Study on the correlation of bisphenol A exposure, pro-inflammatory gene expression, and C-reactive protein with potential cardiovascular disease symptoms in young adults.

Bisphenol A (BPA) is a plasticizer used in the manufacture of polycarbonate and epoxy resins. It was found that higher urinary BPA levels are more likely to be associated with coronary artery disease (CVD). In recent years, the increasing incidence of CVD among young people is observed, which may be related with inflammation rather than the traditional triple-H risk factors. BPA is an endocrine-disrupting chemical, and can induce oxidative stress and chronic inflammation since its estrogenic effect. Inflammatory responses could come from the stimulation of IκB kinases (IKKs) by estrogen receptors (ERs). Therefore, this study investigated the association of BPA exposure with the gene expression of pro-inflammatory response (ERs and IKKs), an inflammation biomarker of CVD (C-reactive protein, CRP), and physiologic index potency of CVD development symptoms in young adults. This study divided BPA exposure levels into high and low groups based on the median plasma BPA level (4.34 ng/mL), and found that the high BPA group obviously had higher BMI, blood pressure, plasma CRP levels, and gene expression of ERß and IKKß. BMI and gene expression of IKKß were also positively correlated with plasma CRP secretion. Furthermore, the study subjects with potential CVD development symptoms had the increased levels of BPA (OR 2.10, 95% CI 0.83-5.39), CRP (OR 2.61, 95% CI 1.03-10.6) and IKKß (OR 4.29, 95% CI 1.51-15.6). These results indicated that exposure to BPA is potentially associated with expression of pro-inflammatory genes related to CRP secretion, which may promote the risk of CVD development symptoms in young adults. This study highlighted the possible connection between BPA exposure and CVD development but the mechanism between them needs to be further explored.

PM2.5 exposure of various microenvironments in a community: Characteristics and applications.

While the measurement of particulate matter (PM) with a diameter of less than 2.5 µm (PM2.5) has been conducted for personal exposure assessment, it remains unclear how models that integrate microenvironmental levels with resolved activity and location information predict personal exposure to PM. We comprehensively investigated PM2.5 concentrations in various microenvironments and estimated personal exposure stratified by the microenvironment. A variety of microenvironments (>200 places and locations, divided into 23 components according to indoor, outdoor, and transit modes) in a community were selected to characterize PM2.5 concentrations. Infiltration factors calculated from microenvironmental/central-site station (M/S) monitoring campaigns with time-activity patterns were used to estimate time-weighted exposure to PM2.5 for university students. We evaluated exposures using a four-stage modeling approach and quantified the performance of each component. It was found that the SidePak monitor overestimated the concentration by 3.5 times as compared with the filter-based measurements. Higher mean concentrations of PM2.5 were observed in the Taoist temple and night market microenvironments; in contrast, lower concentrations were observed in air-conditioned offices and car microenvironments. While the exposure model incorporating detailed time-location information and infiltration factors achieved the highest prediction (R2 = 0.49) of personal exposure to PM2.5, the use of indoor, outdoor, and transit components for modeling also generated a consistent result (R2 = 0.44).

PM2.5- and PM10-bound polycyclic aromatic hydrocarbons (PAHs) in the residential area near coal-fired power and steelmaking plants of Taichung City, Taiwan: In vitro-based health risk and source identification.

We investigated spatial and season variations in particle-bound PAH concentrations, identified their potential sources and estimated resultant health risk of activate toxicity pathways in a residential area near coal-fired power and steelmaking plants. Both atmospheric PM2.5 and PM10 samples (n = 94) were simultaneously collected for summer and winter in the Wuqi and Shalu districts of Taichung City, central Taiwan. The principal component analysis (PCA) measure was used to evaluate the sources of particle-bound PAHs. The health risk of PAHs-activated toxicity pathways was estimated through a probabilistic model in cooperation with high-throughput screening (HTS) in vitro assays and measurement data for children and adults. No spatial difference, but significant seasonal variation, in PAH concentrations for PM2.5 (summer = 1.7 ng m-3 and winter = 4.7 ng m-3) and PM10 (summer = 2.1 ng m-3 and winter = 4.8 ng m-3) between two sites was observed, where both sites shared the similar PAH patterns in congener concentrations. PAH contents in the fine mode (PM2.5) of ambient particles are predominant while coarse mode (PM2.5-10) PAHs is negligible. Children with particle-bound PAH exposures have a relatively high health risk of aryl hydrocarbon receptor (AhR)-mediated adverse outcomes than adults, in particular in the winter period, while the activations of Nrf2 and p53 pathways are insignificant. Vehicle emission (67.1%), unburned petroleum (15.0%), steel industry and stationary emission (6.1%), and oil combustion + cooking oil fume (5.6%) associated with PM2.5-bound PAHs were apportioned. The emission from the Taichung coal-fired power plant is rarely attributable to particle-bound PAHs of the study area based on results of spatiotemporal variation of PAHs, wind direction, and source apportionment.

Evaluation of immunomagnetic separation for the detection of Salmonella in surface waters by polymerase chain reaction.

Salmonella spp. is associated with fecal pollution and capable of surviving for long periods in aquatic environments. Instead of the traditional, time-consuming biochemical detection, polymerase chain reaction (PCR) allows rapid identification of Salmonella directly concentrated from water samples. However, prevalence of Salmonella may be underestimated because of the vulnerability of PCR to various environmental chemicals like humic acid, compounded by the fact that various DNA polymerases have different susceptibility to humic acid. Because immunomagnetic separation (IMS) theoretically could isolate Salmonella from other microbes and facilitate removal of aquatic PCR inhibitors of different sizes, this study aims to compare the efficiency of conventional PCR combined with immunomagnetic separation (IMS) for Salmonella detection within a moderately polluted watershed. In our study, the positive rate was increased from 17.6% to 47% with nearly ten-fold improvement in the detection limit. These results suggest the sensitivity of Salmonella detection could be enhanced by IMS, particularly in low quality surface waters. Due to its effects on clearance of aquatic pollutants, IMS may be suitable for most DNA polymerases for Salmonella detection.

Identification and quantification of the Acanthamoeba species and genotypes from reservoirs in Taiwan by molecular techniques.

The occurrence of Acanthamoeba was investigated from 21 main reservoirs of Taiwan with 12 (57.1%) testing positive. Analysis of the 18S rRNA gene PCR product was performed in order to identify the Acanthamoeba isolates. Acanthamoeba spp. concentrations were determined according to TaqMan real-time qPCR. Acanthamoeba genotypes of all isolates were identified T4. The species were categorized to Acanthamoeba culbertsoni, Acanthamoeba polyphaga, Acanthamoeba castellanii and Acanthamoeba hatchetti. The concentration of Acanthamoeba spp. in detected positive reservoir water samples was in the range of 3.0-1.8 × 10(3) cells/L. These results highlight the importance of Acanthamoeba in reservoirs of potential pathogens and its possible role in the spread of bacterial genera with interest in public and environmental health.

Biomonitoring of bisphenol A concentrations in maternal and umbilical cord blood in regard to birth outcomes and adipokine expression: a birth cohort study in Taiwan.

BACKGROUND: Bisphenol A (BPA) is a sealant and flux of plastic materials and has been determined to be an endocrine-disrupting chemical. Prenatal exposure to BPA can lead to substantial adverse effects on fetal growth and development. This study was conducted to assess BPA concentration in pregnant women and umbilical cord blood, and to investigate whether maternal BPA exposure affected fetal outcomes including lower birth weight (LBW), smaller size for gestational age (SGA), and high leptin (HLP) and low adiponectin (LAD) secretion. METHODS: We measured the BPA levels of maternal blood (n = 97) and umbilical cord blood (n = 97) with a high-performance liquid chromatography/UV detector. The protein secretion of leptin and adiponectin were separately determined using enzyme-linked immunosorbent assay. A logistic regression was performed to estimate the effects of maternal exposure to BPA on LBW, SGA, and adverse action of adipokines in newborns. RESULTS: The geometric means of BPA concentration in maternal blood and fetal cord blood were 2.5 ng/ml and 0.5 ng/ml, respectively. Elevated risks of LBW (OR 2.42, 95% confidence interval (CI) 1.72-3.36), SGA (OR 2.01, 95% CI 1.39-3.01), and adverse action of leptin (OR 1.67, 95% CI 1.12-2.25) and adiponectin (OR 1.25, 95% CI 1.52-3.97) were observed in male neonates in the highest quartile of maternal BPA exposure. CONCLUSIONS: Elevated prenatal BPA exposure increased the risk of LBW, SGA, and adverse actions of adipokines in neonates, especially in male infants. These results provide further evidence that maternal exposure is correlated with adverse birth outcomes.

Evaluation of different analysis and identification methods for Salmonella detection in surface drinking water sources.

The standard method for detecting Salmonella generally analyzes food or fecal samples. Salmonella often occur in relatively low concentrations in environmental waters. Therefore, some form of concentration and proliferation may be needed. This study compares three Salmonella analysis methods and develops a new Salmonella detection procedure for use in environmental water samples. The new procedure for Salmonella detection include water concentration, nutrient broth enrichment, selection of Salmonella containing broth by PCR, isolation of Salmonella strains by selective culture plates, detection of possible Salmonella isolate by PCR, and biochemical testing. Serological assay and pulsed-field gel electrophoresis (PFGE) can be used to identify Salmonella serotype and genotype, respectively. This study analyzed 116 raw water samples taken from 18 water plants and belonging to 5 watersheds. Of these 116, 10 water samples (8.6%) taken from 7 water plants and belonging to 4 watersheds were positive for a Salmonella-specific polymerase chain reaction targeting the invA gene. Guided by serological assay results, this study identified 7 cultured Salmonella isolates as Salmonella enterica serovar: Alnaby, Enteritidis, Houten, Montevideo, Newport, Paratyphi B var. Java, and Victoria. These seven Salmonella serovars were identified in clinical cases for the same geographical areas, but only one of them was 100% homologous with clinical cases in the PFGE pattern.

Occurrence of diarrheagenic Escherichia coli genes in raw water of water treatment plants.

PURPOSE: The high incidences of waterborne diseases are frequently associated with diarrheagenic Escherichia coli (DEC). DEC may pose a health risk to people who contact surface water for recreation or domestic use. However, there is no published report on the monitoring of DEC in drinking water sources in Taiwan. In this study, the occurrence of DEC genes in raw water for water treatment plants in Taiwan was investigated. METHOD: Raw water samples were taken from water treatment plants adjacent to the Kaoping River in southern Taiwan. Each water sample was treated with membrane filtration followed by DNA extraction from the concentrate and concentrate enrichment, respectively. The target genes for various DEC strains of genes were identified, including enteroaggregative E. coli (EAEC), enterohemorrhagic E. coli (EHEC), enteroinvasive E. coli (EIEC), enteropathogenic E. coli (EPEC), and enterotoxigenic E. coli (ETEC). RESULTS: Among 55 water samples analyzed, DEC genes were detected in 16 (29.1%) samples. Strain-specific genes for EAEC, EHEC, EIEC, and EPEC were found in the percentages of 3.6%, 10.9%, 9.1%, and 9.1%, respectively. The specific gene for ETEC is not detected in the study. By looking at the presence/absence of specific genes and water sample characteristics, water temperature was found to differ significantly between samples with and without EHEC gene. In addition, pH levels differed significantly for EHEC and EPEC presence/absence genes, and turbidity was significantly different for water with and without EPEC genes. CONCLUSION: DEC genes were detected in 29.1% of the raw water samples in the study location. The potential health threat may be increased if the treatment efficiencies are not properly maintained. Routine monitoring of DEC in drinking water sources should be considered.

Mass, number and surface area concentrations of alpha-quartz exposures of refractory material manufacturing workers.

This study set out to assess the respirable mass, surface area, and number concentrations of the alpha-quartz content particles (C(r-m), C(r-s) and C(r-n)) to which workers were exposed in six different exposure groups, the raw material handling (n=10), crushing (n=12), mixing (n=12), forming (n=10), furnace (n=10), and packaging (n=10), in a refractory material manufacturing plant. For C(r-m), the exposure values in sequence were found as: mixing (68.1 microg/m3)>packaging (55.9 microg/m3)>raw material handling (53.3 microg/m3)>furnace (31.0 microg/m3)>crushing (29.8 microg/m3)>forming (22.4 microg/m3). We also found that ~21.2-68.2% of the above Cr-m exceeded the current TLV-TWA for the alpha-quartz content (50 microg/m3) suggesting a need for initiating control strategies immediately. We further conducted particle size-segregating samplings in four workplaces: crushing (n=3), mixing (n=3), forming (n=3), and furnace (n=3). We found that all resultant particle size distributions shared a quite similar geometric standard deviation (sigma(g); =2.24-2.92), but the process area, associated with higher mechanical energy (i.e., crushing process), contained finer alpha-quartz content particles (mass median aerodynamic diameter; MMAD=3.22 microm) than those areas associated with lower mechanical energy (i.e., mixing, forming, and furnace; MMAD=6.17, 5.95, and 8.92 microm, respectively). These results gave a ratio of C(r-m) in the above four exposure groups (i.e., crushing: mixing: forming: furnace=1.00: 2.30: 0.753: 1.04) which was quite different from those of C(r-s) (1.00: 1.74: 0.654: 0.530) and C(r-n) (1.00: 1.27: 0.572: 0.202). Our results clearly indicate the importance of measuring particle size distributions for assessing workers' free silica exposures.