Health impact assessment of PM2.5 from a planned coal-fired power plant in Taiwan.

PURPOSE: To investigate the impact of a planned coal-fired power plant (CFPPT) in Shenao on air quality and health at subnational levels in Taiwan. METHODS: We applied the Gaussian trajectory transfer-coefficient (GTx) model to estimate annual average PM2.5 (particulate matter with aerodynamic diameter less than 2.5 µm) increments in 19 Taiwanese cities and counties caused by CFPPT operation. A population health risk assessment was performed by incorporating evidence of the health effects of PM2.5 provided by prospective studies and estimating long-term PM2.5 exposure. Additionally, we considered ischemic heart disease, stroke, lung cancer, and chronic obstruct pulmonary disease as the primary outcomes. The population-attributable fraction was used to estimate the county-level mortality burden attributable to CFPPT-generated PM2.5 in 2025. RESULTS: The estimated annual PM2.5 increments ranged from 0.004 µg/m3 (Taitung County) to 0.28 µg/m3 (Hsinchu County) due to the Shenao CFPPT. The total and premature deaths attributable to PM2.5 from Shenao CFPPT operation in Taiwan during 2025-2040 would be 576 (95% confidence interval [CI]: 537-619) and 145 (95% CI: 136-155), respectively. Notably, we estimated 198 (95% CI: 169-234) deaths and 58 (95% CI: 51-66) premature deaths, respectively, in New Taipei City, which accounted for over a quarter of the total deaths. Overall, the mortality rate attributable to the Shenao CFPPT in Taiwan was 6 per 10,000. CONCLUSION: A scientific approach should be adopted for assessing the impacts of CFPPT operation on population health, which can serve as a valuable policymaking reference for the government.

Increased cancer incidence of Changhua residents living in Taisi Village north to the No. 6 Naphtha Cracking Complex.

BACKGROUND/PURPOSE: Cancer risks of residents living north to the No. 6 Naphtha Cracking Complex has not been studied before. METHODS: Our study subjects were recruited in 2014-16 from three zones north to the No. 6 Naphtha Cracking Complex, which included 229 participants from the Taisi Village (average 5.5 km from the complex), 1333 participants from the other 14 villages in Dacheng Township (9.2 km), and 372 participants from the Zhutang Township (19.9 km). Their occurrence of cancer in years-post-complex-operation (YPO) was defined by having a new cancer recorded (ICD-9: 140-208) in National Health Insurance Research Database since 1999. Poisson regression was conducted to compare incidence rate ratio among three zones in 10-16 YPO. RESULTS: We found that all-cause cancer incidence of 10-16 YPO (per 1,000 person-years) in Taisi Village (8.44) was higher than that in Dacheng (3.42) and Zhutang (2.72). Taisi residents had significantly higher concentrations of V, Cr, Mn, Ni, Cu, As, Cd, and Tl than Dacheng and Zhutang residents. The all-cause cancer incidence rate ratio between 10-16 and 0-9 YPO was 8.44 for Taisi residents. All-cause cancer incidence rate of Taisi residents was 2.55 times higher than Dacheng residents (95% CI: 1.89-3.45) and 2.43 times higher than Zhutang residents (95% CI: 1.54-3.84) in 10-16 YPO. CONCLUSION: We conclude that all-cause cancer risk was significantly increased for Taisi residents living near the No. 6 Naphtha Cracking Complex for 10-16 years after the complex began operating.

Source apportionment of mass concentration and inhalation risk with long-term ambient PCDD/Fs measurements in an urban area.

This study applies a receptor model to quantify source contributions to ambient concentration of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and inhalation cancer risk in Taipei from 2003 through 2009. Seventeen PCDD/F congeners were used in the effective variance solution to the Chemical Mass Balance equations to estimate source-specific mass contributions and inhalation risks. The average total PCDD/F concentration was 0.611pg/Nm(3) (0.036pg I-TEQ/Nm(3)). Traffic emissions contributed the most to the PCDD/F concentration (55.7%), followed by waste incinerators (18.6%) and joss stick burning (9.6%). For the inhalation cancer risk, the average was 1.1×10(-6) with traffic, waste incinerators, and joss paper burning as the main contributors (67.3%, 19.4%, and 6.3%, respectively). The mass and risk contributions of waste incinerators decreased significantly from 2003 to 2009 and were higher at downwind sites than at upwind sites. Reducing PCDD/F emissions from traffic and waste incinerators would provide the greatest health benefit. Policies that reduce the uncontrolled burning of joss stick and joss paper also need to be implemented.

Probabilistic framework for assessing the arsenic exposure risk from cooked fish consumption.

Geogenic arsenic (As) contamination of groundwater is a major ecological and human health problem in southwestern and northeastern coastal areas of Taiwan. Here, we present a probabilistic framework for assessing the human health risks from consuming raw and cooked fish that were cultured in groundwater As-contaminated ponds in Taiwan by linking a physiologically based pharmacokinetics model and a Weibull dose-response model. Results indicate that As levels in baked, fried, and grilled fish were higher than those of raw fish. Frying resulted in the greatest increase in As concentration, followed by grilling, with baking affecting the As concentration the least. Simulation results show that, following consumption of baked As-contaminated fish, the health risk to humans is <10(-6) excess bladder cancer risk level for lifetime exposure; as the incidence ratios of liver and lung cancers are generally acceptable at risk ranging from 10(-6) to 10(-4), the consumption of baked As-contaminated fish is unlikely to pose a significant risk to human health. However, contaminated fish cooked by frying resulted in significant health risks, showing the highest cumulative incidence ratios of liver cancer. We also show that males have higher cumulative incidence ratio of liver cancer than females. We found that although cooking resulted in an increase for As levels in As-contaminated fish, the risk to human health of consuming baked fish is nevertheless acceptable. We suggest the adoption of baking as a cooking method and warn against frying As-contaminated fish. We conclude that the concentration of contaminants after cooking should be taken into consideration when assessing the risk to human health.

Lung cancer risk in relation to traffic-related nano/ultrafine particle-bound PAHs exposure: a preliminary probabilistic assessment.

Exposures to carcinogenic polycyclic aromatic hydrocarbons (PAHs) have been linked to human lung cancer. The purpose of this study was to assess lung cancer risk caused by inhalation exposure to nano/ultrafine particle-bound PAHs at the population level in Taiwan appraised with recent published data. A human respiratory tract model was linked with a physiologically based pharmacokinetic model to estimate deposition fraction and internal organic-specific PAHs doses. A probabilistic risk assessment framework was developed to estimate potential lung cancer risk. We reanalyzed particle size distribution, total-PAHs, particle-bound benzo(a)pyrene (B[a]P) and PM concentrations. A dose-response profile describing the relationships between external B[a]P concentration and lung cancer risk response was constructed based on population attributable fraction (PAF). We found that 90% probability lung cancer risks ranged from 10(-5) to 10(-4) for traffic-related nano and ultrafine particle-bound PAHs, indicating a potential lung cancer risk. The particle size-specific PAF-based excess annual lung cancer incidence rate due to PAHs exposure was estimated to be less than 1 per 100,000 population, indicating a mild risk factor for lung cancer. We concluded that probabilistic risk assessment linked PAF for limiting cumulative PAHs emissions to reduce lung cancer risk plays a prominent role in future government risk assessment program.

Assessing the potential exposure risk and control for airborne titanium dioxide and carbon black nanoparticles in the workplace.

PURPOSE: This study assessed the potential exposure risks for workers in the workplace exposed to airborne titanium dioxide nanoparticles (TiO(2)-NPs) and carbon black nanoparticles (CB-NPs). The risk management control strategies were also developed for the NP engineering workplace. METHODS: The method used in this study was based on the integrated multiple-path particle dosimetry model to estimate the cumulative dose of nanoparticles (NPs) in the human lung. The study then analyzed toxicological effects such as pulmonary cytotoxicity and inflammation and evaluated the health risk associated with exposure to NPs in the workplace. Risk control measures such as the use of ventilating systems and N95 respirator protection are also discussed. RESULTS AND DISCUSSION: This study found that: (1) the cumulative dose of CB-NPs was greater than that of TiO(2)-NPs in human lungs; (2) there is a potential health risk to workers exposed to TiO(2)-NPs and CB-NPs in the absence of control measures in the workplace, with higher health risks associated with CB-NPs than TiO(2)-NPs; and (3) the use of a ventilating system and an N95 respirator offers greater protection in the workplace and significantly reduces the health risks associated with NP exposure. CONCLUSION: The present risk management control strategy suggests that the most effective way to reduce airborne NPs is to incorporate the use of a ventilating system combined with N95 respirator protection. This will enable the concentrations of TiO(2)-NPs and CB-NPs to be reduced to acceptable exposure levels.

Risk-based probabilistic approach to assess the impact of false mussel invasions on farmed hard clams.

The purpose of this article is to provide a risk-based predictive model to assess the impact of false mussel Mytilopsis sallei invasions on hard clam Meretrix lusoria farms in the southwestern region of Taiwan. The actual spread of invasive false mussel was predicted by using analytical models based on advection-diffusion and gravity models. The proportion of hard clam colonized and infestation by false mussel were used to characterize risk estimates. A mortality model was parameterized to assess hard clam mortality risk characterized by false mussel density and infestation intensity. The published data were reanalyzed to parameterize a predictive threshold model described by a cumulative Weibull distribution function that can be used to estimate the exceeding thresholds of proportion of hard clam colonized and infestation. Results indicated that the infestation thresholds were 2-17 ind clam(-1) for adult hard clams, whereas 4 ind clam(-1) for nursery hard clams. The average colonization thresholds were estimated to be 81-89% for cultivated and nursery hard clam farms, respectively. Our results indicated that false mussel density and infestation, which caused 50% hard clam mortality, were estimated to be 2,812 ind m(-2) and 31 ind clam(-1), respectively. This study further indicated that hard clam farms that are close to the coastal area have at least 50% probability for 43% mortality caused by infestation. This study highlighted that a probabilistic risk-based framework characterized by probability distributions and risk curves is an effective representation of scientific assessments for farmed hard clam in response to the nonnative false mussel invasion.

Assessing hazardous risks of human exposure to temple airborne polycyclic aromatic hydrocarbons.

We proposed an integrated probabilistic risk assessment framework based on reported data to quantify human health risks of temple goers/workers to airborne polycyclic aromatic hydrocarbons (PAHs) from incense burning in typical Taiwanese temples. The framework probabilistically integrates exposure, human respiratory tract, and incremental lifetime cancer risk (ILCR) models to quantitatively estimate size-dependent PAHs exposure in human lung regions and cancer risks for temple goers (moderate and high exposures) and temple workers (extreme exposure). Our results show that the ILCRs are greater than the acceptable level of 10(-6) for extreme and high exposure groups through inhalation route. The result also indicates that the higher ILCRs (10(-6) to 10(-4)) are found in ingestion and dermal contact routes for temple goers/workers. For personal extreme exposure to carcinogenic PAH in the temple, 95% probability total ILCR (TILCR) (9.87 x 10(-4) to 1.13 x 10(-3)) is much greater than the range of 10(-6) to 10(-4), indicating high potential health risk to temple workers. For temple goers with high and moderate exposure groups, however, the 95% probability TILCRs were estimated from 6.44 x 10(-5) to 7.50 x 10(-5) and 5.75 x 10(-6) to 6.99 x 10(-6), respectively. This study successfully offers a scientific basis for risk analysis due to incense burning to enhance broad risk management strategies for temple indoor air quality.

Model-based assessment for human inhalation exposure risk to airborne nano/fine titanium dioxide particles.

This paper proposed a model-based approach to assess inhalation risk levels to manufacturing workers in titanium dioxide (TiO2) production factories. The risk level-based analytical schemes were present for investigations of job-related airborne nano/fine TiO2 dust exposures. A Hill model was used to reconstruct dose-response function based on data from rats exposed by chronic inhalation to poorly soluble fine and nanosized particles. A physiologically based lung model was used to predict surface area-based TiO2 burdens in alveolar surface and interstitial granuloma, respectively. The exposure effect was characterized by polymorphonuclear leukocytes (PMN) elevation effect on lung surface and lung tumor proportion on interstitium. Combining laboratory, field, and modeling results, two major findings were proposed to the current epidemiological studies: (i) the estimated median effective surface area-based TiO2 lung burden (EC50) for PMN elevation effect is 0.11 m2 g(-1) lung (95% CI: 0.04-0.2) and EC50 for lung tumor proportion is 1.15 m2 g(-1) lung (95% CI: 0.65-1.89) and (ii) the estimates of risk curves are the pivotal results for public policy. The results demonstrate that packers in US factories have approximately 85.77 fold (95% CI: 63.84-94.33) of standard PMN counts of 10(6), whereas 86.97 fold (95% CI: 66.72-94.54) for surface treatment workers in EU factories at risk of 0.5. The lung had approximately 45% (95% CI: 15%-54%) tumor proportion for packers in US factories, whereas 48.19% (95% CI: 20-53.79%) for surface treatment workers in EU factories at risk of 0.5. The findings point out that dry/wet treatment and ore handlers in US and maintenance mechanics in EU factories were unlikely to pose substantial lung cancer risks.