Search

This study analyzed the rainwater collected in Central Taiwan during the near typhoon period. Mercury (Hg) was analyzed and the Hg volume weighted mean concentrations (VWM) and wet depositions were calculated during the near typhoon period. In addition, the Hg wet depositions, VWM and precipitation values obtained were compared with Plum rain and regular precipitation periods. The relationship between wet Hg depositions, VWM and precipitations were also discussed. Wet Hg depositions, VWM and precipitations were also compared with the precipitation collected from other parts of the world during 2009 to 2021. The results indicated that the precipitations, VWM and wet Hg depositions in the near typhoon period were 152.5 mm, 0.82 ng/L, and 0.29 μg/m2, respectively. The Hg precipitation ratio values of this study to the plum rain and regular precipitation periods were 3.70 and 6.63, respectively. The Hg VWM ratios values of this study to the plum rain and regular precipitation periods were 12,852.56 and 1.56, respectively. Moreover, the wet Hg deposition ratios values of this study to the plum rain and regular precipitation periods (near typhoon period) were 105.97 and 9.90, respectively. The results further indicated that the Hg VWM and wet depositions obtained in the near typhoon period showed the lowest values when compared with plum rain and regular precipitations periods. Compared with Hg(p) VWM and Fw values obtained from plum season, regular precipitation, this study (typhoon period) demonstrated it has the average lowest VWM and Fw values among these three sampling periods. The correlation coefficient of precipitation and the mercury wet deposition was 0.72051 which was significant in this study. The correlation coefficient for the VWM of mercury was 0.0826 which displayed insignificant relationship in this study. Finally, when comparing the Hg VWM, wet deposition and precipitation values from various studies, the results further indicated that the near typhoon period has the lowest average Hg VWM, wet deposition and precipitation values. [ABSTRACT FROM AUTHOR]

The concentrations of ambient air particulates of various sizes (PM1, PM2.5, PM6.25, PM10 and PM18) were measured using a MOUDI sampler at an agricultural sampling site in central Taiwan from January to September, 2020. The concentrations of particulate-bound mercury Hg(p) that were attached to particulates of various sizes (PM1, PM2.5, PM6.25, PM10 and PM18)) were analyzed using a Direct Mercury Analyzer (DMA-80). The results revealed that the mean particulate and Hg(p) concentrations associated with PM18, PM10, PM6.25, PM2.5 and the back filter were all highest in autumn and winter. The mean mass median diameter (m.m.d.) value for ambient air particulates was highest in the summer and lowest for Hg(p). The mean m.m.d. value for ambient air Hg(p) was highest in the winter and lowest for ambient air particulates. The northeast monsoon prevails in the winter season of Taiwan. Thus, The sources of particulates and Hg(p) pollutants might came from the northeast side of Taiwan - especially in spring and winter seasons. Thus, ambient air particulate concentrations are higher in the winter than in the spring. However, ambient air particulate-bound mercury Hg(p) tended to be associated more with coarse particulates than with other particulates. Finally, Hg(p) concentrations in Taiwan have increased over the last 15 years. Reducing atmospheric Hg(p) concentrations has become an important environmental goal in all countries - especially those in Asia. [ABSTRACT FROM AUTHOR]

This study collected ambient air total suspended particle (TSP) concentrations and dry depositions at Taichung Science Park sampling site. The metallic elements concentrations and dry depositions were analyzed. The possible pollutant sources are discussed in this study. In addition, this study used the principal component analysis method to find metallic element sources and their transportation pathway and distributions at Taichung Science Park (T.S.P). The results indicated that the average highest TSP concentrations and dry deposition fluxes occurred in the autumn and winter seasons. The highest average metallic element concentration and dry deposition was Fe, while the lowest average metallic element concentration and dry deposition was Hg(p). The study results further indicated that the lowest metallic element concentrations and dry depositions all occurred in the summer season. The pollutant parcels originated from the northern Taiwan counties and sea surface in the autumn, winter and spring seasons. Factor 1 was responsible for the local industrial emission results and traffic road dust. The metallic elements Hg(p) yield a value greater than 0.7 in Factor 2 which revealed that ambient air particulate pollutants were generated from Taichung Thermal Power Plant (T.T.P.P.) emissions and were transported from the coastal area of mainland China cities. The mean seasonal concentration differences existed for ambient air particulates, and there were no mean seasonal concentrations differences for all metallic elements. In addition, there were no significant mean concentrations differences for all metallic elements and meteorological factors such as temperature, humidity and wind speed. Therefore, the ambient air metallic element emissions were stable and considered primary emissions sources. The health risk value for metallic element Cr was higher than that for the acceptable health risk value suggested by the EPA. Metallic element Cr revealed that it was no mean seasonal concentrations differences. Thus, metallic element Cr was considered came from local emission source at this T.S.P. sampling site. [ABSTRACT FROM AUTHOR]

The main goal of this study is to compare concentrations of atmospheric Hg(p) for various particles sizes Total Suspended Particulates (TSP), PM18, PM10, PM2.5, PM1, PM<1 before (2018–2019) and during (2019–2020 and 2020–2021) COVID-19 occurred periods in central Taiwan. In addition, test the statistical differences concentrations of Hg(p) for various particles sizes before and during COVID-19 occurred periods in central Taiwan. Finally, calculate the Hg(p) health risk assessment before and during COVID-19 occurred period in central Taiwan. The result indicated that the mean Hg(p) concentrations in TSP and PM2.5 were higher during (2020–2021) the COVID-19 occurred period than that of the mean Hg(p) concentrations in TSP and PM2.5 before the COVID-19 occurred period. In addition, the Hg(p)concentrations PM18, PM10, PM2.5, PM1 and PM<1 were all increased during the COVID-19 occurred period. The Hg(p) concentrations in TSP were decreased during (2019–2020) the COVID-19 occurred period when compared with that of the before the COVID-19 occurred period. Moreover, significant mean Hg(p) concentrations differences were existed at PM18, PM10 and PM2.5 before and during (2020–2021) COVID-19 occurred periods. Finally, the HQ and HI values for Hg(p) were both increased during COVID-19 occurred periods when compared with before COVID-19 occurred period in this study. [ABSTRACT FROM AUTHOR]

Since there have not been any atmospheric phthalate acid ester (PAE) concentration-related studies in central Taiwan during the past few years, our first atmospheric PAE study was focused on the measurement of ambient air particle-bound PAE concentrations in central Taiwan (Fang et al., 2019). However, atmospheric PAEs in the gas phase have not yet been detected. Therefore, this study was aimed toward estimating atmospheric PAE concentrations in the gas phase from known PAE concentrations in the particle-phase. Then, the total PAE concentration in the atmosphere (estimated gas-phase concentrations and measured particle-phase concentrations) could be obtained. In this study, atmospheric PAE concentrations in the gas phase are estimated from known PAE concentrations in the particle phase, and ambient air total PAE (gas phase + particle-phase) concentrations at a mixed sampling site are estimated. Mean gas-phase and particle-phase PAE concentrations are estimated and calculated as percentages of the total estimated PAE concentrations at a mixed sampling site. The particle-bound PAE concentrations were measured using a PS-1 sampler from July to December of 2018; they were also analyzed using pyrolysis-gas chromatography/mass spectrometry. The solvent extraction method was used to determine the concentrations of the PAE species. In this study, total ambient air PAE concentrations using the known PAE concentrations in the particle phase were successfully estimated. The results indicated that the average measured P-DBP, P-DEHP, and P-DnOP concentrations were 33.94, 109.70, and 12.88 ng/m3, respectively. In addition, the average estimated gas-phase DBP, DEHP, and DnOP concentrations were 776.43, 26.11, and 2.95 ng/m3, respectively. Therefore, the average total estimated concentrations for total estimated DBP, DEHP, and DnOP concentrations were found to be 810.37, 135.81, and 15.83 ng/m3, respectively, at a mixed sampling site from July to December of 2018. In addition, the DEHP concentration was the highest when measured in the particle phase, and the DBP concentration was the highest when estimated in the gas phase; the average DEHP and DBP concentrations were highest in the autumn. DnOP had the lowest measured and estimated concentrations in the gas phase in all seasons. DnOP also had the lowest average concentration in the summer. Finally, the average particulate PAE species (DBP, DEHP, and DnOP) concentrations were highest in Taichung, Taiwan (mixed site) in the period from 2000 to 2018. [ABSTRACT FROM AUTHOR]

Taichung Science Park in central Taiwan releases ambient air pollutants to the atmosphere. This issue has attracted much attention over the past few years. This study concerns seasonal concentrations of atmospheric particles and metallic elements and particle size distributions. A M.O.U.D.I sampler is used at a Taichung Science Park sampling site to obtain relevant data. Fe, followed by Al, had the highest average metallic element concentrations in particles of various sizes (PM18, PM10, PM2.5, PM1 and PM<1(0.3)); Cd had the lowest. The average concentrations of metallic elements in particles of various sizes were lowest in the summer. Fe, Al and Cr had the three highest concentrations among all metallic elements for all particles sizes in all seasons. Ambient air particulate pollutants (crustal and anthropogenic metallic elements) were released from a single emission source at Taichung Science Park site. [ABSTRACT FROM AUTHOR]

In this study, the concentrations and dry deposition of ambient air particulates are measured using a PS-1 sampler and a dry deposition plate at a suburban sampling site in central Taiwan from January 2019 to August 2019. The concentrations of metallic elements that are attached to the particulates and dry deposits are analyzed using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The source analysis model was used to identify possible emission sources of the pollutants and the transmission distributions of ambient air metallic elements. During the sampling period, the TSP concentration at the Peiying suburban sampling site was highest on January 24th (in winter) and lowest on April 29th (in spring). Dry deposition was greatest on January 9th (in winter) and least on July 29th (in summer). In addition, the correlation coefficient between temperature and ambient air particulate concentration revealed a moderate to strong negative relationship (r2 = 0.60) the ambient air particulate concentrations declined throughout the study period. Moreover, high concentrations of crustal metallic elements Al, Ca were found in this study due to the particulates suspensions from the roads in the suburban area. The Taiwan II express highway runs about 500 m to the northeast of the sampling site, explaining why high concentrations of Cu were measured in this study. The concentrations of metallic elements Ca, Cd, Ni, Pb, and Zn were highest in winter and spring while those of metallic elements Al, Cu, Cr, and Mn were highest in summer. The mean metallic elemental concentrations followed the order: Ca > Al > Zn > Cu > Mn > Ni > Pb > Cr > Cd. The dry depositions of metallic elements Ca, Pb, Zn, Ni and Cd were greatest in winter and spring and those of metallic elements Al, Cu, Cr and Mn were highest in summer. The average dry depositions of the studied metallic elements followed the order: Ca > Al > Zn > Cu > Mn > Ni > Pb > Cr > Cd. The main pollution parcel was from the north side of Taiwan, pollution parcel that associated with the northeast monsoon, resulted in ambient air pollutants emitted on Taiwan island, influencing its air quality. [ABSTRACT FROM AUTHOR]

Ambient air particulates (PM1, PM2,5, PM10, PM18, and total suspended particulates (TSP)), trace metals (Al, As, Cr, Cu, Cd, Zn, Ni, Pb, Mn, and Hg(p)) their concentrations, their dry deposition, and their sources from Dec. 2017 to May 2018 at Luliao Taichung City Junior High School (24°14′37.9″N 120°34′00.3″E) were studied. The site is a mixed site that is surrounded by traffic, and urban and commercial activities. The sources of ambient air particulates were identified by back-trajectories analysis. The trace metal concentrations in PM1, PM2.5, and PM10 were compared with those in other countries in the years 2003–2018. The level of contamination by these trace metals at this mixed site was evaluated using a contamination factor (CF) and degree of contamination (CD). The results indicated that the average concentrations of all particles were highest in January (winter season) and the average concentrations of TSP, PM18, PM10, PM2.5, and PM1 followed the order Jan. 2018 > Dec. 2017 > Apr. 2018 > Mar. 2018. The concentration of trace metals followed the order Al > Cu > Fe > Cr > Mn > Ni > As > Pb > Zn > Cd > Hg(p) in both TSP and dry deposits. Al had the highest mean concentration in PM18, PM10, PM2.5, and PM1 while Hg(p) had the lowest concentration in PM18, PM10, PM2.5, and PM1. Interestingly, elements As and Cr had higher mean concentrations in PM1 at the studied site than in the other countries of interest during the years from 2003 to 2018. CF and CD values for all trace metals revealed low degree of contamination at this mixed sampling site. The CD values for all trace metals in particle of sizes 1 to 18 μm all exceeded those calculated for TSP and dry deposits. The CD values increased with particle size from 1 μm to 18 μm. [ABSTRACT FROM AUTHOR]

The main goal of this study is to measure the ambient air of total suspended particulates at a mixed (traffic, residential and commercial) sampling site. And the concentrations of phthalate acid ester (PAE) which attached on total suspended particles were also analyzed. In addition, the possible sources of PAEs were also analyzed by the method of back trajectories. Finally, appropriate statistical methods were also used to test monthly and seasonal mean pollutants' (particulates, PAEs) concentration differences at this sampling site. The results indicated that the monthly concentration variation trends were similar for DEHP and total PAEs with the results as followed: November > October > July > December > September. In addition, back trajectories results also indicated that the main pollutant parcels were came from the east side of Taiwan in July. And the pollutant parcels were came from the north side of Taiwan during the month of September, October, November and December in this study. Moreover, the results also showed that the DEHP, DNOP, total PAEs' concentrations with TSP and meteorological conditions were not significantly different. But the relationship among DEHP, DNOP and total PAEs was significantly different; particularly, the relationship between DEHP and total PAEs was highly correlated in this study (R2 = 0.994). Finally, the statistical analysis of total PAEs T test statistic for mean monthly concentrations results suggested that the sample population means were not differed significantly. In other words, there were not any mean monthly concentration differences for PAEs at this sampling site. The only exception was occurred in the month of September versus November. The results showed that there is a statistically significant PAEs' concentration difference between the input groups (September vs. November). [ABSTRACT FROM AUTHOR]

Phthalate esters (PAEs) are ubiquitous contaminants from plasticizers of polyvinyl chloride and other polymers. The investigation of the PAEs in the environment, especially ambient air particulates, is very important. In this study, the determination of PAEs in total suspended particulates (TSP) by using gas chromatography/mass spectrometry (GC/MS) was evaluated. The results indicated that the concentrations of TSP at Luliao sampling site ranged from 40.23 to 94.9 μg m−3. In addition, Di(2-ethylhexyl) phthalate was the most abundant PAEs accounting for 89.7–98.9% of TSP. Total PAEs concentrations in central Taiwan ranged from 20.89 to 86.50 ng m−3. Moreover, the GC/MS method enabling simple, rapid, sensitive and reliable results was adopted in this study. The method is recommended for the analysis of PAEs in TSP samples from the ambient air. [ABSTRACT FROM AUTHOR]

This research was focused on the measurements of ambient air pollutants species (Cl−, NO3−, and SO42−) concentrations of wet and dry depositions by using PS-1 (TSP), dry depositions plate and wet depositions tub at mixed (traffic, commercial, and residential) sampling sites. Lu-Liao, characterized by traffic, commercial and residential sites, was selected as the dry deposition measurement site. Hungkuang University, characterized by a traffic site, was selected as the wet deposition collection site. At the Luliao site, the results indicated that the average ionic species (Cl−, NO3−, and SO42−) concentrations were 12.86, 25.58, and 18.37 μg/m3, respectively, in winter and 2.94, 11.37, and 14.09 μg/m3, respectively in spring. The average ionic species (Cl−, NO3−, and SO42−) dry depositions were 284.43, 1808.50, and 412.93 μg/m2 min, respectively, in winter and 147.66, 109.59, and 415.44 μg/m2 min, respectively, in spring. As for the monthly Cl−, NO3−, and SO42− volume weighted mean (VWM) concentrations at the Hungkuang site, the results for January were 5.64, 4.41, and 10.13 mg/L, for May were 0.45, 1.98, and 2.09 mg/L, for June were 0.76, 1.39, and 2.46 mg/L, and for July were 1.83, 2.97, and 5.84 mg/L. The monthly Cl−, NO3−, and SO42− Fw (Fluxwet deposition) at the same site were 355.41, 277.63, and 638.15 mg/m2 month, respectively, for January; 17.01, 99.03, and 362.05 mg/m2 month, respectively, for May; 99.03, 181.18, and 319.45 mg/m2 month, respectively, for June; and 362.05, 587.86, and 1156.49 mg/m2 month, respectively, for July. SO42− had the highest VWM and Fw values when compared with the other ionic species, Cl− and NO3−. The highest VWM values for all ionic species (Cl−, NO3−, and SO42−) all occurred in winter. [ABSTRACT FROM AUTHOR]

This study consisted of the collection and comparison of ambient air total suspended particulates (TSP), PM10, PM2.5 concentrations and dry depositions for semi-open/outdoor environments at a concrete processing factory in ChangHua Coastal Park during the year of 2017 (half-year observation). This study aimed to find the appropriate dry deposition models in the prediction of the semi-open/outdoor dry depositions for this factory. The results indicated that the average TSP, PM10, PM2.5 concentrations in the semi-open environment were all higher than those of the outdoor environment at this concrete processing factory, and the average dry depositions at the outdoor environment were all higher than those from the semi-open environment. A possible reason for this is the lack of any ventilation instrument during the processing period at the semi-open environment. In addition, the factory's storage area opened directly to the outdoor environment. Ambient air particles were easily suspended in the atmosphere by the high frequency of passing trucks. Thus, high ambient air dry depositions particulates were measured at the outdoor environment. 20 and 23 μm particle sizes were selected as the calculated dry depositions velocities to obtain the calculated dry depositions fluxes for both the Baklanov and Wood models in this study. The above results showed that they exhibited better dry depositions prediction results for estimating outdoor and semi-open environments at this industrial concrete processing factory. Moreover, when comparing the above two models of dry depositions prediction performance, the Wood model exhibited better than the Baklanov model. Finally, this study also indicated that the ambient air particles moved from southeast to northwest Taiwan from July to December. In addition, PM2.5 and PM10 particles concentrations gradually increased from summer through autumn and winter season. [ABSTRACT FROM AUTHOR]

The concentrations of ambient total suspended particulates (TSP) and PM2.5, and the dry depositions at a sample site at Luliao Junior High School (Luliao) in central Taiwan were measured during smog and non-smog days between December 2017 and July 2018. The results are compared to those obtained during non-smog periods in the years 2015–2017. The mean TSP and PM2.5 concentrations and dry deposition flux were 72.41 ± 26.40, 41.88 ± 23.51 μg/m3, and 797.57 ± 731.46 μg/m2 min, respectively, on the smog days. The mean TSP and PM2.5 concentrations and dry deposition flux on the non-smog days were 56.39 ± 18.08, 34.81 ± 12.59 μg/m3 and 468.93 ± 600.57 μg/m2 min, respectively. The mean TSP concentration in the smog period was 28% greater than that in the non-smog period, and the mean PM2.5 concentration was 20% higher. The mean dry deposition flux in the smog period was 70% higher than that in the non-smog period at Luliao. The PM2.5 concentrations exceeded the standards set by the Taiwan EPA (35 μg/m3 daily, and 15 μg/m3 annually). Therefore, the TSP and PM2.5 concentrations and dry deposition must be reduced in central Taiwan on smog days. In addition, atmospheric TSP and PM2.5 concentrations at various sampling sites were compared, and those herein were not higher than those measured in other countries. Finally, apart from the local traffic emissions, during smog periods, the other pollution source originated from the transportation process of traffic pollutants emitted in the northwest side of Taiwan. [ABSTRACT FROM AUTHOR]

The plum rain season in Taiwan is in May and June. The severest plum rain season over the last 21 years was in 2017. This study involves the collection of mercury wet depositions in the plum rain season of May-June in 2017. A DMA-80 (Direct Mercury Analyzer) was used to analyze the precipitated mercury concentrations and calculate the wet depositions of mercury in the plum rain season. The results indicate that the highest wet depositions of mercury in the aqueous phase were on 6/16, reaching 209.04 μg/m2 * day, while the lowest were on 5/15, at 0.18 μg/m2 * day. The mercury wet depositions in the particulate phase were highest on 6/17, when it exceeded 100 μg/kg, and lowest on particulate phase were occurred in 6/11, when it was 3.64 μg/m2 * day. The relationship between the wet depositions of mercury in the aqueous phase and rainfall was insignificant, while that between the wet depositions of mercury in the particulate phase and rainfall was significant. The wet depositions of mercury in this study were second highest (30.73 μg/m2 day) when compared with those in studies in the years 2007-2017. Although the rainfall in this study was only 564 mm H2O, high mercury concentrations obtained from the plum rain season result in the high wet depositions of mercury in Taichung, Taiwan. [ABSTRACT FROM AUTHOR]

PM has become an important environmental issue in Taiwan during the past few years. Moreover, electricity increased significantly during the summertime and TTPP generated by coal burning base is the main electricity provider in central Taiwan. Therefore, summer season has become the main research target in this study. The ambient air concentrations of particulate matter PM and PM collected by using VAPS at a mixed characteristic sampling site were studied in central Taiwan. The results indicated that the average daytime PM and PM particulate concentrations were occurred in May and they were 44.75 and 57.77 µg/m in this study. The results also indicated that the average nighttime PM and PM particulate concentrations were occurred in June and they were 38.19 and 45.79 µg/m in this study. The average PM/PM ratios were 0.7 for daytime, nighttime and 24-h sampling periods in the summer for this study. This value was ranked as the lowest ratios when compared to the other seasons in previous study. Noteworthy, the results further indicated that the metallic element Pb has the mean highest concentrations for 24-h, daytime and nighttime sampling periods when compared to those of the other metallic elements (Ni, Cu, Zn and Cd). The average mean highest metallic Pb concentrations in PM10 were 110.7, 203.0 and 207.2 ng/m for 24-h, daytime and nighttime sampling periods in this study. And there were 59.53, 105.2 and 106.6 ng/m for Pb in PM2.5 for 24-h, daytime and nighttime sampling periods, respectively. Moreover, the results further indicated that mean metallic element Pb concentrations on PM and PM were all higher than those of the other elements for 24 h, day and nighttime. [ABSTRACT FROM AUTHOR]

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 (~60 %) 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. [ABSTRACT FROM AUTHOR]

This investigation measures the concentrations of arsenic (As), (As), (As) in total suspended particles (TSP) and dry deposits at five characteristic sampling sites in central Taiwan during the years 2009-2010, and identifies their seasonal variations. The investigation was performed in region in which a science park, transportation, waste incineration facility, fossil fuel combusting steel factory, electronics factory, plastic factory, chemical factory and Taichung Thermal Power Plant (TTPP) are located. The Bei-shi sampling station and He-mei town sampling station were located in, an area of heavy transportation. The Quan-xing sampling station was close to an electronics factory and a fossil fuel combusting steel factory. The As for Chang-Hua sampling station was located at the chemical factory. Finally, the Gao-Mei wetland sampling station was close to a waste incineration; they were characterized as a waste incineration plant and TTPP. The highest average concentrations of arsenic in TSP were found at Quan-xing (industrial) and the lowest were found at He-mei (residential). The average amounts of dry deposited arsenic (As), (As) and (As) were highest at the Quan-xing (industrial) site and lowest at the Gao-mei (wetland) site. The average seasonal concentrations of (As), (As) and (As) in TSP and the average dry deposited amounts were highest in the autumn and lowest in the summer at five sampling sites. [ABSTRACT FROM AUTHOR]

This investigation studied the concentrations of ambient air total gaseous mercury (TGM) during the rainy periods at the Hung-Kuang traffic sampling site in central Taiwan from May 26 to June 16, 2014. The results were compared with those of a previous study for ambient air TGM during non-rainy daytime and nighttime periods at the Hung-Kuang traffic sampling site, which was conducted during March 21 to July 20, 2012. The observed mean concentration of ambient air TGM was 1.16 ng/m3during the rainy periods at the Hung-Kuang traffic sampling site. The mean ambient air TGM concentrations were higher in the non-rainy sampling period in daytime than in the rainy sampling period from this study. The mean ratio of non-rainy sampling period in daytime to that of rainy sampling period for ambient air TGM were 3.15. Furthermore, the mean ambient air TGM concentrations were higher in the non-rainy sampling period in nighttime in than in the rainy sampling period for this study. The mean rations for non-rainy sampling period in nighttime to that of the rainy sampling period for ambient air TGM were 2.70. The results obtained in this study also revealed that the ambient air TGM concentrations during the rainy period had the lowest concentrations when compared with the other sampling sites in other world regions. [ABSTRACT FROM AUTHOR]

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, andGynura 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 andG. 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, andGynura) in central Taiwan. The results further revealed no significant differences in mean values. [ABSTRACT FROM AUTHOR]

This study characterized the dry deposition flux and dry deposition velocity (Vd) of metallic elements attached on particulate matter. Specifically, large particles (>10 μm), coarse particles (10 μm∼2.5 μm), and fine particles (<2.5 μm) were studied at the Gong Ming Junior High School (Taichung Airport) and Taichung Harbor sampling sites in central Taiwan. Ambient air samples were collected to determine total suspended particulate matter (TSP), dry deposition plate (DDP), Vd, coarse particulate matter (PM2.5–10) and fine particulate matter (PM2.5), and metallic elements concentrations at the Airport and Taichung Harbor sites between June 17, 2013, and November 14, 2013. The results revealed that the average TSP, DDP, Vd, PM2.5–10, and PM2.5particulate at the Airport were 54.55 (μg/m3), 902.25 (μg/m2-min), 17.11 (m/sec), 0.003 (μg/m3), and 0.010 (μg/m3), respectively; while these values at Taichung Harbor were 63.66 (μg/m3), 539.69 (μg/m2-min), 9.94 (m/sec), 0.003 (μg/m3), and 0.014 (μg/m3), respectively. In addition, the results showed that the average Cu and Pb concentrations were higher than Cr, Ni, and Cd for both the airport and harbor sampling sites. Furthermore, Cr, N, Cu, Cd, and Pb had the highest average concentrations versus those reported for other study areas, with one exception: The results obtained in Kacanik, Kosovo, during 2005. The average metallic elements concentrations order was Cu > Pb > Cr > Ni > Cd. [ABSTRACT FROM AUTHOR]

Abstract: The purposes of this study were to investigate and characterize ambient air particulate concentrations and dry deposition fluxes and those metallic elements associated with them in central Taiwan during 2009–2010. At the Bei-Shi (suburban/coastal) sampling site, the average TSP concentrations, flux, and deposition velocity were 92.3 (μgm−3), 165.92 (μgm−2 min−1), and 3 (cms−1), respectively. In addition, at the Quan-Xin (industrial) sampling site, the highest average TSP concentrations of As, ambient air particulate bound mercury (Hg(p)), Mn, Fe, Zn, Cr, Cu and Pb were 3.56, 0.07, 82.21, 2769.82, 109.33, 31.93, 109.76 and 39.15ngm−3, respectively. The highest average dry deposition flux of elements As, Hg(p), Mn, Fe, Zn, Cr, Cu and Pb were 2.36, 0.15, 18.11, 303.8, 35.59, 18.66, 45.47 and 42.6 (ngm−2 min−1), respectively in Quan-Xin (industrial). The median deposition velocity (Vd) of metallic elements was present at the five characteristic sampling sites, respectively. However, the median dry deposition velocity (Vd) of Hg(p) was 2.73–4.78cms−1, higher than all other elements in the five characteristic sampling sites during 2009–2010. The median dry deposition velocity (Vd) of Fe was 0.17–0.27cms−1, lower than all other elements in the five characteristic sampling sites during 2009–2010. [Copyright &y& Elsevier]

This study aimed to measure and discuss the relationship of ambient air precipitations with respect to mercury wet depositions at suburban, agriculture and traffic three characteristic sampling sites during the year of 2019. In addition, the mercury volume weighted mean concentrations (VWM) at three characteristic sampling sites were also calculated. Finally, the ambient mercury wet depositions data obtained in this study to various world sampling sites were also compared and discussed in this study. The results indicated that the average mercury wet depositions for suburban, agriculture and traffic areas were 0.62, 0.55 and 2.32 ng/m 2  min, respectively. And the average mercury VWM values were 0.9, 0.72 and 1.85 ng/m 2  min for suburban, agriculture and traffic sites, respectively. In addition, the highest VWM and wet depositions for mercury both occurred in March at traffic and suburban areas. And the mercury wet depositions displayed a declined trend when the month was moved from March to July at both traffic and suburban sampling sites. In addition, the relationship between wet depositions and precipitations was low to moderate correlated in traffic area, while the relationship between wet depositions and precipitations was insignificant at both suburban and agriculture areas. Moreover, the average highest mercury wet deposition occurred in Nepal when compared to the other world sites. In addition, the average value of mercury wet depositions in Nepal was about 17.23 times to that of data obtained in this study during the period of 2007-2019. Finally, the average highest VWM (ng/L) occurred in the China. In addition, the average value mercury VWM in China was about 14.82 times to that of data obtained in this study during the period of 2007-2019.

The particulate size distributions of aerosol pollutants (particulates and Hg(p)) at a mixed site were measured and their seasonal variations identified. Atmospheric particulates and the Hg(p) mass median diameter (m.m.d.) were obtained. Hg(p) concentrations increased by approximately 20% during the peak demand period for all particle sizes (18, 10, 2.5, 1 and 0.3 μm). The mean percentage concentration of Hg(p) was highest in summer and followed the order summer > spring > winter > autumn for all particle sizes. Hg(p) concentration exhibited increased from 2004 to 2019.

The ambient air particulates pollutants of total suspended particulates (TSP) and PM 2.5 were collected by using PS-1 and Wilbur PM 2.5 sampler, simultaneously during the year of 2015-2017 at a photoelectric factory in Science Park of central Taiwan. And those of the ambient air atmospheric metallic elements (Cr, Mn, Ni, Cu, Zn, Pb) concentrations which attached on the TSP and PM 2.5 were analyzed by using inductively coupled plasma optical emission spectrometer. In addition, identifying anthropogenic and natural pollutants sources were conducted by using the enrichment factor (EF) and principal component analysis (PCA) methods. The results indicated that the average TSP and PM 2.5 concentrations were ranked highest in winter season, while summer season was ranked lowest during the year of 2015-2016. In addition, the average highest metallic element concentrations were occurred in winter season for both TSP and PM 2.5 during the year of 2015-2016, while the average lowest metallic elements concentrations in TSP and PM 2.5 were also occurred in winter season during the year of 2016-2017. Moreover, the EF analysis results showed that the metallic element Zn came from anthropogenic emission source. As for metallic element Mn, the results showed that metallic element Mn was mainly attributed to natural emission in this study. Finally, the PCA results showed that metallic elements Cr, Zn and Pb were the dominant emissions metallic elements in this study. As for PM 2.5 , the results showed that the metallic elements Cr, Cu and Pb were the dominant emissions metallic elements at this HPB sampling site.