Polychlorinated dibenzo dioxin. atmospheric

Brubaker WW, RA Hites (1997) Polychlorinated dibenzo-/)-dioxins and dibenzofurans gas-phase hydroxyl radical reactions and related atmospheric removal. Environ Sci Technol 31 1805-1810. 

At the same time the issues related to the unintentionally produced dioxins and furans, i.e., polychlorinated dibenzo- -dioxins (PCDDs) and PCDFs, attracted public attention in 1983 when investigations revealed that dioxins were detected in the fly ashes from municipal waste incinerators. Therefore, measures to monitor dioxins in the bottom sediment and aquatic animals and plants in the rivers, lakes, marshes and seawaters as well as the atmosphere were initiated in 1986. Investigations were implemented on the actual status of waste incinerators in 1984 and pulp and paper factories in 1990. On the basis of these findings, guidelines and administrative guidance on controlling emissions of dioxin-related chemicals were derived and established. 

Published data on PCDD/Fs in the environment of the PRD is still limited. A short-term sampling scheme was conducted to determine the levels of particle-bound polychlorinated dibenzo- -dioxins and dibenzofurans (PCDD/Fs) in Guangzhou atmosphere and evaluate the impact of PCDD/ Fs to inhabitants. Samples were collected from four different districts of Guangzhou. The results showed that industrial activities had more influences on levels of PCDD/Fs in the sampled districts. The mean PCDD/Fs concentrations (i.e., mean I-TEQ values) of Huadu district, Liwan district, Tianhe district and Huangpu district were 3815-26,530 fg m-3 (104.6-769.3 fgl-TEQ m-3). Emission source analysis indicated that small diffuse sources were relatively important (Yu et al., 2006). 

Brzuzy, L. P., Hites, R. A. Estimating the atmospheric deposition of polychlorinated dibenzo-/)-dioxins from soils. Environmental Science and Technology, 29(8) 2092-2098 (1995). 

Venier, M., Ferrario, J., et al. (2009) Polychlorinated dibenzo-/)-dioxins and dibenzofurans in the atmosphere around the Great Lakes. Environmental Science and Technology, 43(4) 1036-1041. 

For polychlorinated biphenyls (PCBs), rate constants were highly dependent on the number of chlorine atoms, and calculated atmospheric lifetimes varied from 2 d for 3-chlorobiphenyl to 34 d for 236-25 pentachlorobiphenyl (Anderson and Hites 1996). It was estimated that loss by hydroxy-lation in the atmosphere was a primary process for the removal of PCBs from the environment. It was later shown that the products were chlorinated benzoic acids produced by initial reaction with a hydroxyl radical at the 1-position followed by transannular dioxygenation at the 2- and 5-positions followed by ring fission (Brubaker and Hites 1998). Reactions of hydroxyl radicals with polychlorinated dibenzo[l,4]dioxins and dibenzofurans also play an important role for their removal from the atmosphere (Brubaker and Hites 1997). The gas phase and the particulate phase are in equilibrium, and the results show that gas-phase reactions with hydroxyl radicals are important for the... 

The environmental burden of waterways with polychlorinated dibenzo-p-dioxins (PCDD) has been at the forefront of public and regulatory concern, because of the toxicity associated with particularly the 2,3,7,8-(laterally) substituted congeners, which have a tendency to bioaccumulate throughout the trophic food chain. Contamination of aquatic sediments by dioxins includes both non-point (e.g., atmospheric deposition) and point sources (e.g., industrial effluents, combined sewage overflows), and is generally characterized by a dominance of hepta- and octa-CDD, with minor contributions of hexa- to tetra-CDD [429]. Elevated concentrations of the 2,3,7,8-TCDD isomer tend to be associated with direct discharge from sources such as 2,4,5-trichlorophenol production [54,430]. 

Brubacker, W. W. Jr., and R. A. Hites, Polychlorinated dibenzo-p-dioxins and dibenzofurans Gas phase hydroxyl radical reactions and related atmospheric removal , Environ. Sci. Technol., 31, 1805-1810 (1997). 

Many persistent organic pollutants (POPs) are semivolatile compounds which undergo exchange between air and atmospheric particles, soils, and vegetation. Classes of POPs include polychlorinated biphenyls (PCBs), pesticides, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs, PCDFs). The distribution of these substances between the particle and gas phases in the atmosphere is a... 

Moon, H.-B., Lee, S.-J., Choi, H.-G., Ok, G., 2005. Atmospheric deposition of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in urban and suburban areas of Korea. Chemosphere 1525-1534,. ... 

Oh, J.-E., Choi, J.-S., Chang, Y.-S., 2001. Gas/particle partitioning of polychlorinated dibenzo-p-dioxins and dibenzofurans in atmosphere evaluation of predicting models. Atmos. Environ. 35, 4125 1134. 

Kaupp, H., McLachlan, M.S., 2000. Distribution of polychlorinated dibenzo-P-dioxins and dibenzofurans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs) within the full size range of atmospheric particles. Atmos. Environ. 34, 73-83. 

Yu, L., Mai, B., Meng, X., Bi, X., Sheng, G., Peng, P., 2006a. Particle-bound polychlorinated dibenzo-p-dioxins and dibenzofurans in atmosphere of Guangzhou, China. Atmos. Environ. 40, 96-108. 

Ogura, I., Masunaga, S., Nakanishi, J., 2001. Atmospheric deposition of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in the Kanto Region, Japan. Chemosphere 44, 1473-1487. 

Eitzer BD, Hites RA. 1989b. Polychlorinated dibenzo-p-dioxins and dibenzofurans in the ambient atmosphere of Bloomington, Indiana. Environ Sci Technol 23 1389-1395. 

EPA. 199 Id. Atmospheric transport and deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans. Washington, DC U.S. Environmental Protection Agency. EPA600/3-91/002 Order No. PB91-144667. 

Kuwata K, Yamashita Y, Nakashima S, et al. 1993. Practical method for monitoring polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in the atmosphere. J Chromatogr 643(1-2) 25-33. 

Tysklind M, Faengmark I, Marklund S, et al. 1993. Atmospheric transport and transformation of polychlorinated dibenzo-p-dioxins and dibenzofurans. Environ Sci Technol 27(10) 2190-7. 

Polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) (see Figure 1) are emitted into the atmosphere from the combustion of chlorine-containing materials.1-13 Additionally, PCBs, which were used as lubricants and dielectric fluids,13 are volatilized into the atmosphere from soils and bodies of water (for example, from the Great Lakes) after their disposal or inadvertent release into, and cycling through, the environment.114-18 Atmospheric concentrations of PCBs, PCDDs and PCDFs have been measured at numerous locations,2,15,1619-62 and these organochlorine... 

Previous contributions to this series1-3 have highlighted the concern over emissions of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) to atmosphere from waste incineration processes. Regulatory control of these emissions has typically been addressed in two ways ... 

Kurokawa Y, Matsueda T, Nakamura M, et al. 1996. Characterization of non-ortho coplanar PCBs, polychlorinated dibenzo-p-dioxins and dibenzofurans in the atmosphere. Chemosphere 32(3) 491-500. 

Atmospheric Transport and Deposition of Polychlorinated Dibenzo-p-Dioxins and Dibenzofurans... 

Wurl O, Potter JR, Obbard JP, Durville C (2006) Persistent organic pollutants in the equatorial atmosphere over the open Indian Ocean. Environ Sci Technol 40 1454-1461 Yang JS, Lee DW, Lim H (2003) Microwave-assisted extraction (MAE) of polychlorinated biphenyls and polychlorinated dibenzo-p-dioxins from fly ash and sea sediments effect of water and removal of interferences. J Liq Chromatogr Rel Technol 26 803-818... 

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