Farm Exposure Research Articles

Residential exposure to livestock farms and lung function in adolescence – The PIAMA birth cohort study

BackgroundThere is a growing interest in the impact of air pollution from livestock farming on respiratory health. Studies in adults suggest adverse effects of livestock farm emissions on lung function, but so far, studies involving children and adolescents are lacking. ObjectivesTo study the association of residential proximity to livestock farms and modelled particulate matter ≤10 μm (PM10) from livestock farms with lung function in adolescence. MethodsWe performed a cross-sectional study among 715 participants of the Dutch prospective PIAMA (Prevention and Incidence of Asthma and Mite Allergy) birth cohort study. Relationships of different indicators of residential livestock farming exposure (distance to farms, distance-weighted number of farms, cattle, pigs, poultry, horses and goats within 3 km; modelled atmospheric PM10 concentrations from livestock farms) with forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) at age 16 were assessed by linear regression taking into account potential confounders. Associations were expressed per interquartile range increase in exposure. ResultsHigher exposure to livestock farming was consistently associated with a lower FEV1, but not with FVC among participants living in less urbanized municipalities (<1500 addresses/km2, N = 402). Shorter distances of homes to livestock farms were associated with a 1.4% (0.2%; 2.7%) lower FEV1. Larger numbers of farms within 3 km and higher concentrations of PM10 from livestock farming were associated with a 1.8% (0.8%, 2.9%) and 0.9% (0.4%,1.5%) lower FEV1, respectively. ConclusionsOur findings suggest that higher exposure to livestock farming is associated with a lower FEV1 in adolescents. Replication and more research on the etiologic agents involved in these associations and the underlying mechanisms is needed.

The hygiene hypothesis for allergy - conception and evolution.

In 1989, a short paper entitled "Hay fever, hygiene and household size" observed that British children from larger families were less likely to develop hay fever and suggested that this could be because early exposure to infection prevents allergy. This sibship size association for hay fever, since replicated many times in Britain and other affluent countries and confirmed by objective measures of atopy, prompted what has come to be known as the "hygiene hypothesis for allergy", although that term was not specifically used in the 1989 paper. The present paper reviews the historical roots of the "hygiene hypothesis" and charts its development over more than 30 years. Initial scepticism among immunologists turned to enthusiasm in the mid-1990s as the Th1/Th2 paradigm for allergic sensitisation emerged from animal experiments and the concept of "immunological old friends" became popular from the early 2000s. From the late 1990s, observations of reduced allergy risk among children of anthroposophic families and those brought up on farms suggested that the sibship size effects formed part of a broader range of "hygiene-related" determinants of allergy. Children from large families with farming exposure have approximately sixfold reduction in prevalence of hay fever, indicating the potential strength and epidemiological importance of these environmental determinants. During the 21st century, a wide range of specific microbial, environmental and lifestyle factors have been investigated as possible underlying mechanisms, but sadly none have emerged as robust explanations for the family size and farming effects. Thus, while the "hygiene hypothesis" led to a fundamental reappraisal of our relationship with our microbial environment and to the concept that early exposure, rather than avoidance, is beneficial for developing a healthy immune system, the underlying mechanism for variations in allergy prevalence with family size remains, in Churchillian terms, "a riddle wrapped in a mystery inside an enigma".

Continuous Rather Than Solely Early Farm Exposure Protects From Hay Fever Development

An important window of opportunity for early-life exposures has been proposed for the development of atopic eczema and asthma. However, it is unknown whether hay fever with a peak incidence around late school age to adolescence is similarly determined very early in life. In the Protection against Allergy-Study in Rural Environments (PASTURE) birth cohort potentially relevant exposures such as farm milk consumption and exposure to animal sheds were assessed at multiple time points from infancy to age 10.5 years and classified by repeated measure latent class analyses (n= 769). Fecal samples at ages 2 and 12 months were sequenced by 16S rRNA. Hay fever was defined by parent-reported symptoms and/or physician's diagnosis of hay fever in the last 12 months using questionnaires at 10.5 years. Farm children had half the risk of hay fever at 10.5 years (adjusted odds ratio [aOR] 0.50; 95% CI 0.31-0.79) than that of nonfarm children. Whereas early life events such as gut microbiome richness at 12 months (aOR 0.66; 95% CI 0.46-0.96) and exposure to animal sheds in the first 3 years of life (aOR 0.26; 95% CI 0.06-1.15) were determinants of hay fever, the continuous consumption of farm milk from infancy up to school age was necessary to exert the protective effect (aOR 0.35; 95% CI 0.17-0.72). While early life events determine the risk of subsequent hay fever, continuous exposure is necessary to achieve protection. These findings argue against the notion that only early life exposures set long-lasting trajectories.

Early-life farm exposures and eczema among adults in the Agricultural Lung Health Study.

Several studies conducted in Europe have suggested a protective association between early-life farming exposures and childhood eczema or atopic dermatitis; few studies have examined associations in adults. To investigate associations between early-life exposures and eczema among 3217 adult farmers and farm spouses (mean age 62.8 years) in a case-control study nested within an US agricultural cohort. We used sampling-weighted logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (95%CIs) for associations between early-life exposures and self-reported doctor-diagnosed eczema (273 cases) and polytomous logistic regression to estimate ORs (95%CIs) for a 4-level outcome combining information on eczema and atopy (specific IgE≥0.35). Additionally, we explored genetic and gene-environment associations with eczema. Although early-life farming exposures were not associated with eczema overall, several early-life exposures were associated with a reduced risk of having both eczema and atopy. Notably, results suggest stronger protective associations among individuals with both eczema and atopy than among those with either atopy alone or eczema alone. For example, ORs (95%CIs) for having a mother who did farm work while pregnant were 1.01 (0.60-1.69) for eczema alone and 0.80 (0.65-0.99) for atopy alone, but 0.54 (0.33-0.80) for having both eczema and atopy. A genetic risk score based on previously identified atopic dermatitis variants was strongly positively associated with eczema, and interaction testing suggested protective effects of several early-life farming exposures only in individuals at lower genetic risk. In utero and childhood farming exposures are associated with decreased odds of having eczema with atopy in adults.

Prevalence and Characteristics of Chronic Obstructive Pulmonary Disease in Dairy Farmers

Objective: To assess the prevalence and characteristics of chronic obstructive pulmonary disease (COPD) in dairy farmers, and evaluate the role of job exposure and smoking as predictors for respiratory health impairment. Methods: A cross-sectional study was performed, including 83 dairy farmers (mean age: 52.6±8.7 years; mean exposure duration: 23.7±7.6 years) and 80 office workers as a control group (mean age: 52.7±8.2 years) matched for age, smoking habits, and socioeconomic status. Methods for evaluation of study participants included a questionnaire on respiratory symptoms in the last 12 months, baseline spirometry and bronchodilator reversibility testing, and diagnostic criteria for COPD. Results: The mean post-bronchodilator values of spirometric parameters are significantly lower in subjects among EG with negative bronchodilator test compared to those in CG, while the mean post-bronchodilator values of spirometric parameters are lower in dairy farmers with negative BD tests exposed more than 20 years compared to those with exposure less than 20 years, being statistically significant for FEV1/FVC%, MEF25, MEF50 and MEF75. The COPD prevalence is non-significantly higher in dairy farmers compared to controls, and is significantly associated with age over 40 years in dairy farmers (P=0.035). The risk for COPD development in dairy farmers is about 36 fold higher in subjects exposed more than 20 years (OR = 36.00 (1.21-37.77) CI 95%) compared to those with exposure duration less than 20 years, and is about 6 fold higher in dairy farmers who are current smokers (OR = 6.12 (0.95-37.77) CI 95%). COPD is significantly associated with smoking duration among smokers in both groups, while combined effect of smoking, smoking duration, and number of cigarettes smoked daily has a significant impact on COPD development in dairy farmers. According to the GOLD classification, depending on the degree of airflow limitation, mild and moderate types of COPD are detected in dairy farmers, and only mild type in controls, showing no significant difference between the two groups. Conclusion: The study findings recognized the role of farming exposure, and smoking as well, as predictors for respiratory health impairment, and furthermore confirmed their potential to be a predictive factor in the COPD development. These facts should be helpful in detection of critical points for action, indicate the need of adverse occupational exposures reduction through adequate preventive measures and regular health examinations, implementation of relevant engineering controls, smoking cessation programs, and complete and efficient respiratory health assessment.

Exploring the Relationship between Hog Farm Exposure and Chronic Obstructive Pulmonary Disease (COPD)

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) and related conditions continue to be a major public health concern. The primary cause of COPD is cigarette smoking; however, other risk factors include air pollution, work environment, infectious diseases and genetic predispositions. Related human studies have suggested that air quality and environment surrounding hog farms, specifically within low-middle income counties, have the potential to induce lung dysfunction. AIM: The aim of this study is to explore the relationship between hog farming practices and chronic obstructive pulmonary disease . METHODS: Geographical Information Software (GIS) was used to determine the association between state-wide hog farm location density and COPD. A retrospective (2000-2016) partial ecological study of 14 major Arkansas hog farm cities was conducted using the International Classification Code of Diseases- 10. Seven case cities (as those containing a hog farm) and seven control cities (as those without a hog farm) were identified. RESULTS: Hog farm density was positively correlated with state-wide COPD prevalence and low median income. Further analysis, after controlling for county level race, gender, ethnicity, establishment year, alcohol abuse, drug abuse, smoking, obesity, and chronic neurological conditions, resulted in a protective association between hog farm exposure and COPD 0.78 (0.734, 0.840). CONCLUSIONS: Given the study&amp;#x27;s results, city-wide hog farm exposure is not positively associated with county-level COPD prevalence. However, farm location density was determined to be correlated with state-wide COPD prevalence and low median income. A follow-up study using individual data, should be conducted to provide further insight in this exposure, outcome relationship. KEYWORDS: FARMING COPD CHEMICALS RESPIRATORY LUNG

Allergic and non-allergic wheeze among farm women in the Agricultural Health Study (2005–2010)

BackgroundFarms represent complex environments for respiratory exposures including hays, grains and pesticides. Little is known about the impact of these exposures on women’s respiratory health. We evaluated the association of...

Biomarkers of Development of Immunity and Allergic Diseases in Farming and Non-farming Lifestyle Infants: Design, Methods and 1 Year Outcomes in the "Zooming in to Old Order Mennonites" Birth Cohort Study.

Traditional farming lifestyle has been shown to be protective against asthma and allergic diseases. The individual factors that appear to be associated with this “farm-life effect” include consumption of unpasteurized farm milk and exposure to farm animals and stables. However, the biomarkers of the protective immunity and those associated with early development of allergic diseases in infancy remain unclear. The “Zooming in to Old Order Mennonites (ZOOM)” study was designed to assess the differences in the lifestyle and the development of the microbiome, systemic and mucosal immunity between infants born to traditional farming lifestyle at low risk for allergic diseases and those born to urban/suburban atopic families with a high risk for allergic diseases in order to identify biomarkers of development of allergic diseases in infancy. 190 mothers and their infants born to Old Order Mennonite population protected from or in Rochester families at high risk for allergic diseases were recruited before birth from the Finger Lakes Region of New York State. Questionnaires and samples are collected from mothers during pregnancy and after delivery and from infants at birth and at 1–2 weeks, 6 weeks, 6, 12, 18, and 24 months, with 3-, 4-, and 5-year follow-up ongoing. Samples collected include maternal blood, stool, saliva, nasal and skin swabs and urine during pregnancy; breast milk postnatally; infant blood, stool, saliva, nasal and skin swabs. Signs and symptoms of allergic diseases are assessed at every visit and serum specific IgE is measured at 1 and 2 years of age. Allergic diseases are diagnosed by clinical history, exam, and sensitization by skin prick test and/or serum specific IgE. By the end of the first year of life, the prevalence of food allergy and atopic dermatitis were higher in ROC infants compared to the rates observed in OOM infants as was the number of infants sensitized to foods. These studies of immune system development in a population protected from and in those at risk for allergic diseases will provide critical new knowledge about the development of the mucosal and systemic immunity and lay the groundwork for future studies of prevention of allergic diseases.

Exposure of Smart Farming Implementation Towards Farmers in Alor Setar: A Case Study

Smart farming is a trend in agriculture that involves incorporating information and communication technologies (ICT) into the production process. The study aims to get the factors that contribute to the current exposure to smart farming implementation on farmers from farmers’ perspectives in Alor Setar, Kedah, Malaysia. The study includes the determination of correlation between factors and exposure implementation of smart farming. About 116 farmers have been selected from the population to conduct the questionnaire. The results were obtained by analysing using Statistical Package for the Social Science (SPSS) software. It has been found that personal factors contribute the most to the exposure of smart farming implementation. A significant correlation between personal and environmental factors also has been discovered. Contrary, the security factors have no significant correlation with the exposure of smart farming implementation. Overall, the findings indicated that the implementation of smart farming exposure among farmers is emerging progressively.

Farm living and allergic rhinitis from childhood to young adulthood: Prospective results of the GABRIEL study

Growing up on a farm is associated with a reduced prevalence of respiratory allergies in childhood. Whether this protective effect remains into adulthood is unknown. We aimed to prospectively investigate the relationship between farm exposure and prevalence of allergic rhinitis and wheeze from childhood to early adulthood. Participants from phase 2 of the Multidisciplinary Study to Identify the Genetic and Environmental Causes of Asthma in the European Community (GABRIEL) who were living in southern Germany (aged 6-11 years at baseline and 20-25 years at follow-up) were invited to complete a questionnaire on sociodemographic data, farm contact, respiratory symptoms, and potential confounders. Odds ratios (ORs) with 95% CIs were modeled by using generalized estimating equations. Of the 2276 phase 2 participants, 1501 (66%) answered the follow-up questionnaire, of whom 1333 could be included in the analyses. Living on a farm was associated with reduced prevalence of allergic rhinitis (OR with persistent farm living=0.4 [95% CI= 0.2-0.6]; OR with farm living at baseline only= 0.4 [95% CI= 0.2-0.8]). The OR for development of symptoms from baseline to follow-up was almost 3 (OR= 2.7 [95% CI= 2.1-3.3]) irrespective of farm living. For symptoms of wheeze, no statistically significant association with farm living was observed. The protective effect of farm living on allergic rhinitis persists from childhood to early adulthood. Continuing exposure over puberty does not add to the effect. This confirms that the window of opportunity for a protective effect might be found in childhood.

Insect and Pest Detection in Stored Grains: Analysis of Environmental Factors and Comparison of Deep Learning Methods

Majority of the world’s population depends on agro-based economy for their income and survival. In developing and under-developed countries, due to reasons like basic farming techniques, less educational and technological exposure, lack of technological advancements and recent agricultural knowledge, yield of the crops is very low and moreover there is a huge loss during storage also. Insects, pests and diseases more often affect the stored grains and cause heavy damage to the quantity and quality of the grains. Insecticides and pesticides cannot provide better solution all the times and hence there is an acute need for computer vision based techniques capable of monitoring the spread of insects in the initial stages of storage and protecting the stored grains from further damages and losses. Hence, this paper provides analysis of various factors which can cause damage to the stored grains natural ways to protect crops. It provides the comparison results of various standard deep learning methods that are used to detect the insects and pests in stored grains.

Using genomic epidemiology of SARS-CoV-2 to support contact tracing and public health surveillance in rural Humboldt County, California

BackgroundDuring the COVID-19 pandemic within the United States, much of the responsibility for diagnostic testing and epidemiologic response has relied on the action of county-level departments of public health. Here we describe the integration of genomic surveillance into epidemiologic response within Humboldt County, a rural county in northwest California.MethodsThrough a collaborative effort, 853 whole SARS-CoV-2 genomes were generated, representing ~58% of the 1,449 SARS-CoV-2-positive cases detected in Humboldt County as of March 12, 2021. Phylogenetic analysis of these data was used to develop a comprehensive understanding of SARS-CoV-2 introductions to the county and to support contact tracing and epidemiologic investigations of all large outbreaks in the county.ResultsIn the case of an outbreak on a commercial farm, viral genomic data were used to validate reported epidemiologic links and link additional cases within the community who did not report a farm exposure to the outbreak. During a separate outbreak within a skilled nursing facility, genomic surveillance data were used to rule out the putative index case, detect the emergence of an independent Spike:N501Y substitution, and verify that the outbreak had been brought under control.ConclusionsThese use cases demonstrate how developing genomic surveillance capacity within local public health departments can support timely and responsive deployment of genomic epidemiology for surveillance and outbreak response based on local needs and priorities.

Pesticide use and risk of systemic autoimmune diseases in the Agricultural Health Study

BackgroundSystemic lupus erythematosus (SLE) risk has been associated with pesticide use, but evidence on specific pesticides or other agricultural exposures is lacking. We investigated history of pesticide use and risk of SLE and a related disease, Sjögren's syndrome (SS), in the Agricultural Health Study. MethodsThe study sample (N = 54,419, 52% male, enrolled in 1993–1997) included licensed pesticide applicators from North Carolina and Iowa and spouses who completed any of the follow-up questionnaires (1999–2003, 2005–2010, 2013–2015). Self-reported cases were confirmed by medical records or medication use (total: 107 incident SLE or SS, 79% female). We examined ever use of 31 pesticides and farm tasks and exposures reported at enrollment in association with SLE/SS, using Cox regression to estimate hazard ratios (HR) and 95% confidence intervals (CI), with age as the timescale and adjusting for gender, state, and correlated pesticides. ResultsIn older participants (>62 years), SLE/SS was associated with ever use of the herbicide metribuzin (HR 5.33; 95%CI 2.19, 12.96) and applying pesticides 20+ days per year (2.97; 1.20, 7.33). Inverse associations were seen for petroleum oil/distillates (0.39; 0.18, 0.87) and the insecticide carbaryl (0.56; 0.36, 0.87). SLE/SS was inversely associated with having a childhood farm residence (0.59; 0.39, 0.91), but was not associated with other farm tasks/exposures (except welding, HR 2.65; 95%CI 0.96, 7.35). ConclusionsThese findings suggest that some agricultural pesticides may be associated with higher or lower risk of SLE/SS. However, the overall risk associated with farming appears complex, involving other factors and childhood exposures.

Farm exposure and rates of early life respiratory illness and wheeze

Early childhood exposure to animal farming environments has been associated with decreased incidence of allergy and asthma. We hypothesize that children raised in Wisconsin farm environments will have a lower incidence of viral wheeze in the first two years of life.

Molecular epidemiology of Japanese encephalitis in pigs and risk factors associated with causing Japanese encephalitis in pigs of Lakhimpur, the first case reported in the district of North East India.

Japanese encephalitis (JE) is a major public health problem in India. The first outbreaks of JE have been reported from the North-eastern regions of Assam, particularly from the Lakhimpur district of Assam between July-August 1989. In Assam every year many people died due to JE. This study was performed to investigate the molecular epidemiology of JE in pigs in Lakhimpur district of Assam and the risk factors associated with causing Japanese encephalitis in pigs. This study will help to map out the endemic regions and to know where and when to apply the most control strategies towards the prevention and control of the disease. A total of 342 serum samples from pigs were collected from 10 organized and 20 unorganized farms from 9 blocks and recorded to age, sex and breed and tested by RT-PCR. Pig farms and the surrounding environment were studied for assessment of farm-level risk factors responsible for JEV infection in pigs. Out of 342 samples tested for detection of the E gene of JEV, 14 samples were found to be positive with a prevalence rate of 4.09%. Age, sex and breed-wise higher cases were found in at the age group above 12 months, sex wise female and breed-wise local pigs. Pig farms less than 500 meters from risk factors like rice field, stagnant water source, wild bird exposure to farm and mosquito exposure at farm/ bite to pigs, found to be more numbers of JE cases. Molecular epidemiology of JE in pigs, and humans; positive at Lakhimpur recommend the need for uninterrupted surveillance of this virus in pigs specially those areas where pig population is more and all risk factors are present.

Use of Antibiotics among Residents Living Close to Poultry or Goat Farms: A Nationwide Analysis in The Netherlands.

Prior regional studies found a high risk of pneumonia for people living close to poultry and goat farms. This epidemiological study in the Netherlands used nationwide antibiotic prescription data as a proxy for pneumonia incidence to investigate whether residents of areas with poultry and goat farms use relatively more antibiotics compared to areas without such farms. We used prescription data on antibiotics most commonly prescribed to treat pneumonia in adults and livestock farming data, both with nationwide coverage. Antibiotic use was expressed as defined daily doses per (4-digit Postal Code (PC4) area)-(age group)-(gender)-(month) combination for the year 2015. We assessed the associations between antibiotic use and farm exposure using negative binomial regression. The amoxicillin, doxycycline, and co-amoxiclav use was significantly higher (5–10% difference in use) in PC4 areas with poultry farms present compared to areas without, even after adjusting for age, gender, smoking, socio-economic status, and goat farm presence. The adjusted models showed no associations between antibiotic use and goat farm presence. The variables included in this study could only partly explain the observed regional differences in antibiotic use. This was an ecological study that precludes inference about causal relations. Further research using individual-level data is recommended.

Adaptation Implications of Climate-Smart Agriculture in Rural Pakistan

In this paper, we analyze the drivers of the adoption of climate-smart agricultural (CSA) practices and the impact of their adoption on farm net returns and exposure to risks. We use recent farm-level data from three agroecological zones of Pakistan to estimate a multinomial endogenous switching regression for different CSA practices used to reduce the adverse impact of climate change. These strategies include changing input mix, changing cropping calendar, diversifying seed variety, and soil and water conservation measures. The empirical results show that the adoption of different CSA practices is influenced by average rainfall, previous experience of climate-related shocks, and access to climate change information. The findings further reveal that adoption of CSA practices positively and significantly improves farm net returns and reduces farmers’ exposure to downside risks and crop failure. The results also reveal significant differences in the impacts of CSA practice adoption on farm net returns in different agroecological zones. Thus, policies aimed at achieving sustainability in agricultural production should consider agroecological, specific, climate-smart solutions.

Traditional Farming Lifestyle in Old Older Mennonites Modulates Human Milk Composition.

BackgroundIn addition to farming exposures in childhood, maternal farming exposures provide strong protection against allergic disease in their children; however, the effect of farming lifestyle on human milk (HM) composition is unknown.ObjectiveThis study aims to characterize the maternal immune effects of Old Order Mennonite (OOM) traditional farming lifestyle when compared with Rochester (ROC) families at higher risk for asthma and allergic diseases using HM as a proxy.MethodsHM samples collected at median 2 months of lactation from 52 OOM and 29 ROC mothers were assayed for IgA1 and IgA2 antibodies, cytokines, endotoxin, HM oligosaccharides (HMOs), and targeted fatty acid (FA) metabolites. Development of early childhood atopic diseases in children by 3 years of age was assessed. In addition to group comparisons, systems level network analysis was performed to identify communities of multiple HM factors in ROC and OOM lifestyle.ResultsHM contains IgA1 and IgA2 antibodies broadly recognizing food, inhalant, and bacterial antigens. OOM HM has significantly higher levels of IgA to peanut, ovalbumin, dust mites, and Streptococcus equii as well TGF-β2, and IFN-λ3. A strong correlation occurred between maternal antibiotic use and levels of several HMOs. Path-based analysis of HMOs shows lower activity in the path involving lactoneohexaose (LNH) in the OOM as well as higher levels of lacto-N-neotetraose (LNnT) and two long-chain FAs C-18OH (stearic acid) and C-23OH (tricosanoic acid) compared with Rochester HM. OOM and Rochester milk formed five different clusters, e.g., butyrate production was associated with Prevotellaceae, Veillonellaceae, and Micrococcaceae cluster. Development of atopic disease in early childhood was more common in Rochester and associated with lower levels of total IgA, IgA2 to dust mite, as well as of TSLP.ConclusionTraditional, agrarian lifestyle, and antibiotic use are strong regulators of maternally derived immune and metabolic factors, which may have downstream implications for postnatal developmental programming of infant’s gut microbiome and immune system.

Effect of cattle farm exposure on oropharyngeal and gut microbial communities and antibiotic resistance genes in workers

Livestock farms are recognized as the main sources of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) with potential implications for human health. In this study, we systematically analyzed microbiome composition, distribution of ARGs and mobile genetic elements (MGEs) in the oropharynx and gut of workers in cattle farms and surrounding villagers, cattle feces and farm air, and the relationship of microbial communities among farm air, cattle feces and farmworkers (oropharynx and gut). Exposure to the farm environment may have remodeled farmworkers' oropharynx and gut microbiota, with reduced microbial diversity (P < 0.05) and enrichment of some opportunistic pathogenic bacteria like Shigella, Streptococcus, and Neisseria in the oropharynx. Meanwhile, compared with villagers, ARG abundance in oropharynx of farmworkers increased significantly (P < 0.05), but, no significant difference in gut (P > 0.05). Microbial composition and ARG profile in farmworkers might be influenced by working time and work type, ARG abundance in farmworkers' gut was positively correlated with working time (P < 0.01), and higher ARG abundance was found in the oropharynx of drovers. The network analysis revealed that 4 MGEs (tnpA-01, tnpA-04, Tp614, and IS613), 5 phyla (e.g. Bacteroidetes, Fusobacteria, and TM7), and 6 genera were significantly associated with 37 ARGs (ρ > 0.6, P < 0.01). Overall, our results indicated that farm exposure may have affected the microbial composition and increased ARG abundance of farmworkers. Transmission of some ARGs may have occurred among the environment, animals and humans via host bacteria, which might pose a potential threat to human health.

Occupational Exposure and Multiple Myeloma Risk: An Updated Review of Meta-Analyses.

The precise etiology of multiple myeloma remains elusive, but both genetic and environmental factors have been suggested to contribute to disease risk. Several occupational categories and toxic agents have been implicated as potentially causative, yet findings from the literature are inconsistent. The aim of this review was to summarize and critically comment on the accumulated epidemiological evidence, across published meta-analyses, about the association between occupational exposure and risk of multiple myeloma. Overall, results from eleven meta-epidemiological studies underscore a significantly increased risk for firefighters, hairdressers, and employees exposed to engine exhaust, whereas farming and methylene chloride exposure have been non-significantly correlated with the disease. Further epidemiological studies are of utmost importance whilst emphasis should be placed on occupational hazard surveillance, as such studies will obtain a more accurate picture of disease occurrence in working populations, and will enable both the implementation of preventive actions and the evaluation of their effectiveness.