcon, R.; “Association between environmental exposure to pesticides and neurodegenerative diseases;” Toxicology and Applied Pharmacology, 2011, 256(3), 379-385; DOI: 10.1016/j.taap.2011.05.006.
ABSTRACT:
Preliminary studies have shown associations between chronic pesticide exposure in occupational settings and neurological disorders. However, data on the effects of long-term non-occupational exposures are too sparse to allow any conclusions. This study examines the influence of environmental pesticide exposure on a number of neuropsychiatric conditions and discusses their underlying pathologic mechanisms. An ecological study was conducted using averaged prevalence rates of Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, cerebral degeneration, polyneuropathies, affective psychosis and suicide attempts in selected Andalusian health districts categorized into areas of high and low environmental pesticide exposure based on the number of hectares devoted to intensive agriculture and pesticide sales per capita. A total of 17,429 cases were collected from computerized hospital records (minimum dataset) between 1998 and 2005. Prevalence rates and the risk of having Alzheimer’s disease, Parkinson’s disease, multiple sclerosis and suicide were significantly higher in districts with greater pesticide use as compared to those with lower pesticide use. The multivariate analyses showed that the population living in areas with high pesticide use had an increased risk for Alzheimer’s disease and suicide attempts and that males living in these areas had increased risks for polyneuropathies, affective disorders and suicide attempts. In conclusion, this study supports and extends previous findings and provides an indication that environmental exposure to pesticides may affect the human health by increasing the incidence of certain neurological disorders at the level of the general population. FULL TEXT
Hernandez et al, 2013
Hernandez, A. F., Parron, T., Tsatsakis, A. M., Requena, M., Alarcon, R., & Lopez-Guarnido, O.; “Toxic effects of pesticide mixtures at a molecular level: their relevance to human health;” Toxicology, 2013, 307, 136-145; DOI: 10.1016/j.tox.2012.06.009.
ABSTRACT:
Pesticides almost always occur in mixtures with other ones. The toxicological effects of low-dose pesticide mixtures on the human health are largely unknown, although there are growing concerns about their safety. The combined toxicological effects of two or more components of a pesticide mixture can take one of three forms: independent, dose addition or interaction. Not all mixtures of pesticides with similar chemical structures produce additive effects; thus, if they act on multiple sites their mixtures may produce different toxic effects. The additive approach also fails when evaluating mixtures that involve a secondary chemical that changes the toxicokinetics of the pesticide as a result of its increased activation or decreased detoxification, which is followed by an enhanced or reduced toxicity, respectively. This review addresses a number of toxicological interactions of pesticide mixtures at a molecular level. Examples of such interactions include the postulated mechanisms for the potentiation of pyrethroid, carbaryl and triazine herbicides toxicity by organophosphates; how the toxicity of some organophosphates can be potentiated by other organophosphates or by previous exposure to organochlorines; the synergism between pyrethroid and carbamate compounds and the antagonism between triazine herbicides and prochloraz. Particular interactions are also addressed, such as those of pesticides acting as endocrine disruptors, the cumulative toxicity of organophosphates and organochlorines resulting in estrogenic effects and the promotion of organophosphate-induced delayed polyneuropathy. FULL TEXT
Hernandez et al., 2006
Hernandez, A. F., Amparo Gomez, M., Perez, V., Garcia-Lario, J. V., Pena, G., Gil, F., Lopez, O., Rodrigo, L., Pino, G., & Pla, A.; “Influence of exposure to pesticides on serum components and enzyme activities of cytotoxicity among intensive agriculture farmers;” Environmental Research, 2006, 102(1), 70-76; DOI: 10.1016/j.envres.2006.03.002.
ABSTRACT:
Although the effects of acute pesticide poisoning are well known for the pesticides most currently used, hardly any data exist on health effects after long-term low-dose exposures. Major unresolved issues include the effect of moderate exposure in the absence of poisoning. The increased utilization of pesticides other than organophosphates makes it even more difficult to find associations. In this study a cohort of 106 intensive agriculture workers were assessed twice during the course of a spraying season for changes in serum biochemistry, namely enzymes reflecting cytotoxicity (AST, ALT, LDH, CK, and amino-oxidase) and other biochemical parameters, such as markers of nephrotoxicity (urea, creatinine) and lipid profile (cholesterol and triglycerides). Several criteria for estimating pesticide exposure were used, the most important one being serum cholinesterase depression greater than 25% from baseline to peak exposure. Our results revealed an association of pesticide exposure with changes in AST (increased activity), LDH, and amino-oxidase (decreased activity) as well as with changes in serum creatinine and phosphorus (lower and higher levels, respectively). These results provide support for a very slight impairment of the liver function, but overall these findings are consistent with no clinically significant hepatotoxicity. Intriguingly, paraoxonase-1 R allele was found to be an independent predictor of higher rates of AST and lower rates of amino-oxidase, so that it may play a supporting role as an individual marker of susceptibility on pesticide-induced health effects. In conclusion, different biomarkers might be used to detect early biochemical effects of pesticides before adverse clinical health effects occur. FULL TEXT