Chaur-Tsuen Lo

Particulate-Bound Mercury (Hg[p]) Size Distributions in Central Taiwan

This study focuses on particulate-bound Hg (Hg[p]) composition (ng/g) (defined as ng/g), concentrations (ng/m3) and dry deposition (ng/m2*min) variations for PM18, PM10, PM2.5, and PM1.0. Three characteristic sampling sites collected 1-day ambient suspended particles during November and December 2010 using MOUDI-100S4 samplers. Additionally, Hg(p) size distributions are also characterized. Composition variations of Hg(p) in PM18 were in the order of 0.158 ± 0.055 ng/g (Quan-xing sampling site) > 0.086 ± 0.097 ng/g (Hung-kuang sampling site) > 0.083 ± 0.065 ng/g (Gao-mei sampling site). Further, composition variations of Hg(p) in PM10 were in the order of 0.115 ± 0.038 ng/g (Quan-xing site) > 0.107 ± 0.080 ng/g (Gao-mei site) > 0.103 ± 0.060 ng/g (Hung-kuang site). Composition variations of Hg(p) in PM2.5 were in the order of 0.885 ± 0.423 ng/g (Quan-xing site) > 0.458 ± 0.105 ng/g (Gao-mei site) > 0.372 ± 0.157 ng/g (Hung-kuang site). Finally, composition variations of Hg(p) in PM1.0 were in the order of 0.913 ± 0.441 ng/g (Quan-xing site) > 0.698 ± 0.293 ng/g (Hung-kuang site) > 0.508 ± 0.270 ng/g (Gao-mei site). The Hg(p) size distribution peaked at 1.0 μm at the Quan-xin site, and the lowest average Hg(p) size distribution was 18 μm at the Hung-kung site. The main possible sources for atmospheric particulate-bound mercury Hg(p) were likely from transportation, chemical plant and fossil fuel combustion (Fang et al., 2011). In addition to the above findings, other possible nearby sources at Taichung Thermal Power Plant (TTPP) and Central Taiwan Science Park (CTSP) were: steel industry, electronic industry, plastic industry, chemical industry, basic metal manufacturing, machinery manufacturing, coal products and petroleum. Our sampling sites were in the regions of all of the above sources.

Sources of ambient air particulates and Hg(p) pollutants at Freeway, Industrial, Thermal power plant F.I.T. characteristic sites

This study concerns the concentrations of particulates in ambient air, dry deposited particulates, particulate-bound mercury (Hg(p)), and Hg(p) that is dry deposited in both total suspended particulates and on a dry deposition plate at Long Cyuan Elementary School (LCYES), Lung Ching Elementary School (LCHES), and Long Shan Primary School (LSPS) in Longjing. The LCHES site had the highest particulate Hg(p) concentrations in October and November, and the least dry deposition of particulates in October. The LSPS site had the lowest Hg(p) dry depositions in October. The LCYES site had the lowest particulate and Hg(p) concentrations in November and October, and had the highest dry deposition of particulates and Hg(p) in November and December. These particulates originated from the northwest of Taiwan and were transported by way of mainland China in October. A back trajectory analysis supported this finding. Therefore, particulate concentrations in ambient air were highest in October and the major sources of particulate-bound mercury Hg(p) in ambient air were in mainland China, especially in October and December. Mainland China and Taichung Thermal Power Plant were the main sources of particles and Hg(p) in ambient air.

Atmospheric-particulates-bound mercury Hg(p) study at five characteristic sampling sites in Taiwan.

The main purpose for this study is to observe the seasonal and month variations for particulates-bound mercury Hg(p) in total suspended particulates (TSP) concentration, dry deposition at five characteristic sampling sites during years of 2009–2010 in central Taiwan. The results show that the highest and lowest monthly average particulates-bound mercury Hg(p) concentrations in TSP were occurred in Dec. and Oct. at Gao-mei (wetland), Chang-hua (downtown) and He-mei (residential) sampling site. In addition, the results show that the highest and lowest monthly average particulates-bound mercury Hg(p) dry deposition was occurred in Feb. and Oct. at Quan-xing (industrial) sampling site. This study reflected that the mean highest particulates-bound mercury Hg(p) concentrations in TSP and mean highest particulates-bound mercury Hg(p) dry deposition were occurred at Gao-mei (wetland) and Quan-xing (industrial). However, the mean lowest particulates-bound mercury Hg(p) concentrations in TSP and mean lowest particulates-bound mercury Hg(p) dry deposition were also occurred at Gao-mei (wetland). Regarding seasonal variation, the order of mean-particulates-bound mercury Hg(p) concentrations in TSP in winter and spring were Gao-mei (wetland) > Quan-xing (industrial) > Bei-shi (suburban/coastal) > Chang-hua (downtown) > He-mei (residential). Finally, the order of mean-particulates-bound mercury Hg(p) dry deposition in fall, spring and summer were Quan-xing (industrial) > Bei-shi (suburban/coastal) > Chang-hua (downtown) > He-mei (residential) > Gao-mei (wetland).

Concentrations and analysis of health risks of ambient air metallic elements at Longjing site in central Taiwan

The concentrations of particulates and metallic elements that were bound to total suspended particulates in ambient air at Long Cyuan Elementary School (LCYES), Lung Ching Elementary School (LCHES) and Long Shan Primary School (LSPS) sampling sites in the Longjing area were measured. Significant difference tests were conducted at LSPS, LCYES and LCHES sites. Finally, carcinogenic and non-carcinogenic risk values for LSPS, LCYES and LCHES sites in the Longjing district were evaluated. The results show that the most average particulate and metallic element concentrations were highest in October, November, January, February, March, April, August, and September The average particulate and metallic element concentrations at LCHES were higher than at the other sampling sites. The Concentration Scatter Diagrams reveal the absence of significant variation among the LSPS, LCYES and LCHES sampling sites in the Longjing district. Therefore, these sampling sites are inferred to have similar emission sources. The children and adults inhalation carcinogenic risks which referenced US EPA method were all within acceptable ranges. Non-carcinogenic risks revealed that all metallic elements considered herein were harmless to human health.

Seasonal variations and sources study by way of back trajectories and ANOVA for ambient air pollutants (particulates and metallic elements) within a mixed area at Longjing, central Taiwan: 1-year observation

This study measured the concentrations of particulates and metallic elements in ambient air by using PS-1 sampler (TSP) at Longjing area. And this study focuses on the collection of ambient air particulates, metallic elements, particulate-bound mercury Hg(p), concentrations. In addition, the sources of ambient pollutants by way of back trajectory analysis are found. Moreover, test mean concentration variance differences for metallic elements (PM, Hg(p), Mn, Fe, Zn, Cr, Cu, and Pb) among the four seasons (spring, summer, autumn and winter) through ANOVA are calculated. The result indicates that the average highest particulate concentration occurred in winter season, and the order was winterxa0>xa0springxa0>xa0autumnxa0>xa0summer, and the mostly highest average metallic element (Mn, Fe, Zn, Cr, Cu, Pb) concentrations occurred in autumn. Moreover, the mostly average lowest metallic element concentrations occurred in summer. In addition, the above results of backward trajectories that the major particulate pollutants parcel mainly come from northeastern Taiwan. Moreover, when comparing the results of the first half year to that of the second half year, the they indicated that all metallic elements displayed significant differences in concentrations except those of Hg(p), Mn, Fe, Zn. Finally, metallic element Hg(p) is the only one which showed no significant concentration difference from either seasonal variations or half-year observations.

Annual ambient atmospheric mercury speciation measurement from Longjing, a rural site in Taiwan.

The main purpose of this study was to monitor ambient air particulates and mercury species [RGM, Hg(p), GEM and total mercury] concentrations and dry depositions over rural area at Longjing in central Taiwan during October 2014 to September 2015. In addition, passive air sampler and knife-edge surrogate surface samplers were used to collect the ambient air mercury species concentrations and dry depositions, respectively, in this study. Moreover, direct mercury analyzer was directly used to detect the mercury Hg(p) and RGM concentrations. The result indicated that: (1) The average highest RGM, Hg(p), GEM and total mercury concentrations, and dry depositions were observed in January, prevailing dust storm occurred in winter season was the possible major reason responsible for the above findings. (2) The highest average RGM, Hg(p), GEM and total mercury concentrations, dry depositions and velocities were occurred in winter. This is because that China is the largest atmospheric mercury (Hg) emitter in the world. Its Hg emissions and environmental impacts need to be evaluated. (3) The results indicated that the total mercury ratios of Kaohsiung to that of this study were 5.61. This is because that Kaohsiung has the largest industry density (~60xa0%) in Taiwan. (4) the USA showed average lower mercury species concentrations when compared to those of the other world countries. The average ratios of China/USA values were 89, 76 and 160 for total mercury, RGM and Hg(p), respectively, during the years of 2000–2012.

Particulate-bound mercury (PBM) in stems and leaves of several crops (white cabbage, Peking cabbage, and chili) at a farmland site in Taiwan

ABSTRACT This study analyzes the particulate-bound mercury (PBM) contents of two parts (leaf and stem) of different crops (white cabbage, Peking cabbage, and chili) at a sampling site in the coastal zone in the Taichung area from October 7 to 15, 2014. A direct mercury analyzer (DMA-80) was used to measure mercury content. The Mann-Whitney rank sum test was utilized to determine the mean differences between the PBM in two parts of various crops (white cabbage leaf, white cabbage stem, Peking cabbage leaf, Peking cabbage stem, and chili) at the Long-Jing sampling site. The results indicated the following: 1) The average mercury content was lowest in the Peking cabbage stem. The ratio of the mercury content in the stem to that in the leaf of the white cabbage was 5 and that of Peking cabbage was 3.5.2) No significant difference was observed between median mercury content in white cabbage leaf and Peking cabbage leaf, white cabbage stem and Peking cabbage stem, and Peking cabbage leaf and chili. 3) The average PBM contents were both the lowest (Huabei Plain) and the highest in Hg in China. 4) The ratio of average PBM content of white cabbage leaf in this study was as high as 981.

Ambient Air Particulates Bound Mercury Hg(p) Study Among Four Crops (Rice, White Cabbage, Arden Lettuce, and Gynura) at a Characteristic Sampling Site

The main purpose of this study was to monitor ambient air particulates and particulate-bound Hg (Hg[p]) compositions in different crops in the coastal zone in the Taichung, Taiwan, area at a sampling site during 2013 October to 2013 December. In addition, a direct mercury analyzer (DMA-80) was used to directly detect the concentration with measured results by the regression equation of Hg in the ambient air. The results indicated that: 1) the mean values of ambient air Hg(p) compositions in rice displayed no significant differences for weeks one, two, and three versus those of the other crops (white cabbage, Arden lettuce, and Gynura procumbens); 2) for white cabbage, the higher the humidity, the lower the average ambient air Hg(p) compositions that were obtained, a phenomenon that was also reflected on the crops of white cabbage and G. procumbens; 3) Arden lettuce displayed no significant differences in the leaf Hg(p) compositions during weeks one, two, and three; however, the stem portions displayed significant differences in Hg(p) compositions during weeks two and three; and 4) the Spearman statistical method showed the mean differences for ambient air Hg(p) at the Long-jing sampling site (coastal regions) with four different crops (rice, white cabbage, Arden lettuce, and Gynura) in central Taiwan. The results further revealed no significant differences in mean values.

Comparisons of particulate-bound mercury (PBM) compositions in soil and vegetation at a traffic site

ABSTRACT This investigation analyzes the particulate-bound mercury (PBM) compositions in soil and vegetation at a traffic sampling site in Taichung, Taiwan, during a sampling period from October to December, 2015. A direct mercury analyzer (DMA-80) was used to measure the particulate-bound mercury (PBM). A T-test was conducted to determine the mean differences between the PBM composition in soil and that in vegetation at the site. The results indicate that 1) the mean particulate-bound mercury compositions in soil and vegetation were the lowest in November, when the (mean OR average) wind speed was the highest (4.1 m/s); 2) Particulate-bound mercury compositions (PBM) in both soil and vegetation correlated weakly with temperature, humidity and wind speed; 3) T-test statistical results denoted that the PBM compositions did not significantly differ between soil and vegetation in the three-month sampling period.

PM2.5 particulates and particulate-bound mercury Hg(p) concentrations in a mixed urban, residential, traffic-heavy, and industrial site

ABSTRACT This study analyzes the concentrations of ambient fine particulates and particulate-bound mercury Hg(p) at sampling sites in various areas in central Taiwan during a sampling period from January to April 2015. A Wilbur PM2.5 sampler was used to collect PM2.5 from ambient air and a DMA-80 direct mercury analyzer was used to analyze the concentration of mercury Hg(p) that was attached to PM2.5. The results show that the mean PM2.5 and Hg(p) concentrations were highest in March. The Chinese Lantern Festival and the “Faithful Pilgrims Who Follow Matsu through Taiwan” are hosted in this month. Many fireworks and firecrackers are let off at this time, releasing particulate matter into the atmosphere, increasing the concentrations of atmospheric particulate pollutants. The highest average PM2.5 concentrations were measured in January. A dust storm in Mainland China may have been responsible for this result. February saw the lowest mean PM2.5 recorded in this study, possibly because commercial districts and factories were closed in February for Chinese Lunar New Year. April saw the highest mean wind speed, diluting particulate pollutants in ambient air.