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Background: There is accumulating epidemiologic evidence that exposure to traffic-related air pollutants, including particulate matter (PM) and polyaromatic hydro carbons (PAHs), plays a role in etiology and prognosis of a large scale of illnesses, although the role of specific causal agents and underlying mechanisms for different health outcomes remains unknown. Objective: Our general objective was to assess the relations between personal exposure to traffic exhausts, in particular ambient PM2.5 and PAHs, and the occurrence of DNA strand breaks by applying personal monitoring of PM and biomarkers of exposure (urinary 1-hydroxypyrene-glucuronide, 1-OHPG) and effect (urinary 8-hydroxydeoxyguanosine, 8-OHdG and DNA strand breaks). Methods: We recruited 91 traffic conductors and 53 indoor office workers between May 2009 and June 2011 in Taipei City, Taiwan. We used PM2.5 personal samplers to collect breathing-zone particulate PAHs samples. Spot urine and blood samples after work shift of 2 consecutive days were analyzed for 1-OHPG, 8-OHdG and DNA strand breaks, respectively. Statistical methods included linear regression and mixed models. Results: Urinary 8-OHdG levels and the occurrence of DNA strand breaks in traffic conductors significantly exceeded those in indoor office workers in mixed models. Particulate PAHs levels showed a positive association with urinary 1-OHPG in the regression model (β = 0.056, p = 0.01). Urinary 1-OHPG levels were significantly associated with urinary 8-OHdG levels in the mixed model (β = 0.101, p = 0.023). Our results provide evidence that exposure to fine particulates causes DNA damage. Further, particulate PAHs could be biologically active constituents of PM2.5 with reference to the induction of oxidative DNA damages. [ABSTRACT FROM AUTHOR]

Background: Previous follow-up studies of repeated self-harm show that the cumulative risk of repeated self-harm within one year is 5.7%-15%, with females at greatest risk. However, relatively few studies have focused on the Far East. The objective of this study was to calculate the cumulative risk of repeated self-harm over different lengths of follow-up time (3 months, 6 months, and 1-8 years), to determine factors influencing repeated self-harm and to explore the interaction between gender and self-harm methods. Methods: We used self-harm patient who hospitalized due to first-time self-harm between 2000 and 2007 from 1,230 hospitals in Taiwan. Hospitalization for repeated self-harm among members of this cohort was tracked after 3 months, 6 months, and 1-8 years. Tracking continued until December 31, 2008. We analyzed the cumulative risk and risk factors of repeated self-harm by using negative binomial regression. Results: Of the 39,875 individual study samples, 3,388 individuals (8.50%) were found to have repeatedly self-harmed. The cumulative risk of repeated self-harm within three months was 7.19% and within one year was 8%. Within 8 years, it was 8.70%. Females were more likely to repeatedly self-harm than males (RR = 1.21, 95% CI = 1.15-1.76). The main method of self-harm was solid or liquid substances (RR = 1.88, 95% CI = 1.23-2.04) or cutting or piercing (RR = 1.36, 95% CI = 1.02-1.82), and in patients with psychiatric disorders were more likely to self-harm (RR = 1.61, 95% CI = 1.48-1.75). Conclusions: The key time for intervention for repeated self-harm is within three months. Appropriate prevention programs should be developed based on gender differences. [ABSTRACT FROM AUTHOR]

The article focuses on a study conducted to assess occupational exposure to fine particulate matter among toll station workers in Taipei, Taiwan, who constitute a very high exposure group. The authors conducted a 10-day longitudinal study at a highway toll station in the Taipei metropolitan area of Taiwan. The source population consisted of all workers in the selected toll station, located on the First Highway 10 km south of Taipei City. The authors applied both direct and indirect exposure assessment approaches. Both approaches focused on fine particulate matter concentrations in the booths. Measurements for direct exposure assessment were available for only part of the study population and time, and therefore a combined direct and indirect approach was applied to achieve maximal exposure information. Results of the study showed clearly that besides traffic density, the type of vehicle is crucial additional information. Buses and trucks contributed more strongly per vehicle than cars.

The article presents the findings of a study that evaluated the viability of urinary 1-hydroxypyreneglucuronide (1-OHP-gluc) as a potential biomarker of exposure to various traffic exhausts. Subjects were 47 female highway toll-station workers and 27 female office workers in training for toll-station employment in Taipei, Taiwan. Immediately following her work shift, each worker provided a urine sample in a brown polyethylene 500-ml container labeled with the subject's identification number and date and time of collection. The researchers studied both dichotomous and continuous determinants of exposure. The findings indicate that urinary 1-OHP-gluc concentrations reflect exposure to exhausts from various vehicles. Female nonsmoker toll workers who were exposed to a potent source of traffic pollutants had, on average, 60% higher levels of urinary 1- OHP-gluc following their work shifts than the reference female office employees in training to be toll workers. There was a linear association between daily occupational exposure to passenger cars and post-shift levels of urinary 1-OHP-gluc. Smoking was also a strong determinant of urinary 1-OHP-gluc concentration.

Presents a study determining the relationship between concentration of pyrene and aerosol size distribution in traffic exhausts in Taipei, Taiwan. Use of gas chromatography and mass spectrometry to analyze several polycyclic aromatic hydrocarbons; Determination of higher pyrene concentrations in truck and bus emissions compared to car emissions; Consideration of aerodynamic particle size.

Introduction: Pesticide poisoning is an important public health problem worldwide. The study aimed to determine the risk of all-cause and cause-specific inpatient mortality and to identify prognostic factors for inpatient mortality associated with unintentional insecticide and herbicide pesticide poisonings. Methods: We performed a retrospective cohort study of 3,986 inpatients recruited at hospitalization between 1999 and 2008 in Taiwan. We used the International Classification of Disease, 9th ed., Clinical Modification external causes of injury codes to classify poisoning agents into accidental poisoning by insecticides and herbicides. Comparisons in mortality rates were made between insecticide poisoning patients and herbicide poisoning patients by using the Cox proportional hazards models to estimate multivariable-adjusted hazard ratios (HRs) and their 95% confidence intervals (CIs). Results: There were 168 deaths during 21,583 person-days of follow-up evaluation (7.8 per 1,000 person-days). The major causes of mortality for insecticide poisonings were the toxic effect of organophosphate and coma, and the major causes of mortality for herbicide poisonings were the toxic effect of other pesticides and the toxic effect of organophosphate. The mortality for herbicide exposure was fourfold higher than that for insecticide exposure. The factors associated with inpatient mortality were herbicide poisonings (HR = 4.58, 95% CI 3.29 to 6.37) and receiving mechanical ventilation treatment (HR = 3.85, 95% CI 2.73 to 5.42). Conclusions: We demonstrated that herbicides stand out as the dominant agent for poisoning-related fatalities. The control of and limiting access to herbicide agents and developing appropriate therapeutic regimens, including emergency care, should be priorities. [ABSTRACT FROM AUTHOR]

Purpose: To assess changes in oxidative DNA damage and lung function amongst a group of foundry workers resulting from an engineering intervention to reduce air respirable dust in their working environment. Methods: We studied all 22 workers recruited from a typical small Taiwanese iron foundry plant before and 3 months after improvements to air exhaust control. The effectiveness of the air exhaust intervention in reducing respirable dust and SiO was determined by personal breathing-zone air sampling. Initial baseline biomarker measurements were taken of lung function and urinary 8-hydroxy-deoxyguanosine (8-OHdG) in all of the workers, with follow-up measurements taken 3 months after the engineering control was put in place. Generalized estimating equations were used to assess the effect of the intervention on lung function and oxidative DNA damage. Results: Following the intervention, respirable dust density decreased from 2.87 ± 1.38 mg/m to 1.60 ± 0.70 mg/m ( p = 0.07), and SiO concentration decreased from 0.43 ± 0.25 mg/m to 0.18 ± 0.11 mg/m ( p < 0.05). Compared to initial baseline, significant improvements were found in lung function (FVC, FEV1, FVC%pred and FEV1%pred) amongst the workers after the engineering intervention. A significant increase in concentration of urinary 8-OHdG was observed after the engineering intervention in smokers, but not in non-smokers. Conclusions: These findings indicate that reductions in workplace respirable dust and SiO concentration can result in improved lung function amongst foundry workers. [ABSTRACT FROM AUTHOR]

In this study, 32 booth attendants (the exposure group) and 21 in pre-job training to become booth attendants (the reference group) were randomly selected from a highway toll station. Personal PAH samplings were conducted on the exposure group on each day during the studied workweek. Pre-shift urinary 1-hydroxylpyrene levels (1-OHP) were measured on the first day of the workweek (BM[SUBpre]) for both the exposure and reference groups, but the post-shift 1-OHP levels were measured on the last day of the workweek (BM[SUBpost]) only for the exposure group. For the exposure group, we found that their mean total PAH exposure level (C[SUBtotal] PAHs) was 11 400 ng/m[SUP3] and that their mean BM[SUBpost] was significantly higher than their mean BM[SUBpre] (= 3.02 and 0.910 μmol of 1-OHP/mol of creatinine, respectively). In addition, the mean BM[SUBpre] for the exposure group were higher than that for the reference group (= 0.410 μmol of 1-OHP/mol of creatinine). The above results suggest that vehicle exhaust significantly affects the booth attendants' 1-OHP levels. None of the three personal factors (age, work experience, and smoking habit), except for C[SUBtotal] PAHs, had a significant effect on predicting booth attendants' BM[SUBinc] levels (=BM[SUBpost]-BM[SUBpre]) (R[SUP2] = 0.57). The above results suggest that urinary 1-OHP could be a suitable biomarker for characterizing workers' PAH exposures. Similarly, we found that none of the three personal characteristics, except for the involved vehicle flow rates and vehicle types, had a significant effect on predicting booth attendants' BM[SUBinc] levels (R[SUP2] = 0.60). The above result suggests that the traffic densities of various traffic types could be a suitable surrogate indicator for assessing workers' PAH exposures. [ABSTRACT FROM AUTHOR]

The present study was set out to assess the contents of polycyclic aromatic hydrocarbons (PAHs) in three types of tollbooths at a highway toll station via direct and indirect approaches. Direct sampling results show that no significant difference could be found in the PAH homologue distributions for samples collected from the car lane/ticketpayment and car lane/cash-payment tollbooths, but both were significantly different from that for the bus/ truck lane tollbooth. The above results could be due to the former two types of tollbooths that were designed for the same type of traffic (i.e., cars and vans), but the latter was designed for a different type of traffic (i.e., buses and trucks). For any given type of tollbooth, the total-PAH content (C[sub TotaI-PAHs]) found during the day Shift (= 9370-15500 ng/m³) were not significantly different from that found during the night shift (= 9550-14900 ng/m³), but both were significantly higher than that found during the latenight shift (= 5560-11100 ng/m³). During any given work shift, we found C[sub Total-PAHs] for the three types of tollbooths as the following: bus/truck lane (= 11100-15500 ng/m³) > car lane/ticket-payment (= 7260-13500 ng/m³) > car lane/ cash-payment (= 5560-9550 ng/m³). After conducting multivariate regression analyses, we found that none of the three environmental factors (i.e., wind speed, temperature, and relative humidity), except for the vehicle flow rate (Q[sub Vehicle]), had a significant effect on C[sub TotaI-PAHs] for any given type of tollbooth. Considering directly measuring PAH contents was labor-consuming and costly, and the above results suggest the possibility of using Q[sub Vehicle] to predict C[sub Total-PAHs] for any given type of tollbooth. After conducting simple linear regression analyses, we found that (1) all resultant regression coefficients were found with positive values indicating that an increase in the Q[sub Vehicle] would lead to an... [ABSTRACT FROM AUTHOR]