A prospective study of cancer risk among Agricultural Health Study farm spouses associated with personal use of organochlorine insecticides.

BACKGROUND: Organochlorine insecticides (OCs) have historically been used worldwide to control insects, although most have now been banned in developed countries. Evidence for an association between OC exposures and cancer predominantly comes from occupational and population based-studies among men. We evaluated the association between the use of specific OCs and cancer among the female spouses of pesticide applicators in the Agricultural Health Study. METHODS: At enrollment (1993-1997), spouses of private applicators in the cohort provided information about their own use of pesticides, including seven OCs (aldrin, chlordane, dieldrin, DDT, heptachlor, lindane, and toxaphene), and information on potential confounders. We used Poisson regression to estimate relative risks (RRs) and 95% confidence intervals (CIs) for cancers (n ≥ 3 exposed cases) reported to state cancer registries from enrollment through 2012 (North Carolina) and 2013 (Iowa), and use of the individual OCs, as well as use of any of the specific OCs. RESULTS: Among 28,909 female spouses, 2191 (7.58%) reported ever use of at least one OC, of whom 287 were diagnosed with cancer. Most cancers were not associated with OC use. Risk of glioma was increased among users of at least one OC (Nexposed = 11, RR = 3.52, 95% CI 1.72-7.21) and specifically among lindane users (Nexposed = 3, RR = 4.45, 95% CI 1.36-14.55). Multiple myeloma was associated with chlordane (Nexposed = 6, RR = 2.71, 95% CI 1.12-6.55). Based on 3 exposed cases each, there were also positive associations between pancreatic cancer and lindane, and ER-PR- breast cancer and dieldrin. No other associations with breast cancer were found. CONCLUSIONS: Overall, there were some associations with OC use and cancer incidence, however we were limited by the small number of exposed cancer cases. Future research should attempt to expand on these findings by assessing environmental sources of OC exposures, to fully evaluate the role of OC exposures on cancer risk in women.

Association between blood cholinesterase activity, organophosphate pesticide residues on hands, and health effects among chili farmers in Ubon Ratchathani Province, northeastern Thailand

Background: Use of pesticides has been documented to lead to several adverse health effects. Farmers are likely to be exposed to pesticides through dermal exposure as a result of mixing, loading, and spraying. Organophosphate pesticides (OPs) are widely used in most of the agricultural areas throughout Thailand. OPs are cholinesterase inhibitors and blood cholinesterase activity is used as a biomarker of OP effects. Objective: This study aims to determine the association between blood cholinesterase activity and organophosphate pesticide residues on chili farmer's hands and their adverse health effects. Materials and Methods: Ninety chili farmers directly involved with pesticide applications (e.g. mixing, loading, spraying) were recruited and were interviewed face to face. Both enzymes, erythrocyte acetylcholinesterase (AChE) and plasma cholinesterase (PChE), were tested with the EQM Test-mate Cholinesterase Test System (Model 400). Hand wipe samples were used for collecting residues on both hands and OP residues for chlorpyrifos and profenofos were quantified using gas chromatography equipped with a flame photometric detector (GC-FPD). Results: The average activity (±SD) of AChE and PChE was 2.73 (±0.88) and 1.58 (±0.56) U/mL, respectively. About 80.0% of the participants had detectable OP residues on hands. The median residues of chlorpyrifos and profenofos were found to be 0.02 and 0.03 mg/kg/two hands, respectively. Half of participants reported having some acute health symptoms within 48 hours after applying pesticides. When adjusted for gender, number of years working in chili farming, and frequency of pesticide use, AChE activity (Adjusted OR = 0.03, 95%CI: 0.01-0.13) and detected OP residues on hands (Adjusted OR = 0.15, 95%CI: 0.02-0.95) were significantly associated with having health effects, but no significant association was found in PChE activity (Adjusted OR = 2.09, 95%CI: 0.63-6.99). Conclusions: This study suggests that regular monitoring for blood cholinesterase and effective interventions to reduce pesticide exposure to prevent health effects should be provided to chili farmers.

Aldehydes in Relation to Air Pollution Sources: A Case Study around the Beijing Olympics.

This study was carried out to characterize three aldehydes of health concern (formaldehyde, acetaldehyde, and acrolein) at a central Beijing site in the summer and early fall of 2008 (from June to October). Aldehydes in polluted atmospheres come from both primary and secondary sources, which limits the control strategies for these reactive compounds. Measurements were made before, during, and after the Beijing Olympics to examine whether the dramatic air pollution control measures implemented during the Olympics had an impact on concentrations of the three aldehydes and their underlying primary and secondary sources. Average concentrations of formaldehyde, acetaldehyde and acrolein were 29.3±15.1 µg/m3, 27.1±15.7 µg/m3 and 2.3±1.0 µg/m3, respectively, for the entire period of measurements, all being at the high end of concentration ranges measured in cities around the world in photochemical smog seasons. Formaldehyde and acrolein increased during the pollution control period compared to the pre-Olympic Games, followed the changing pattern of temperature, and were significantly correlated with ozone and with a secondary formation factor identified by principal component analysis (PCA). In contrast, acetaldehyde had a reduction in mean concentration during the Olympic air pollution control period compared to the pre-Olympic period and was significantly correlated with several pollutants emitted from local emission sources (e.g., NO2, CO, and PM2.5). Acetaldehyde was also more strongly associated with primary emission sources including vegetative burning and oil combustion factors identified through the PCA. All three aldehydes were lower during the post-Olympic sampling period compared to the before and during Olympic periods, likely due to seasonal and regional effects. Our findings point to the complexity of source control strategies for secondary pollutants.

An association between organophosphate pesticides exposure and Parkinsonism amongst people in an agricultural area in Ubon Ratchathani Province, Thailand.

BACKGROUND: Parkinson's disease (PD) is a ubiquitous disease. However, PDs prevalence in the population of agricultural communities lacks understanding and there has been no epidemiological study on the association between pesticides exposure factors and risk for PD. OBJECTIVES: To investigate the potential association between organophosphate pesticides exposure and Parkinsonism by using a screening questionnaire in agricultural areas. MATERIAL AND METHODS: Ninety elderly people living in agricultural areas participated in a cross-sectional study conducted at Tambon Hua-Rua Health Promoting Hospital in April 2014. Screening questionnaires for Parkinson's disease, Test-mate ChE (Model 400) for blood cholinesterase (ChE) levels of both blood enzymes erythrocyte cholinesterase (AChE), and plasma cholinesterase (PChE) were used as measurement tools. Descriptive statistics for frequencies and percentage distributions were used primarily to summarize and describe the data. Sensitivity, specificity, positive and negative predictive values were calculated. RESULTS: The age range of the participants was 50 to 59 years old, with an average age of 53.9±2.87 years. The majority of the participants were female (62.2%), 82.2% of respondents were farmers. Most of participants (76.7%) reported that they applied insecticides in their farms. Ninety persons participated and completed the 11-item questionnaire. Of these, 17 (18.9%) felt that they lost balance when turning or that they needed to take a few steps to turn right around and 16.7% of participants indicated that they felt the need to move slowly or stiffly. The study found the prevalence of abnormal AChE levels was 28.9% (95%CI=19.81-39.40) and 17.8% of PChE levels (95%CI=10.52-27.26). To predict Parkinsonism, AChE, and PChE level, with a cutoff score of 5 or higher there had to be a sensitivity of 0.31, specificity of 1.00, positive predictive value (PPV) of 1.00 and negative predictive value (NPV) of 0.78 for AChE. While PChE, the score value of 5 or more had a sensitivity of 0.19, specificity of 0.93, PPV of 0.38 and NPV of 0.84. CONCLUSIONS: This study described an association between pesticides exposure and Parkinsonism. The questionnaire appears to be useful for Thai agriculturists as a screening tool for Parkinsonism and cholinesterase levels regarding to pesticides exposure.

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.

Organophosphate pesticide exposure and dialkyl phosphate urinary metabolites among chili farmers in northeastern Thailand.

BACKGROUND: Chlorpyrifos and profenofos are organophosphate pesticides (OPPs), we studied exposure and urinary metabolites in an agricultural area in the northeastern of Thailand during the chili-growing season (March - April) in 2012. OBJECTIVE: This study was designed to assess pesticide exposure concentration through dermal and inhalation pathways and to find and depict a relationship between urinary metabolites and means of exposure. MATERIALS AND METHODS: To estimate the pesticides exposure concentration, dermal wipes (hand, face, and feet), dermal patches and air samples were collected from 38 chili farmers. The morning void of pre and post application urine samples was an indicator of biological monitoring in the study which derived from 39 chili farmers. RESULTS: Chlorpyrifos and profenofos residues were detected on dermal patches, face wipes, and hand wipe samples, while no significant residues were found on the feet. Using a personal air sampling technique, all air samples detected pesticide residues. However, significant correlation between dermal pesticide exposure concentration and inhalation was not found (p>0.05). For urinary metabolite levels, there was a relationship between the first pre application morning void and post application morning void (p < 0.05); similar to the association between the first pre application morning void and the second post application morning void (p < 0.05). The main relationship between pesticide exposure and urinary metabolite was found to have been relevant to dermal exposure (r= 0.405; p < 0.05). CONCLUSIONS: The results of this study could suggested that public health education training programs, including the use of appropriate personal protective equipment (PPE), should be offered for the chili growing farmers in order to improve their ability to properly use pesticides. KEY WORDS: pesticide exposure, chili farmers, urinary metabolites, organophosphate pesticides.

Microparticles of arsenic water treatment media and water softener resin observed in treated water at private wells.

Observation of arsenic water treatment adsorption media in the treated water of several homes with high arsenic private wells led to the hypothesis that treatment media was escaping the treatment systems and entering the plumbing and drinking water. Our research at 62 homes identified that microparticles of arsenic water treatment media and/or water softener resin had escaped the treatment system in 71% of the homes. This is a potential health hazard as ingesting arsenic treatment media or water softener resin may lead to an elevated ingestion exposure to arsenic and other contaminants. Potential causes of media escape from the treatment systems include media observed to be smaller in size than specifications and media breaking into smaller pieces. One interim solution to media escape is installation of a post-treatment sediment filter. New developments in media durability or treatment system design and maintenance may be needed to prevent media escaping into drinking water. PRACTITIONER POINTS: Arsenic in private wells is often treated with point-of-entry whole house adsorption systems. Arsenic adsorption treatment media and/or water softener resin was observed in treated water at 44 of 62 homes inspected. Water treatment media escaping into treated water is a potential hazardous exposure pathway. Potential causes and solutions are discussed.

Prevalence of Current Areca Nut Use and Its Associated Factors among Bhutanese Aged 15-69 Years: Analysis of the Nationally Representative STEPS Survey 2019.

BACKGROUND: Areca nut (AN) use receives less global attention than tobacco use. Studies have linked AN consumption to a range of adverse health effects, including oral cavity and pharyngeal cancers, periodontal diseases, cardiovascular diseases, diabetes, hypertension, and addiction. The masticatory use of AN is rampant in Bhutan. There is a paucity of local evidence and limited empirical studies to understand the factors associated with current AN use in Bhutan. METHODS: This analysis uses secondary data from the Bhutan STEPS Survey 2019 that included 5575 participants aged 15-69 years, selected using multistage stratified cluster sampling. The outcome variable of interest was current AN use. Weighted analysis was done to calculate the prevalence of AN use. Factors associated with AN use were assessed using multivariable logistic regression models. RESULTS: The prevalence of current AN use was 56.82% (95% confidence interval [CI]: 54.27-59.33). A significantly higher prevalence of 63.58% (95% CI: 60.58-66.48) was found in the age group of 25-39 years. Tobacco users were 17% more likely to use AN as compared to those who do not consume tobacco (adjusted odds ratio: 1.17, 95% CI: 1.08-1.26). Current alcohol consumers were 45% more likely to consume AN as compared to lifetime alcohol abstainers. CONCLUSIONS: Age, alcohol use, and tobacco use were associated with current AN use in Bhutan. There is a need to regulate access to AN while targeting young and middle-aged individuals with public health and behavioral interventions.

Pesticide Safety Behavior among Cocoa Farmers in Nigeria: Current Trends and Determinants.

BACKGROUND: There is a strong link between pesticide exposure risk and farmers' safety behavior. However, there is a lack of understanding of farmers' safety behavior in pesticide use and the psychological factors that influence it, especially in Nigeria. OBJECTIVE: This study aimed to identify safety behaviors in pesticide use and their determinants among cocoa farmers in Nigeria using the Health Belief Model (HBM). METHODS: We used a suitable questionnaire to retrieve data from 391 cocoa farmers across three major cocoa-producing belts in Nigeria. The data were analyzed using both descriptive and inferential statistics. RESULTS: Findings showed that cocoa farmers in this study sprayed insecticides, herbicides, and fungicides on their cocoa farms. The study revealed that most pesticides were not approved for cocoa production by the authority, but the farmers were still using them. The study participants overused surveyed pesticides as the quantities applied were beyond the recommended dosage by the manufacturers. Correlation analysis showed a relationship between education status, pesticide training, perceived susceptibility and cue to action, and the farmers' pesticide overuse. In all, 42.7% of the farmers showed unsafe behaviors, 49.1% showed intermediate behaviors, and just 8.2% reported safe behaviors in pesticide use. Multiple linear regression analysis showed that perceived barriers, susceptibility, self-efficacy, and cue to action were related to age, education status, and farm experience and accounted for 59.3% of the total variance in the farmers' pesticide safety behaviors. Perceived barriers had the most significant negative influence on the farmers' behaviors, while perceived susceptibility, self-efficacy, and cue to action positively influenced the farmers' behavior. CONCLUSION: Future intervention programs in Nigeria incorporating significant variables, especially perceived barriers, in their designs with proper implementation could be more effective.

Future challenges to protecting public health from drinking-water contaminants.

Over the past several decades, human health protection for chemical contaminants in drinking water has been accomplished by development of chemical-specific standards. This approach alone is not feasible to address current issues of the occurrence of multiple contaminants in drinking water, some of which have little health effects information, and water scarcity. In this article, we describe the current chemical-specific paradigm for regulating chemicals in drinking water and discuss some potential additional approaches currently being explored to focus more on sustaining quality water for specific purposes. Also discussed are strategies being explored by the federal government to screen more efficiently the toxicity of large numbers of chemicals to prioritize further intensive testing. Water reuse and water treatment are described as sustainable measures for managing water resources for potable uses as well as other uses such as irrigation.

Agricultural Pesticide Management in Thailand: Situation and Population Health Risk.

As an agricultural country and one of the world's major food exporters, Thailand relies heavily on the use of pesticides to protect crops and increase yields. During the past decade, the Kingdom of Thailand has experienced an approximate four-fold increase in pesticide use. This increase presents a challenge for the Royal Thai Government in effectively managing and controlling pesticide use based upon the current policies and legal infrastructure. We have reviewed several key components for managing agricultural pesticides in Thailand. One of the main obstacles to effective pesticide regulation in Thailand is the lack of a consolidated, uniform system designed specifically for pesticide management. This deficit has weakened the enforcement of existing regulations, resulting in misuse/overuse of pesticides, and consequently, increased environmental contamination and human exposure. This article provides a systematic review of how agricultural pesticides are regulated in Thailand. In addition, we provide our perspectives on the current state of pesticide management, the potential health effects of widespread, largely uncontrolled use of pesticides on the Thai people and ways to improve pesticide management in Thailand.

Investigation of Prenatal Pesticide Exposure and Neurodevelopmental Deficits in Northern Thailand: Protocol for a Longitudinal Birth Cohort Study.

BACKGROUND: Prenatal exposure to pesticides has been linked to adverse neurodevelopmental outcomes. Gaps exist in the current literature about the timing and magnitude of exposures that result in these adverse outcomes. OBJECTIVE: The Study of Asian Women and their Offspring's Development and Environmental Exposures (SAWASDEE) cohort was established to investigate the impact of prenatal exposure to pesticides on early indicators of cognitive and motor skills, inhibitory control, emotion regulation, and memory that have been found to be important in the development of subsequent neurobehavioral and neurodevelopmental diseases. The overarching goal is to find earlier predictors of potential adverse neurologic outcomes in order to enable earlier interventions that could result in better outcome prognoses. METHODS: Recruitment of this prospective, longitudinal birth cohort began in July 2017 and was completed in June 2019 in Chom Thong and Fang, 2 farming districts in Chiang Mai Province in northern Thailand. Follow-up of the study participants is ongoing. During pregnancy, 7 questionnaires were administered. Time-resolved biospecimen samples were collected monthly (for urine) and during each trimester (for blood) during antenatal care visits. Medical records were abstracted. Infants were administered the NICU Network Neurobehavioral Scale (NNNS) test at 1 month of age. A total of 322 mother-child pairs completed the NNNS test. All children will be followed until 3 years of age and undergo a series of neurodevelopmental tests. We will complete several additional exposure related analyses. RESULTS: A total of 1298 women were screened, and of those, 394 (30.35%) women were enrolled. The mean gestational age at enrollment was 9.9 weeks (SD 2.6). Differences in literacy were observed between Chom Thong and Fang participants. In Fang, about 54 of 105 (51.4%) participants reported being able to read in Thai compared to about 206 of 217 (94.9%) participants in Chom Thong. The percentages were comparable for reporting to be able to write in Thai. CONCLUSIONS: This longitudinal birth cohort study will inform risk assessment standards for pregnant women in Thailand and other countries. Building awareness of how insecticide exposure during specific windows of pregnancy affects the neurodevelopmental trajectories of children in developing countries is a specific need recognized by the World Health Organization. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/31696.

Using the Socio-Ecological Model to Frame the Influence of Stakeholders on Cocoa Farmers' Pesticide Safety in Nigeria: Findings from a Qualitative Study.

PURPOSE: The aim of this study was to explore the roles of stakeholders on cocoa farmers' safe pesticide use in Nigeria using the socio-ecological model as the theoretical framework. METHODS: This was a cross-sectional qualitative study where participants were purposefully selected based on some criteria. Then, they were interviewed in-depth using a semi-structured interview approach. The interview guide was designed based on other literature and the study objectives. The interview transcripts were transcribed verbatim and analyzed using the content analysis technique. RESULTS: In all, 57 participants were involved in the interview process across all the study locations. Five layers of influence (cocoa farmers, pesticide retailers, extension officers, pesticide importers and government agencies) were considered. At individual level, cocoa farmers complained about lack of information from other stakeholders regarding pesticide use except retailers due to the farmers' proximity to their stores. However, pesticide safety information from the retailers were found to be inadequate due to their interest in financial gains rather than a focus on human health and the environment. Additionally, most retailers had no understanding about the characteristics of products they sold as they could not read pesticide labels. Furthermore, lack of motivations, human resources and facilities hindered effective extension education in the rural communities. Also, pesticide importers took efforts to train the farmers within their network, but majority of these trainings focused on lead farmers who were expected to disseminate the information to others. Besides, the agencies did organize training or workshop sometimes, but it was inadequate due to budget constraint. Lastly, environmental or agri-policies relating to Nigerian cocoa farmers concerning safe pesticide use and disposal were also inadequate. CONCLUSION: Generally, there was a large information gap with respect to pesticide safety between cocoa farmers and other stakeholders which undermined pesticide use safety. This study highlighted the need for government agencies in Nigeria to develop mechanisms to monitor information exchange among other stakeholders and cocoa farmers with respect to safe pesticide use and disposal.

Food Waste in Schools: A Pre-/Post-test Study Design Examining the Impact of a Food Service Training Intervention to Reduce Food Waste.

This study aimed to assess change in school-based food waste after training and implementing the Smarter Lunchrooms Movement (SLM) strategies with school food service workers. This non-controlled trial was implemented in a random sample of 15 elementary and middle schools in a Community Eligibility Program school district in the Northeast, the United States. Baseline and post-intervention food waste measurements were collected at two different time points in each school (n = 9258 total trays measured). Descriptive statistics, independent t-tests, and regression analyses were used to assess SLM strategies' impact on changes in percent food waste. The mean number of strategies schools implemented consistently was 7.40 ± 6.97 SD, with a range of 0 to 28 consistent strategies. Independent t-tests revealed that at post-test, there was a significant (p < 0.001) percent reduction (7.0%) in total student food waste and for each food component: fruit (13.6%), vegetable (7.1%), and milk (4.3%). Overall, a training session on food waste and the SLM strategies with school-based food service workers reduced school food waste. However, the extent of the training and SLM strategies to reduce food waste varied on the basis of the consistency and type of strategies implemented.

Effects of 27 mo of rotational vs. continuous grazing on horse and pasture condition.

The objective of this study was to determine whether rotational grazing generates horse, pasture, or cost benefits over continuous grazing. The study established two replicates (1.57 ha each) of rotational (R; four grazing sections and a stress lot per replicate, where horses were fed a moderate quality grass hay at 2% of body weight when not grazing) and continuous (C) grazing systems (treatments). Twelve Standardbred mares were grazed for an overall stocking rate of 0.52 ha/horse (n = 3 in each pasture). Recommended management practices for each grazing system were followed for 27 mo including three grazing seasons. Samples were collected monthly between 0800 and 1000. Results were analyzed in SAS (V9.4) using mixed model repeated-measures analysis of covariance, chi-square tests of association, and two-sample t-tests. Alpha level was set at P < 0.05. The C horses were maintained on pasture for 100% of the study duration (844 d; August 1, 2014 to November 22, 2016), while R horses had access to pasture for approximately half of this time (408 ± 33 d). The average length of grazing bout per rotational grazing section during the grazing season increased numerically each year from 7.88 ± 0.76 d in 2014, 10.0 ± 0.61 d in 2015, and 10.9 ± 0.80 d in 2016. Average horse body condition score (BCS) and body fat differed by treatment, with C horses (BCS 6.3 ± 0.05, 17.9 ± 0.15% body fat) greater than R horses (BCS 5.9 ± 0.05, 16.8 ± 0.15% body fat). Both sward height and herbage mass were greater in R (11.8 ± 0.1 cm tall; 1,513 ± 41 kg/ha) than C pastures (6.9 ± 0.1 cm tall; 781 ± 35 kg/ha). The R pastures had higher proportions of vegetative and total cover, planted grasses (tall fescue and orchardgrass), and weeds but lower proportions of grass weeds (nonplanted grasses) and other (rocks, litter, bare ground, etc.) as compared with C pastures. Digestible energy, acid detergent fiber, and calcium were higher in R vs. C pastures; however, crude protein was lower in R vs. C pastures. There were no significant differences between treatments for average monthly amount of hay fed (C, 597 ± 34.1 vs. R, 659 ± 34.1 kg) or average monthly pasture maintenance cost (C, $17.55 ± 3.14 vs. R, $20.50 ± 3.14). This study is one of few replicated experiments comparing the effects of rotational and continuous grazing for horses on pasture quality, horse condition, and production costs. The results here support the recommendation of rotational grazing for production, environmental, and ecological purposes.

Elevated lead contamination in boat-caulkers' homes in southern Thailand.

Surface-wipe lead loading was measured at various locations in the homes of 31 boat-caulkers and 31 location-matched controls to identify factors associated with household lead contamination. Data were obtained by observation checklist and questionnaire. Lead loading was significantly higher in caulkers' than in control households. Median lead loadings (in microg/ft2) of various locations in caulkers' homes were windowsill, 43.9; exterior entrance, 9.5; interior entrance, 21.1; living room floor, 9.8; and bedroom floors 15.6. Corresponding levels in control homes were all less than 0.2 microg/ft2. Regression modeling indicated that lead loading was higher in caulkers' homes that were closer to a boat-yard, in which the caulker had a longer duration of boatyard work, and in which there were no children aged under 6 years resident. Exterior and interior entrance and living room floors had lower lead loading than windowsills. However, bedroom floors had significantly higher lead loading, similar to windowsills.

Technical note: Comparing 4 techniques for estimating desired grass species composition in horse pastures.

Many methods exist for estimating species composition, but few studies compare those useful in improved horse pastures. The objective of this study was to examine 4 techniques for estimating desirable forage species composition in 2 cool-season horse pastures based on prevalence estimates, repeatability, bias, and practicality, and to select a method for use in a subsequent grazing study. The techniques included Equine Pasture Evaluation Disc (EPED), Line-Point Intercept with 3 transects of 50 observations each (LPI 3-50), LPI with 5 transects of 30 observations each (LPI 5-30), and Step Point (StPt). A generalized linear-mixed effects model procedure of SAS (GLIMMIX) with a logit link was used to test for differences among each species separately. When methods were significantly different (α = 0.05), pairwise comparisons were performed using a paired t-test. The methods did not differ in detecting creeping bentgrass (P = 0.3334) or orchardgrass (P = 0.4207), but there were differences for Kentucky bluegrass (P = 0.0082), tall fescue (P = 0.0314), and other (P = 0.0448). Repeatability plots displayed lower method repeatability as species prevalence increased. Agreement was analyzed between pairs of methods by grass species. Five out of 30 pairs showed significant overall bias (P = 0.0114, 0.0045, 0.0170, 0.0328, and 0.0404), and 3 of them were between LPI 3-50 and EPED. The LPI 3-50 and LPI 5-30 techniques agreed perfectly in prevalence and bias, as did StPt and EPED, meaning they can be used interchangeably. The techniques LPI 3-50 and EPED were the most dissimilar methods. In conclusion, StPt can be used interchangeably with LPI, but StPt was selected due to its thorough representation of the pastures and ease of use.

Arsenic Exposure and Cancer Risk Reduction with Local Ordinance Requiring Whole-House Dual-Tank Water Treatment Systems.

Arsenic, a known human carcinogen, occurs naturally in groundwater in New Jersey and many other states and countries. A number of municipalities in the Piedmont, Highlands, and Valley and Ridge Physiographic Provinces of New Jersey have a high proportion of wells that exceed the New Jersey maximum contaminant level (MCL) of 5 µg/L. Hopewell Township, located in Mercer County and the Piedmont Province, has a progressive local ordinance which requires the installation of dual-tank, point-of-entry treatment systems on affected wells.Thisprovided a unique study opportunity. Of the 55 homes with dual-tank POE treatment systems recruited into this study, 51 homes (93%) had arsenic levels under the MCL at the kitchen sink, regardless of years in service and/or maintenance schedule adherence. Based on the study participants' water consumption and arsenic concentrations, we estimate that Hopewell's arsenic water treatment ordinance, requiring POE dual-tank arsenic treatment, reduced the incidence of excess lifetime (70-year) bladder and lung cancers from 121 (1.7 cancer cases/year) to 16 (0.2 cancer cases/year) preventing 105 lifetime cancer cases (1.5 cases/year). Because the high risk of cancer from arsenic can be mitigated with effective arsenic water treatment systems, this ordinance should be considered a model for other municipalities.

Investigation of associations between exposures to pesticides and testosterone levels in Thai farmers.

We conducted a cross-sectional study to assess the relationship between pesticide exposures and testosterone levels in 133 male Thai farmers. Urine and serum samples were collected concurrently from participants. Urine was analyzed for levels of specific and nonspecific metabolites of organophosphates (OPs), pyrethroids, select herbicides, and fungicides. Serum was analyzed for total and free testosterone. Linear regression analyses revealed significant negative relationships between total testosterone and the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) after controlling for covariates (eg, age, BMI, smoking status). Positive significant associations were found between some OP pesticides and total testosterone. Due to the small sample size and the observational nature of the study, future investigation is needed to confirm our results and to elucidate the biological mechanisms.

Exposure to lead of boatyard workers in southern Thailand.

Lead oxide is used extensively in the construction and repair of wooden boats in Thailand, but the behaviors of boatyard workers that could place them at risk of contamination have not previously been documented. Baseline data on practices and behaviors of boatyard workers and on the level of worker and workplace contamination with lead were therefore collected. Fifty workers in two boatyards participated in this study. Lead exposure of workers was assessed by determining airborne and blood lead levels. A questionnaire was administered to collect information on work history, suspected exogenous lead sources, personal behavior and knowledge about lead. Evidence obtained by the study indicated that safety behavior and personal hygiene were poor--workers used no mask, gloves or hood, wore open sandals, smoked, drank, chewed and ate during work and did not wash their hands before drinking or eating. Some workers had lunch in the working area. The mean personal airborne lead of caulkers (36.4 microg/m3) was higher than that of carpenters (8.3 microg/m3). Forty-eight percent of all workers and 67% of caulkers had a blood lead level (BLL) exceeding 40 microg/dl. Multiple linear regression indicated that blood lead levels of workers were significantly related to job and education level, with significant differences between boatyards. In addition, the potential for "take-home" contamination was high; none of the workers took a shower or changed their clothes prior to going home. These results indicate a problem of lead exposure of sufficient magnitude to be a public health concern.