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Objectives. We conducted a clinic-based study of erythrocyte cholinesterase levels, pesticide exposures, and health effects among farmworkers and nonfarmworkers to determine risks for exposure and associated morbidity. Methods. Two hundred two farmworkers and 42 nonfarmworkers were recruited sequentially at two community health centers. Erythrocyte cholinesterase levels were measured colorimetrically. Questionnaires obtained data on demographics, occupational history, exposures, and symptoms. Results. Cholinesterase levels were significantly lower among farmworkers (30.28 U/g hemoglobin) than among nonfarmworkers (32.3 U/g hemoglobin). Twelve percent of farmworkers, but no nonfarmworkers, had very low levels. Farmworkers applying pesticides also had lower cholinesterase levels. One half of farmworkers reported being sprayed by pesticides and working in fields with an obvious chemical smell. Of reported symptoms, only diarrhea was associated with cholinesterase levels. Reported exposures, however, were strongly associated with symptoms. Conclusions. Farmworkers reported many pesticide exposures that violate state and federal regulations. Farmworkers had cholinesterase levels significantly lower than those of nonfarmworkers, although only spraying pesticides was associated with very low levels. (Am J Public Health. 1994;84:446-451), Migrant farmworkers are exposed to pesticides in a way that violates state and federal laws and may show lower cholinesterase levels than the rest of the population. The amount of cholinesterase in a person's body has been recognized as a way of determining exposure to pesticides, though the effect of the low cholinesterase levels has not been fully explained. Erythrocyte cholinesterase levels were measured for 202 farmworkers and 42 non farm-laborers. Both groups also filled out questionnaires used to determine their exposure to pesticides. Acetylcholinesterase levels were found to be lower in the farmworkers than the non-farmworkers, 30.18 International Units per gram (U/g) of hemoglobin and 32.20 U/g hemoglobin, respectively. Farmworkers who reported spraying pesticide showed the lowest levels of cholinesterase in the study, 2.7 U/g hemoglobin lower than other farm laborers. Two-thirds of the health related problems associated with pesticides showed a correlation with lower cholinesterase levels in the farmworkers studied.

Introduction There is growing evidence that chronic exposure to inorganic As (iAs) may increase the risk of cardiometabolic (CM) disorders, including diabetes mellitus (DM) and cardiovascular diseases (CVD) (Kuo et [...], BACKGROUND: Exposure to arsenic (As) concentrations in drinking water > 150 µg/L has been associated with risk of diabetes and cardiovascular disease, but little is known about the effects of lower exposures. OBJECTIVE: This study aimed to examine whether moderate As exposure, or indicators of individual As metabolism at these levels of exposure, are associated with cardiometabolic risk. METHODS: We analyzed cross-sectional associations between arsenic exposure and multiple markers of cardiometabolic risk using drinking-water As measurements and urinary As species data obtained from 1,160 adults in Chihuahua, Mexico, who were recruited in 2008-2013. Fasting blood glucose and lipid levels, the results of an oral glucose tolerance test, and blood pressure were used to characterize cardiometabolic risk. Multivariable logistic, multinomial, and linear regression were used to assess associations between cardiometabolic outcomes and water As or the sum of inorganic and methylated As species in urine. RESULTS: After multivariable adjustment, concentrations in the second quartile of water As (25.5 to < 47.9 µg/L) and concentrations of total speciated urinary As (< 55.8 µg/L) below the median were significantly associated with elevated triglycerides, high total cholesterol, and diabetes. However, moderate water and urinary As levels were also positively associated with HDL cholesterol. Associations between arsenic exposure and both dysglycemia and triglyceridemia were higher among individuals with higher proportions of dimethylarsenic in urine. CONCLUSIONS: Moderate exposure to As may increase cardiometabolic risk, particularly in individuals with high proportions of urinary dimethylarsenic. In this cohort, As exposure was associated with several markers of increased cardiometabolic risk (diabetes, triglyceridemia, and cholesterolemia), but exposure was also associated with higher rather than lower HDL cholesterol. http://dx.doi.org/10.1289/ehp.1408742

Introduction Exposure to air pollution from high-density urban traffic is an important public health issue. Traffic-related air pollutants are associated with acute health outcomes as well as chronic respiratory and [...], BACKGROUND AND OBJECTIVE: Exposure to traffic-related air pollutants is an important public health issue. Here, we present a systematic review and meta-analysis of research examining the relationship of measures of nitrogen oxides (N[O.sub.x]) and of various measures of traffic-related air pollution exposure with lung cancer. METHODS: We conducted random-effects meta-analyses of studies examining exposure to nitrogen dioxide (N[O.sub.2]) and N[O.sub.x] and its association with lung cancer. We identified 20 studies that met inclusion criteria and provided information necessary to estimate the change in lung cancer per 10-µg/[m.sup.3] increase in exposure to measured N[O.sub.2]. Further, we qualitatively assessed the evidence of association between distance to roadways and traffic volume associated with lung cancer. RESULTS: The meta-estimate for the change in lung cancer associated with a 10-µg/[m.sup.3] increase in exposure to N[O.sub.2] was 4% (95% CI: 1%, 8%). The meta-estimate for change in lung cancer associated with a 10-µg/[m.sup.3] increase in NOX was similar and slightly more precise, 3% (95% CI: 1%, 5%). The N[O.sub.2] meta-estimate was robust to different confounding adjustment sets as well as the exposure assessment techniques used. Trim-and-fill analyses suggest that if publication bias exists, the overall meta-estimate is biased away from the null. Forest plots for measures of traffic volume and distance to roadways largely suggest a modest increase in lung cancer risk. CONCLUSION: We found consistent evidence of a relationship between N[O.sub.2], as a proxy for traffic-sourced air pollution exposure, with lung cancer. Studies of lung cancer related to residential proximity to roadways and N[O.sub.x] also suggest increased risk, which may be attributable partly to air pollution exposure. The International Agency for Research on Cancer recently classified outdoor air pollution and particulate matter as carcinogenic (Group 1). These meta-analyses support this conclusion, drawing particular attention to traffic-sourced air pollution. http://dx.doi.org/10.1289/ehp.1408882

Introduction Arsenic (As), and specifically its inorganic forms (iAs) [arsenite ([iAs.sup.III]) and arsenate ([iAs.sup.V)], are naturally occurring drinking-water contaminants. Epidemiologic evidence (James et al. 2013; Kuo et al. 2013; Maull [...], Background: A growing number of studies link chronic exposure to inorganic arsenic (iAs) with the risk of diabetes. Many of these studies assessed iAs exposure by measuring arsenic (As) species in urine. However, this approach has been criticized because of uncertainties associated with renal function and urine dilution in diabetic individuals. Objectives: Our goal was to examine associations between the prevalence of diabetes and concentrations of As species in exfoliated urothelial cells (EUC) as an alternative to the measures of As in urine. Methods: We measured concentrations of trivalent and pentavalent iAs methyl-As (MAs) and dimethyl-As (DMAs) species in EUC from 374 residents of Chihuahua, Mexico, who were exposed to iAs in drinking water. We used fasting plasma glucose, glucose tolerance tests, and self-reported diabetes diagnoses or medication to identify diabetic participants. Associations between As species in EUC and diabetes were estimated using logistic and linear regression, adjusting for age, sex, and body mass index. Results: Interquartile-range increases in trivalent, but not pentavalent, As species in EUC were positively and significantly associated with diabetes, with ORs of 1.57 (95% CI: 1.19, 2.07) for iAsIn, 1.63 (1.24, 2.15) for [Mas.sup.III], and 1.31 (0.96, 1.84) for [DMAs.sup.III]. DMAs/MAs and DMAs/iAs ratios were negatively associated with diabetes (OR = 0.62; 95% CI: 0.47, 0.83 and OR = 0.72; 95% CI: 0.55, 0.96, respectively). Conclusions: Our data suggest that uncertainties associated with measures of As species in urine may be avoided by using As species in EUC as markers of iAs exposure and metabolism. Our results provide additional support to previous findings suggesting that trivalent As species may be responsible for associations between diabetes and chronic iAs exposure. http://dx.doi.org/10.1289/ehp.1307756

Introduction Outdoor air pollution is a complex mixture containing a number of known carcinogens and has been associated with increased lung cancer risk in many studies over the past 50 [...], Background: Particulate matter (PM) in outdoor air pollution was recently designated a Group I carcinogen by the International Agency for Research on Cancer (IARC). This determination was based on the evidence regarding the relationship of [PM.sub.2.5] and [PM.sub.10] to lung cancer risk; however, the IARC evaluation did not include a quantitative summary of the evidence. OBJECTIVE: Our goal was to provide a systematic review and quantitative summary of the evidence regarding the relationship between PM and lung cancer. METHODS: We conducted meta-analyses of studies examining the relationship of exposure to [PM.sub.2.5] and [PM.sub.10] with lung cancer incidence and mortality. In total, 18 studies met our inclusion criteria and provided the information necessary to estimate the change in lung cancer risk per 10-[micro]g/[m.sup.3] increase in exposure to PM. We used random-effects analyses to allow between-study variability to contribute to meta-estimates. RESULTS: The meta-relative risk for lung cancer associated with [PM.sub.2.5] was 1.09 (95% CI: 1.04, 1.14). The meta-relative risk of lung cancer associated with [PM.sub.10] was similar, but less precise: 1.08 (95% CI: 1.00, 1.17). Estimates were robust to restriction to studies that considered potential confounders, as well as subanalyses by exposure assessment method. Analyses by smoking status showed that lung cancer risk associated with [PM.sub.2.5] was greatest for former smokers [1.44 (95% CI: 1.04, 1.22)], followed by never-smokers [1.18 (95% CI: 1.00, 1.39)], and then current smokers [1.06 (95% CI: 0.97, 1.15)]. In addition, meta-estimates for adenocarcinoma associated with [PM.sub.2.5] and [PM.sub.10] were 1.40 (95% CI: 1.07, 1.83) and 1.29 (95% CI: 1.02, 1.63), respectively. CONCLUSION: The results of these analyses, and the decision of the IARC Working Group to classify PM and outdoor air pollution as carcinogenic (Group 1), further justify efforts to reduce exposures to air pollutants that can arise from many sources. http://dx.doi.org/10.1289/ehp.1408092

We sought to measure bicyclists' roadway exposures to particulate matter and assess whether those exposures are associated with reduced pulmonary function. Thirty-one (31) volunteer participants riding bicycles on selected routes were tracked using the Global Positioning System. Personal exposures to particulate matter (PM-10) were measured during the rides and pulmonary function tests were administered at baseline, immediately after the ride, and 2 and 6–24 hours later. Post-ride decrements in pulmonary function were observed for several outcome measures, with the largest differences immediately post-ride. Statistically-significant declines in FEV1 (-38.42, 95% Confidence Interval (CI), −63.79 to −13.05 ml), FVC (-36.89, 95% CI, −62.96, −10.84 ml), and PEFR (-162, 95% CI −316.02 to −9.49 ml/sec) were observed for each increase in decile of peak exposure. PM-10 exposures encountered on roadways may put bicyclists at risk for pulmonary deficits. [ABSTRACT FROM AUTHOR]

The relationship between fine particles and mortality is discussed. Topics include the ecological fallacy, criteria for epidemiological studies, group-level exposure variables, and bias.

The major cause of death related to the workplace is motor vehicle accidents. Studies examining this problem have been limited to small geographical areas or to particular industries. This study examined the pattern of motor vehicle deaths in the workplace in the US by examining data compiled by the National Center for Health Statistics (NCHS) from 20 states. Results showed that for men, white collar workers had somewhat fewer crash deaths; blue collar workers had somewhat more crash deaths. Death rates were 1.8 times higher than expected for miners and oil well drillers, and 1.6 times higher for transportation and moving occupations. The industry categories of transportation, communication, and utilities had 40 percent more deaths than expected. For women, the highest rates were for those employed in construction, transportation, or the military. These results indicate that motor vehicle deaths are a major hazard to workers, particularly among those in specific occupations and industries. Further studies should look for ways to increase motor vehicle safety in the workplace. (Consumer Summary produced by Reliance Medical Information, Inc.)