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Bisphenol A (BPA) is an environmental toxicant that causes adverse effects to liver even at low concentrations. Non-alcoholic fatty liver disease (NAFLD) presents as significant accumulation of lipids in the liver, impairing detoxification processes. Nevertheless, little information is available regarding the susceptibility of NAFLD to BPA toxicity. Here, we compared the effects of low concentration BPA exposure on the protein profiles of normal and NAFLD cells. We established NAFLD model by treating HepG2 cells with fatty acids and subsequently treated with low BPA concentration. Protein expression profiles showed that four proteins from normal cells and nine proteins from NAFLD cells were dysregulated after BPA treatment. A pathway analysis revealed decreased expression of translation elongation factor proteins in NAFLD cells following BPA treatment and this down-regulation was confirmed by immunoblotting. Our findings suggest that BPA toxicity is more deleterious, especially to translation elongation, in NAFLD cells than normal cells.

There is global concern about heavy metal contamination in the environment. Adverse health effects can be caused by heavy metals in contaminated food and water. Therefore, environmental monitoring studies and risk assessments should be conducted periodically. In this study, we measured levels of Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn in blood cockles (Anadara granosa) collected from three locations in the Upper Gulf of Thailand. Hazard quotients and hazard indices were calculated to evaluate the health risks posed by heavy metals in consumed blood cockles. Heavy metal concentrations in all of the blood cockle samples were lower than the relevant food standards. The hazard quotients and hazard indices were

Table S1. Carbonylated sites identified by mass spectrometry of carbonylated proteins detected with redox proteomics. (DOCX 15 kb)

The influence of temperature on bacterial virulence has been studied worldwide from the viewpoint of climate change and global warming. The bacterium enteroaggregative Escherichia coli (EAEC) is the causative agent of watery diarrhea and shows an increasing incidence worldwide. Its pathogenicity is associated with the virulence factors aggregative adherence fimbria type I and II (AAFI and AAFII), encoded by aggA and aafA in EAEC strains 17-2 and 042, respectively. This study focused on the effect of temperature increases from 29 °C to 40 °C on fimbrial gene expression using real-time PCR, and on its virulence using an aggregative adherence assay and biofilm formation assay. Incubation at 32 °C caused an up-regulation in both EAEC strains 17-2 and strain 042 virulence gene expression. EAEC strain 042 cultured at temperature above 32 °C showed down-regulation of aafA expression except at 38 °C. Interestingly, EAEC cultured at a high temperature showed a reduced adherence to cells and an uneven biofilm formation. These results provide evidence that increases in temperature potentially affect the virulence of pathogenic EAEC, although the response varies in each strain.

Nitrate contamination in groundwater is a worldwide problem especially in agricultural countries. Environmental factors, such as land-use pattern, type of aquifer, and soil-drainage capacity, affect the level of contamination. Exposure to high levels of nitrate in groundwater may contribute to adverse health effects among residents who use groundwater for consumption. This study aimed to determine the relationship between nitrate levels in groundwater with land-use pattern, type of aquifer, and soil-drainage capacity, in Photharam District, Ratchaburi Province, lower Mae Klong basin, Thailand. Health risk maps were created based on hazard quotient to quantify the potential health risk of the residents using US Environmental Protection Agency (U.S. EPA) health risk assessment model. The results showed the influence of land-use patterns, type of aquifer, and soil-drainage capacity on nitrate contamination. It was found that most of the residents in the studied area were not at risk; however, a groundwater nitrate monitoring system should be implemented.

OBJECTIVE Prenatal exposure to organophosphate pesticides can lead to developmental neurotoxicity. A longitudinal birth cohort was established to investigate pesticide exposures from different agricultural activities. Maternal urinary organophosphate metabolites were measured at 28 weeks of pregnancy (n=86), delivery (n=67) and 2 months postpartum (n=51). METHOD Subjects were interviewed with questionnaires about work, home and behavioral factors potentially associated with pesticide exposures, and spot urine samples were also collected. The urine samples were analyzed for dimethyl phosphate (DMP), diethyl phosphate (DEP), diethyl thiophosphate (DETP) and diethyl dithiophosphate (DEDTP), using gas chromatography-mass spectrometry. RESULTS The urinary DMP and dialkyl phosphate (DAP) concentrations at 28 weeks of pregnancy and delivery were not significantly different, but the DMP and DAP concentrations at 28 weeks of pregnancy and DAP concentrations at delivery were significantly different (p

University of Brescia and Mahidol University of Bangkok developed a project in Phang Nga province (Thailand), the most damaged by 2004 tsunami. In particular, the study, performed between April and May 2006, dealt with the surface and ground water monitoring in Ban Nam Khem village and the experimental evaluation of possible drinking treatment alternatives. The monitoring highlighted that saline content in the tsunami affected area is decreasing but still very high (conductivity presented values up to 2,600 and 6,230 microS/cm in ground and surface water, respectively); hence, advanced and complicated processes such as reverse osmosis should be adopted to treat such water for drinking purposes. Waiting for ground water salinity to assume acceptable values, activities for the reduction of its organic and microbiological contamination will be started. However, it has to be underlined that the diffusion of drinking water to a greater part of population can be obtained only through the realization of new centralised treatment plants and the improvement of existing ones (serving at the moment about 20% of inhabitants).

Floodwater samples (N = 110) collected during the 2011 Bangkok floods were tested for Leptospira using culture and polymerase chain reaction (PCR); 65 samples were PCR-positive for putatively non-pathogenic Leptospira species, 1 sample contained a putatively pathogenic Leptospira, and 6 samples contained Leptospira clustering phylogenetically with the intermediate group. The low prevalence of pathogenic and intermediate Leptospira in floodwater was consistent with the low number of human leptospirosis cases reported to the Bureau of Epidemiology in Thailand. This study provides baseline information on environmental Leptospira in Bangkok together with a set of laboratory tests that could be readily deployed in the event of future flooding.

To determine lead and mercury concentrations in biological samples from nielloware workers, to describe the association between occupational lifestyle, workposition, work environment, behavioral factors, acute and chronic neurological symptoms, and levels of metals in biological samples.A cross-sectional study was conducted by interviewing 45 nielloware workers and 45 matched nonexposed persons living in the municipality of Nakhon Si Thammarat Province, Thailand. Blood and urine samples were collected to determine lead and mercury concentrations by atomic absorption spectrophotometer.The blood lead levels (7.30 microg/dl) and urinary mercury levels (3.30 microg/g creatinine) of the nielloware workers were significantly higher than the control group (p0.001). Income, working environmental conditions, workposition, duration of work, personal protective equipment (PPE) and personal hygiene, had significant associations with blood lead and urinary mercury levels (p0.05). A significant positive correlation was found between income and blood-lead level (r = 0.968, p0.001) and urinary-mercury level (r = 0.661, p = 0.004). The nielloware workers developed acute and chronic symptoms, such as headaches, rash, fatigue, tightness in the chest, loss of consciousness, abnormal tiredness and headache at least once a week and those who developed symptoms had significantly higher heavy metal levels than those who did not at p0.05.The blood lead and urinary mercury levels in nielloware workers were significantly higher than those in the control subjects. The significant associations were found between income, work position, PPE and personal hygiene and blood lead and urinary mercury levels.

Oxidative stress and genetic related to antioxidants could have influence on susceptibility to lead (Pb) toxicity. In this study, we aim to examine the effects of genetic variations of glutathione S-transferase (GST) gene on oxidative stress alterations (by the measurements of malondialdehyde; MDA and glutathione; GSH) among general population. Real-time-PCR with Taqman probes was performed to analyze GSTM1, GSTT1 and GSTP1 Ile105Val. Blood lead and GSH levels were determined by spectrophotometer. MDA level was measured by HPLC with fluorescence detector. Mean blood Pb level in this study group was 4.85 µg/dl (ranged 2.00 and 18.50 µg/dl). Gender, cigarette smoking and alcohol consumption affected significant blood Pb levels. To further investigation, blood Pb levels were calculated into 3 tertiles and statistical results found only in tertile 3. Individuals with the Val/Val allele for GSTP1-105 had higher blood Pb, and MDA levels but lower GSH level as compared to individuals with Ile/Ile genotype (p < 0.05). Similar results were found in GSTM1 deletion, except for the GSH levels. In contrast, no effects of GSTT1 on three parameters were observed. Our findings support consideration of genetic variations of GSH-related genes as the important risk factor for lead toxic effects in the general population with environmental exposure. Key words: Lead, glutathione S-transferase, polymorphisms, glutathione, malondialdehyde.

This paper reports the results of a study conducted in Ban Nam Khem village, the most hit in Thailand by 2004 Indian Ocean tsunami, aimed to evaluate either the actual state and operation of numerous domestic wells present in the village or the quality of drawn groundwater. Data show that most critical chemical-physical parameters are turbidity, total organic carbon and iron, whereas conductivity has greatly decreased in comparison with the February 2005 monitoring campaign. Furthermore, a high faecal contamination related to both constructive and operational deficiencies was detected in most monitored wells; therefore, measures aimed at improving habits in well operation and favouring water domestic treatment are necessary.

This preliminary water quality survey was performed eight weeks after the tsunami hit Phang-Nga Province on 26 December 2004. Water samples collected from the affected area, 10 km parallel to the seaside, were compared with water samples from the control area approximately 4 km from the seaside, which the tsunami waves could not reach. These samples included 18 surface-water samples, 37 well-water samples, and 8 drinking-water samples, which were examined for microbiology and physical-chemical properties. The microbiological examinations focused on enteric bacteria, which were isolated by culture method, while physical-chemical properties comprised on-site testing for pH, salinity, dissolved oxygen (DO), conductivity and total dissolved solids (TDS) by portable electrochemical meter (Sens Ion 156). The results of the microbiological examinations showed that water samples in the affected areas were more contaminated with enteric bacteria than the control area: 45.4% of surface-water samples in the affected area, and 40.0% in the control; 19.0% of well-water samples in the affected area, and 7.7% in the control. All eight drinking-water samples were clear of enteric bacteria. Tests for physical-chemical properties showed that the salinity, pH, conductivity, and TDS of surface-water samples from the affected area were significantly higher than the control. The salinity, conductivity, and TDS of the well-water samples from the affected areas were also significantly greater than those from the control area. The surface and well water in the tsunami-affected area have been changed greatly and need improvement.

The simultaneous determination of urinary trans,trans-muconic acid (t,t-MA) and S-phenylmercapturic acid (S-PMA) was performed by liquid extraction with ethyl acetate and reversed-phase high performance liquid chromatography (RP-HPLC) on a Hypersil-ODS column using the gradient mobile phase of methanol and 0.0012 N perchloric acid and diode array detection at 205 and 264 nm for S-PMA and t,t-MA, respectively. The retention times for t,t-MA and S-PMA were 3.8 and 12.3 minutes, respectively. The recoveries of t,t-MA and S-PMA were97%; between-day precisions were all within 8% RSD (100x SD/mean). The method was applied to analyze the urinary t,t-MA and S-PMA of 59 service station attendants exposed to average benzene concentrations in the air of 0.20+/-0.18 ppm. Significant differences in pre-shift and post-shift urinary t,t-MA between smokers and non-smokers were found.