Cluster Analysis for Polychlorinated Dibenzo- p -Dioxins and Dibenzofurans Concentrations in Southern Taiwan

Self Cite

The characteristics of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and the variation of the gas-particle partitioning of PCDD/Fs near two municipal solid waste incinerators (MSWIs) located in southern Taiwan were investigated. In order to better understand the mechanism of dry deposition, the atmospheric dry deposition flux and velocity of PCDD/Fs were calculated. It was found that the mean atmospheric PCDD/F concentrations (0.0386-0.106 pg I-TEQ/Nm 3 ) were comparable to those detected in the vicinity of MSWIs in Taiwan, but significantly lower than those in a highly industrialized urban area (0.15 pg I-TEQ/Nm 3 ) located in southern Taiwan. The relatively higher atmospheric PCDD/F concentrations was found in winter than in summer, probably because of several loss process including photolysis, chemical reactivity, wet and dry deposition, and scavenging by vegetation. The calculated total dry deposition flux of PCDD/Fs ranged from 0.0274-0.718 ng I-TEQ/m 2 -month, and the atmospheric deposition flux in winter tended to be higher than those in summer. The results also indicated that dry deposition velocities of atmospheric particles for each month ranged from 0.52-0.91 cm/s (mean = 0.63 cm/s) and 0.48-0.73 cm/s (mean = 0.55 cm/s) in sites A and B, respectively, which were similar to that for the ambient air near two MSWIs in Taiwan, but slightly higher than those in urban area of Korea. In addition, the dry deposition of PCDD/Fs was mainly contributed by particle-phase at both sampling areas during the estimated period. The above results demonstrated that the dominant mechanism of dry deposition was particle phase deposition.

Section: Concentrations Of Pcdd/fs In the Ambient Airsupporting

confidence: 92%

Characterization of Atmospheric Dry Deposition of Polychlorinated Dibenzo-p-dioxins/Dibenzofuran in a Rural Area of Taiwan

Huang

Chen

Lai

et al. 2011

Self Cite

“…The above PCDD/F concentration levels were similar to previous studies in southern Taiwan near two municipal solid waste incinerators and one coal-fired power plant (0.0319-0.0847 pg I-TEQ/Nm 3 ), but slightly higher than those in northern Taiwan near a heavy oil-fueled power plant (0.004-0.022 pg I-TEQ/Nm 3 ) (Hsieh et al, 2009;Wang et al, 2009a). Previous studies have reported that the PCDD/F concentration in winter was four to eight times higher than in summer in rural Germany due to the demand for domestic heating, while atmospheric PCDD/F concentrations also varied with the seasons, because of photolysis and its effects on chemical reactions (Hippelein et al, 1996;Lohmann and Jones, 1998).…”

Section: Pcdd/f Concentration In the Ambient Airsupporting

confidence: 86%

“…Previous studies have shown that the PCDD/F concentration from the stacks of power plants are between 0.41 and 50 pg I-TEQ/Nm 3 (Fernández-Martínez et al, 2004;Lin et al, 2007;Hsieh et al, 2009;Wang et al, 2009a). Although the PCDD/F concentrations from power plants are low, the total amount of PCDD/F emission can not be neglected.…”

Section: Introductionmentioning

confidence: 99%

Monitoring and Identification of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans in the Ambient Central Taiwan

Chien

et al. 2010

Self Cite

Polychlorinated Dibenzo-p-dioxins and Dibenzofurans (PCDD/Fs) in the ambient air of five sampling sites around central Taiwan were investigated. Principal components analysis (PCA), cluster analysis (CA) and the chemical mass balance (CMB) model were adopted to assess possible PCDD/F sources and their effects on the air quality levels. Field experimental results showed that the mean PCDD/F concentrations in the ambient air were 0.0526, 0.0591, 0.0339 and 0.0727 pg I-TEQ/Nm 3 in winter, spring, summer and autumn, respectively. Analysis of atmospheric isopleths for five sampling sites displayed that high PCDD/F concentrations were mostly close to electric arc furnace plants (EAF). Through PCA and CA, the congener profiles of ambient air sampling sites were close to medical waste incinerators (MWI), secondary aluminum smelters (ALS), EAF, waste open burning (OB) and crematories (CM). By using the CMB model, the dominant sources of PCDD/Fs in ambient air were EAF, medical waste incinerator/municipal solid waste incinerators (MWI/MSWI) and unleaded gasoline fuel vehicle/diesel fuel vehicle (UGFV/DFV), which contributed 22-23%, 17-31% and 9-22%, respectively. The above results revealed that ambient air was affected by surrounding PCDD/F sources (MWI, ALS, EAF, CM and OB). However, due to high stack height and low emission concentration, the impact of coal-fired power plant on the PCDD/F levels of ambient air was insignificant.

“…For comparison, our previous study (Chang et al, 2003) also indicated that the atmospheric PCDD/F concentrations measured in the vicinity of municipal waste incinerators in northern Taiwan ranged from 56.0 to 348 fg I-TEQ/m 3 . Other relevant studies (Hsieh et al, 2009;Wu et al, 2010b) have also indicated that atmospheric PCDD/F concentrations measured in industrial parks in central and southern Taiwan range from 33.9 to 72.7 fg I-TEQ/m 3 and 19.0 to 165 fg I-TEQ/m 3 , respectively. In other Asian countries such as Korea and Japan, the atmospheric PCDD/F concentrations in urban areas have been shown to range from 28 to 120 fg I-TEQ/m 3 (Makiya, 1999;Lee et al, 2007), which are similar to another of our previous studies (Chi et al, 2008a) where we measured atmospheric PCDD/F concentrations in an urban area of Taiwan to be in the range 20 to 110 fg I-TEQ/m 3 .…”

Section: Variation In Ambient Pcdd/f Concentrations In Northern Taiwamentioning

confidence: 91%

Increase of Ambient PCDD/F Concentrations in Northern Taiwan during Asian Dust Storm and Winter Monsoon Episodes

Hsien¹,

Chou

Peng

et al. 2014

In the spring, Asian dust storms that originate in the deserts of Mongolia and China eventually reach the populated areas of East Asia. The dust storm particles usually contain diverse organic matter and nutrients that may have an adverse effect on human health. In winter, northeast monsoon episodes that originate in the mainland China not only bring cold air but also transport dust and air pollutants to Taiwan over long distances. Based on the above, the presence of persistent organic pollutants (POPs), including polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), in the suspended particles undergoing long-range transport needs to be investigated. In this study, the atmospheric concentrations of PCDD/Fs were monitored and investigated during an Asian dust storm episode and northeast monsoon episode in northern Taiwan. The sampling results indicate that the atmospheric PCDD/Fs observed at two remote sampling sites ranged from 7.46 ± 0.7 to 37. rd December 2008, respectively. Specifically, higher levels of PCDFs (by 70%-76%) were measured in northern Taiwan during these long-range transport periods. As no specific dioxin emission sources exist within 20 km of our sampling sites, the increase in PCDD/F concentrations observed at these two remote sampling sites is likely to be related to the Asian dust storm and northeast monsoon episodes and the pollutants would seem to have come from mainland China.