Rhinitis associated with pesticide exposure among commercial pesticide applicators in the Agricultural Health Study

Respiratory and allergic outcomes among farmworkers exposed to pesticides in Costa Rica

AIM

We examined the association of exposure to a pesticide mixture with respiratory and allergic outcomes among farmworkers from Costa Rica.

METHODS

We conducted a cross-sectional study of 299 farmworkers between May and August 2016. We collected information on sociodemographic factors, pesticide use, and the presence of respiratory and allergic symptoms during the last 12 months via questionnaire. We calculated specific gravity-adjusted average concentrations of 15 pesticide biomarkers measured in urine samples collected during two visits (4-5 weeks apart). We fitted "traditional" Bayesian and Bayesian Weighted Quantile Sum (BWQS) regression models to assess the association of exposure to independent and summed pesticide mixture components with the outcomes of interest. We adjusted all models for age and smoking status.

RESULTS

In "traditional" Bayesian analyses, higher urinary concentrations of 2-isopropyl-4-methyl-6-hydroxypyrimidine (IMPY, metabolite of organophosphate insecticide diazinon) were associated with increased odds of a higher asthma symptom score [adjusted OR per two-fold increase in concentrations = 1.15; 95 % credible interval (CrI): 1.04, 1.27)], asthma symptoms or medication use (aOR = 1.37; 95 % CrI: 1.13, 1.67), and rhinitis (aOR = 1.34; 95 % CrI: 1.15, 1.56). Higher urinary concentrations of boscalid-5-hydroxy (metabolite of fungicide boscalid) were associated with increased odds of asthma symptoms or medication use (aOR = 1.24; 95 % CrI: 1.00, 1.55), whereas higher concentrations of 4-hydroxypyrimethanil (metabolite of the fungicide pyrimethanil) were associated with increased odds of eczema (aOR = 1.11; 95 % CrI: 0.99, 1.24). Several inverse associations of herbicide concentrations with respiratory and allergic outcomes were observed. In BWQS analyses, a positive association was found between exposure to the pesticide mixture and increased odds of rhinitis (aOR = 1.96; 95 % CrI: 1.14, 3.20), with IMPY being the largest contributor.

CONCLUSION

Our findings indicate that exposure to pesticides may have both independent and summed mixture effects on respiratory and allergic health among farmworkers.

Short occupational exposure to glyphosate and its biomonitoring via urinary levels of glyphosate and metabolite AMPA (Amino-MethylPhosphonic acid), in Italian vineyard workers

Glyphosate, an herbicide largely used in various contexts, can have adverse effects on human health. Although it is currently the most applied pesticide worldwide, few studies evaluated the extent of human exposure via biomonitoring. To expand such information, biological monitoring of exposure to glyphosate was conducted. The study has a before-and-after design to demonstrate the immediate impact of short-term interventions. Accordingly, the urine concentrations of glyphosate and its main biodegradation product (amino-methylphosphonic acid- AMPA) were measured before and the day after the single herbicide application in 17 male winegrowers. Urine samples were analyzed by high performance liquid chromatography coupled with a triple quadrupole mass spectrometer equipped with an electrospray ionization source. Glyphosate and AMPA were not detectable in pre-application urine samples (limit of quantification for glyphosate (LOQG) was 0.1 μg/L; limit of quantification for AMPA (LOQAMPA) was 0.5 μg/L). After application, glyphosate urinary levels were above LOQG in all workers. The median, min, and max values were 2.30, 0.51, and 47.2 μg/L, respectively. The same values were found for 50 %, 5 % and 95 % percentiles. After assigning numerical values, such as one half the LOQ, to each of the non-detects, the "z" of Wilcoxon matched-pairs signed-ranks test was -3.62 (p = 0.0003), suggesting the pre-application values being significantly lower than the post-application urinary glyphosate concentration. A similar analysis was not feasible with AMPA urinary levels, which were detectable only in 3 workers, after application. 12 (71 %) workers were significantly exposed to glyphosate, but adherence to the adoption of personal protective equipment was good: 14 (82 %) workers used gloves, 13 (76 %) used overalls and 13 (76 %) facial masks. Our data show that glyphosate can be absorbed by the workers after a single application and confirms the usefulness of biomonitoring in exposed workers. Further studies are needed in larger working populations and with multiple glyphosate applications, as well as to evaluate the correlations of glyphosate urine levels with exposure questionnaire data, in order to assess the actual relevance of risk and protection factors.

Association between early life exposure to agriculture, biodiversity, and green space and risk of inflammatory bowel disease: a population-based cohort study

Background

Specific pollutants and environmental exposures are implicated in modulating inflammatory bowel disease (IBD) risk. However, the role of environmental exposures, particularly during the early life period, towards IBD risk, has not been systematically evaluated.

Methods

We conducted a nationwide population-based cohort study during the study period extending from January 1, 1995, to September 1, 2020, using cross-linked Danish registers, maps, and inventories to ascertain the impact of agricultural land use, biodiversity, green space, urban space, blue space, and normalized difference vegetation index during pregnancy and the first two years of life on IBD, Crohn's disease (CD), and ulcerative colitis (UC) risk, using adjusted Cox proportional hazards regression analyses. We adjusted for covariates sex, maternal age at delivery, calendar year of birth, municipal-level socioeconomic status, and first-degree relative with IBD.

Findings

Of 1,438,487 individuals included in the study who were followed from age 2 years until a median (IQR) age of 14 (8-20) years, 3768 individuals were diagnosed with IBD. Exposure to the second, third and highest quartiles of agriculture land use during early life, relative to the lowest quartile, were associated with increased CD risk (aHR 1.12, 95% CI 1.01, 1.26, 1.19, 95% CI 1.05, 1.34 and, 1.24 95% CI 1.06, 1.46, respectively). There was no association of agriculture land use with UC risk. Conversely, exposure to the third quartile of biodiversity in early life, compared to the lowest quartile, were associated with a lower CD risk (aHR 0.86, 95% CI 0.75, 0.98). A protective effect of greenspace was noted in the highest quartile for CD (aHR 0.87, 95% CI 0.78, 0.98).

Interpretation

In a nationwide cohort with long-term follow up data, early life environmental exposures were associated with modulation of CD risk, with a harmful effect of agriculture land use and protective effect of biodiversity and green space.

Funding

Danish National Research Foundation, the International Organization for the Study of Inflammatory Bowel Disease, the National Institute of Diabetes and Digestive and Kidney Diseases.

Assessing the effectiveness of mitigating pesticide-related disease risk among pesticide-spraying drone operators in Taiwan

OBJECTIVES

The purpose of this study was to evaluate the risk of pesticide poisoning, liver and renal failure, dermatitis, respiratory problems, hypersensitivity pneumonitis, keratitis, and epilepsy among pesticide-spraying personnel and to assess the effectiveness of a new method of aerial pesticide application in reducing this risk.

METHODS

A total of 2268 pesticide spraying operators (1651 ground-based field crop operators and 617 aerial pesticide spraying drone operators) who passed the national certification examination between 2010 and 2020 in Taiwan were included. Ground-based operators served as the positive control group, while 2463 farmer controls were matched from the Farmers' Health Insurance database as the negative control group. Data from the National Health Insurance Research Database were used to track possible pesticide-related disease cases. Logistic regression was employed to calculate odds ratios and 95% confidence intervals (95% CI).

RESULTS

Drone operators had significantly reduced risks of dermatitis, asthma and chronic bronchitis compared to ground-based operators. This was observed in allergic contact dermatitis (OR = 0.40, 95% CI: 0.24-0.68), unspecified contact dermatitis (OR = 0.58, 95% CI: 0.35-0.97), asthma (OR = 0.27, 95% CI: 0.12-0.60), and chronic bronchitis (OR = 0.24, 95% CI: 0.06-0.93), after adjusting for age, sex, working areas, and licensing years. However, no significant differences were found when comparing drone operators to matching farmers.

CONCLUSIONS

Aerial pesticide spraying using drones may contribute to a decreased risk of dermatitis, asthma and chronic bronchitis, suggesting potential health benefits for operators. Further field pesticide exposure surveys are recommended to validate these findings and assess health risk indicators.

Pesticide exposure and rhinitis: A cross-sectional study among farmers in Pitsanulok, Thailand

Background

Pesticide exposure has been suspected as a cause of rhinitis, a common disease that affects the health and well-being of millions of people around the world. This cross-sectional study aimed to examine the association between pesticide use and rhinitis prevalence among farmers in Phitsanulok province, Thailand.

Methods

Data on historical pesticide use and rhinitis were collected by an in-person interview questionnaire. Data from 9,649 participants were included in the analysis. The association between pesticide exposure and rhinitis was determined by multiple variable logistic regression, adjusted for potential confounding factors.

Results

The study found an association between pesticide exposure and the prevalence of rhinitis. The association was consistent across various types of pesticides (insecticides, herbicides, fungicides, rodenticides, and molluscicides) and individual pesticides. Some of the relationships were in a dose-response pattern. This finding was new as previous studies often reported the association of only a few specific pesticides.

Conclusions

The results from this large cross-sectional study supports existing literature on the potential effects of pesticides on rhinitis. In addition, the analysis showed that the rhinitis effect might be in fact related to the properties of the types of pesticides rather than individual chemical toxicity. The impact of pesticides on rhinitis should receive more attention from public health and other organizations responsible for the farmers' health.

Residential Proximity to a Commercial Pesticide Application Site and Risk of Chronic Rhinosinusitis

Importance

Environmental and occupational toxicants have been shown to be associated with an increased prevalence of chronic rhinosinusitis (CRS). However, few to no studies have evaluated patients for CRS using objective testing and workup protocols that fulfill guidelines for CRS diagnostic criteria. Furthermore, no study, to our knowledge, has investigated the risks of CRS in the context of residential exposure through proximity to a commercial pesticide application site.

Objectives

To evaluate associations of residential proximity to a commercial pesticide application site and the prevalence of CRS with nasal polyps (CRSwNP) and without nasal polyps (CRSwoNP).

Design, Setting, and Participants

This was a retrospective cohort study of patients who presented to a tertiary care institution for rhinology evaluation between March 1, 2018, and December 31, 2022.

Main Outcomes and Measures

The outcome variable was the clinical diagnosis of CRS (CRSwNP, CRSwoNP, or non-CRS control). Patients' residential addresses were utilized to determine pesticide exposure status based on a validated computational geographic information algorithm based on data from the California Pesticide Use Report System. The dichotomous independent variable of exposure status (exposed or non-exposed) was determined by assessing reports of any pesticide applications within 2000 m of each participant's residence in 2017. Multivariable logistic regressions assessing CRS status and CRS subtypes were conducted with pesticide exposure as the primary covariate of interest. The primary study outcome and measurements as well as study hypothesis were all formulated before data collection.

Results

Among a total of 310 patients (90 CRSwNP, 90 CRSwoNP, and 130 control), the mean (SD) age was 50 (17) years; 164 (53%) were female. Race and ethnicity information was not considered. Controlling for patient demographic information, smoking history, county of residence, and medical comorbidities, pesticide exposure was associated with an approximately 2.5-fold increase in odds of CRS (adjusted odds ratio, 2.41; 95% CI, 1.49-3.90). Pesticide exposure was associated with similar risks for CRSwNP (adjusted relative risk ratio [aRRR], 2.34; 95% CI, 1.31-4.18) and CRSwoNP (aRRR, 2.42; 95% CI, 1.37-4.30).

Conclusions and Relevance

The findings of this retrospective cohort study and analysis revealed that residential exposure to commercial pesticide application within a 2000-m buffer was independently associated with an approximately 2.5-fold increase in odds of being diagnosed with CRS. If validated by additional research, this association would have substantial implications for public health.

Spatial cluster mapping and environmental modeling in pediatric inflammatory bowel disease

BACKGROUND

Geographical (geospatial) clusters have been observed in inflammatory bowel disease (IBD) incidence and linked to environmental determinants of disease, but pediatric spatial patterns in North America are unknown. We hypothesized that we would identify geospatial clusters in the pediatric IBD (PIBD) population of British Columbia (BC), Canada and associate incidence with ethnicity and environmental exposures.

AIM

To identify PIBD clusters and model how spatial patterns are associated with population ethnicity and environmental exposures.

METHODS

One thousand one hundred eighty-three patients were included from a BC Children’s Hospital clinical registry who met the criteria of diagnosis with IBD ≤ age 16.9 from 2001–2016 with a valid postal code on file. A spatial cluster detection routine was used to identify areas with similar incidence. An ecological analysis employed Poisson rate models of IBD, Crohn’s disease (CD), and ulcerative colitis (UC) cases as functions of areal population ethnicity, rurality, average family size and income, average population exposure to green space, air pollution, and vitamin-D weighted ultraviolet light from the Canadian Environmental Health Research Consortium, and pesticide applications.

RESULTS

Hot spots (high incidence) were identified in Metro Vancouver (IBD, CD, UC), southern Okanagan regions (IBD, CD), and Vancouver Island (CD). Cold spots (low incidence) were identified in Southeastern BC (IBD, CD, UC), Northern BC (IBD, CD), and on BC’s coast (UC). No high incidence hot spots were detected in the densest urban areas. Modeling results were represented as incidence rate ratios (IRR) with 95%CI. Novel risk factors for PIBD included fine particulate matter (PM_2.5) pollution (IRR = 1.294, CI = 1.113-1.507, P < 0.001) and agricultural application of petroleum oil to orchards and grapes (IRR = 1.135, CI = 1.007-1.270, P = 0.033). South Asian population (IRR = 1.020, CI = 1.011-1.028, P < 0.001) was a risk factor and Indigenous population (IRR = 0.956, CI = 0.941-0.971, P < 0.001), family size (IRR = 0.467, CI = 0.268-0.816, P = 0.007), and summer ultraviolet (IBD = 0.9993, CI = 0.9990–0.9996, P < 0.001) were protective factors as previously established. Novel risk factors for CD, as for PIBD, included: PM_2.5 air pollution (IRR = 1.230, CI = 1 .056-1.435, P = 0.008) and agricultural petroleum oil (IRR = 1.159, CI = 1.002-1.326, P = 0.038). Indigenous population (IRR = 0.923, CI = 0.895–0.951, P < 0.001), as previously established, was a protective factor. For UC, rural population (UC IRR = 0.990, CI = 0.983-0.996, P = 0.004) was a protective factor and South Asian population (IRR = 1.054, CI = 1.030–1.079, P < 0.001) a risk factor as previously established.

CONCLUSION

PIBD spatial clusters were identified and associated with known and novel environmental determinants. The identification of agricultural pesticides and PM_2.5 air pollution needs further study to validate these observations.

Adhesion Molecules in Lung Inflammation from Repeated Glyphosate Exposures

Glyphosate is an active ingredient in herbicides. Exposure to glyphosate-based herbicides has been associated with respiratory dysfunctions in agricultural workers. The ability of inhaled glyphosate to induce lung inflammation is not well understood. Further, the role of adhesion molecules in glyphosate-induced lung inflammation has not been studied. We evaluated lung inflammatory responses from single and repeated glyphosate exposures. Male C57BL/6 mice were intranasally exposed to glyphosate (1 μg/40 μL) for 1 day or once daily for 5 days or 10 days. Lung tissue and bronchoalveolar lavage (BAL) fluid were collected and analyzed. Repeated exposure to glyphosate for 5 days and 10 days resulted in an increase in neutrophils in BAL fluid and higher eosinophil peroxidase levels in lungs, with leukocyte infiltration further confirmed through lung histology. Repetitive exposure to glyphosate increased IL-33 and Th2 cytokines IL-5 and IL-13. A single glyphosate treatment revealed expression for ICAM-1, VCAM-1, and vWF adhesion molecules in the perivascular region of lung sections; with repeated treatment (5 and 10 days), adhesion molecule expression was found in the perivascular, peribronchiolar, and alveolar regions of the lungs. Repetitive exposure to glyphosate induced cellular inflammation in which adhesion molecules may be important to the lung inflammatory process.

Occupational factors affecting the decline in pulmonary function among male farmers using occupational pesticide in Gyeonggi-do, South Korea

Background

Occupational pesticide exposure is a potential risk for respiratory health effects. Most clinical studies on pesticide exposure were related to acute exposure, and only a few studies on chronic exposure have been conducted. This study investigated the chronic respiratory health status and the chronic effects of occupational pesticide exposures of farmers in Gyeonggi-do.

Methods

Surveys and pulmonary function tests were conducted on 1,697 farmers in 16 regions of Gyeonggi-do. The structured questionnaire included demographic characteristics, medical history, recent respiratory symptoms and diseases, and work-related conditions, and was conducted through one-on-one interviews. The prevalence of respiratory diseases was compared by the odds ratios (ORs) at 95% confidence intervals (CIs) estimated by logistic regression analysis. Additional multivariate logistic regression analysis was also conducted.

Results

Pesticide work groups showed significant association with an obstructive pattern in the lung function test (unadjusted OR, 2.38; 95% CI, 1.17-5.52). Selected work-related variables of pesticide exposure were 'start age,' 'cumulative duration,' 'mixing pesticides,' and 'protection(goggle).' The obstructive pattern of lung function test showed significant associations with mixing pesticides (OR, 2.30; 95% CI,1.07-5.46), and protection (goggle) use (OR, 0.34; 95% CI, 0.12-0.79).

Conclusions

Mixing two or more pesticides showed a significant association. Wearing goggles can be seen as an indicator of awareness of the protective equipment and proper wearing of protective equipment, and loss of pulmonary function can be prevented when appropriate protection is worn.

Direct Effects of Glyphosate on In Vitro T Helper Cell Differentiation and Cytokine Production

Glyphosate (G) is the active ingredient of the most used herbicides worldwide. Its use is currently very debated, as several studies indicating its hazard and toxicity are emerging. Among them, there is evidence of adverse effects on the immune system. The aim of this work was to investigate if G could directly affect immune cells. Peripheral blood mononuclear cells (PBMC) obtained from healthy donors were used as experimental model. PBMC were expose to G and stimulated with PMA/ionomycin, T helper (Th) cell differentiation and cytokine production were assessed by flow cytometry and enzyme-linked immunosorbent assay, respectively. A reduction of Th1/Th2 ratio, mainly due to a decrease in Th1 cells, was observed following G exposure. Results show an enhancement of IL-4 and IL-17A production, and a reduction of IFN-γ. Based on literature evidence that suggest G being an endocrine disruptor, we investigated the role of nuclear estrogen receptors (ER). ERα/ERβ inhibition by ICI 182,780 abolished the effects of G on IFN-γ and IL-4 release, suggesting a role of ER in the observed effects. To further characterize the mechanism of action of G, miRNAs, both in exosome and intracellular, were investigated. A statistically significant increase in miR-500a-5p was observed following G treatment. The blockage of miR-500a-5p, using a specific antagomir, prevented G-induced reduction of IFN-γ production. Finally a relationship between miR-500a-5p up-regulation and ER was observed. Overall, these results suggest that G can directly act on T cells, altering T cell differentiation and cytokines production.

Prevalence and Risk Factors for Pulmonary Conditions among Farmers and Ranchers in the Central United States

This study was conducted to evaluate the prevalence and risk factors for work-related respiratory conditions (asthma, farmer's lung, sinusitis, rhinitis, and environmental allergies, diagnosed by a physician) among farm and ranch operators in the central US. A survey was conducted by the Central States Center for Agricultural Safety and Health (CS-CASH) in 2018, focusing on work-related injuries, illnesses, exposures, and preventive measures in a seven-state region (Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, and South Dakota). Farms and ranches (n = 16,818) with an email address and annual sales exceeding $5,000 were randomly selected for the survey. Agricultural production and weather data were merged with survey responses. The relationship between exposures and respiratory conditions was analyzed using generalized estimating equations. We received responses from 3,268 agricultural operations (19% response rate) containing information on 4,064 individual operators. The life-time prevalence of (any) respiratory conditions among farm/ranch operators was 18%. Risk factors for respiratory conditions included exposures to grain/hay/feed dust (OR 2.41), animal confinement dust (OR 1.57), field/road dust (OR 2.11), manure/silage gasses (OR 1.66), anhydrous ammonia (OR 1.51), fuels/solvents/paints (OR 1.92), older age group >70 vs. <43 (OR 1.40), female gender (OR 1.82), and being primary vs. third operator (OR 1.61). Farmers and ranchers have a high prevalence of respiratory conditions associated with dust and gas exposures at work. More effective protective measures are needed using the hierarchy of controls, including improved use of respiratory protection.

Using the Matrix to bridge the epidemiology/risk assessment gap: a case study of 2,4-D

BACKGROUND

The Matrix is designed to facilitate discussions between practitioners of risk assessment and epidemiology and, in so doing, to enhance the utility of epidemiology research for public health decision-making. The Matrix is comprised of nine fundamental "asks" of epidemiology studies, focusing on the types of information valuable to the risk assessment process.

OBJECTIVE

A 2,4-dichlorophenoxyacetic acid (2,4-D) case study highlights the extent to which existing epidemiology literature includes information generally needed for risk assessments and proffers suggestions that would assist in bridging the epidemiology/risk assessment gap.

METHODS

Thirty-one publications identified in the US Environmental Protection Agency 2,4-D epidemiology review were assessed. These studies focused on associations between 2,4-D exposure and non-Hodgkin lymphoma (NHL), respiratory effects, and birth outcomes.

RESULTS

Many of the papers met one or more specific elements of the Matrix. However, from this case study, it is clear that some aspects of risk assessment, such as evaluating source-to-intake pathways, are generally not considered in epidemiology research. Others are incorporated, but infrequently (e.g. dose-response information, harmonization of exposure categories). We indicated where additional analyses or modifications to future study design could serve to improve the translation.

DISCUSSION

Interaction with risk assessors during the study design phase and using the Matrix "asks" to guide the conversations could shape research and provide the basis for requests for funds to support these additional activities. The use of the Matrix as a foundation for communication and education across disciplines could produce more impactful and consequential epidemiology research for robust risk assessments and decision-making.

Rhinoscleroma Masquerading as a Nasopharyngeal Malignancy

Klebsiella rhinoscleromatis, the causative agent of rhinoscleroma, is a Gram-negative, facultative intracellular, non-motile, encapsulated bacillus. The organism has a very low infectivity necessitating a chronic exposure for infection. Prevalence is also high in developing countries like India. The factors responsible for this are attributed to poor hygiene, poor access to medications and overcrowded living conditions.1 Though entire respiratory mucosa can be affected, the organism has an affinity for nasal mucosa and thus nasal cavity is the most prevalent site accounting for 95–100 % of cases. In decreasing order of involvement nasopharynx (18 – 43 %), larynx (15 – 40 %), trachea (12 %) and bronchi (2 – 7 %) are the other sites.2 Our patient had bilateral nasal obstruction and discharge since 6 months as the only presenting complaint. Clinically there was no evidence of lymphadenopathy, but the CT scans of the paranasal sinuses showed heterogeneously ill-defined mass in the posterior nasal cavity, raising suspicion of a malignancy. Hence the case was further investigated.

Pulmonary inflammatory response from co-exposure to LPS and glyphosate

Agricultural airborne work exposures are complex in nature and workplace exposures are a risk for respiratory outcomes in workers. Endotoxin and glyphosate are two common agents in agricultural exposures. While endotoxin (lipopolysaccaride, LPS) is a potent inflammatory agent it explains only a portion of the respiratory inflammatory response. The inflammatory potential when LPS is presented with another common agricultural respiratory agent, glyphosate, is not known.

METHODS

Mice were assigned to four treatment groups: control, LPS alone, glyphosate alone, glyphosate and LPS combined. Treatments were for 1, 5 or 10 days.

RESULTS

Five days of repeated exposure to the comintation of LPS and glyphosate resulted in higher neutrophil counts, myloperoxidase, TNF-α, IL-6, KC levels, and ICAM-1 and TLR-2 expression compared to the same length of treatment to LPS or glyphosate alone. After 10-days of exposure, inflammatory responses decreased, however leukocyte infiltration persisted along with increases in IL-4.

CONCLUSIONS

Glyphosate exposure modified LPS induced lung inflammatory responses and TLR-2 may be important in the modulated inflammatory response.

Glyphosate-based herbicides: Evidence of immune-endocrine alteration

Glyphosate (G) is the active ingredient of the most widely used herbicide products. It targets the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), which lacks in humans, suggesting to confer a low mammalian toxicity to G-based herbicides (GBHs). Despite this, the use of G is currently under intense debate. Many studies indicating its hazard and toxicity on non-target organisms are emerging, and associations between GBHs and immune-endocrine disturbances have been described. This review aims to investigate, based on recent epidemiological studies and studies performed in vitro and in vivo in animals, the possible association between GBHs and immune-endocrine alterations. Published data suggest that GBHs have endocrine disrupting potentiality targeting sex and thyroid hormones, although its relevance for humans will require further investigations. Evidence of immunotoxicity are limited compared to those on endocrine effects, but overall highlight possible noxious effects, including lung inflammation and rhinitis. An attractive hypothesis could be the one that connects microbiota dysbiosis with possible immune-endocrine outcomes. Indeed, several intestinal microorganisms express the enzyme EPSPS and, studies are emerging that highlight a possible G-induced dysbiosis. Considering the wide use of GBHs in agriculture, further studies investigating their noxious effects at levels relevant for human exposure should be performed. A critical analysis of emerging evidence of G toxicity is required to better characterize its safety profile. In addition, attention should be paid to the differences between G alone and its formulations, which, containing substances able to increase G absorption, may present a different toxicity profile.

Occupational health and safety in agriculture. A systematic review

Introduction: The prevalence of occupational diseases in the agricultural sector is higher than in other industries, since agricultural workers are at higher risk of exposure to different chemicals and pesticides, and are more prone to occupational accidents.Objective: To conduct a review of recent literature on occupational health and risk in agriculture.Materials and methods: A literature search was conducted in PubMed, SciencieDirect and Scopus using the following search strategy: type of articles: original research papers; language: English; publication period: 2006-2016; search terms: "agricultural health", "agrarian health", "risk factors", "epidemiology", "causality" and "occupational", used in different combinations ("AND" and "OR").Results: The search yielded 350 articles, of which 102 met the inclusion criteria. Moreover, 5 articles were found in grey literature sources and included in the final analysis. Most research on this topic has been conducted in the United States, which produced 91% (97/107) of the articles included.Conclusions: Most studies on health and safety in agriculture focused primarily on the harmful effects of occupational exposure to agrochemicals and pesticides, and the consequences of occupational accidents. However, since more than 90% of these studies come from the United States, a more comprehensive approach to health in agriculture is required, since what is reported here may be far from the reality of other regions, especially Latin America.

Association between use of humidifier disinfectant and allergic rhinitis in Korean children: a cross-sectional study based on the eighth Panel Study on Korean Children (PSKC)

Background

Rhinitis was the most frequently diagnosed disorder among users of humidifier disinfectants (HDs). The aim of our study was to investigate on the relationship between allergic rhinitis (AR) and HD uses.

Methods

Our study used the data from the eighth Panel Study on Korean Children; a total of 1,540 participants were enrolled. The χ² test and multiple logistic regression analyses were conducted to debunk the association between AR and HD uses.

Results

In our analysis, odds ratios (ORs) of doctor-diagnosed AR increased significantly when simply the response of whether HDs were used in the past was considered. When the brands of HD were considered, ORs of doctor-diagnosed AR were found to be increased significantly for those who have used polyhexamethylene guanidine phosphate/oligo(2-[2-ethoxy]-ethoxyethyl)guanidinium-containing HDs (model 3: 1.41, 95% confidence interval [CI]: 1.02-1.95). However, once duration of usage was additionally considered, ORs of doctor-diagnosed AR increased significantly only for those who have used chloromethylisothiazolinone/methylisothiazolinone-containing HDs for more than or equal to 3 months (model 3: 2.08, 95% CI: 1.17-3.69). Further, past use of HD was associated with significantly increased ORs of AR diagnosed before 2013 (model 3: 1.35, 95% CI: 1.02-1.79).

Conclusions

Results of our study suggest that past uses of HDs may be associated with an increased risk of AR.

Effects of glyphosate exposure on human health: Insights from epidemiological and in vitro studies

Glyphosate (GLY) is a broad-spectrum, post-emergent, non-selective and synthetic universal herbicide, whose commercial formulations are referred to as glyphosate-based-herbicides (GBHs). These chemicals and their metabolites can be found in soil, air, water, as well as groundwater and food products. This review summarizes to summarize current in vitro and epidemiological studies investigating the effects of GLY exposure on human health. Recent human cell studies have reported several GLY and GBH toxicological effects and have contributed to a better understanding of the deleterious consequences associated with their exposure. However, these detrimental effects are dependent on the cell type, chemical composition, as well as magnitude and time of exposure, among other factors. Moreover, the deleterious effects of GLY exposure on human health were observed in epidemiological studies; however, most of these studies have not determined the GLY dosage to confirm a direct effect. While GLY toxicity is clear in human cells, epidemiological studies investigating individuals exposed to different levels of GLY have reported contradictory data. Therefore, based on currently available in vitro and epidemiological data, it is not possible to confirm the complete safety of GLY use, which will require additional comprehensive studies in animal models and humans.

Variability and predictors of weekly pesticide exposure in applicators from organic, sustainable and conventional smallholder farms in Costa Rica

Objective

Estimates of pesticide exposure among applicators from low- and middle-income countries (LMICs) are scarce, and exposure assessment methods are sometimes costly or logistically unfeasible. We examined the variability in weeklong pesticide exposure among applicators in Costa Rica and its predictors.

Methods

We conducted a cross-sectional survey among 221 pesticide applicators from organic, sustainable and conventional farms in 2016. We administered structured questionnaires to assess pesticide application practices at two time points (4–6 weeks apart). We adapted an existing algorithm to fit the context of smallholders and derive weekly pesticide exposure scores. We used linear mixed-effect models to examine within-worker and between-worker score variability. We then identified sociodemographic and occupational predictors of weekly pesticide exposure scores.

Results

We observed high within-worker and between-worker variability in weekly pesticide exposures (eg, up to 180-fold and 70-fold differences in average weekly exposures within and between workers, respectively; intraclass correlation coefficient=0.4). Applicators working on conventional and sustainable farms had exposure scores twofold and 1.5-fold higher than those working in organic farms, respectively. Farm workers who received training on pesticide use had weekly pesticide exposure scores of 33% (95% CI 1% to 55%) lower than those who did not receive any training.

Conclusions

In this study of applicators from smallholder farms in Costa Rica, we determined the importance of collecting questionnaire data on self-reported pesticide use repeatedly due to its high variability within workers and absence of application records. Our questionnaire-based exposure algorithm could allow the calculation of semiquantitative estimates of average pesticide exposure for applicators from other LMICs.

Pesticide use, allergic rhinitis, and asthma among US farm operators

OBJECTIVE

The objective of the study is to examine associations between use of specific pesticides and lifetime allergic rhinitis and current asthma in US primary farm operators.

METHODS

The 2011 Farm and Ranch Safety Survey data from 11,210 primary farm operators were analyzed. Pesticide use on the farm was determined using an affirmative response to the question of whether the operator ever mixed, loaded, or applied pesticides on their farm in the 12 months prior to the interview. Operators who answered "yes" were further asked about the specific trade name and formulation identifiers of the product they used and personal protective equipment (PPE) used. Data were weighted to produce national estimates. Adjusted prevalence odds ratios (PORs) were calculated using logistic regression. The referent group included operators who did not use any pesticides in the 12 months prior to the interview.

RESULTS

Of an estimated 2.1 million farm operators, 40.0% used pesticides, 30.8% had lifetime allergic rhinitis, and 5.1% had current asthma. Insecticide and herbicide use were significantly associated with lifetime allergic rhinitis and current asthma. The use of 2,4-dichlorophenoxyacetic acid (POR = 1.5; 95% CI 1.2-1.9) and carbaryl (POR = 2.3; 1.4-3.7) was significantly associated with lifetime allergic rhinitis. Of operators using pesticides, 64.9% used PPE the last time they mixed, loaded, or applied pesticides.

CONCLUSIONS

Pesticide use was associated with lifetime allergic rhinitis and current asthma among farm operators. Further studies are needed to clarify the dose-response relationship between pesticide use and adverse respiratory health effects.

Preparation of magnetic polyimide@ Mg-Fe layered double hydroxides core-shell composite for effective removal of various organic contaminants from aqueous solution

In this work, a novel core-shell structured magnetic polyimide@layered double oxides (LDO) composites coating a porous polyimide (PI)-coated Fe3O4 magnetic core and layered double hydroxide (LDH) has been successfully synthesized by solve-thermal synthesis and co-precipitation process. The magnetic PI@LDO composites were characterized by scanning and transmission electron microscopy (SEM and TEM), X-ray diffraction (XRD), thermogravimetry analysis (TGA) and magnetic properties analysis. The composite materials displayed core-shell structure with flower-like morphology. The magnetic PI@LDO composites were applied to remove tetracycline (TC), 2,4-dichlorophenol (2,4-DCP) and glyphosate (GP) from aqueous solution. The action pH value was ranged from 5 to 9 for TC and GP and 3 to 7 for 2,4-DCP, respectively. Cl- showed a weak competitive adsorption effect to TC, 2, 4-DCP and GP. In addition, the presence of humic acid (HA) could slightly reduce the adsorption capacity of magnetic PI@LDO composites. The adsorption process could be well described by pseudo-second-order model for TC and GP, while pseudo-first-order model for 2,4-DCP. The experimental data of TC and 2,4-DCP could be fitted better with Freundlich model, while that of GP were fitted better with Langmuir model. The adsorptions of TC, 2,4-DCP and GP were both spontaneous and endothermic. The adsorption capacity decreased slightly after adsorption-desorption cycles repeated five times. This study demonstrated that magnetic PI@LDO exhibited great potential to be a mild and cost-effective adsorbent for the removal of various organic contaminants from wastewater.

Pesticide and Human Health

Pesticides are known to be one of the extremely useful and incredibly beneficial agents for preventing losses of crops as well as diseases in humans. They are used in a large number of conditions as in farms, orchards, gardens, parks, sports lawn, residences, industrial areas, shops, schools, hospitals, airports, railway lines, drains, on animals, and on people for control of diseases such as scabies and head lice. People are exposed to pesticides in their daily lives through multiple routes of exposure such as occupational or food, water, and air. Many pesticides can be used safely and effectively, but care must be taken while using them. Several pesticides are beneficial in agriculture for killing pests. Yet many times their injurious effects offset the positive ones. Uses of pesticides are apprehension for sustainability of environment and global stability. This chapter aims to discuss pesticides, their types, routes of their exposure, human health concerns related to them, methods to stop using them, and a future scenario of the world after eradicating pesticides.

Pyrethroid epidemiology: a quality-based review

Pyrethroids are commonly used around the home and in agricultural production to control insects. Human contact to one or more pyrethroid insecticides is likely. Numerous epidemiology studies have evaluated the association between health outcomes in humans and pyrethroid exposure. The purpose of this review was to identify and evaluate the quality of pyrethroid-related epidemiology studies that addressed chronic health effects, and compare findings with animal toxicology studies. We evaluated the quality of 61 studies published between 2000 and 2016 by using elements of outcome, exposure metric, exposure level, and study design. None of the 61 publications demonstrated strong quality for all elements. A few of the outcome measures were strong, particularly those relying upon medical diagnoses. Most of the pyrethroid epidemiology studies used a poor exposure metric, relying upon a single sample of pyrethroid urinary metabolites, which is subject to misclassification of past exposures. In addition, many studies were a cross-sectional design, preventing an evaluation of the temporality of the exposure-disease association. Furthermore, none of the effects observed in the epidemiological literature was concordant with toxicological effects noted in extensive testing of pyrethroids in animals. In order to provide more robust data on potential health outcomes from low dose exposure to pyrethroid insecticides, future epidemiological studies should fully characterize an adverse outcome, include exposure validation components, and quantify exposure over time.

Increased Frequency of Rheumatoid Arthritis and Allergic Rhinitis among Pesticide Sprayers and Associations with Pesticide Use

Objective: The aim of this study was to identify diseases linked with the pesticide sprayer occupation and explore possible associations with exposure history data. Methods: A cross sectional study was conducted among pesticide sprayers (n = 80) and the general population (n = 90) in Thessaly (Greece). Medical history, demographic characteristics and detailed exposure history were recorded by conducting personal interviews. Lifetime exposure indicators were calculated for several pesticide chemical subclasses. Moreover, organophosphate metabolite levels were quantified in urine samples of all participants by using gas chromatography-mass spectrometry (GC-MS). Multinomial analysis was used to determine associations between occupational pesticide exposure and diseases or disorders. Results: In the pesticide sprayers group, significantly higher frequencies for rheumatoid arthritis (RA) and allergic rhinitis were observed compared with the control group (p = 0.002 and p = 0.024 respectively). Within the pesticide sprayers group, high lifetime pesticide exposure was associated with increased risk for reporting RA (OR: 43.07 95% CI: 3.09–600.67) and allergic rhinitis (OR: 9.72 95% CI: 2.31–40.89), compared with low pesticide exposure. Exposure to organophsphate, guanidine and quinone pesticides were associated with RA while organophosphates, pyrethroids and paraquat were associated with allergic rhinitis. Despite the higher levels of certain pesticide metabolites observed among participants with rheumatoid arthritis, the differences were not statistically significant. One metabolite (diethylthiophosphate) was found to be significantly increased in allergic rhinitis cases (p = 0.037). Conclusions: The results from the current study suggest a possible association of occupational pesticide exposure with RA and allergic rhinitis that should be further investigated.

Oxidative stress and genetic damage among workers exposed primarily to organophosphate and pyrethroid pesticides

The indiscriminate use of pesticides in agriculture and public health campaigns has been associated with an increase of oxidative stress and DNA damage, resulting in health outcomes. Some defense mechanisms against free radical-induced oxidative damage include the antioxidant enzyme systems. The aim of this study was to determine the levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and the relationship of antioxidant enzyme levels with DNA damage among sprayers (workers) occupationally exposed to pesticides. The determinations of MDA and antioxidant enzymes were performed spectrophotometrically. The genotoxic effects were evaluated using the comet assay. The results showed a marginally significant decrease in SOD and CAT activities in the high exposure group compared to the control group. For MDA, statistically significant differences were found among people working long term vs. those working temporarily (P = 0.02) as sprayers. In the moderate exposure group, a positive correlation was observed between MDA levels and GPx activity. In the high exposure group, a negative correlation was observed between GR and CAT activities, and between MDA levels and GPx activities. Furthermore, in the high exposure group, a positive correlation between DNA damage parameters and MDA levels was observed. The results suggest an important role of antioxidant enzymes for the protection of DNA damage caused by occupational exposure to pesticides.

Pesticides are Associated with Allergic and Non-Allergic Wheeze among Male Farmers

BACKGROUND

Growing evidence suggests that pesticide use may contribute to respiratory symptoms.

OBJECTIVE

We evaluated the association of currently used pesticides with allergic and non-allergic wheeze among male farmers.

METHODS

Using the 2005-2010 interview data of the Agricultural Health Study, a prospective study of farmers in North Carolina and Iowa, we evaluated the association between allergic and non-allergic wheeze and self-reported use of 78 specific pesticides, reported by ≥ 1% of the 22,134 men interviewed. We used polytomous regression models adjusted for age, BMI, state, smoking, and current asthma, as well as for days applying pesticides and days driving diesel tractors. We defined allergic wheeze as reporting both wheeze and doctor-diagnosed hay fever (n = 1,310, 6%) and non-allergic wheeze as reporting wheeze but not hay fever (n = 3,939, 18%); men without wheeze were the referent.

RESULTS

In models evaluating current use of specific pesticides, 19 pesticides were significantly associated (p < 0.05) with allergic wheeze (18 positive, 1 negative) and 21 pesticides with non-allergic wheeze (19 positive, 2 negative); 11 pesticides were associated with both. Seven pesticides (herbicides: 2,4-D and simazine; insecticides: carbaryl, dimethoate, disulfoton, and zeta-cypermethrin; and fungicide pyraclostrobin) had significantly different associations for allergic and non-allergic wheeze. In exposure-response models with up to five exposure categories, we saw evidence of an exposure-response relationship for several pesticides including the commonly used herbicides 2,4-D and glyphosate, the insecticides permethrin and carbaryl, and the rodenticide warfarin.

CONCLUSIONS

These results for farmers implicate several pesticides that are commonly used in agricultural and residential settings with adverse respiratory effects.

Lifetime allergic rhinitis prevalence among US primary farm operators: findings from the 2011 Farm and Ranch Safety survey

PURPOSE

Allergic rhinitis is associated with decreased quality of life, and reduced workplace performance and productivity. This study investigated the prevalence of lifetime allergic rhinitis and factors associated with allergic rhinitis among US primary farm operators.

METHODS

The 2011 Farm and Ranch Safety Survey data collected from 11,210 active farm operators were analyzed. Survey respondents were determined to have lifetime allergic rhinitis based on a "yes" response to the question: "Have you ever been told by a doctor, nurse, or other health professional that you had hay fever, seasonal allergies, or allergic rhinitis?" Data were weighted to produce nationally representative estimates.

RESULTS

An estimated 30.8% of the 2.1 million active farm operators had lifetime allergic rhinitis in 2011. The allergic rhinitis prevalence varied by demographic and farm characteristics. Farm operators with allergic rhinitis were 1.38 (95% CI 1.22-1.56) times more likely to be exposed to pesticides compared with operators with no allergic rhinitis. The association with pesticide exposure for allergic rhinitis and current asthma, and allergic rhinitis alone was statistically significant and greater than that for current asthma alone.

CONCLUSION

Certain groups of farm operators may be at increased risk of allergic rhinitis. Studies should further investigate the association of allergic rhinitis with specific pesticide exposure.

Pesticide exposures and respiratory health in general populations

Human exposures to pesticides can occur in the workplace, in the household and through the ambient environment. While several articles have reviewed the impact of pesticide exposures on human respiratory health in occupational settings, to the best of our knowledge, this article is the first one to review published studies on the association between pesticide exposures and human respiratory health in the general populations. In this article, we critically reviewed evidences up to date studying the associations between non-occupational pesticide exposures and respiratory health in general populations. This article also highlighted questions arising from these studies, including our recent analyses using the data from the Canadian Health Measures Survey (CHMS), for future research. We found few studies have addressed the impact of environmental pesticide exposures on respiratory health, especially on lung function, in general populations. In the studies using the data from CHMS Cycle 1, exposures to OP insecticides, pyrethroid insecticides, and the organochlorine pesticide DDT were associated with impaired lung function in the Canadian general population, but no significant associations were observed for the herbicide 2,4-D. Future research should focus on the potential age-specific and pesticide-specific effect on respiratory health in the general population, and repeated longitudinal study design is critical for assessing the temporal variations in pesticide exposures. Research findings from current studies of non-occupational pesticide exposures and their health impact in general population will help to improve the role of regulatory policies in mitigating pesticide-related public health problems, and thereafter providing greater benefit to the general population.

Asthma associated with pesticide exposure among women in rural Western Cape of South Africa

BACKGROUND

Few studies have investigated asthma and pesticides among women farm workers in developing countries.

METHODS

A cross-sectional study was conducted to investigate the association between pesticides and asthma among rural women (n = 211). Outcome measurements included respiratory symptoms (European Community Respiratory Health Survey questionnaire), immunological status (Phadiatop, serum IgE to mite allergens) and lower airway inflammation (fractional exhaled nitric oxide (FeNO) levels). Exposure variables included self-reported pesticide exposure and whole blood cholinesterase (ChE).

RESULTS

The prevalence of ocular-nasal symptoms (ONS), doctor-diagnosed asthma and current asthma was 24%, 11%, and 6% respectively. ONS was positively associated with re-entering a sprayed field (OR = 2.97; CI: 0.93-9.50). Asthma symptom score was associated with low ChE (OR = 1.93; CI: 1.09-3.44). Participants with high FeNO (>50 ppb) also had an elevated odds of having low ChE (OR = 4.8; CI: 0.80-28.00).

CONCLUSION

Pesticide exposure among women farm workers is associated with increased risk of ocular nasal symptoms and an elevated asthma symptom score.

Relationship between urine dichlorophenol levels and asthma morbidity

BACKGROUND

Chlorinated phenols are associated with atopic conditions, but it is not known whether they are associated with wheeze or asthma and whether atopy is involved in these associations.

OBJECTIVES

To test the association between urine levels of 2 dichlorophenols (2,4- and 2,5-dichlorophenols) and asthma morbidity in atopic and nonatopic wheezers and between total serum immunoglobulin E (IgE) levels.

METHODS

Data from a sample of 2,125 participants at least 6 years old from the US National Health and Nutrition Examination Survey 2005 to 2006 were analyzed. Asthma morbidity data were available for those participants who reported wheezing in the past year ("wheezers"; n = 250). This subsample was categorized as atopic or nonatopic.

RESULTS

Atopic wheezers with higher 2,5-dichlorophenol levels were more frequently diagnosed with asthma by a physician (odds ratio [OR] 4.7 for highest vs lowest tertile, P < .001), required more prescriptions for asthma medications (OR 2.2, P = .046), and reported more exercise-induced wheezing (OR 5.8, P = .045) than atopic wheezers with low dichlorophenol levels. Atopic wheezers with higher 2,5- or 2,4-dichloropheonol levels also were more likely to miss work or school because of wheezing (OR 10.0, P < .001; OR 11.4, P < .01, respectively). In contrast, in nonatopic wheezers, there were no significant associations between dichlorophenol levels and asthma morbidity measurements. The 2 dichlorophenol metabolites were positively associated with increased serum IgE levels in the larger study sample.

CONCLUSION

These findings indicate that in patients with atopy and a history of wheezing, asthma morbidity is associated with high urinary dichlorophenol levels. Increased urine dichlorophenol levels are associated with higher total serum IgE.

Occupational pesticide exposures and respiratory health

Pesticides have been widely used to control pest and pest-related diseases in agriculture, fishery, forestry and the food industry. In this review, we identify a number of respiratory symptoms and diseases that have been associated with occupational pesticide exposures. Impaired lung function has also been observed among people occupationally exposed to pesticides. There was strong evidence for an association between occupational pesticide exposure and asthma, especially in agricultural occupations. In addition, we found suggestive evidence for a link between occupational pesticide exposure and chronic bronchitis or COPD. There was inconclusive evidence for the association between occupational pesticide exposure and lung cancer. Better control of pesticide uses and enforcement of safety behaviors, such as using personal protection equipment (PPE) in the workplace, are critical for reducing the risk of developing pesticide-related symptoms and diseases. Educational training programs focusing on basic safety precautions and proper uses of personal protection equipment (PPE) are possible interventions that could be used to control the respiratory diseases associated with pesticide exposure in occupational setting.

Exacerbation of symptoms in agricultural pesticide applicators with asthma

PURPOSE

Exacerbation is a critical event in asthma management. We investigated whether exacerbation of symptoms is associated with farming exposures among agricultural pesticide applicators with asthma.

METHODS

Participants were pesticide applicators with active asthma (wheezing and breathing problems in past 12 months) who completed enrollment questionnaires for the Agricultural Health Study (AHS). Exacerbation of asthma was defined as having visited a hospital emergency room or doctor for an episode of wheezing or whistling in the past 12 months. Exposures of interest were using 36 specific pesticides in the past 12 months and conducting various agricultural activities. Adjusted odds ratios (ORs) were estimated by logistic regression while controlling for potential confounders.

RESULTS

The 926 AHS adult pesticide applicators with active asthma included 202 (22%) with exacerbation. Inverse associations with exacerbation were observed for two herbicides [glyphosate, odds ratio (OR) = 0.5, 95% confidence interval (CI) 0.3, 0.8, and paraquat, OR = 0.3, 95% CI 0.1, 0.9] and several agricultural activities (repairing engines, grinding metal, driving diesel tractors, and performing veterinary procedures). Only asthma cases with allergies (i.e., doctor-diagnosed hay fever or eczema, 46%) had positive exacerbation-pesticide associations, with OR = 2.1 (95% CI 1.1, 4.1) for the herbicide pendimethalin and OR = 10.2 (95% CI 1.9, 55) for the insecticide aldicarb.

CONCLUSIONS

The inverse associations with two pesticides and specific farm activities are consistent with the possibility that asthma cases prone to exacerbation may avoid exposures that trigger symptoms. Although limited by small sample size and a cross-sectional design, our study suggests that use of specific pesticides may contribute to exacerbation of asthma among individuals with allergies.

Pesticides and human chronic diseases: evidences, mechanisms, and perspectives

Along with the wide use of pesticides in the world, the concerns over their health impacts are rapidly growing. There is a huge body of evidence on the relation between exposure to pesticides and elevated rate of chronic diseases such as different types of cancers, diabetes, neurodegenerative disorders like Parkinson, Alzheimer, and amyotrophic lateral sclerosis (ALS), birth defects, and reproductive disorders. There is also circumstantial evidence on the association of exposure to pesticides with some other chronic diseases like respiratory problems, particularly asthma and chronic obstructive pulmonary disease (COPD), cardiovascular disease such as atherosclerosis and coronary artery disease, chronic nephropathies, autoimmune diseases like systemic lupus erythematous and rheumatoid arthritis, chronic fatigue syndrome, and aging. The common feature of chronic disorders is a disturbance in cellular homeostasis, which can be induced via pesticides' primary action like perturbation of ion channels, enzymes, receptors, etc., or can as well be mediated via pathways other than the main mechanism. In this review, we present the highlighted evidence on the association of pesticide's exposure with the incidence of chronic diseases and introduce genetic damages, epigenetic modifications, endocrine disruption, mitochondrial dysfunction, oxidative stress, endoplasmic reticulum stress and unfolded protein response (UPR), impairment of ubiquitin proteasome system, and defective autophagy as the effective mechanisms of action.

Dichlorophenol-containing pesticides and allergies: results from the US National Health and Nutrition Examination Survey 2005-2006

BACKGROUND

Epidemiologic studies support the hypothesis that reduced microbial exposure in westernized societies promotes atopy. Dichlorophenols are widely used as pesticides and for chlorination of water. They have a strong bactericidal effect that could affect microflora in the environment. However, it is unknown whether their use is associated with a higher prevalence of allergies.

OBJECTIVE

To test the association between exposure to environmental pesticides represented by dichlorophenols and allergic sensitization measured by allergen-specific serum IgE levels in a US nationally representative sample of 2,211 persons 6 years and older in the National Health and Nutrition Examination Survey 2005-2006.

METHODS

Exposure to dichlorophenols was defined as high if their levels in urine were present at the 75th percentile and above. Association of the high exposure to dichlorophenols with sensitization to food and environmental allergens was assessed in logistic regression models after adjustment for sample weights and potential confounders.

RESULTS

Sensitizations to 1 or more food allergens were more common in those with exposure to 2 dichlorophenol metabolites. After multivariable adjustment, urine dichlorophenol levels at the 75th percentile and above were associated with the presence of sensitization to foods (odds ratio, 1.8; 95% confidence interval, 1.2-2.5; P = .003). No significant association was found between dichlorophenol exposure and sensitization to aeroallergens alone.

CONCLUSION

High urine levels of dichlorophenols are associated with the presence of sensitization to foods in a US population. Excessive use of dichlorophenols may contribute to the increasing incidence of food allergies in westernized societies.

Do workplace and home protective practices protect farm workers? Findings from the "For Healthy Kids" study

OBJECTIVE

To assess associations of protective workplace and home practices with pesticide exposure levels.

METHODS

Using data from orchard workers in the Yakima Valley, Washington, we examined associations of workplace and home protective practices with (1) urinary metabolite concentrations of dimethylthiophosphate (DMTP) in adults and children aged 2 to 6 years and (2) azinphos-methyl levels in house and vehicle dust.

RESULTS

Data were collected from 95 orchard workers and 94 children. Contrary to expectation, adult farm workers who wore boots or washed hands using hand sanitizer had higher concentrations of DMTP than those who did not. Children who attended daycare had higher DMTP concentrations than children who did not.

CONCLUSIONS

Few workplace or home practices were associated with pesticide exposure levels; workers who used hand sanitizer had higher concentrations of DMTP, as did children who attended daycare.

Review of 2,4-dichlorophenoxyacetic acid (2,4-D) biomonitoring and epidemiology

A qualitative review of the epidemiological literature on the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) and health after 2001 is presented. In order to compare the exposure of the general population, bystanders and occupational groups, their urinary levels were also reviewed. In the general population, 2,4-D exposure is at or near the level of detection (LOD). Among individuals with indirect exposure, i.e. bystanders, the urinary 2,4-D levels were also very low except in individuals with opportunity for direct contact with the herbicide. Occupational exposure, where exposure was highest, was positively correlated with behaviors related to the mixing, loading and applying process and use of personal protection. Information from biomonitoring studies increases our understanding of the validity of the exposure estimates used in epidemiology studies. The 2,4-D epidemiology literature after 2001 is broad and includes studies of cancer, reproductive toxicity, genotoxicity, and neurotoxicity. In general, a few publications have reported statistically significant associations. However, most lack precision and the results are not replicated in other independent studies. In the context of biomonitoring, the epidemiology data give no convincing or consistent evidence for any chronic adverse effect of 2,4-D in humans.

Occupational safety of farmers in the vegetable industry

This study aimed to determine unsafe farming practices, nonergonomically designed equipment, and possible adverse health effects of pesticide exposure. Data were gathered with a structured survey, physical examination and blood extraction. Environmental monitoring was done for vegetables to determine multipesticide residue. Forty-eight percent of respondents reported feeling sick because of work. Vegetable residue was found in 16.67% of the samples. Vegetable profenofos of appoximately1 mg exceeded the necessary average daily intake of a maximum of 0.006 mg. Data also showed nonergonomically designed tools and unsafe work practices that increased pesticide exposure such as re-entering recently sprayed areas, a damaged backpack sprayer, spills during spraying, and no ventilation in greenhouses.

Epidemiologic studies of glyphosate and non-cancer health outcomes: a review

The United States (US) Environmental Protection Agency (EPA) and other regulatory agencies around the world have registered glyphosate as a broad-spectrum herbicide for use on multiple food and non-food use crops. To examine potential health risks in humans, we searched and reviewed the literature to evaluate whether exposure to glyphosate is associated causally with non-cancer health risks in humans. We also reviewed biomonitoring studies of glyphosate to allow for a more comprehensive discussion of issues related to exposure assessment and misclassification. Cohort, case-control and cross-sectional studies on glyphosate and non-cancer outcomes evaluated a variety of endpoints, including non-cancer respiratory conditions, diabetes, myocardial infarction, reproductive and developmental outcomes, rheumatoid arthritis, thyroid disease, and Parkinson's disease. Our review found no evidence of a consistent pattern of positive associations indicating a causal relationship between any disease and exposure to glyphosate. Most reported associations were weak and not significantly different from 1.0. Because accurate exposure measurement is crucial for valid results, it is recommended that pesticide-specific exposure algorithms be developed and validated.

Occupational rhinitis: consensus on diagnosis and medicolegal implications

PURPOSE OF REVIEW

Work-related rhinitis is a common disease in many working groups, frequently associated with asthma. The purpose of this review is to summarize the specific literature published within the past 12 months, to discuss the diagnostic workup and to illustrate the medicolegal aspects pertaining to this disease.

RECENT FINDINGS

Recently, there has been a growing scientific interest in work-related rhinitis, which includes both occupational rhinitis and work-exacerbated rhinitis. The epidemiological relevance and the relationships to asthma have been evaluated. New etiologic agents and populations at risk have been identified. A new definition and classification, and a diagnostic algorithm, have been proposed.

SUMMARY

In consideration of the epidemiological relevance and of the medicolegal implications, occupational rhinitis should be considered in daily clinical practice by all physicians. In adults with late-onset rhinitis, occupational causes should be queried and patients in whom an occupational association is suspected should be referred for specific assessments.

Occupational rhinitis and asthma: where do we stand, where do we go?

This review provides an overview of current and emerging issues regarding occupational rhinitis (OR) and occupational asthma (OA), focusing on studies discussing concepts and results that are relevant to both diseases. OA and OR are conditions that affect the upper and lower airways, are characterized by reduced airway caliber and hyperresponsiveness and by inflammation, and are caused by agents present in the workplace. To explain disease expression, research is moving from the T-helper type 1/type 2 cells paradigm to consider the contribution of diverse alternative pathways such as neural inflammation, a dysfunctional epithelial barrier, and autoimmune mechanisms, among others. Objective assessment of OR and OA has been improved and tested for research and, currently, clinical application. Further developments in the field of OR are expected to lead to more generalized clinical applications, following the example of what has been achieved for OA.

Pest and allergen exposure and abatement in inner-city asthma: a work group report of the American Academy of Allergy, Asthma & Immunology Indoor Allergy/Air Pollution Committee

Our work group report details the importance of pest allergen exposure in inner-city asthma. We will focus specifically on mouse and cockroach exposure. We will discuss how exposure to these pests is common in the inner city and what conditions exist in urban areas that might lead to increased exposure. We will discuss how exposure is associated with allergen sensitization and asthma morbidity. Finally, we will discuss different methods of intervention and the effectiveness of these tactics.

Rhinitis associated with pesticide use among private pesticide applicators in the agricultural health study

Farmers commonly experience rhinitis but the risk factors are not well characterized. The aim of this study was to analyze cross-sectional data on rhinitis in the past year and pesticide use from 21,958 Iowa and North Carolina farmers in the Agricultural Health Study, enrolled 1993-1997, to evaluate pesticide predictors of rhinitis. Polytomous and logistic regression models were used to assess association between pesticide use and rhinitis while controlling for demographics and farm-related exposures. Sixty-seven percent of farmers reported current rhinitis and 39% reported 3 or more rhinitis episodes. The herbicides glyphosate [odds ratio (OR) = 1.09, 95% confidence interval (95% CI) = 1.05-1.13] and petroleum oil (OR = 1.12, 95% CI = 1.05-1.19) were associated with current rhinitis and increased rhinitis episodes. Of the insecticides, four organophosphates (chlorpyrifos, diazinon, dichlorvos, and malathion), carbaryl, and use of permethrin on animals were predictors of current rhinitis. Diazinon was significant in the overall polytomous model and was associated with an elevated OR of 13+ rhinitis episodes (13+ episodes OR = 1.23, 95% CI = 1.09-1.38). The fungicide captan was also a significant predictor of rhinitis. Use of petroleum oil, use of malathion, use of permethrin, and use of the herbicide metolachlor were significant in exposure-response polytomous models. Specific pesticides may contribute to rhinitis in farmers; agricultural activities did not explain these findings.

Chronic exposures to cholinesterase-inhibiting pesticides adversely affect respiratory health of agricultural workers in India

OBJECTIVE

The impact of long term exposure to cholinesterase (ChE)-inhibiting organophosphate (OP) and carbamate (C) pesticides on the respiratory health of agricultural workers in India was investigated.

METHODS

Three hundred and seventy-six nonsmoking agricultural workers (median age 41 yr) from eastern India who sprayed OP and C pesticides in the field and 348 age- and sex-matched control subjects with non-agricultural occupations from the same locality were enrolled. Prevalence of respiratory symptoms was obtained by questionnaire survey, and pulmonary function tests were carried out by spirometry. Chronic obstructive pulmonary disease (COPD) was diagnosed by the Global Obstructive Lung Disease (GOLD) criteria, and erythrocyte acetylcholinesterase (AChE) was measured by the Ellman method.

RESULTS

Agricultural workers had greater prevalences of upper and lower respiratory symptoms, and appreciable reduction in spirometric measurements. Overall, lung function reduction was noted in 48.9% of agricultural workers compared with 22.7% of control, and a restrictive type of deficit was predominant. COPD was diagnosed in 10.9% of agricultural workers compared with 3.4% of controls (p<0.05 in chi(2) test), and the severity of the disease was greater in agricultural workers. Red blood cell (RBC) AChE was lowered by 34.2% in agricultural workers, and the fall in AChE level was positively associated with respiratory symptoms, lung function decrement and COPD after controlling for education and income as potential confounders.

CONCLUSIONS

Long-term exposure to cholinesterase-inhibiting agricultural pesticides currently in use in India is associated with a reduction in lung function, COPD and a rise in respiratory symptoms.