Risk factors, erythrocyte acetylcholinesterase inhibition, and self-reported symptoms of pesticide intoxication among farmers in Thailand: A cross-sectional study.

Background: Organophosphate and carbamate pesticides are widely used, and their adverse health effects remain a serious problem. Objectives: This investigation aimed to describe risk factors, erythrocyte acetylcholinesterase (AChE) inhibition, and self-reported symptoms and to derive an association between influence factors and erythrocyte AChE inhibition among farmers in Thailand. Methods: A cross-sectional study was conducted on 71 farmers from August to October 2022. General characteristics and pesticide exposure factors were elicited via a questionnaire-based interview. The erythrocyte AChE inhibition was assessed using the EQM Test-mate Cholinesterase (Model 400) instrument. Data were presented descriptively and analyzed statistically using Chi-square and binary logistic regression. Results: Most farmers were over 50 years old and had an abnormal body mass index (BMI) without alcohol consumption and smoking. Aprons (18.31%) and protective eyewear (12.68%) as personal protective equipment (PPE) were found to be used less often. The level of hemoglobin-adjusted erythrocyte AChE (Q) was considered normal when it was 59.15% and abnormal when it was 40.85%. Self-reported symptoms were confirmed to be associated with lower erythrocyte AChE levels. The Chi-square analysis showed that shortness of breath, irritation, headache, dizziness, sleep fragmentation, and memory problems were significantly associated with erythrocyte AChE (p < 0.05). The bivariate analysis revealed that farmers who consumed alcohol while using pesticides (mixing, loading, and spraying) (OR=35.821, 95% CI=4.591-279.490), who did not wear a mask while using pesticides (OR=11.898, 95% CI=1.061-133.440), and who did not wear boots while using pesticides (OR=0.166, 95% CI=0.031-0.890) had an increased likelihood of having a severe inhibition of erythrocyte AChE. Conclusions: These findings suggest that the promotion of risk prevention practices must be imposed on appropriate pesticide handling and PPE use among farmers.

Non-carcinogenic health risk from carbamate pesticide exposure of toddlers living in agricultural areas of Thailand.

Toddlers in agricultural areas may be athave risk from pesticide exposure . A cross-sectional study was conducted with 130 toddlers and their caregivers. Face-to-face interviews were done to gather information about exposure factors. A wipe sampling technique was used to collect carbamate residues on each toddler's hands and feet. Results showed that there were carbamate residues on all wipe samples (100%), with a median concentration of 30.47 micrograms per sample (hands and feet). Carbamate residues detected on toddlers' hands and feetwere significantly associated (p < 0.05) with many factors, including the toddlers' relationships with caregivers, the education level of caregivers, the household incomes, the gender of toddlers, the frequency of following caregivers to farms, the frequency of foot washing, daytime activities, and playing durations. The health risk from dermal carbamate exposurewas above the acceptable range (HI = 3.244). Preventive measures should be considered to reduce toddlers' pesticide exposure in agricultural areas.

Urinary Concentrations of Dialkylphosphate Metabolites of Organophosphate pesticides in the Study of Asian Women and their Offspring's Development and Environmental Exposures (SAWASDEE).

BACKGROUND: Measurements of urinary dialkyl phosphate (DAP) metabolites are often used to characterize exposures to organophosphate (OP) insecticides; however, some challenges to using urinary DAP metabolites as an exposure measure exist. OP insecticides have short biological half-lives with measurement in a single urine sample typically only reflecting recent exposure within the last few days. Because of the field staff and participant burden of longitudinal sample collection and the high cost of multiple measurements, typically only one or two urine samples have been used to evaluate OP insecticide exposure during pregnancy, which is unlikely to capture an accurate picture of prenatal exposure. METHODS: We recruited pregnant farmworker women in Chom Thong and Fang, two districts of Chiang Mai province in northern Thailand (N = 330) into the Study of Asian Women and their Offspring's Development and Environmental Exposures (SAWASDEE) from 2017 to 2019. We collected up to 6 serial urine samples per participant during gestation and composited the samples to represent early, mid, and late pregnancy. We measured concentrations of urinary DAP metabolites in the composited urine samples and evaluated the within- and between-participant variability of these levels. We also investigated predictors of OP insecticide exposure. RESULTS: DAP metabolite concentrations in serial composite samples were weakly to moderately correlated. Spearman correlations indicated that composite urine samples were more highly correlated in Fang participants than in Chom Thong participants. The within-person variances (0.064-0.65) exceeded the between-person variances for DETP, DEP, ∑DEAP, DMP, DMTP, ∑DMAP, ∑DAP. The intraclass correlations (ICCs) for the volume-based individual metabolite levels (ng/mL) ranged from 0.10 to 0.66. For ∑DEAP, ∑DMAP, and ∑DAP the ICCs were, 0.47, 0.17, 0.45 respectively. We observed significant differences between participants from Fang compared to those from Chom Thong both in demographic and exposure characteristics. Spearman correlations of composite samples from Fang participants ranged from 0.55 to 0.66 for the ∑DEAP metabolite concentrations in Fang indicating moderate correlation between pregnancy periods. The ICCs were higher for samples from Fang participants, which drove the overall ICCs. CONCLUSIONS: Collecting multiple (∼6) urine samples during pregnancy rather than just 1 or 2 improved our ability to accurately assess exposure during the prenatal period. By compositing the samples, we were able to still obtain trimester-specific information on exposure while keeping the analytic costs and laboratory burden low. This analysis also helped to inform how to best conduct future analyses within the SAWASDEE study. We observed two different exposure profiles in participants in which the concentrations and variability in data were highly linked to the residential location of the participants.

Related health risk assessment of exposure to arsenic and some heavy metals in gold mines in Banmauk Township, Myanmar.

Exposure to heavy metals in mining activities is a health issue among miners. This study was carried out at three small-scale gold mining sites situated in Banmauk Township, Myanmar and aims to assess the occupational health risks of small-scale gold miners who are exposed to arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb) in the soil through the dermal route. Soil samples were analyzed through atomic absorption spectroscopy (AAS). The concentrations of the heavy metals in soils found As, ranged 1.04 mg/kg to 22.17 mg/kg, 0.13 mg/kg to 3.07 mg/kg for Cd, 0.15 mg/kg to 77.44 mg/kg for Hg, and 7.67 mg/kg to 210.00 mg/kg for Pb. In this study, 79% of the participants did not use any form of personal protective equipment (PPE) while working in gold mining processes. Regarding noncancer risk assessment, the results found all hazard quotient were lower than acceptable level (HQ < 1). In addition, all hazard index (HI) was lover than 1, the highest HI was found as 5.66 × 10-1 in the amalgamation process. On the other hand, the result found cancer risk ranged from 8.02 × 10-8 to 1.75 × 10-6, and the estimated cancer risks for 9 years ranged from 4.78 × 10-7 to 1.04 × 10-5. Therefore, the cancer risks of the miners were greater than the United State Environmental Protection Agency (U.S. EPA) acceptable cancer risk level, 1 × 10-6, and the miners may be at risk of developing carcinogenic diseases. The suggestion is to educate miners about the health risks of heavy metals and to encourage the use of proper PPE all the time while working in gold mine.

Occupational noise exposure and hearing defects among sawmill workers in the south of Thailand.

The aim of this study was to investigate occupational noise exposure and hearing defects among sawmill workers in the south of Thailand. Seven hundred sawmill workers participated, of which 335 (47.9%) were male. The mean age of the sawmill workers was 33.5 years (SD 10.2), and more than 60% were <35 years old; 75.1% of the workers had less than 5 years of work experience. Only about one in four workers (25%) had been trained in use of personal protective equipment (PPE), and half of the participants never or rarely wore PPE while working. The prevalence rate of noise-induced hearing loss (NIHL) was 22.8% (N = 42). Male workers had significantly higher risk than female workers (odds ratio [OR] = 2.21). Workers aged older than 25 years had significantly higher risks for NIHL (OR = 3.51-12.42) than workers younger than 25 years. Sawing workers had higher risk for NIHL than office workers (OR = 3.07).

Using hair and fingernails in binary logistic regression for bio-monitoring of heavy metals/metalloid in groundwater in intensively agricultural areas, Thailand.

In this study, the hair and fingernails of the local people in an intensively cultivated agricultural area in Ubon Ratchathani province, Thailand, were used as biomarkers of exposure to arsenic (As) and heavy metals. The study area has shallow acidic groundwater that is contaminated with As and heavy metals. The local people often consume this shallow groundwater; thus, they are exposed to As and heavy metals. Hair and fingernail samples were collected to characterize the differences between shallow groundwater drinking (SGWD) and tap water drinking (TWD) residents. The concentrations of As and the heavy metals Cd, Pb and Hg were significantly higher in the hair samples from the SGWD group than those from the TWD group, especially for As (0.020-0.571 vs. 0.024-0.359µg/g) and Cd (0.009-0.575 vs. 0.013-0.230µg/g). Similarly, the concentrations of As and the heavy metals in the fingernail samples collected from the SGWD group were larger than those of the TWD group, especially for As (0.039-2.440µg/g vs. 0.049-0.806µg/g). The χ2 statistic and binary logistic regression were used to find the associated factors and assess the associated probabilities. The regression results show that the factors associated with the concentrations of As and the heavy metals in the hair samples were drinking water source, rate of water consumption, gender, bathing water source, education, smoking and underlying disease, whereas the factors associated with the concentrations of these species in the fingernail samples were drinking water source, gender, occupation, work hours per day, alcohol consumption, and the use of pesticides.

Using urine as a biomarker in human exposure risk associated with arsenic and other heavy metals contaminating drinking groundwater in intensively agricultural areas of Thailand.

Urine used as a biomarker was collected and compared between two groups of participants: (1) a groundwater-drinking group and (2) a non-groundwater-drinking group in intensively agricultural areas in Ubon Ratchathani province, Thailand. The statistical relationship with the metal concentration in shallow groundwater wells was established with urine data. According to the groundwater data, the health risk assessment results for four metals appeared to be higher for participants who drank groundwater than for the other group. The carcinogenic risk and non-carcinogenic risk of arsenic (As) were found in 25.86 and 31.03% of participants, respectively. For lead (Pb), 13.79% of the participants had a non-carcinogenic risk. Moreover, 30 of the 58 participants in the groundwater-drinking group had As urine higher than the standard, and 26, 2 and 9 of the 58 participants had above-standard levels for cadmium (Cd), Pb and mercury (Hg) in urine, respectively. Both the risk assessment and biomarker level of groundwater-drinking participants were higher than in the other group. The results showed an average drinking rate of approximately 4.21 ± 2.73 L/day, which is twice as high as the standard. Interestingly, the As levels in the groundwater correlated with those in the urine of the groundwater-drinking participants, but not in the non-groundwater-drinking participants, as well as with the As-related cancer and non-carcinogenic risks. The hazard index (HI) of the 100 participants ranged from 0.00 to 25.86, with an average of 1.51 ± 3.63 higher than the acceptable level, revealing that 28 people appeared to have non-carcinogenic risk levels (24 and 4 people for groundwater-drinking participants and non-groundwater-drinking participants, respectively). Finally, the associated factors of heavy metals in urine were the drinking water source, body weight, smoking, sex and use of personal protective equipment.

Occupational noise-induced hearing loss in auto part factory workers in welding units in Thailand.

OBJECTIVES: Most workers in auto part factories in Thailand are usually exposed to excessive noise in their workplace. This study aimed to assess the level of occupational noise-induced hearing loss and investigate risk factors causing hearing loss in auto part factory workers in the welding units in Thailand. METHODS: This was a cross-sectional study. One hundred eighty subjects were recruited from 356 workers in the welding unit of three factories. Sixty eligible subjects in each factory were selected by systemic random sampling. The subjects were interviewed using a face-to-face questionnaire. Noise exposure levels and audiograms were measured by a noise dosimeter and an audiometer, respectively. RESULTS: The findings confirmed that noise exposure levels of 86-90 dB (A) and exceeding 90 dB (A) significantly increased the risk of hearing loss in either ear. A noise exposure level exceeding 90 dB (A) significantly increased the prevalence of hearing loss in both ears. Regarding, a 10-pack-year smoking history increased the prevalence of hearing loss in either ear or both ears. In addition, subjects with employment duration exceeding 10 years significantly developed hearing loss in either ear. CONCLUSIONS: The engineering control or personal control by wearing hearing protection device should be used to decrease noise exposure levels lower than 85 dB (A) for 8 h. Moreover, if the exposure level reaches 85 dB (A) for 8 h, the employer needs to implement a hearing conservation program in the workplace.

Salivary cotinine levels as a biomarker for green tobacco sickness in dry tobacco production among Thai traditional tobacco farmers.

BACKGROUND: Dry Thai traditional tobacco (Nicotiana Tabacum L.) production involves a unique process: (a) picking tobacco leaves, (b) curing tobacco leaves, (c) removing stems of tobacco leaves, cutting leaves and putting on a bamboo rack, (d) drying in the sun, reversing a rack, spraying a tobacco extract to adjust the tobacco's color, storing dried tobacco and packaging. These processes may lead to adverse health effects caused by dermal absorption of nicotine such as Green Tobacco Sickness (GTS). OBJECTIVES: The aim of this study was to determine the correlation between GTS resulting from dry Thai traditional tobacco production and salivary cotinine levels among Thai traditional tobacco farmers in Nan Province, Thailand. MATERIALS AND METHODS: A prospective cohort study was conducted with 20 tobacco farmers and 20 non-tobacco farmers in Praputtabath Sub-District and Phatow Sub-District. The participants were randomly selected and interviewed using in person questionnaires with bi-weekly follow-up for 14 weeks. During each contact, the cotinine concentration was measured by NicAlert(TM) Saliva strip tests (NCTS). Descriptive statistics and Spearman's correlation (Spearman's rho) was used to examine the relationship between the variables at both 0.01 and 0.05 significant probability levels. RESULTS: This study indicated that GTS from dry tobacco production has the potential to be considered a common occupational disease. This study demonstrated the usefulness of salivary cotinine level measurements by NCTS. The levels were well correlated with farmers who were employed in the dry Thai tobacco production industry. Salivary cotinine levels were also significantly correlated with the prevalence of GTS in the group of tobacco farmers at any given time within a crop season. However, the production process of dry Thai traditional tobacco is different from that evaluated in our previous studies where GTS and salivary cotinine level were correlated in workers working in humid conditions. CONCLUSIONS: The long-term effects of such exposure should be investigated and health education programs with health risk exposure studies to increase awareness amongst farmers is recommended.

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.

Neurobehavioral effects of exposure to organophosphates and pyrethroid pesticides among Thai children.

The use of pesticides for crop production has grown rapidly in Thailand during the last decade, resulting in significantly greater potential for exposure among children living on farms. Although some previous studies assessed exposures to pesticides in this population, no studies have been conducted to evaluate corresponding health effects. Twenty-four children from a rice farming community (exposed) and 29 from an aquaculture (shrimp) community (control) completed the study. Participants completed a neurobehavioral test battery three times at 6 month intervals: Session I: preliminary orientation; Session II: high pesticide use season; Session III: low pesticide-use season. Only sessions II and III were used in the analyses. High and low pesticide use seasons were determined by pesticide use on rice farms. Urinary metabolites of organophosphates (OPs) and pyrethroids (PYR) were analyzed from first morning void samples collected the day of neurobehavioral testing. Rice farm participants had significantly higher concentrations of dialkylphosphates (DAPs) (common metabolites of OPs) and TCPy (a specific metabolite of chlorpyrifos) than aquaculture farm children during both seasons. But, TCPy was significantly higher during the low rather than the high pesticide use season for both participant groups. Rice farm children had significantly higher DCCA, a metabolite of PYR, than aquaculture participants only during the high exposure season. Otherwise, no significant differences in PYR metabolites were noted between the participant groups or seasons. No significant adverse neurobehavioral effects were observed between participant groups during either the high or low pesticide use season. After controlling for differences in age and the Home Observation for Measurement of the Environment (HOME) scores, DAPs, TCPy, and PYR were not significant predictors of adverse neurobehavioral performance during either season. Increasing DAP and PYR metabolites predicted some relatively small improvement in latency of response. However, due to the small sample size and inability to characterize chronic exposure, any significant differences observed should be regarded with caution. Moreover although not statistically significant, confidence intervals suggest that small to moderate adverse effects of pesticide exposure cannot be ruled out for some indicators of neurobehavioral performance.

Heavy metal contamination and human health risk assessment in drinking water from shallow groundwater wells in an agricultural area in Ubon Ratchathani province, Thailand.

Most local people in the agricultural areas of Hua-ruea sub-district, Ubon Ratchathani province (Thailand), generally consume shallow groundwater from farm wells. This study aimed to assess the health risk related to heavy metal contamination in that groundwater. Samples were randomly collected from 12 wells twice in each of the rainy and the dry seasons and were analyzed by inductive coupled plasma spectrometry-mass spectrometry (ICP-MS). The concentration of detected metals in each well and the overall mean were below the acceptable groundwater standard limits for As, Cd, Cr, Cu, Hg, Ni and Zn, but Pb levels were higher in four wells with an overall average Pb concentration of 16.66 ± 18.52 µg/l. Exposure questionnaires, completed by face-to-face interviews with 100 local people who drink groundwater from farm wells, were used to evaluate the hazard quotients (HQs) and hazard indices (HIs). The HQs for non-carcinogenic risk for As, Cu, Zn and Pb, with a range of 0.004-2.901, 0.053-54.818, 0.003-6.399 and 0.007-26.80, respectively, and the HI values (range from 0.10 to 88.21) exceeded acceptable limits in 58 % of the wells. The HI results were higher than one for groundwater wells located in intensively cultivated chili fields. The highest cancer risk found was 2.6 × 10(-6) for As in well no. 11. This study suggested that people living in warmer climates are more susceptible to and at greater risk of groundwater contamination because of their increased daily drinking water intake. This may lead to an increased number of cases of non-carcinogenic and carcinogenic health defects among local people exposed to heavy metals by drinking the groundwater.

Genotoxic monitoring and benzene exposure assessment of gasoline station workers in metropolitan Bangkok: sister chromatid exchange (SCE) and urinary trans, trans-muconic acid (t,t-MA).

Early warning of the potential of mutagens or carcinogens caused by benzene exposure that might occur in gasoline station workers can be achieved by examining 2 major biomarkers: sister chromatid exchange (SCE) and trans, trans-muconic acid (t,t-MA), a urinary metabolite of benzene. The main objective of this study was to assess benzene exposure and monitor the genotoxic effect of gasoline station workers in Bangkok, Thailand. Blood and urine samples were collected from 33 gasoline station workers, working in Pathumwan district area, central Bangkok, Thailand, for SCE and t,t-MA analysis, from April to June 2009. Control samples were collected from 30 office workers and students in the same area at the same period. Our results indicated significantly higher frequencies of SCE in gasoline exposed workers were than in controls (p<0.01), independent of gender. Urinary t,t-MA and t,t-MA/creatinine levels of gasoline exposed workers were also significantly higher than the control groups (p<0.05) were significantly higher in women than men workers (p<0.01). Calculated chromosomal damage relative risk (RR) of gasoline station workers was 3.00 (95% CI = 1.81 - 4.98, p<0.001) compared to controls. The gasoline exposed workers had potentially higher risk of chromosomal damage and cancer development because of direct contact to benzene.

Inhalation exposure of organophosphate pesticides by vegetable growers in the Bang-Rieng subdistrict in Thailand.

This study investigated inhalation exposure to organophosphate pesticides (OPPs) and evaluated the associated health risks to vegetable growers living in the Bang-Rieng agricultural community. Air samples were collected by using personal sampling pumps with sorbent tubes placed in the vegetable growers' breathing zone. Samples were collected during both wet and dry seasons. Residues of organophosphate pesticides, that is, chlorpyrifos, dicrotofos, and profenofos, were analyzed from 33 vegetable growers and 17 reference subjects. Results showed that median concentrations of OPPs in air in farm areas were in the range of 0.022-0.056 mg/m(3) and air in nonfarm areas in the range of <0.0016-<0.005 mg/m(3). The concentration of the three pesticides in the vegetable growers was significantly higher than that of the references during both seasons. The results also indicate that the vegetable growers may be at risk for acute adverse effects via the inhalation of chlorpyrifos and dicrotofos during pesticide application, mixing, loading, and spraying. It is suggested that authorities and the community should implement appropriate strategies concerning risk reduction and risk management.