Self-Assessed Threshold Temperature for Cold among Poultry Industry Workers in Thailand.

The self-assessed threshold temperature for cold in the workplace is not well known. We asked 392 chicken industry workers in Thailand what they regard as the cold threshold (CT) and compared subgroups of workers using linear and quantile regressions by CT sextiles (percentiles P17, P33, P50, P67, and P83, from warmest to coldest). The variables of interest were sex, office work, and sedentary work, with age, clothing thermal insulation, and alcohol consumption as adjustment factors. The mean CT was 14.6 °C. Office workers had a 6.8 °C higher mean CT than other workers, but the difference ranged from 3.8 °C to 10.0 °C from P17 to P83. Sedentary workers had a 2.0 °C higher mean CT than others, but the difference increased from 0.5 °C to 3.0 °C through P17-P83. The mean CT did not differ between sexes, but men had a 1.6-5.0 °C higher CT at P17-P50 (>20 °C) and a 5.0 °C lower CT at P83 (<10 °C). The CT was relatively high at warm (≥10 °C), dry (relative humidity <41%), and drafty (air velocity > 0.35 m/s) worksites. We conclude that office, sedentary, and female workers and those working at warm, dry, and draughty sites are sensitive to the coldest temperatures, whereas male workers are sensitive even to moderate temperatures.

Prevalence and Factors Associated with Musculoskeletal Disorders among Thai Burley Tobacco Farmers.

This cross-sectional analysis study aimed to identify the prevalence and factors associated with musculoskeletal disorders (MSDs) among Thai Burley tobacco farmers. Subjects included 603 burley tobacco farmers from Sukhothai province. Farmers were interviewed twice, (during planting and harvesting seasons), with a questionnaire consisting of demographic and health characteristics, musculoskeletal symptoms, and ergonomic exposure questions. The subjects average age was 49.5 years, more were female (58.5%), most had only a primary education (74.3%), 38% were overweight or obese. Farmers had a significantly higher prevalence of MSDs in the lower back (37.1%), knee (28.7%), shoulder (22.9%), wrist (19.9%), and hip (8.3%) during the harvesting season than in the planting season (p < 0.05). Models found that factors influencing MSDs prevalence during planting included long work hours in seedling, tasks such as topping tobacco plants, and using machine tools, after controlling for age, gender, and body mass index (BMI). While in the harvesting season, models found tasks conducted as a group had lower MSDs prevalence than individual work when carrying fresh tobacco to the barn, piercing/threading and curing the leaves, baling the bundles, and transporting the finished goods. We recommended working in groups to reduce workload and MSDs, especially during harvesting, in burley tobacco farming.

Workplace Cold and Perceived Work Ability: Paradoxically Greater Disadvantage for More vs. Less-Educated Poultry Industry Workers in Thailand.

The association between worksite temperature and perceived work ability (WA) in various educational classes remains unknown. Therefore, we interviewed 286 poultry industry workers in Thailand about their WA and linked their responses to worksite temperature. WA was based on the self-assessment of current work ability compared with their lifetime best ability (scores 0-10). Education was classified as high (university or vocational school) or low (less education). Temperature was classified as cold (-22-10°C) or warm (10-23°C). WA and the occurrence of a low WA were regressed on worksite temperature, education, and their interaction with the adjustment for sex, age, job category, physical work strain, moving between cold and warm sites, thermal insulation of clothing, relative humidity, and air velocity. The average worksite temperature was 10°C for high- and 1°C for low-educated workers. The average WA score was 8.32 (SD, 1.33; range, 4-10) and classified as low (<8) in 23% of the workers. In highly-educated workers, the adjusted mean WA decreased from 9.11 in the warm areas to 8.02 in the cold areas and the prevalence of a low WA increased from 11 to 30%, while no significant change was observed in less-educated workers. The WA score was estimated to decline by 10% more (95% CI, 4-16%) in the cold areas for the more vs. less-educated workers and the prevalence of a poor WA was estimated to increase 3.09 times (95% CI, 1.43-5.45) more. Highly-educated workers in this industry are a risk group that should be given customized advice.

Pesticide use in Thailand: Current situation, health risks, and gaps in research and policy.

Agriculture in Thailand, which employs over 30 percent of the workforce and contributes significantly to the country's gross domestic product, is a key sector of its economy. Import and use of pesticides has increased over the past decade due to Thailand's major role as a leading exporter of food and agricultural products. The widespread and poorly regulated use of pesticides presents a potential risk to the health of farmers, farm families, the general population including children and the environment. This article is a result of the Southeast Asia GEOHealth Network Meeting of February 2019. It summarizes the current situation on pesticide use and regulation in Thailand and reports research findings on the potential health and environmental impacts of pesticide use, as well as highlighting gaps in research that could play an important and influential role in future policy initiatives on pesticides. Although Thailand has made remarkable progress in improving agricultural health and safety and similarly strong research and policy programs are being developed in other countries in the region, there are still significant gaps in research and policy that need to be filled.

Informal Workers in Thailand: Occupational Health and Social Security Disparities.

Informal workers in Thailand lack employee status as defined under the Labor Protection Act (LPA). Typically, they do not work at an employer's premise; they work at home and may be self-employed or temporary workers. They account for 62.6 percent of the Thai workforce and have a workplace accident rate ten times higher than formal workers. Most Thai Labor laws apply only to formal workers, but some protect informal workers in the domestic, home work, and agricultural sectors. Laws that protect informal workers lack practical enforcement mechanisms and are generally ineffective because informal workers lack employment contracts and awareness of their legal rights. Thai social security laws fail to provide informal workers with treatment of work-related accidents, diseases, and injuries; unemployment and retirement insurance; and workers' compensation. The article summarizes the differences in protections available for formal and informal sector workers and measures needed to decrease these disparities in coverage.

Toenail, blood, and urine as biomarkers of manganese exposure.

OBJECTIVE: This study examined the correlation between manganese exposure and manganese concentrations in different biomarkers. METHODS: Air measurement data and work histories were used to determine manganese exposure over a work shift and cumulative exposure. Toenail samples (n = 49), as well as blood and urine before (n = 27) and after (urine, n = 26; blood, n = 24) a work shift were collected. RESULTS: Toenail manganese, adjusted for age and dietary manganese, was significantly correlated with cumulative exposure in 7 to 9, 10 to 12, and 7 to 12 months before toenail clipping date, but not 1 to 6 months. Manganese exposure over a work shift was not correlated with changes in blood nor urine manganese. CONCLUSIONS: Toenails appeared to be a valid measure of cumulative manganese exposure 7 to 12 months earlier. Neither change in blood nor urine manganese appeared to be suitable indicators of exposure over a typical work shift.

Neuropsychological effects of low-level manganese exposure in welders.

While the neuropsychological effects of high manganese (Mn) exposure in occupational settings are well known, the effects of lower levels of exposure are less understood. In this study, we investigated the neuropsychological effects of lower level occupational Mn exposure in 46 male welders (mean age=37.4, S.D.=11.7 years). Each welders' cumulative Mn exposure indices (Mn-CEI) for the past 12 months and total work history Mn exposure were constructed based on air Mn measurements and work histories. The association between these exposure indices and performance on cognitive, motor control, and psychological tests was examined. In addition, among a subset of welders (n=24) who completed the tests both before and after a work shift, we examined the association between cross-shift Mn exposure assessed from personal monitoring and acute changes in test scores. Mn exposures in this study (median=12.9 µg/m³) were much lower, as compared to those observed in other similar studies. Increasing total Mn-CEI was significantly associated with slower reaction time on the continuous performance test (CPT; p<0.01), as well as worse mood for several scales on the Profile of Mood States (POMS; confused, tired, and a composite of tired and energetic, all p ≤ 0.03). Increasing Mn-CEI over the previous 12 months was significantly associated with worse mood on the sad, tense, and confused POMS scales (all p ≤ 0.03) and the association with worse CPT performance approached significance (p=0.10). Higher Mn exposure over the course of a workday was associated with worse performance on the CPT test across the day (p=0.06) as well as declines in fine motor control over the work-shift (p=0.04), adjusting for age and time between the 2 tests. Our study suggests that even at relatively low Mn exposure levels neuropsychological effects may manifest particularly with respect to attention, mood, and fine motor control.

Assessment of occupational exposure to manganese and other metals in welding fumes by portable X-ray fluorescence spectrometer.

Elemental analysis of welding fume samples can be done using several laboratory-based techniques. However, portable measurement techniques could offer several advantages. In this study, we sought to determine whether the portable X-ray fluorescence spectrometer (XRF) is suitable for analysis of five metals (manganese, iron, zinc, copper, and chromium) on 37-mm polytetrafluoroethylene filters. Using this filter fitted on a cyclone in line with a personal pump, gravimetric samples were collected from a group of boilermakers exposed to welding fumes. We assessed the assumption of uniform deposition of these metals on the filters, and the relationships between measurement results of each metal obtained from traditional laboratory-based XRF and the portable XRF. For all five metals of interest, repeated measurements with the portable XRF at the same filter area showed good consistency (reliability ratios are equal or close to 1.0 for almost all metals). The portable XRF readings taken from three different areas of each filter were not significantly different (p-values = 0.77 to 0.98). This suggested that the metal rich PM(2.5) deposits uniformly on the samples collected using this gravimetric method. For comparison of the two XRFs, the results from the portable XRF were well correlated and highly predictive of those from the laboratory XRF. The Spearman correlation coefficients were from 0.325 for chromium, to 0.995 for manganese and 0.998 for iron. The mean differences as a percent of the mean laboratory XRF readings were also small (<5%) for manganese, iron, and copper. The differences were greater for zinc and chromium, which were present at very low amounts in our samples and below the limits of detection of the portable XRF for many of the samples. These five metals were moderately to strongly correlated with the total fine particle fraction on filters (Spearman rho = 0.41 for zinc to 0.97 for iron). Such strong correlations and comparable results suggested that the portable XRF could be used as an effective and reliable tool for exposure assessment in many studies.