Agricultural Exposure Research Articles

380 Multiple pesticide exposures and the risk of multiple myeloma in Canadian men

ObjectivesMultiple myeloma (MM) has been linked to certain agricultural exposures, including pesticides, however the effects of exposure to multiple pesticides have not been explored. This analysis investigated the association between...

305 Engine exhaust exposure and lung cancer risk in farming

ObjectivesFarmers have lower lung cancer rates than the general population, due to lower rates of smoking and possibly exposure to endotoxins. Farmers do, however, have exposure to potential lung carcinogens...

Correlation between Cholinesterase and Paraoxonase 1 Activities:Case Series of Pesticide Poisoning Subjects.

Acute exposure to pesticide due to suicidal poisoning is the most extensive cause of pesticide exposure, compared with all other causes including agricultural or industrial exposure. Organophosphate (OP) and carbamate group of pesticides can inhibit acetylcholinesterase; on the other hand, paraoxonase1 can detoxify organophosphate poisoning by hydrolyzing organophosphate metabolites. We have compared the serum paraoxonase1 status and cholinesterase activity of subjects who attempted to commit suicide by consuming OP pesticide. Cholinesterase and paraoxonase1 activity were measured spectrophotometrically using butyrylthiocholine and phenyl acetate as substrates, respectively. A positive correlation was found between serum paraoxonase1 activity and cholinesterase activity among pesticide consumed subjects. Our results suggest that subjects with higher paraoxonase1 activity may have a better chance of detoxifying the lethal effect of acute organophosphate poisoning.

A new model for the prediction of agricultural operator exposure during professional application of plant protection products in outdoor crops

A new predictive model for the estimation of agricultural operator exposure has been developed on the basis of new exposure data to improve the current agricultural operator exposure and risk assessment in the EU. The new operator exposure model represents current application techniques and practices in EU Member States (MS) and is applicable for national or zonal authorisation of plant protection products as well as for approval of active substances in plant protection products (PPP) supporting a stepwise risk assessment. 34 unpublished exposure studies conducted between 1994 and 2009 were evaluated for the new model. To ensure a very high quality of data the studies had to meet a set of quality criteria, e.g. GLP conformity or compliance with OECD guidance. Exposure data and supplementary information on the trials were used for a statistical analysis of exposure factors. The statistical analyses resulted in six validated models for typical outdoor scenarios of pesticide mixing/loading and application. As a major factor contributing to the exposure of operators, the amount of active substance used per day was identified. Other parameters such as formulation type, droplet size, presence of a cabin or density of the canopy were selected as factors for sub-scenarios. For two scenarios the corresponding datasets were too small to identify reliable exposure factors; instead the relevant percentiles of the exposure distribution were used. The whole project report on the development of the new model (including the underlying study data) and the corresponding exposure calculators will be published at the BfR website (http://www.bfr.bund.de) after confirmation of the model by EU MS.

Agricultural exposures and chronic bronchitis: findings from the AGRICAN (AGRIculture and CANcer) cohort

PurposeLivestock farming has been recognized as a risk factor for chronic bronchitis (CB). The role of crop farming, however, has been less studied. We sought to assess the role of a large range of farming activities on the risk of CB in the French agricultural cohort AGRICAN (AGRIculture and CANcer). MethodsData on respiratory health and farming activities were collected by questionnaire from 2005 to 2007. Associations between farming activities and self-reported doctor's diagnosis of CB were estimated by a logistic regression adjusted for confounders. ResultsCB was reported by 1207 farmers (8.4%). Two farming activities were associated with CB: cattle raising (odds ratio [OR] 1.24, 95% confidence interval 1.03–1.48), and potato production (OR 1.33, 95% confidence interval 1.13–1.57). Associations were more pronounced in small-scale cattle raising and in large-scale potato production, in particular among the longest exposed workers (≥20 years). Pesticide poisoning and exposure to pesticides in potato farmers were significantly associated with CB risk (OR 1.64 and OR 1.63, respectively). ConclusionsThis analysis suggests that other agricultural settings not previously reported, such as potato production, may be a risk factor for CB. The nature and circumstances of exposure to hazardous agents need to be further explored.

Agricultural Exposures and Stroke Mortality in the Agricultural Health Study

Exposures associated with common agricultural activities may increase risk of stroke. The authors evaluated associations between self-reported agricultural activities including pesticide use and handling of crops and stroke mortality among 51,603 male pesticide applicators enrolled in the Agricultural Health Study (AHS). Vital status was obtained through 2008. Stroke mortality was defined by underlying or contributing cause of death (ICD-9 430–438, ICD-10 I60–I69). Information regarding lifetime pesticide use, working with crops or animals, engagement in other agricultural activities, and potential confounders was self-reported at enrollment. Cox proportional hazards models, with age as the time scale, were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) adjusted for state of residence, smoking status, and alcohol consumption. Median follow-up time was 13 yr, during which 308 stroke deaths occurred. No measure of overall or specific pesticide use was positively associated with mortality due to stroke. Stroke mortality was inversely associated with handling hay, grain, or silage at least once each year as reported at enrollment (HR: 0.75; 95% CI: 0.58, 0.98). There was no evidence of an association between pesticide use and stroke mortality. The inverse association between handling of hays and grains and stroke mortality may be due to (1) those engaging in such activities being healthier than those who did not or (2) exposure to some biological agent present in hays and grains. Further investigation of incident stroke, rather than stroke mortality, as well as stroke subtypes, is needed to determine the full role of agricultural exposures and stroke.

Does agricultural trade affect productivity? Evidence from Chilean farms

This paper analyzes the relationship between trade and agricultural productivity in Chile, a middle-income country with a recent noticeable history of agricultural trade. This study uses an agricultural commodity trade exposure index in a cross-sectional analysis of more than 70,000 farms to study the relationship between the trade exposure of agricultural commodities and the yields reported by these farms in the 1997 Chilean agricultural census. In order to capture both import and export exposure we subdivide farms in two groups, according to the Chilean case: farms producing only importables such as grains (traditional crops), and farms producing both traditional crops and non-traditional agricultural commodities (products more related to export markets). We exclude from our analysis farms producing only non-traditional products because the census only reports yields for traditional crops. We employ a switching regression model to analyze the effects of trade exposure on traditional crop yields for both groups of farms. Results show that the trade exposure index is positively related to farm yields for both groups, but with a larger effect on farmers producing both traditional and non-traditional commodities. These results are important because they suggest that spillovers from both importables and exportables produce gains in the productivity of traditional crops.

Multiple pesticide exposures and the risk of multiple myeloma in Canadian men

Multiple myeloma (MM) has been linked to certain agricultural exposures, including pesticides. This analysis aimed to investigate the association between lifetime use of multiple pesticides and MM risk using two exposure metrics: number of pesticides used and days per year of pesticide use. A frequency-matched, population-based case-control study was conducted among men in six Canadian provinces between 1991 and 1994. Data from 342 MM cases and 1,357 controls were analyzed using logistic regression to calculate odds ratios (OR) and 95% confidence intervals. Pesticides were grouped by type, chemical class and carcinogenic potential, using a composite carcinogenic probability score. Selected individual pesticides were also examined. Regression models were adjusted for age, province of residence, use of proxy respondents, smoking and selected medical history variables. The overall pattern of results was complex. Positive trends in risk were observed for fungicides (ptrend=0.04) and pesticides classified as probably carcinogenic or higher (ptrend=0.03). Excess risks of MM were observed among men who reported using at least one carbamate pesticide (OR=1.94, 1.16-3.25), one phenoxy herbicide (OR=1.56, 1.09-2.25) and ≥3 organochlorines (OR=2.21, 1.05-4.66). Significantly higher odds of MM were seen for exposure to carbaryl (OR=2.71, 1.47-5.00) and captan (OR=2.96, 1.40-6.24). Use of mecoprop for >2 days per year was also significantly associated with MM (OR=2.15, 1.03-4.48). Focusing on multiple pesticide exposures is important because this more accurately reflects how exposures occur in occupational settings. Significant associations observed for certain chemical classes and individual pesticides suggest that these may be MM risk factors.

Proximity to animal or crop operations may be associated with de novo daptomycin-non-susceptible Enterococcus infection

Daptomycin-non-susceptible enterococci (DNSE) are emerging pathogens. We have previously reported de novo DNSE isolates in patients with agricultural activities and exposure to livestock. We studied the geographical distribution of the residencies of 34 patients with DNSE infections described in a tertiary centre over a 5-year period in an effort to explore the association between patients' residential locations and agricultural and farm lands. Nine patients had no prior exposure to daptomycin (de novo) and seven of these lived in areas with animal or crop operations. Of those living near an animal or crop operation, the mean number of operations in the proximity of the residence of patients with daptomycin-exposed DNSE was 13.8 (range 1-67) compared to 98.6 (3-529) for those patients with de novo DNSE (P = 0.0486). These data are consistent with previous reports that the transport of daptomycin resistance genes between animals and humans may be a possible mechanism for development of de novo daptomycin resistance in enterococci.

Occupational health outcomes for workers in the agriculture, forestry and fishing sector: Implications for immigrant workers in the southeastern US

Workers in the Agriculture, Forestry, and Fisheries (AgFF) sector experience exposures directly related to the work itself, as well as the physical environment in which the work occurs. Health outcomes vary from immediate to delayed, and from acute to chronic. We reviewed existing literature on the health outcomes of work in the AgFF sector and identified areas where further research is needed to understand the impact of these exposures on immigrant Latino workers in the southeastern US. Outcomes related to specific body systems (e.g., musculoskeletal, respiratory) as well as particular exposure sources (e.g., pesticides, noise) were reviewed. The most extensive evidence exists for agriculture, with a particular focus on chemical exposures. Little research in the southeastern US has examined health outcomes of exposures of immigrant workers in forestry or fisheries. As the AgFF labor force includes a growing number of Latino immigrants, more research is needed to characterize a broad range of exposures and health outcomes experienced by this population, particularly in forestry and fisheries.

Implications of pesticide usage in Nigeria

The occurrence of pesticides in our environment as a result of the indiscriminate or intentional use has resulted in its persistence in the environment, thereby affecting the ecosystems and non target organisms. Acute and chronic pesticide poisoning usually results from consumption of contaminated food, chemical accident in industries and occupational exposure in agriculture. About 15,000 metric tons of pesticides comprising about 135 pesticide chemicals are imported annually into the country. They are the major causes of cancer, cardiovascular disease, dermatitis, birth defects, morbidity, impaired immune function, neurobehavioral disorder and allergy sensitization reaction. In Nigeria, food test carried out on 217 different food items revealed the presence of DDT, Aldrin and Dieldrin to be above maximum allowable concentration level which ranged from 1.2-2160μg kg-1. The detection of these pesticides in soil, drinking water and other animals is of great interest. The failure to establish data-base from past incidents in order to avert future occurrences has posed a huge problem to the society at large. The need for epidemiological data collection from past exposure, development of less toxic pesticides and legal requirement regarding toxicological and ecological effect before the importation of pesticides into the country will further reduce the impact of toxic pesticides on human health in the country.Key words: Pesticides, Environment, Health, Pollution, Nigeria.

Heat Exposure, Cardiovascular Stress and Work Productivity in Rice Harvesters in India: Implications for a Climate Change Future

Excessive workplace heat exposures create well-known risks of heat stroke, and it limits the workers' capacity to sustain physical activity. There is very limited evidence available on how these effects reduce work productivity, while the quantitative relationship between heat and work productivity is an essential basis for climate change impact assessments. We measured hourly heat exposure in rice fields in West Bengal and recorded perceived health problems via interviews of 124 rice harvesters. In a sub-group (n = 48) heart rate was recorded every minute in a standard work situation. Work productivity was recorded as hourly rice bundle collection output. The hourly heat levels (WBGT = Wet Bulb Globe Temperature) were 26-32°C (at air temperatures of 30-38°C), exceeding international standards. Most workers reported exhaustion and pain during work on hot days. Heart rate recovered quickly at low heat, but more slowly at high heat, indicating cardiovascular strain. The hourly number of rice bundles collected was significantly reduced at WBGT>26°C (approximately 5% per°C of increased WBGT). We conclude that high heat exposure in agriculture caused heat strain and reduced work productivity. This reduction will be exacerbated by climate change and may undermine the local economy.

Agricultural Exposures and Stroke Mortality in the Agricultural Health Study

Agricultural Exposures and Stroke Mortality in the Agricultural Health Study

Vitamin D Treatment Modulates Organic Dust–Induced Cellular and Airway Inflammatory Consequences

Exposure to organic dusts elicits airway inflammatory diseases. Vitamin D recently has been associated with various airway inflammatory diseases, but its role in agricultural organic dust exposures is unknown. This study investigated whether vitamin D reduces organic dust-induced inflammatory outcomes in cell culture and animal models. Organic dust extracts obtained from swine confinement facilities induced neutrophil chemokine production (human IL-8, murine CXCL1/CXCL2). Neutrophil chemokine induction was reduced in human blood monocytes, human bronchial epithelial cells, and murine lung slices pretreated with 1,25-(OH)(2) D(3) . Intranasal inhalation of organic dust extract induced neutrophil influx, and CXCL1/CXCL2 release was also decreased in mice fed a relatively high vitamin D diet as compared to mice fed a low vitamin D diet. These findings were associated with reduced tracheal epithelial cell PKCα and PKCε activity and whole lung TLR2 and TLR4 gene expression. Collectively, vitamin D plays a role in modulating organic dust-induced airway inflammatory outcomes.

Probabilistic risk assessment of insecticide concentrations in agricultural surface waters: a critical appraisal

Due to the specific modes of action and application patterns of agricultural insecticides, the insecticide exposure of agricultural surface waters is characterized by infrequent and short-term insecticide concentration peaks of high ecotoxicological relevance with implications for both monitoring and risk assessment. Here, we apply several fixed-interval strategies and an event-based sampling strategy to two generalized and two realistic insecticide exposure patterns for typical agricultural streams derived from FOCUS exposure modeling using Monte Carlo simulations. Sampling based on regular intervals was found to be inadequate for the detection of transient insecticide concentrations, whereas event-triggered sampling successfully detected all exposure incidences at substantially lower analytical costs. Our study proves that probabilistic risk assessment (PRA) concepts in their present forms are not appropriate for a thorough evaluation of insecticide exposure. Despite claims that the PRA approach uses all available data to assess exposure and enhances risk assessment realism, we demonstrate that this concept is severely biased by the amount of insecticide concentrations below detection limits and therefore by the sampling designs. Moreover, actual insecticide exposure is of almost no relevance for PRA threshold level exceedance frequencies and consequential risk assessment outcomes. Therefore, we propose a concept that features a field-relevant ecological risk analysis of agricultural insecticide surface water exposure. Our study quantifies for the first time the environmental and economic consequences of inappropriate monitoring and risk assessment concepts used for the evaluation of short-term peak surface water pollutants such as insecticides.

Breast cancer risk in relation to occupations with exposure to carcinogens and endocrine disruptors: a Canadian case-control study.

BackgroundEndocrine disrupting chemicals and carcinogens, some of which may not yet have been classified as such, are present in many occupational environments and could increase breast cancer risk. Prior research has identified associations with breast cancer and work in agricultural and industrial settings. The purpose of this study was to further characterize possible links between breast cancer risk and occupation, particularly in farming and manufacturing, as well as to examine the impacts of early agricultural exposures, and exposure effects that are specific to the endocrine receptor status of tumours.Methods1005 breast cancer cases referred by a regional cancer center and 1146 randomly-selected community controls provided detailed data including occupational and reproductive histories. All reported jobs were industry- and occupation-coded for the construction of cumulative exposure metrics representing likely exposure to carcinogens and endocrine disruptors. In a frequency-matched case–control design, exposure effects were estimated using conditional logistic regression.ResultsAcross all sectors, women in jobs with potentially high exposures to carcinogens and endocrine disruptors had elevated breast cancer risk (OR = 1.42; 95% CI, 1.18-1.73, for 10 years exposure duration). Specific sectors with elevated risk included: agriculture (OR = 1.36; 95% CI, 1.01-1.82); bars-gambling (OR = 2.28; 95% CI, 0.94-5.53); automotive plastics manufacturing (OR = 2.68; 95% CI, 1.47-4.88), food canning (OR = 2.35; 95% CI, 1.00-5.53), and metalworking (OR = 1.73; 95% CI, 1.02-2.92). Estrogen receptor status of tumors with elevated risk differed by occupational grouping. Premenopausal breast cancer risk was highest for automotive plastics (OR = 4.76; 95% CI, 1.58-14.4) and food canning (OR = 5.70; 95% CI, 1.03-31.5).ConclusionsThese observations support hypotheses linking breast cancer risk and exposures likely to include carcinogens and endocrine disruptors, and demonstrate the value of detailed work histories in environmental and occupational epidemiology.

The Impact of Agent Orange Exposure On Presentation and Prognosis of Patients with Chronic Lymphocytic Leukemia (CLL): An Exploratory Analysis

Abstract 4575 Background:From 1962–1971, 19 million gallons of Agent Orange (AO) and other herbicides were sprayed in South Vietnam and Cambodia to destroy dense jungle and crops used to conceal and feed enemy troops. In 2004, the Department of Veterans Affairs added chronic lymphocytic leukemia (CLL) to the list of Veterans Diseases Associated with Agent Orange, based upon data from agricultural exposure suggesting a causative association. In our retrospective cohort study, we evaluated if Agent Orange exposure was associated with an altered prognosis, time to treatment, or overall survival in veterans with newly diagnosed CLL. Methods:Clinical data was reviewed from 205 patients (pts) with CLL diagnosed from 2000–2010, identified through the Minneapolis MN VA Tumor Registry. Demographic information and laboratory parameters at diagnosis were collected, and Rai disease stage, marrow cytogenetics and lymphocyte doubling time were determined. Baseline labs, lymphocyte doubling time and time to initial CLL treatment were compared between exposed and unexposed pts using Student’s t-test. Kaplan Meier analysis compared overall survival between Agent Orange-exposed and unexposed pts. Results:Of the 199 (97%) pts confirmed to have CLL, 33 pts (16.6%) had Agent Orange exposure. Median follow-up time was 40.7 months (0.1–123 months). Pts with Agent Orange exposure were younger at diagnosis (61 vs. 72 years, p=0.001). WBC, hemoglobin, platelet count, Rai stage, and LDH at diagnosis were similar between the groups. Mean lymphocyte doubling time was comparable in exposed and unexposed pts (27 vs. 23 months (mos), respectively p=0.6). Cytogenetic analysis was limited as 24% of pts underwent a bone marrow biopsy. Poor risk cytogenetics (17p-, 11q-) were found in 1 of 10 (10%) pts with Agent Orange exposure and 3 of 37 (8%) unexposed pts. Time to first CLL treatment was significantly shorter in pts with Agent Orange exposure [9.6 (range 0.1–23.7) vs. 30.2 mos (range 0.1–163.3), respectively; p=0.02]. No significant difference in reason for treatment initiation was found between the groups. First line fludarabine therapy was used more often in exposed than unexposed pts, which may have been due to their younger age at diagnosis (100% AO exposed vs 36% AO unexposed, Fisher’s Exact p=0.01). No difference in overall survival was found between exposed and unexposed pts (Wilcoxon p=0.28). In a multivariable Cox regression model adjusted for age, Agent Orange exposure had a hazard ratio of death of 1.8 compared to non-exposure (95% CI: 0.7– 4.5, p = 0.24). Conclusions:CLL pts with Agent Orange exposure were diagnosed at a younger age and had a shorter time to first treatment, as compared to unexposed pts. Agent Orange exposure was not associated with a difference in prognosis in these patients. Although our hazard ratio result was not statistically significant, the high estimate of the mortality hazard combined with the relatively low numbers in the exposure group suggest that further examination of this issue in a larger patient population is warranted. Disclosures:No relevant conflicts of interest to declare.

A case report of severe atypical Weil’s syndrome in a department of gastroenterology

Leptospirosis is a reemerging zoonosis of global importance. Outbreaks are related to agricultural environments and exposure to flooding, and it is primarily found in tropical countries. Although cases with typical presentation are relatively easy to diagnose and treat, atypical cases make it difficult to differentiate from other diseases, especially those patients with digestive symptoms who present to departments of gastroenterology. A 54-year old man was admitted to hospital for jaundice, vomiting and fatty liver. leptospirosis antibody test and polymerase chain reaction did not help us to make a definite diagnosis. However, based on the patient’s presentation, physical characteristics and the muscular biopsy, Weil’s syndrome was diagnosed. This is a reminder that leptospirosis may be found in a developed city of southern China. Clinical experience, disease characterizations, physical signs and biopsy should be applied as more efficient ways to recognize atypical cases of leptospirosis.

Agricultural exposures and farm-related injuries among adolescents in rural China

This cross-sectional study explored the incidence of farm injuries and the relationship between agricultural exposures and injury among 2053 adolescents aged 13–19 years in Macheng, China. A comprehensive self-administered questionnaire...

Promoting and Protecting Worker Health and Safety in the Republic of Korea Agricultural Sector

ABSTRACT With the exception of agriculture, all other Republic of Korea industrial sectors have comprehensive systems in place for workplace surveillance (i.e., disease, injury, and exposure), research, and targeted interventions. However, because few statistics are available on the occupational health and safety conditions in the Republic of Korea agricultural sector, there is little information to guide interventions to prevent hazardous agricultural exposures. The scant information that is currently available suggests that agriculture ranks among the most hazardous industries in the Republic of Korea. Building on information obtained at the International Symposium on Development of Prevention Strategies for Agricultural Health and Safety held in Suwon, Republic of Korea, in 2005, and embellished with examples of surveillance, research, and intervention activities conducted in the United States and elsewhere, this article provides guidance to promote and protect the health of Korean agricultural workers. This information can also guide other countries to reduce agricultural hazards.