Environmental policy and legal framework for controlling mercury emissions from stationary sources: a case study in Taiwan

Journal of Material Cycles and Waste Management - In recent years, the Taiwan government partnered with the U.S. Environmental Protection Agency (USEPA) Global Mercury Partnership program to follow...     

A pilot study of citizens' opinions on the Incident Command System in Taiwan

Local residents may have different views on disaster‐response modes depending on their cultural and socioeconomic background. The purpose of this study was to examine Taiwan residents' opinions on the Incident Command System (ICS). We performed a structured survey through face‐to‐face interviews in mudslide‐affected communities. Quantitative analysis showed that the residents exhibited a clear preference for the ICS core‐principle attributes of ‘integrated communications’, ‘transfer of command’ and ‘modular organisation’. By contrast, the residents tended towards a non‐ICS approach for ‘incident action plan’ and ‘manageable span of control’. Qualitative analysis revealed an uncertain attitude towards ‘transfer of command’ and ‘incident action plan’. Community acceptance is important in the promotion of the ICS. A better understanding of residents' preferences should be acquired through a broader community survey, allowing us to understand perspectives on the ICS among different societies and facilitate implementation of the ICS at the basic community level.     

Developmental exposure to decabromodiphenyl ether (PBDE 209): effects on thyroid hormone and hepatic enzyme activity in male mouse offspring

Decabrominated diphenyl ether (PBDE 209) is the second most used brominated flame retardant (BFRs). Many studies have shown that some of the BFRs act as endocrine disruptors via alterations in thyroid hormone homeostasis and affect development. Little is known about the effect of prenatal exposure to PBDE 209 on the development in male offspring. Using a CD-1 mouse model, we attempt to estimate the possible effect of in utero exposure to PBDE 209 on thyroid hormone and hepatic enzymes activities in male offspring. Pregnant mice were administered different doses of PBDE 209 (10, 500, and 1500 mg/kg/day) or corn oil for controls per gavage from gestational days 0-17. In adult male offspring whose mothers had been treated with 1500 mg/kg of PBD 209, hepatic enzyme activity of S9 7-ethoxyresorufin O-deethylase (EROD) was weak but significantly increased (54%). However, no significant changes were observed in S9 4-nitrophenol uridinediphosphate-glucuronosyltransferase (UDPGT) in any of the treatment groups. Serum triiodothyronine (T3) was found to have decreased significantly (ca. 21% both 10 mg/kg and 1500 mg/kg) in offspring, but not thyroxine (T4). Histopathological examination revealed that prenatal exposure of PBDE 209 might be related with cell swelling of hepatocytes in male offspring and there were mild changes in the thyroid glands in 1500 mg/kg group. These data demonstrate that PBDE 209 is likely an endocrine disrupter in male mice following exposure during development. Further studies using environmentally relevant doses are needed for hazard identification.     

Depuration of copper and zinc by green oysters and blue mussels of Taiwan

This paper describes depuration processes of copper and zinc in green oysters (Crassostrea gigas) and in blue mussels (Mytilus smarangdium) collected from an environment with heavy copper contamination, and then transferred to natural clean seawater. Results show that the total loss of copper content per oyster is an exponential function of exposure time for the first 6 days with a depuration rate of 351 microg g(-1) day(-1) and then levels off. During this exponential decrease period approximately 67% of the copper accumulated in green oysters was depurated. However, when the copper contents in the oysters decreased from 2225 +/- 111 microg g(-1) to 344 +/- 18.7 microg g(-1) the depuration rates decreased from 245 microg g(-1) day(-1) to 0.08 microg g(-1) day(-1). This means that green oysters had a 16-fold higher copper depuration rate (351 microg g(-1) day(-1)) than normal oysters (21.5 microg g(-1) day(-1)) for the first 6 days. However, the depuration of accumulated copper and zinc by the mussels was a fast process in natural clean seawater. About 91% of the accumulated copper was lost during the first 6-day period; copper contents declined from 20.2 +/- 3.41 microg g(-1) to 1.80 +/- 0.21 microg g(-1). Only 36% of the accumulated zinc was lost during a depuration period of 6 days. Calculations show that the biological half-lives of copper in green and normal oysters were 11.6 and 25.1 days, respectively. The biological half-lives of zinc in green and normal oysters were 16.7 and 30.1 days, respectively. In spite of the relatively low initial copper content in blue mussels being 20.2 +/- 3.41 microg g(-1), the biological half-life is only 6.40 days. From these results it is important to emphasise that the fastest turnover rate is for copper in blue mussels. However, zinc is more retentive in blue mussels than copper.     

Air pollution associated with cognitive decline by the mediating effects of sleep cycle disruption and changes in brain structure in adults

Environmental Science and Pollution Research - The effects of air pollution on sleep and dementia remain unclear. The objective of this study was to investigate the effects of air pollution on...     

Water-soluble inorganic ions in airborne particulates from the nano to coarse mode: a case study of aerosol episodes in southern region of Taiwan

In 2004, airborne particulate matter (PM) was collected for several aerosol episodes occurring in the southern region of Taiwan. The particulate samples were taken using both a MOUDI (Micro-orifice Uniform Deposit Impactor) and a nano-MOUDI sampler. These particulate samples were analyzed for major water-soluble ionic species with an emphasis to characterize the mass concentrations and distributions of these ions in the ambient ultrafine (PM_0.1, diameter <0.1 μm) and nano mode (PM_nano, diameter <0.056 μm) particles. Particles collected at the sampling site (the Da-Liao station) on the whole exhibited a typical tri-modal size distribution on mass concentration. The mass concentration ratios of PM_nano/PM_2.5, PM_0.1/PM_2.5, and PM₁/PM_2.5 on average were 1.8, 2.9, and 71.0%, respectively. The peak mass concentration appeared in the submicron particle mode (0.1 μm < diameter <1.0 μm). Mass fractions (percentages) of the three major water-soluble ions (nitrate, sulfate, and ammonium) as a group in PM_nano, PM_0.1, PM₁, and PM_2.5 were 18.4, 21.7, 50.0, and 50.7%, respectively. Overall, results from this study supported the notion that secondary aerosols played a significant role in the formation of ambient submicron particulates (PM_0.1−1). Particles smaller than 0.1 μm were essentially basic, whereas those greater than 2.5 μm were neutral or slightly acidic. The neutralization ratio (NR) was close to unity for airborne particles with diameters ranging from 0.18 to 1 μm. The NRs of these airborne particles were found strongly correlated with their sizes, at least for samples taken during the aerosol episodes under study. Insofar as this study is exploratory in nature, as only a small number of particulate samples were used, there appears to be a need for further research into the chemical composition, source contribution, and formation of the nano and ultrafine mode airborne particulates.     

Comparison between urban Toronto PM and selected materials: aerosol characterization using laser ablation/ionization mass spectrometry (LAMS)

Laser ablation/ionization mass spectrometry (LAMS) of particulate matter (PM) was undertaken on-line in order to extend and contrast PM characterization. Qualitative on-line LAMS results for certified materials and Toronto source materials demonstrated the versatility and limitations of the technique. The observation of organic and inorganic components of certified materials verified the proper working condition of the in-house on-line LAMS. Organic and inorganic components of Toronto source materials were also observed with the on-line LAMS. Common components identified from both types of materials were Na, Al, Ca, Fe, and K. Other recognized components were compared with marker elements reported for some common PM emission sources. An in-house off-line LAMS was used to analyze urban Toronto PM deposited on glass substrates, while the on-line LAMS analyzed individual urban Toronto PM particles that were introduced directly into the instrument. Scanning electron microscopy (SEM), X-ray spectrometry and inductively coupled plasma atomic emission spectrometry (ICP-AES) were used for confirmatory purposes. Organic and inorganic components of urban Toronto PM at their typical ng/m3 concentrations were successfully observed in mass spectra using both off-line LAMS and on-line LAMS. Identified ions unique to each analyzed material were compared to identified ions of urban Toronto PM. The ability of LAMS to analyze individual respirable PM particles (viz. < 2 microns), both for inorganic trace elements and for organic components, greatly extended our capability to characterize PM and also to achieve estimates of concentration contributions of each material.     

Comparison of the expectations of residents and rescue providers of community emergency medical response after mudslide disasters

The integration of community resources is critical for emergency response. A thorough understanding of a community's requirements in advance is essential. This study examines communities that suffered mudslide disasters, and discusses expectations of the emergency medical response provided to the community from the perspectives of residents and rescue groups. The questionnaire used in the study was designed to adopt the Likert Scale for quantification purposes. Its content was divided into six categories based on emergency response. Both residents and rescue providers acknowledged that finance and reimbursement were the highest priority. Public information was regarded as the least important by both groups. Significant differences existed between the groups on patient care activities and supportive activities (P = 0.02 and 0.03, respectively), which were more appreciated by residents. We conclude that residents had higher expectations of evacuation, temporary relocation, lodging, food, and sanitary management than the rescue groups.     

Decomposition of SF6 in an RF plasma environment

Sulfur hexafluoride (SFd)-contained gas is a common pollutant emitted during the etching process used in the semiconductor industry. This study demonstrated the application of radio-frequency (RF) plasma in the decomposition of SF6. The decomposition fraction of SF6 [etaSF6 (C(in)-C(out))/C(in) x 100%] and the mole fraction profile of the products were investigated as functions of input power and feed O2/SF6 ratio in an SiO2 reactor. The species detected in both SF6/Ar and SF6/O2/ Ar RF plasmas were SiF4, SO2, Fe2, SO2F2, SOF2, SOF4, S2F10, S2OF10, S2O2F10, and SF4. The results revealed that at 40 W, etaSF6 exceeded 99%, and the reaction products were almost all converted into stable compounds such as SiF4, SO2, and F2 with or without the addition of oxygen. Sulfur oxyfluorides such as SO2F2, SOF2, SOF4, S2OF10, and S2O2F10 were produced only below 40 W. The results of this work can be used to design a plasma/chemical system for online use in a series of a manufacturing process to treat SF6-containing exhaust gases.