Farm Exposure Research Articles

Occupational Hazards: The Impact of Streptococcus suis Infections in Portuguese Pig Farming

Abstract Background In Portugal, the commensal and opportunistic bacteria Streptococcus suis is prevalent among pigs. Recognizing its public health significance, this systematic review investigates the relationship between occupational exposure in pig farming and the incidence of S. suis infections among workers. The importance of this study is to identify high-risk occupational activities and formulate effective public health interventions. Methods This review analyzed 20 scientific studies from 1986 to 2023 on human infections with S. suis in Portugal. The primary sources included articles in Portuguese from databases like MedLine, Scopus, and Pubmed. Studies were selected based on their focus on occupational exposure and the details provided on epidemiological context, clinical presentations, and outcomes. Results The review found that 85% of infection cases occurred in occupational settings, particularly among butchers (53%) and pig breeders or handlers (29%). Clinical manifestations predominantly included acute bacterial meningitis, with significant occurrences of neurosensory hearing loss as a sequelae. The average age of affected individuals was 44, predominantly male. Conclusions The study confirms a significant correlation between occupational exposure in pig farming and S. suis infections in humans. The findings underscore the need for stringent occupational health measures and integrated approaches encompassing human, animal, and environmental health under the One Health initiative. Innovations in public health interventions recommended include enhanced surveillance, improved workplace hygiene, and targeted health education for at-risk populations. Key messages • Occupational exposure in pig farming is a significant risk factor for S. suis infections in humans. • Integrative One Health approaches are essential for preventing S. suis infections in occupational settings.

Farm exposure is associated with human breast milk immune profile and microbiome.

Prenatal and early life farm exposure, and breastfeeding, are associated with protection from allergic diseases. We hypothesize that farm exposure influences the human breast milk microbiome and immune proteins. The immune protein profiles and microbial communities of 152 human breast milk samples were compared among three maternal farm exposure groups (traditional agrarian, farm, and non-farm) in rural Wisconsin to identify signatures associated with farm status and atopic disease. We found significant differences between farm groups for 23 immune proteins (p-adj<0.05), microbiome diversity (p=2.2E-05), and microbiome richness (p=8.0e-06). Traditional agrarian human breast milk had the highest immune protein levels and microbiome diversity and richness, followed by farm and non-farm human breast milk. Furthermore, Gram-positive bacterial species correlated with IL-23 mediated signaling events (p-adj<1.0E-05). These data suggest that increased farm exposures promotes human breast milk that is more microbially-diverse and rich in immune-associated proteins, ultimately influencing immune development in the infant.

Symptom trajectories in infancy for the prediction of subsequent wheeze and asthma in the BILD and PASTURE cohorts: a dynamic network analysis

Host and environment early-life risk factors are associated with progression of wheezing symptoms over time; however, their individual contribution is relatively small. We hypothesised that the dynamic interactions of these factors with an infant's developing respiratory system are the dominant factor for subsequent wheeze and asthma. In this dynamic network analysis we used data from term healthy infants from the Basel-Bern Infant Lung Development (BILD) cohort (435 neonates aged 0-4 weeks recruited in Switzerland between Jan 1, 1999, and Dec 31, 2012) and replicated the findings in the Protection Against Allergy Study in Rural Environments (PASTURE) cohort (498 infants aged 0-12 months recruited in Germany, Switzerland, Austria, France, and Finland between Jan 1, 2002, and Oct 31, 2006). BILD exclusion criteria for the current study were prematurity (<37 weeks), major birth defects, perinatal disease of the neonate, and incomplete follow-up period. PASTURE exclusion criteria were women younger than 18 years, a multiple pregnancy, the sibling of a child was already included in the study, the family intended to move away from the area where the study was conducted, and the family had no telephone connection. Outcome groups were subsequent wheeze, asthma, and healthy. The first outcome was defined as ever wheezed between the age of 2 years and 6 years. Week-by-week correlations of the determining factors with cumulative symptom scores (CSS) were calculated from weeks 2 to 52 (BILD) and weeks 8 to 52 (PASTURE). The complex dynamic interaction between the determining factors and the CSS was assessed via dynamic host-environment correlation network, quantified by a simple descriptor: trajectory function G(t). Wheeze outcomes at age 2-6 years were compared in 335 infants from BILD and 437 infants from PASTURE, and asthma outcomes were analysed at age 6 years in a merged cohort of 783 infants. CSS was significantly different for wheeze and asthma outcomes and became increasingly important during infancy in direct comparison with all determining factors. Weekly symptoms were tracked for groups of infants, showing a non-linear increase with time. Using logistic regression classification, G(t) distinguished between the healthy group and wheeze or asthma groups (area under the curve>0·97, p<0·0001; sensitivity analysis confirmed significant CSS association with wheeze [BILD p=0·0002 and PASTURE p=0·068]) and G(t) was also able to distinguish between the farming and non-farming exposure groups (p<0·0001). Similarly to other risk factors, CSS had weak sensitivity and specificity to identify risks at the individual level. At group level however, the dynamic host-environment correlation network properties (G(t)) showed excellent discriminative ability for identifying groups of infants with subsequent wheeze and asthma. Results from this study are consistent with the 2018 Lancet Commission on asthma, which emphasised the importance of dynamic interactions between risk factors during development and not the risk factors per se. The Swiss National Science Foundation, the Kühne Foundation, the EFRAIM study EU research grant, the FORALLVENT study EU research grant, and the Leibniz Prize.

Associations between acquired antimicrobial resistance genes in the upper respiratory tract and livestock farm exposures: a case-control study in COPD and non-COPD individuals.

Livestock-related emissions have been associated with aggravations of respiratory symptoms in patients with chronic obstructive pulmonary disease (COPD), potentially by altering the respiratory resistome. This study investigates the structure of the acquired oropharyngeal (OP) resistome of patients with COPD and controls, its interplay with the respiratory microbiome and associations with residential livestock exposure. In a matched case-control study in the rural Netherlands, we analysed OP swabs from 35 patients with COPD and 34 controls, none of whom had used antibiotics in the preceding 4 weeks. Resistome profiling was performed using ResCap, complemented by prior characterization of the microbiome via 16S rRNA-based sequencing. Residential livestock farm exposure was defined using distance-based variables alongside modelled concentrations of livestock-emitted microbial pollutants. We compared resistome profiles between patients with COPD and controls, examining alpha and beta diversity as well as differential abundance. Additionally, we assessed the interplay between the resistome and microbiome using co-occurrence networks and Procrustes analysis. Variations in resistome profiles were also analysed based on residential livestock exposures. Patients with COPD exhibited higher resistome diversity than controls (Shannon diversity, P = 0.047), though resistome composition remained similar between groups (PERMANOVA, P = 0.19). Significant correlations were observed between the OP resistome and microbiome compositions, with distinct patterns in co-occurrence networks. Residential exposure to livestock farms was not associated with resistome alterations. Our findings reveal the COPD airway as a hospitable environment for antimicrobial resistance genes, irrespective of recent antimicrobial usage. Demonstrating the interplay between the resistome and microbiome, our study underscores the importance of a deeper understanding of the resistome in respiratory health.

Real-time precision spraying application for tobacco plants

This paper introduces a precision agriculture application aimed at mitigating the excessive utilization of agricultural chemicals, including pesticides and fungicides during crop spraying. The prevailing spraying techniques face two principle challenges: first, the indiscriminate dispensation of chemicals irrespective of plant size and requirements and second, the farmer's exposure to health hazards. To tackle these issues, a detection and segmentation model employing both YOLOv5 and YOLOv6 architectures is proposed and a comparative assessment of their accuracies within the same model category is conducted. The training dataset originates from a subset of the TobSet dataset, while the evaluation of the trained models is executed using publicly accessible aerial videos/images from available repository. The best detection accuracy achieved for the tobacco plant model size is observed with YOLOv6s and the YOLOv5-segmentation model, yielding accuracies of 95% and 94.8%, respectively. Additional performance metrics such as precision, recall, area under the PR-curve, inference time, and NMS per image are also compared between the two models. The YOLOv5-segmentation model excels by outperforming the YOLOv6s model in precision, recall score, and area under the PR-curve whereas slightly extended inference time and NMS per image duration are noted for the YOLOv5-segmentation model and the speed performance is comparable for the two models. Subsequently, the evaluation of these two models is conducted on the drone videos, which were recorded during drone traversal at a speed of 2 km/hr. The results demonstrate superiority of YOLOv5-segmentation model over the YOLOv6s model, with detection accuracies of 98.1% and 97.3%, respectively. These findings indicate the potential of integrating YOLOv5 segmentation models in precision spraying applications and contribute in improving the overall agricultural practices.

RELATIONSHIP BETWEEN PROFILE OF FARMERS AND THEIR PERCEPTION ABOUT ORGANIC FARMING

The study was carried out in Gujarat state. Total 160 farmers practicing organic farming and registered under Gujarat Organic Products Certification Agency were selected randomly for the study. Ex-post facto research design was used. The coefficient of correlation was computed to find out the relationship between the variables and the step-wise regression (multiple regressions) analysis was employed to envisage the extent of variation caused by independent variables on perception towards organic farming. Amongst the sixteen selected variables in the study, education, agricultural mass media exposure, scientific orientation, risk orientation, achievement motivation and knowledge about organic farming had positive and highly significant relationship with the perception of farmers towards organic farming. Out of sixteen independent variables, five variables viz. risk orientation, knowledge about organic farming, cropping intensity, annual income and agricultural mass media exposure were found to be influencing on perception towards organic farming which were together contributing 28.70 per cent variation.

Farming Activities and Risk of Inflammatory Bowel Disease: A French Nationwide Population-based Cohort Study.

Epidemiological data regarding inflammatory bowel disease [IBD] are lacking, in particular for occupationally exposed populations. We investigated whether, among the entire French farm manager [FM] workforce, certain agricultural activities are more strongly associated with IBD than others. Nationwide, population-based, insurance claims and electronic health records from all FMs who worked at least once over the period 2002-2016 were used [n = 1 088 561, 69% males]. The outcome measure was the association between 26 farming activities and the risk of IBD, Crohn's disease [CD], and ulcerative colitis [UC], measured as hazard ratios [HRs], after adjusting for age, sex, pre-existing medical comorbidities, and farm location. The time to first chronic disease declaration was used as the underlying time scale. A model was generated for every activity and disease, using a reference group comprising all FMs who abstained from the specified activity from 2002 to 2016. There were 1752 IBD cases, with 704 CD [40.2%] and 1048 UC [59.8%] cases, respectively. Elevated HRs were observed for fruit arboriculture [HR from 1.17 to 1.52] and dairy farming [HR from 1.22 to 1.46] for all IBD, in crop farming for CD only (HR = 1.26, 95% confidence interval [CI]: 1.06-1.49), and in shellfish farming [HR from 2.12 to 2.51] for both CD and IBD. Further research regarding specific farming activities and exposures likely to modify the microbiota [eg, pesticides, pathogens] is required to identify potential occupational risk factors [agricultural exposome] for IBD. Exposure to Mycobacterium avium subspecies paratuberculosis, Cryptosporidium, environmental toxins, micro/nanoplastics, and pesticides represents promising research avenues.

Farm animal exposure, respiratory illnesses, and nasal cell gene expression

BackgroundFarm exposures in early life reduce the risks for childhood allergic diseases and asthma. There is less information about how farm exposures relate to respiratory illnesses and mucosal immune development. ObjectiveWe hypothesized that children raised in farm environments have a lower incidence of respiratory illnesses over the first two years of life than non-farm children. We also analyzed whether farm exposures or respiratory illnesses were related to patterns of nasal cell gene expression. MethodsThe Wisconsin Infant Study Cohort included farm (n=156) and non-farm (n=155) families with children followed to age 2 years. Parents reported prenatal farm and other environmental exposures. Illness frequency and severity were assessed using illness diaries and periodic surveys. Nasopharyngeal cell gene expression in a subset of 64 children at age two years was compared to farm exposure and respiratory illness history. ResultsFarm vs. non-farm children had nominally lower rates of respiratory illnesses (rate ratio 0.82 [0.69,0.97]) with a stepwise reduction in illness rates in children exposed to 0, 1, or ≥2 animal species, but these trends were non-significant in a multivariable model. Farm exposures and preceding respiratory illnesses were positively related to nasal cell gene signatures for mononuclear cells and innate and antimicrobial responses. ConclusionsMaternal and infant exposure to farms and farm animals was associated with nonsignificant trends for reduced respiratory illnesses. Nasal cell gene expression in a subset of children suggests that farm exposures and respiratory illnesses in early life are associated with distinct patterns of mucosal immune expression.

Occupational farm work activities influence workers’ indoor home microbiome

BackgroundFarm work entails a heterogeneous mixture of exposures that vary considerably across farms and farmers. Farm work is associated with various health outcomes, both adverse and beneficial. One mechanism by which farming exposures can impact health is through the microbiome, including the indoor home environment microbiome. It is unknown how individual occupational exposures shape the microbial composition in workers’ homes. ObjectivesWe investigated associations between farm work activities, including specific tasks and pesticide use, and the indoor microbiome in the homes of 468 male farmers. MethodsParticipants were licensed pesticide applicators, mostly farmers, enrolled in the Agricultural Lung Health Study from 2008 to 2011. Vacuumed dust from participants’ bedrooms underwent whole-genome shotgun sequencing for indoor microbiome assessment. Using questionnaire data, we evaluated 6 farm work tasks (processing of either hay, silage, animal feed, fertilizer, or soy/grains, and cleaning grain bins) and 19 pesticide ingredients currently used in the past year, plus 7 banned persistent pesticide ingredients ever used. ResultsAll 6 work tasks were associated with increased microbial diversity levels, with a positive dose-response for the total number of tasks performed (P = 0.001). All tasks were associated with altered microbial compositions (weighted UniFrac P = 0.001) and with higher abundance of specific microbes, including soil-based commensal microbes such as Haloterrigena. Among the 19 pesticides, current use of glyphosate and past use of lindane were associated with increased microbial diversity (P = 0.02–0.04). Ten currently used pesticides and all 7 banned pesticides were associated with altered microbial composition (P = 0.001–0.04). Six pesticides were associated with differential abundance of certain microbes. DiscussionDifferent farm activities and exposures can uniquely impact the dust microbiome inside homes. Our work suggests that changes to the home microbiome could serve as one pathway for how occupational exposures impact the health of workers and their cohabitating family members, offering possible future intervention targets.

The siren song of cicadas: Early-life pesticide exposure and later-life male mortality

This paper studies the long-term effects of in-utero and early-life exposure to pesticide use on adulthood and old-age longevity. We use the cyclical emergence of cicadas in the eastern half of the United States as a shock that raises the pesticide use among tree crop growing farmlands. We implement a difference-in-difference framework and employ Social Security Administration death records over the years 1975–2005 linked to the complete count 1940 census. We find that males born in top-quartile tree-crop counties and exposed to a cicada event during fetal development and early-life live roughly 2.2 months shorted lives; those with direct farm exposure face a reduction of nearly a year. We provide empirical evidence to examine mortality selection before adulthood, endogenous fertility, and differential data linkage rates. Additional analyses suggests that reductions in education and income during adulthood are potential mechanisms of impact. Our findings add to our understanding of the relevance of early-life insults for old-age health and mortality.

Dairy farming exposure and impacts from coastal flooding and sea level rise in Aotearoa-New Zealand

Globally, episodic coastal flooding is expected to have increasingly severe impacts on agriculture in low-lying coastal areas, as climate change continues to cause relative sea level rise (RSLR). This study analyses dairy farm exposure and impacts from extreme sea levels (ESL) and RSLR in Aotearoa-New Zealand (A-NZ). Spatio-temporal modelling is undertaken using: 1) a dairy production land layer; 2) a static coastal inundation model from 10, 100, 200 and 500-year annual recurrence interval (ARI) ESL events at 0–2 m RSLR (0.5 m increments); and 3) an Impact State (IS) scheme relating percentage of farmland inundated and depth of flooding at milking shed locations to categorise the severity of damage. Through this analysis we highlight the increasing exposure of the dairy industry to coastal flooding, with 472 farms potentially impacted (at or greater than IS 1) by a 10-year ARI event and 1276 farms exposed to a 500-year ARI event at current sea levels, rising to 1276 (10-year ARI) and 1344 farms (500-year ARI) with 2 m RSLR. RSLR is identified as the factor driving this increase in exposure and severity of impacts to dairying, with the increase in the number of farms impacted in a 500-year compared to 10-year event only 5 % greater when considered with 1 m of RSLR, compared to 37 % greater at 0 m RSLR. This has significant implications for A-NZ where the dairy industry is of high economic and social importance, demonstrating the need for industry targeted climate change adaptation and disaster risk reduction measures.

A Case Control Study of Mesoamerican Nephropathy in Farmers with Long-Term Exposure to Agrochemical Compounds in El Salvador

Introduction: Chronic kidney diseases (CKD) are very prevalent in Central America, particularly in El Salvador. Mesoamerican nephropathy (MN) is a CKD diagnosis that mostly affects male agricultural labourers; its aetiology is debatable. Prolonged contact with plague control pesticides is among the possible causes. To determine if there is any association between farming and long-term exposure to such chemical substances and MN in male agricultural labourers, a case control study was performed. Methods: From January 2020–December 2021, the authors gathered a group of 143 male patients with CKD who met the MN criteria, as well as 572 male matched controls with no kidney disease. All were asked about any long-term exposure to agrochemical pesticides, and the odds ratio was calculated. Results: A total of 715 individuals were included. There were 127 cases of MN in individuals who were exposed to agrochemicals and 16 cases in the non-exposed patients. Among the controls, the authors found that 348 had been exposed, while 224 had not. Exposure to pesticides was 5.2 times more likely to be associated with MN compared with individuals with no kidney disease. Conclusion: MN could be a multifactorial disease, where heat stress and dehydration combine with direct long-term exposure to pesticides, causing damage to kidneys’ tubular network and leading to CKD. Further research is needed.

Metagenomics reveals novel microbial signatures of farm exposures in house dust.

Indoor home dust microbial communities, important contributors to human health, are shaped by environmental factors, including farm-related exposures. Advanced metagenomic whole genome shotgun sequencing (WGS) improves detection and characterization of microbiota in the indoor built-environment dust microbiome, compared to conventional 16S rRNA amplicon sequencing (16S). We hypothesized that the improved characterization of indoor dust microbial communities by WGS will enhance detection of exposure-outcome associations. The objective of this study was to identify novel associations of environmental exposures with the dust microbiome from the homes of 781 farmers and farm spouses enrolled in the Agricultural Lung Health Study. We examined various farm-related exposures, including living on a farm, crop versus animal production, and type of animal production, as well as non-farm exposures, including home cleanliness and indoor pets. We assessed the association of the exposures on within-sample alpha diversity and between-sample beta diversity, and the differential abundance of specific microbes by exposure. Results were compared to previous findings using 16S. We found most farm exposures were significantly positively associated with both alpha and beta diversity. Many microbes exhibited differential abundance related to farm exposures, mainly in the phyla Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. The identification of novel differential taxa associated with farming at the genera level, including Rhodococcus, Bifidobacterium, Corynebacterium, and Pseudomonas, was a benefit of WGS compared to 16S. Our findings indicate that characterization of dust microbiota, an important component of the indoor environment relevant to human health, is heavily influenced by sequencing techniques. WGS is a powerful tool to survey the microbial community that provides novel insights on the impact of environmental exposures on indoor dust microbiota. These findings can inform the design of future studies in environmental health.

Assessing farmer's exposure to pesticides and the risk for non-communicable diseases: A biomonitoring study

This cross-sectional study aimed to assess the adverse effects of pesticide use in humans, such as non-communicable diseases, using acetylcholinesterase (AChE) and pesticide concentrations in blood samples. A total of 353 samples (290 case and 63 control) were collected from participants with >20 years of experience in agricultural pesticide use. The pesticide and AChE concentrations were determined using Liquid Chromatography with tandem mass spectrometry (LC-MS/MS) and Reverse Phase High Performance Liquid Chromatography (RP-HPLC). Various health risks from pesticide exposure were assessed, including dizziness or headache, tension, anxiety, confusion, loss of appetite, loss of balance, concentration difficulties, irritability, anger, and depression. These risks may be influenced by the duration and intensity of exposure, the type of pesticide, and environmental factors in the affected areas. A total of 26 pesticides were detected in the blood samples from the exposed population, including 16 insecticides, three fungicides, and seven herbicides. Pesticide concentrations ranged from 0.20 to 12.12 ng/mL, and were statistically significant between the case and control groups (p < 0.05, p < 0.01, and p < 0.001). A correlation analysis was performed to determine statistically significance between pesticide concentration and symptoms of non-communicable diseases, such as Alzheimer's, Parkinson's, obesity, and diabetes. The estimated AChE levels in case and control blood samples were 21.58 ± 2.31 and 24.13 ± 1.08 U/mL, respectively (mean ± SD). The AChE levels were significantly lower in case samples than in controls (p < 0.001), which is considered to be an effect of long-term pesticide exposure, and is the cause of Alzheimer's disease (p < 0.001), Parkinson's disease (p < 0.001), and obesity (p < 0.01). Chronic exposure to pesticides and low levels of AChE are somewhat related to non-communicable diseases.

Obstructive Lung Disease Linked to Occupational Exposures in Malawian Tobacco Farmers

ABSTRACT Nicotine and pesticide exposure in agricultural settings have been linked to the development of chronic respiratory disease in workers. However, this has not been extensively studied in Africa. The aim of this study was therefore to determine the prevalence of obstructive lung disease and its relationship to concurrent nicotine and pesticide exposure among small-scale tobacco farmers in Malawi. For this purpose, sociodemographic characteristics, occupational and environmental exposures were evaluated in relation to work-related respiratory symptoms and lung function impairment. A cross-sectional study was conducted enrolling 279 workers in flue-cured tobacco farms in Zomba, Malawi. The study instruments used for assessing the health outcomes were a standardised European Community Respiratory Health Survey II (ECRHS) questionnaire and Spirometry testing. The questionnaires were aimed at collecting relevant data on sociodemographic factors and self-reported respiratory health outcomes. Data were also collected on potential pesticide and nicotine exposures. Spirometry was done to evaluate objective respiratory impairment in accordance with American Thoracic Society guidelines. The mean age of participants was 38 years with 68% being male. The prevalence of work-related ocular nasal symptoms, chronic bronchitis, and work-related chest symptoms was 20%, 17%, and 29%, respectively. Airflow limitation (FEV1/FVC <70%) was found in 8% of workers. Self-reported exposure to pesticides varied from 72%- to 83%, whilst the prevalence of recent green tobacco sickness was 26%. Tasks linked to nicotine exposure, such as sowing (OR: 2.5; CI 1.1–5.7) and harvesting (OR: 2.6; CI 1.4–5.1), were significantly associated with work-related chest symptoms. Pesticide application (OR:1.96; CI 1.0–3.7) was associated with an increased risk of work-related oculonasal symptoms. Duration of pesticide exposure was also associated with obstructive impairment FEV1/FVC<LLN (OR: 5.11; CI 1.6–16.7) and FEV1/FVC <70% (OR: 4.68; CI 1.2–18.0). This study demonstrated that tobacco farmers in Malawi had a high prevalence of respiratory symptoms and airflow limitation due to obstructive lung disease. This could be attributed to nicotine or pesticide exposure in small-scale tobacco farming. The implementation of occupational health and safety measures to mitigate these exposures may play an important role in modifying the risk of obstructive lung disease in this population.

Farm Exposures and Allergic Disease Among Children Living in a Rural Setting

ABSTRACT Objectives The purpose of this study was to examine the association between farm exposures and asthma and allergic disease in children while also highlighting the experiences of non-farm rural children. Methods This was a cross-sectional analysis of data collected from across the province of Saskatchewan, Canada in 2014. Surveys were completed by parents of 2275 rural dwelling children (farm and non-farm) aged 0 to 17 years within 46 rural schools. Questionnaires were distributed through schools for parents to complete. Results Asthma prevalence was 7.6%, of which 29.5% of cases were allergic. After adjustment for potential confounders, home location (farm vs non-farm) and other farm exposures were not associated with asthma and asthma phenotypes. Those who completed farm safety education were more likely to have asthma (11.7% vs. 6.7%; p = .001) compared to children without asthma. In sub-analyses among 6–12-year-old children, boys were more likely to have asthma (non-allergic) and use short-acting beta-agonists compared to girls. Doing farm work in the summer was associated with an increased risk of asthma [adjusted OR (aOR) = 1.71 (1.02–2.88); p = .041]. Doing routine chores with large animals was associated with an increased risk of asthma [aOR = 1.83 (1.07–3.15); p = .027] and allergic asthma [aOR = 2.37 (95%CI = 1.04–5.40); p = .04]. Conclusion The present study showed that the prevalence of asthma and asthma phenotypes were similar between farm and non-farm rural children. There did not appear to be differential involvement in farming activities between those with and without asthma although those with asthma had more training suggesting possible attempts to mitigate harm from farm exposures.

The impact of the use of personal-protective-equipment on the minimization of effects of exposure to pesticides among farm-workers in India.

Although excessive use of pesticides and unsafe agricultural practices may contribute to numerous intoxications, the role of PPE (personal-protective-equipment) in the minimization of toxicological effects due to pesticide exposure has not been addressed so far. The present study aimed to assess the impact of the use of PPE on the minimization of effects of exposure to pesticides among farm-workers. A community-based follow-up study with questionnaire-based survey and field observations was undertaken among farm-workers (n = 180) of Rangareddy district, Telangana, India. Biomarkers of exposure such as cholinesterase activity, inflammatory markers (TNF-α, IL-1β, IL-6, cortisol, and hs-C reactive protein), nutrients (vitamins A, E), liver function (total protein and A/G ratio, AST and ALT levels) were investigated in the laboratory by following the standard protocols. Farm-workers who had a mean farming exposure of 18 years of and who neither followed safe pesticide handling practices nor used PPE and also showed reluctance to obey good agricultural practices (GAPs). Inhibition of AChE (acetylcholine esterase) with increased inflammation was found among farm-workers as compared to their respective normal values when they have not used PPE. Linear regression statistical analysis revealed a profound effect on inhibition in the AChE activity and various inflammatory markers with the increase in the duration of pesticide exposure. Further, there was no effect of the duration of pesticide exposure on the levels of vitamins A, E, ALT, AST, total protein, and A/G ratio. Further, intervention studies carried out on the use of PPE provided (commercially available and cost-effective) for 90 days showed a significant reduction in the biomarker levels (p < 0.01). This study demonstrated the importance of the use of PPE during pesticide applications and other agricultural tasks to minimize pesticide-associated adverse health effects.

Maternal Human Milk IgA Levels In Two Cohorts With Different Atopic Rates

Prevalence of atopic diseases has been increasing worldwide. However, many studies have indicated that individuals who practice a traditional farming lifestyle have lower rates of allergy. Moreover, studies have shown that maternal farm exposure can confer infant protection as well, possibly through the constitution of their human milk (HM). In this experiment, we measured HM IgA of mothers from the Old Order Mennonites (OOM), who live a traditional farming lifestyle with infants at low-risk of allergy and from mothers living in urban/suburban Rochester (ROC) with high-risk infants.

Early exposure to farm dust in an allergic airway inflammation rabbit model: Does it affect bronchial and cough hyperresponsiveness?

Over the past 50 years, the prevalence of allergic respiratory diseases has been increasing. The Hygiene hypothesis explains this progression by the decrease in the bio-diversity of early microbial exposure. This study aims to evaluate the effect of early-life farm exposure on airway hyperresponsiveness and cough hypersensitivity in an allergic airway inflammation rabbit model. A specific environment was applied to pregnant rabbits and their offspring until six weeks after birth. Rabbits were housed in a pathogen-free zone for the control group and a calf barn for the farm group. At the end of the specific environmental exposure, both groups were then housed in a conventional zone and then sensitized to ovalbumin. Ten days after sensitization, the rabbit pups received ovalbumin aerosols to provoke airway inflammation. Sensitization to ovalbumin was assessed by specific IgE assay. Cough sensitivity was assessed by mechanical stimulation of the trachea, and bronchial reactivity was assessed by methacholine challenge. The farm environment was characterized by endotoxin measurement. A total of 38 rabbit pups were included (18 in the farm group). Endotoxin levels in the farm environment varied from 30 to 1854 EU.m-3. There was no significant difference in specific IgE values to ovalbumin (p = 0.826) between the two groups. The mechanical threshold to elicit a cough did not differ between the two groups (p = 0.492). There was no difference in the number of cough (p = 0.270) or the intensity of ventilatory responses (p = 0.735). After adjusting for age and weight, there was no difference in respiratory resistance before and after methacholine challenge. Early exposure to the calf barn did not affect cough sensitivity or bronchial reactivity in ovalbumin-sensitized rabbits. These results suggest that not all farm environments protect against asthma and atopy. Continuous exposure to several sources of microbial diversity is probably needed.

Cattle farm dust alters cytokine levels in human airway construct model

Epidemiological studies have revealed some alterations in systemic immunity that associate with farm exposure and the risk of respiratory diseases, but in vitro studies focusing on immunological responses in the airways are scarce. Our aim was to assess how cowshed dust affects the integrity and inflammation of human airway tissue in vitro. Cowshed dust samples were collected from four different dairy farms. Lung tissue constructs were exposed to dust samples in air-liquid interface. Transepithelial resistance of the tissue, secreted proteins, and a panel of pro-inflammatory cytokines, growth factors, and chemokines were analysed. Cowshed dust stimulation was associated mainly with increased production of IL-13, IL-15, IP-10 and IFN-γ. Some differences between farms were seen. Only one farm dust sample induced a significant change in transepithelial resistance, whereas dust from two of the farms induced the secretion of proteins. The exposure to cowshed dust affected protein and cytokine secretion, but the response profiles were not uniform between farms. The effect on tight junction dynamics was less pronounced, suggesting the relevance of soluble factors in induced responses in the airways. Our results indicate that in addition to farm type, the contribution of cowshed characteristics to dust composition and its immunomodulatory properties should be taken into account.