A global perspective on the influence of environmental exposures on the nervous system.

Economic transitions in the era of globalization warrant a fresh look at the neurological risks associated with environmental change. These are driven by industrial expansion, transfer and mobility of goods, climate change and population growth. In these contexts, risk of infectious and non-infectious diseases are shared across geographical boundaries. In low- and middle-income countries, the risk of environmentally mediated brain disease is augmented several fold by lack of infrastructure, poor health and safety regulations, and limited measures for environmental protection. Neurological disorders may occur as a result of direct exposure to chemical and/or non-chemical stressors, including but not limited to, ultrafine particulate matters. Individual susceptibilities to exposure-related diseases are modified by genetic, epigenetic and metagenomic factors. The existence of several uniquely exposed populations, including those in the areas surrounding the Niger Delta or north western Amazon oil operations; those working in poorly regulated environments, such as artisanal mining industries; or those, mostly in sub-Saharan Africa, relying on cassava as a staple food, offers invaluable opportunities to advance the current understanding of brain responses to environmental challenges. Increased awareness of the brain disorders that are prevalent in low- and middle-income countries and investments in capacity for further environmental health-related research are positive steps towards improving human health.

Evaluation of occupational pesticide exposure on Egyptian male adolescent cognitive and motor functioning.

BACKGROUND: Chronic low-level exposure to organophosphorus pesticides is associated with adverse health effects, including a decline in neurological functioning and long-term impairment. These negative effects may be more detrimental in children and adolescents due to their critical stage in development. Little work has investigated the effects of chronic exposure to pesticides, specifically chlorpyrifos (CPF) during the adolescent period. OBJECTIVES: To examine effects of CPF exposure over a year-long period within a group of male adolescents in Egypt (N = 242, mean age = 17.36), including both pesticide applicators and non-applicators. METHODS: Associations between average CPF exposure (measured via urinary metabolite levels of 3,5,6-trichloro-2-pyridinol [TCPy]) and neurobehavioral functioning were examined in a 1-year longitudinal study. Given previous literature, higher levels of TCPy were expected to be associated with worse neurobehavioral functioning. RESULTS: Using mixed effects linear regression, average TCPy exposure predicted deficits in more complex neurobehavioral tasks (Benton visual retention, digit span reverse, match to sample, serial digit learning, and alternating tapping) with estimates of effects ranging from -0.049 to 0.031. Age (effects ranging from 0.033 to 0.090) and field station (effects ranging from -1.266 to -0.278) were significantly predictive of neurobehavioral functioning over time. An interaction effect was found for field station and TCPy across several neurobehavioral domains. DISCUSSION: Results show that occupational exposure to pesticides may have particularly deleterious effects on complex neurobehavioral domains. Additionally, differences across field stations and the age at which individuals are exposed may be important factors to investigate in future research.

Risk perception and behavior in Egyptian adolescent pesticide applicators: an intervention study.

BACKGROUND: Adolescents are engaged in agricultural work, including pesticide application, around the world. Adolescent pesticide applicators are more likely to be exposed to pesticides than their adult counterparts because of their application practice and hygiene habits surrounding pesticide use. There is a need for low-cost interventions to reduce pesticide exposure. We evaluated a theoretically-based educational intervention to change perceptions about the risk of pesticide use and hygiene habits during and after pesticide application for adolescent and young adult pesticide applicators in Egypt. METHODS: Young adult and adolescent male pesticide applicators were given a one-hour educational intervention to inform them about the risk of pesticide use and how to reduce pesticide exposure. The median age of participants was 18 years old. Changes in perceived susceptibility and effectiveness were measured with a survey pre and post-intervention (n = 119) on the same day. The same survey (n = 95) was given 8-months post-intervention to identify sustained effects. Observational checklists of pesticide application practice were also completed during application seasons before and after the intervention. RESULTS: There was an increase in the proportion of individuals who viewed pesticides as being a long-term health risk (74.7% pre-intervention to 97.9% post-intervention, McNemar test p < 0.001). This change remained significant when surveyed at the 8-month follow-up (90.5%, p < 0.001). There was also a sustained improvement regarding participants' views of proper hygiene practice surrounding pesticide application. Applicators were observed wearing goggles, shoes, and masks more frequently post-intervention. CONCLUSION: This theoretically-based intervention is an example of a low-cost solution that can improve adolescents' and young adults' practices regarding pesticide application and personal hygiene practices during and after pesticide application. The intervention can be applied in other countries with similar safety culture surrounding pesticide application.

Chronic kidney diseases in agricultural communities: report from a workshop.

In June 2018, the National Institute of Diabetes and Digestive and Kidney Diseases and the National Institute of Environmental Health Sciences sponsored a workshop to identify research gaps in an increasingly common form of chronic kidney disease in agricultural communities, often termed "CKDu." The organizers invited a broad range of experts who provided diverse expertise and perspectives, many of whom had never addressed this particular epidemic. Discussion was focused around selected topics, including identifying and mitigating barriers to research in CKDu, creating a case definition, and defining common data elements. All hypotheses regarding etiology were entertained, and meeting participants discussed potential research strategies, choices in study design, and novel tools that may prove useful in this disease. Achievements of the workshop included robust cross-disciplinary discussion and preliminary planning of research goals and design. Specific challenges in implementing basic and clinical research and interventions in low- and middle-income countries were recognized. A balanced approach to leveraging local resources and capacity building without overreaching was emphasized.

Deepwater Horizon oil spill exposures and neurobehavioral function in GuLF study participants.

INTRODUCTION: The 2010 Deepwater Horizon (DWH) disaster exposed tens of thousands of oil spill response and cleanup (OSRC) workers to hydrocarbons and other hazardous chemicals. Some hydrocarbons, such as toluene and hexane, have been found to have acute adverse effects on the central nervous system in occupational settings. However, no studies have examined the association between oil spill exposures and neurobehavioral function. METHODS: We used data from the Gulf Long-term Follow-up Study, a cohort of adults who worked on the DWH response and cleanup. Total hydrocarbon (THC) exposure attributed to oil spill cleanup work was estimated from a job-exposure matrix linking air measurement data to detailed cleanup work histories. Participants were also categorized into 6 job categories, or OSRC classes, based on their activity with the highest exposure. Neurobehavioral performance was assessed at a clinical exam 4-6 years after the spill. We used multivariable linear regression to evaluate relationships of ordinal THC levels and OSRC classes with 16 neurobehavioral outcomes. RESULTS: We found limited evidence of associations between THC levels or OSRC classes and decreased neurobehavioral function, including attention, memory, and executive function. Workers exposed to ≥3 ppm THC scored significantly worse (difference1.0-2.9ppm = -0.39, 95% confidence interval (CI) = -0.74, -0.04) than workers exposed to <0.30 ppm THC for the digit span forward count test. There was also a possible threshold effect above 1 ppm THC for symbol digit test total errors (difference1.0-2.9ppm = -0.56 (95% CI = -1.13, -0.003), difference≥3.0ppm = -0.55 (95% CI = -1.20, 0.10)). Associations appeared to be stronger in men than in women. A summary latency measure suggested an association between more highly exposed jobs (especially support of operations workers) and decreased neurobehavioral function. CONCLUSION: OSRC-related exposures were associated with modest decreases in neurobehavioral function, especially attention, memory, and executive function.

More than time and money: A mixed-methods study of the barriers to safer cattle handling practices.

BACKGROUND: Cattle are responsible for more injuries and fatalities than any farm animal, and cattle-related nonfatal injuries are some of the costliest, requiring more time off work than other injuries. Though research has improved our understanding of cattle behavior, developed low-stress handling practices, and determined how facilities can be safer, injury rates remain high. This project identified the types of equipment commonly used on farms and assessed farmer perceptions of safety and barriers to implementing changes. METHODS: A mixed-methods design was used for this study. The study was comprised of a survey (N = 66) and four site visits conducted at operations focusing on different types of beef production in Iowa, United States. Information collected included descriptive characteristics of the operator and operation, tasks carried out on the farm, handling facility components and design, and incidents of handling-related injuries. RESULTS: Most farms indicated that they utilized equipment like alleyways, a manual headgate, a sorting/diverter gate, and a manual squeeze chute. Farmers cited the cost of equipment, lack of necessity (their setup worked well already), and lack of time as being the main reasons they have not implemented changes in their operations. However, qualitative responses provided additional details and nuance, illuminating farmers' anxieties related to farm transitions, knowledge, and trust of equipment sales personnel. CONCLUSION: This study provides health and safety professionals with additional details about why beef cattle producers may choose not to invest in safer handling equipment, even when they recognize the safety benefits of doing so.

Efficacy of technology-based interventions to increase the use of hearing protections among adolescent farmworkers.

OBJECTIVE: Adolescent farmworkers are exposed to loud noise during farm activities. We present a prospective study that evaluated the efficacy of low-cost, technology-based intervention approaches in high schools to enhance the use of hearing protection among adolescent farmworkers. DESIGN: Six high schools in Iowa that agreed to participate in the study were divided into three equal groups through cluster-randomisation with each group receiving one of the three formats of hearing protection intervention: (a) classroom training, (b) classroom training coupled with smartphone app training and (c) computer training. Participants completed baseline (pre-training) and six-week post-intervention surveys for assessing hearing protection knowledge, attitudes and behaviour. STUDY SAMPLE: Seventy participants from six schools were initially enrolled but 50 completed both pre- and post-intervention surveys. RESULTS: In most cases, all three groups showed significant improvement in hearing protection knowledge, attitude and frequency of use from pre- to post-intervention. However, changes between groups were statistically non-significant. CONCLUSIONS: Although all three formats led to improvements on hearing protection knowledge, attitude and behaviour, the findings of the study, perhaps due to the small sample size, did not allow us to detect whether technology-based hearing protection interventions were more effective than the traditional face-to-face training for adolescent farmworkers.

Organophosphorus pesticide residue levels in homes located near orchards.

Organophosphorus pesticides (OPs) are commonly applied to agricultural crops. Families living in these communities may have higher exposure to OPs due to take home exposures and close proximity to agricultural fields. The objectives of this study were to measure OP concentrations in home carpet dust in agricultural and non-agricultural households and examine factors that may impact OP concentrations such as occupation, housing characteristics, and resident behaviors. Agricultural households had at least one parent who worked in agriculture during the previous 5 years. Carpet dust samples were collected at two time points from 278 households in an agricultural community located in the Pacific Northwest from 2008-2011. Samples were analyzed for four types of OPs: azinphos-methyl, phosmet, malathion, and chlorpyrifos. Overall, OP detection frequencies and concentrations were higher in agricultural households compared to non-agricultural households. Factors associated with higher OP concentrations in home carpet dust were identified and included: (1) homes with two or more agricultural workers living in the home, (2) homes located in close proximity to an agricultural field or orchard, (3) having an entry floor mat, and (4) frequently vacuuming the house. Having air conditioning in the home had a protective effect with OP concentrations. While the use of these four OPs is restricted or limited for residential use in the United States, results show that they were still found in the indoor environment. The understanding of the impact of agricultural work and other factors that elevate levels of OPs in the home is crucial to mitigating pesticide exposure in agricultural communities.

The impact of repeated organophosphorus pesticide exposure on biomarkers and neurobehavioral outcomes among adolescent pesticide applicators.

Egyptian adolescents are hired as seasonal workers to apply pesticides to the cotton crop and may perform this occupation for several years. However, few studies examined the effects of repeated pesticide exposure on health outcomes The goal of this study was to determine the impact of repeated pesticide exposure on neurobehavioral (NB) performance and biomarkers of exposure (urinary metabolite) and effect (cholinesterase activity). Eighty-four adolescents from two field stations in Menoufia, Egypt, were examined four times: before and during pesticide application season in 2010 and again before and during application season in 2011. At each of the four time points, participants completed a questionnaire, performed an NB test battery, and were assessed for urinary levels of the chlorpyrifos metabolite TCPy (3,5,6-trichloro-2-pyridinol) and blood cholinesterase activity. Following the study cohort over two consecutive pesticide application seasons revealed that TCPy levels significantly increased following exposure, and returned to baseline levels following the end of the application season. Blood butyryl cholinesterase activity exhibited a similar pattern. Although NB outcomes displayed learning and practice effects over time, deficits in performance were significantly associated with increased TCPy levels with reduction in the number of NB measures showing improvement over time. Biomarkers of exposure and effect demonstrated changes associated with pesticide application and recovery after application ended. Deficits in NB performance were correlated with elevated pesticide exposure. Data demonstrated that repeated pesticide exposure may exert a long-term adverse impact on human health.

Translating agricultural health and medicine education across the Pacific: a United States and Australian comparison study.

BACKGROUND: Populations in agricultural communities require health care that is interdisciplinary and cross-sectoral to address the high rate of workplace deaths, preventable injuries and illness. These rates are compounded by limited access to services and the distinctive personal values and culture of farming populations, which both health and rural practitioners must be aware of to reduce the gap between rural and urban population health outcomes. To address the unique health and medical characteristics of agricultural populations, education in agricultural medicine was established through the College of Medicine and the College of Public Health at the University of Iowa in the USA. The course was initially developed in 1974 for teaching medical students, family medicine residents and nurses, and a postgraduate curriculum was added in 2006 to develop medical/health and rural professionals' cultural competence to work in agricultural communities. This article reviews the adaptation of the US course to Australia and the educational and practice outcomes of students who completed the agricultural medicine course in either Australia or the USA. METHODS: Data were collected from students who completed either the Agricultural Medicine: Occupational and Environmental Health for Rural Health Professionals course in the state of Iowa in the USA or the Agricultural Health and Medicine course in the state of Victoria in Australia between 2010 and 2013 (inclusive). Data were analysed using descriptive statistics, frequencies and the χ2 test. Students were invited to make any other comments regarding the course. RESULTS: One hundred and ten students completed the survey (59 from the USA and 51 from Australia) with over a 50% response from both countries, indicating the high level of commitment to this discipline. Responses were consistent across both continents, with more than 91% agreeing that the course improved their abilities to diagnose, prevent and treat rural and agricultural populations. Further, both courses successfully enabled a multidisciplinary and cross-sectoral approach to agricultural health and medicine. CONCLUSIONS: More than 72% of previous students were practising in rural and /or mixed communities at the time of the survey, demonstrating a repeatable and transferable medical education program that supports multidisciplinary care and scholarship while addressing health inequities in agricultural populations. Findings from this study indicate there are opportunities to expand globally.

Low-level mercury, omega-3 index and neurobehavioral outcomes in an adult US coastal population.

BACKGROUND: Neurodevelopmental effects of omega-3 fatty acids and mercury from fish consumption have been characterized in children. In contrast, neurobehavioral outcomes associated with fish are not well studied in adults. OBJECTIVE: This study of avid seafood consumers on Long Island (NY, USA) sought to define associations between mercury, seafood consumption, omega-3 fatty acids and neurobehavioral outcomes. METHODS: A computer-based test system was used to assess neurobehavioral function. Blood total Hg (Hg) and omega-3 index were measured in 199 adult avid seafood eaters, who also completed the neurobehavioral assessment and an extensive food and fish frequency and demographic questionnaire. RESULTS: For most of the outcomes considered, neither Hg nor omega-3 index was associated with neurobehavioral outcomes after adjustment for key confounding variables. Fish consumption, however, was associated with decreased odds of both self-reported fatigue (OR 0.85; 95 % CI 0.72, 1.01) and a constellation of neurologic symptoms (OR 0.79; 95 % CI 0.66, 0.96). CONCLUSIONS: Results from our study provide little evidence that omega-3 fatty acids or Hg is associated with cognitive function in adult avid seafood consumers. Larger studies are needed to confirm our finding of associations between fish consumption and decreased self-reported fatigue and neurologic impairment.

Cadmium exposure and neuropsychological development in school children in southwestern Spain.

This study assessed the association between cadmium exposure and neuropsychological development in children from a region with high industrial and mining activities in southwestern Spain. We conducted a cross-sectional study with 261 children aged 6-9 years between January and March 2012. Cadmium exposure was measured in urine and hair of children, and neuropsychological development was assessed with the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) and with three computerized tests from the Behavioral Assessment and Research System (BARS): Reaction Time Test (RTT), Continuous Performance Test (CPT) and Selective Attention Test (SAT). Multivariate linear regression models, adjusted for potential confounders, were used to estimate the association between neuropsychological development and cadmium exposure measured in urine and hair samples. Geometric means of urine and hair cadmium levels were 0.75 µg/g creatinine and 0.01 µg/g, respectively. We observed that doubling of levels of cadmium in urine was associated with a reduction of two points (95% CI: -3.8 to -0.4) in the Full-Scale intelligence quotient (IQ) in boys. By domains, association was statistically significant for Verbal Comprehension (ß=-2.0; p=0.04) and close to the significance level for Perceptual Reasoning (ß=-1.8; p=0.06). Among girls, only Verbal Comprehension showed suggestive associations with cadmium exposure (ß=-1.7; p=0.06). Cadmium exposure is associated with cognitive delays in boys in our region. Our results provide additional evidence of the neurotoxic effect of low-level postnatal cadmium exposure among children, and support the hypothesis of differences between sexes in the neurotoxic effect of metals on children.

Characterizing exposures and neurobehavioral performance in Egyptian adolescent pesticide applicators.

Children and adolescents may have occupational exposure to pesticides. Although previous studies examining prenatal pesticide exposure have identified neurobehavioral deficits in children, there are limited studies examining the impact of occupational exposure in children. The objectives of this study are to estimate exposures to the organophosphorus pesticide, chlorpyrifos (CPF), by measuring urinary levels of 3,5,6-trichloro-2-pyridinol (TCPy), a specific CPF metabolite, and blood cholinesterase (ChE) activities and to characterize neurobehavioral performance in adolescents working as seasonal pesticide applicators and non-applicator controls. A neurobehavioral test battery, consisting of 14 tests, was used to assess a broad range of functions. Applicators performed worse than controls on the majority of tests. Principal component analysis was used to reduce the number of outcome variables and two components, focused on reasoning-short-term memory and attention-executive functioning, showed significant deficits in applicators compared to non-applicators. Elevated metabolite levels were found in the applicators compared to the non-applicators, confirming CPF exposure in the applicators. Although this study is limited by a small sample size, it provides preliminary evidence of moderate CPF exposures, decreased blood ChE in some applicators and decreased neurobehavioral performance in an adolescent working population.

Neuropsychological functioning among chronic khat users in Jazan region, Saudi Arabia.

BACKGROUND: Khat chewing effects in the central nervous system are attributed to cathinone and cathine, which are structurally related to amphetamine. However, studies on neuropsychological problems arising from khat use in humans are not extensive and have only included observational and single-case studies. The aims of this study were to (1) to examine neuropsychological functions among khat chewers, and (2) to determine factors affecting neuropsychological outcomes among khat chewers. METHODS: A sample of 70 adult male khat chewers and a control group of 72 nonchewers were recruited from the Jazan region in southwest Saudi Arabia. A questionnaire examining socioeconomic background, medical and occupational history, education, and khat chewing behaviors was administered. Neuropsychological performance was assessed using computerized tests from the Behavioral Assessment and Research System (BARS) that assessed learning, episodic and working memory, motor speed/coordination, attention/information processing speed, sustained attention, set-shifting/response inhibition, and perceptual functions; noncomputerized tests, Trail Making A and B, Block Design, and Benton Visual Retention tests were also administered. RESULTS: Khat chewers performed significantly worse on 3 out of 14 neuropsychological subtests compared with the control group, representing learning, motor speed/coordination, and set-shifting/response inhibition functions. Age and educational level were identified as predictors of neuropsychological outcomes of khat chewers. CONCLUSIONS: The chronic chewing of khat leaves is associated with deficits in some neuropsychological functions, which may affect the mental and neurological health of communities in which khat chewing is a common habit.

Adaptation of a neurobehavioral test battery for Thai children.

BACKGROUND: Exposure to neurotoxicants is a world wide problem with significant health implications for child development. In spite of higher neurotoxicant exposures, many developing countries do not have established neuropsychological instruments. OBJECTIVE: This study evaluated the adaptation and reliability of a computer and examiner administered Behavioral Assessment and Research System (BARS) that includes tests of motor speed and dexterity, attention, memory, and visuospatial coordination for use in Thailand. MATERIAL AND METHODS: To assess test-retest and alternate form reliability, BARS was administered to 24 healthy, 6-8 year old urban Thai children during two testing sessions two weeks apart. A comparison group of 29 healthy, rural Thai children of similar age and sex completed the BARS as part of another study and comprised a comparison group. RESULTS: Test-retest reliabilities for tests without alternate forms ranged from 0.41 to 0.77, but reliabilities were lower for tests with alternate forms (0.11 to 0.83). Paired t-tests revealed few significant differences in group performance between test administrations. Performance of urban Thai participants was compared to 29 rural Thai participants of similar age and sex. Parental education was significantly greater for urban vs. rural participants, resulting in significant differences in performance on tests of motor speed. CONCLUSIONS: This study supports the use of BARS for epidemiologic studies of neurotoxicants in Thailand, but highlights the sensitivity of these tests to differences in parental education and the need for improved alternate test forms.

Organophosphorus pesticide exposure from house dust and parent-reported child behavior in Latino children from an orchard community.

BACKGROUND: Organophosphorus pesticide (OP) exposure is known to have adverse effects on the nervous system. Children from agricultural communities are at risk of exposure to these chemicals from their indoor environments that can lead to neurological and developmental problems, including changes in behavior. OBJECTIVE: The aim of this study is to evaluate whether the take-home pathway exposure is associated with behavioral and emotional problems in Latino Orchid Community children. METHOD: The study was implemented over a period of two years (2008-2010) in an orchard farming community with a total of 324 parents who had children between the ages of 5-12 years old. Mothers of the children were asked to complete the Child Behavior Checklist (CBCL) and dust from their carpets was collected. Emotional and behavioral deficits were assessed based on the CBCL and house dust was assessed for OP concentrations. In this study, correlations between OPs in house dust and CBCL subscales were estimated using linear regression models with total OP concentrations classified by tertiles. This study also facilitated the comparison between the agricultural and non-agricultural families in terms of behavioral deficits and house dust concentrations of pesticides. RESULTS: The data from the study shows that there was a positive association between the concentration of OP residues in house dust and internalizing behavior (ß=2.06, p=0.05) whereas the association with externalizing behavior was not significant after accounting for sociocultural covariates. Significant positive associations of OP residues with somatic problems (p=0.02) and thought problems (p=0.05) were also found. CONCLUSION: The data support a potential role of OP exposure in childhood development, with a specific focus on internalizing behavior. Future work focused on longitudinal studies may uncover the long-term consequences of OP exposure and behavior.

Associations of a toenail metal mixture with attention and memory in the Gulf long-term follow-up (GuLF) study.

BACKGROUND: Research on metal-associated neurodegeneration has largely focused on single metals. Since metal exposures typically co-occur as combinations of both toxic and essential elements, a mixtures framework is important for identifying risk and protective factors. This study examined associations between toenail levels of an eight-metal mixture and attention and memory in men living in US Gulf states. METHODS: We measured toenail concentrations of toxic (arsenic, chromium, lead, and mercury) and essential (copper, manganese, selenium, and zinc) metals in 413 non-smoking men (23-69 years, 46 % Black) from the Gulf Long-Term Follow-Up (GuLF) Study. Sustained attention and working memory were assessed at the time of toenail sample collection using the continuous performance test (CPT) and digit span test (DST), respectively. Associations between toenail metal concentrations and performance on neurobehavioral tests were characterized using co-pollutant adjusted general linear models and Bayesian Kernel Machine Regression. RESULTS: Adjusting for other metals, one interquartile range (IQR) increase in toenail chromium was associated with a 0.19 (95 % CI: -0.31, -0.07) point reduction in CPT D Prime score (poorer ability to discriminate test signals from noise). One IQR increase in toenail manganese was associated with a 0.20 (95 % CI, -0.41, 0.01) point reduction on the DST Reverse Count (fewer numbers recalled). Attention deficits were greater among Black participants compared to White participants for the same increase in toenail chromium concentrations. No evidence of synergistic interaction between metals or adverse effect of the overall metal mixture was observed for either outcome. CONCLUSIONS: Our findings support existing studies of manganese-related memory deficits and are some of the first to show chromium related attention deficits in adults. Longitudinal study of cognitive decline is needed to verify chromium findings. Research into social and chemical co-exposures is also needed to explain racial differences in metal-associated neurobehavioral deficits observed in this study.

Safety Measures, Pesticide Concerns and Resources Utilized among Young Adult Workers: A Brief Report.

INTRODUCTION: Resources on pesticide information are widely available; however, little is known about the concerns young agricultural workers have about pesticides, whether they use existing resources to find information about pesticides, and how these resources influence safety behaviors such as personal protective equipment (PPE) use. OBJECTIVES: To examine demographic characteristics, safety measures, concerns about pesticide use and resources for pesticide information. METHODS: Young agricultural workers were recruited through three collegiate agricultural programs and completed an online questionnaire related to pesticide safety and use. RESULTS: Most participants who applied pesticides reported always wearing gloves (60.5%), using a tractor with an enclosed cab (68.4%), and always wearing long pants (76.3%). Among all participants, pesticide drift to crops (65.1%) and water contamination (62.3%) were the biggest concerns among young agricultural workers. The internet was the most utilized source to locate information about pesticides (76.4%), with the most common internet resources being online materials from universities or colleges (71.6%), the government (69.1%), or pesticide companies (66.7%). Accessibility (90.6%) and speed (78.3%) were the most common reasons for using the internet for information. Misinformation was the most common barrier (80.2%). CONCLUSIONS: Future studies should examine the accuracy and accessibility of pesticide information available on the internet since young adult workers rely on these resources for pesticide information.

Organizational Resources and Social Support Influences on Stress and Depression: A Comparison among Cooperative and Non-Cooperative Farmers.

BACKGROUND: Farmers are disproportionally affected by depression and suicide. Social connectedness has been shown to reduce depression and suicide among the general population but its impact on farmers is less well-known. Our previous research indicated that farmers who had cooperative resources and social support reported decreased symptoms of depression. However, it was unclear whether farmers who were not cooperative members or utilized resources from non-cooperative organizations differed from cooperative farmers in mental health. METHODS: A survey consisted of online self-completion and phone interviews was conducted among 307 participants (197 co-op, 110 non-co-op) to examine whether Midwest (north central United States) cooperative and non-cooperative farmers differ in perceived stress and symptoms of depression and whether potential differences were impacted by program use, program satisfaction, and social support. RESULTS: Cooperative farmers reported lower perceived stress and symptoms of depression than non-cooperative farmers and the difference was statistically significant for perceived stress. Use of educational programs, such as training and mentorship, was associated with decreased perceived stress but not symptoms of depression. Satisfaction with programs and social support were associated with decreased perceived stress and symptoms of depression. Program satisfaction was observed to have more associations with decreased perceived stress and symptoms of depression than program use. CONCLUSIONS: Results reveal that organizational resources and social support can mitigate mental health risks among farmers. This study highlighted an opportunity for future investigation of social connectedness in addressing farmers' mental health.

Development of Shortened Enrichment Methods for Detection of Salmonella Typhimurium Spiked in Milk.

Rapid and accurate testing of pathogenic Salmonella enterica in dairy products could reduce the risk of exposure to the bacterial pathogens for consumers. This study aimed to reduce the assessment time needed for enteric bacteria recovery and quantification in food using the natural growth properties of Salmonella enterica Typhimurium (S. Typhimurium) in cow's milk and efficiently using rapid PCR methods. Over 5 h of 37 °C enrichment, culture and PCR methods measured increases in the non-heat-treated S. Typhimurium concentration at similar rates, with an average increase of 2.7 log10 CFU/mL between the start of enrichment and 5 h. In contrast, no bacteria were recovered by culture after S. Typhimurium in milk received heat treatment, and the number of gene copies of heat-treated Salmonella detected by PCR did not increase with the enrichment time. Thus, comparing culture and PCR data over just 5 h of enrichment time can detect and differentiate between replicating bacteria and dead bacteria.