Case Study PCBs

Cooper DA, Peterson K. Simpson D. 1996. Hydrocarbon PAH and PCB emissions from ferries A case study in the Skagerak Kattegatt Oresund region. Atmos Environ 30(14) 2463-2473. 

Laane, R.W.P.M., Sonneveldt, H.L.A., Van der Weijden, A.J. and Groenveld, G. (1999). Trends in the spatial and temporal distribution of metals (Cd, Cu, Zn an Pb) and organic compounds (PCBs and PAHs) in Dutch coastal zone sediments from 1981-1996 a model case study for Cd and PCBs. Journal of Sea Research, 41, 1-17. 

Richardson WL, Smith VE, Wethington R (1983) In Mackay D, Peterson S, Eisenreich SJ, Simmons MS (eds) Dynamic mass balance of PCB and suspended solids in Saginaw Bay - A case study in physical behavior of PCBs in the Great Lakes. 

Case study of multi-media fate of POPs (PAHs vs. PCBs)... 

Tessmer, M. (2005) PCBs in the last frontier A case study on the scientific method. Journal of College Science Teaching 54(10), 34-36. 

A concrete example relates to the environmental levels of e.g. PCB, dioxin, pesticides or mercury, or air contamination including small particles. These have been associated with impaired perception, intelligence and mobility in children, entailing impaired earning ability and enhanced social inequity. Several case studies have indicated a loss of around 5 IQ points in a population due to hazardous chemicals, which might mean about a 10% loss of income or about the same loss of worker productivity (Trasande et al. 2005, IFCS 2003a). 

Rudel, R.A., Seryak, L.M., et al (2008) PCB-containing wood fioor finish is a likely source of elevated PCBs in residents blood, household air and dust a case study of exposure. Environmental Health, 7. 

Photochemical reactions of PCDEs have been studied in different solvents, but no difference in the amount of PCDFs has been observed [72,73], In the case of PCBs, the rate of dechlorination is faster in polar solvents than in hydrocarbon solvents [3]. Dehalogenated PCDEs have dominated in photolysis in -hexane [72], but photolysis of PCDEs in acetone solution inhibits dechlorination and favors photocyclization [73]. Therefore, it has been suggested that reactions in the environment in conditions near to acetone solution could have significance in the formation of PCDFs from PCDEs [73]. Photolysis in acetone solution can be used to synthesize PCDF congeners [74]. Carbonium ion is a possible intermediate in ring closure of PCDEs to PCDFs [75]. PCDFs can be synthesized from PCDEs... 

Polyhalogenated aromatic hydrocarbons TCDD (2,3,7,8-tetrachlorodibenzo p dioxin), PBB (polybromated biphenyls), PCDF (polychlorinated dibenzofuran), PCBs (polychlorinated biphenyls), hexachloro benzene, 2,4- dichlorophenol Appears to correlate with carcinogenic effect. Case studies for PCB and organochlorine pesticides resulted infections associated with immunosuppression... 

Vater ST, Velazquez SF, Cogliano VJ. 1995. A case study of cancer data set combinations for PCBs. 

Eriksson, L., Andersson, P.L., Johansson, E. and Tysklind, M. (2002) Multivariate biological profiling and principal regions of compormds the PCB case study. /. Chemom., 16, 497-509. 

Uses of PCBs, health effects, TSCA regulation, disposal methods, control strategy, transformer registration requirements, control thresholds, and case studies. 

TCDD (57). Any photochemical or chemical treatment process which would substantially enrich a PCB deposit in these structures, regardless of its destruction efficiency, would be undesirable. PBB photoproduct mixtures are of increased toxicity due to this sort of isomer redistribution (60). In the case of PCB the preferential photochemical reaction of o ibO halogens may lead to intermediate mixtures of enhanced toxicity and this aspect of PCB reactivity warrants further study. As noted above the product distribution ratio changes markedly on going from direct to sensitized photolysis (IJ,) and thus it may be possible to control the nature of the photolysate residue. 

Tanabe S, Tatsukawa R, Phillips DJH (1987) Mussels as bioindicators of PCB pollution a case study on uptake and release of PCB isomers and congeners in green-lipped mussels (Perna viridis) in Hong Kong waters. Environ Pollut 47 41-62... 

International Technology Corporation, 1986, Case Studies of PCB Transformer Fires (Draft), prepared for the Electric Power Research Institute, Palo Alto, California, Contract RP1263-20. 

Case study 1 Estimate the settling flux of particle bound polychlorinated biphenyls (PCBs) in the North Atlantic, knowing their concentrations in the particle phase. Assume general chlorophyll a concentrations and fluxes of organic carbon. This case study estimates the flux and MTC using Equations 17.4 and 17.5. 

Case study 4 Compare the fluxes of PCBs 52 and 153 in the Norwegian Sea due to settling of particles and deep water formation, from known dissolved and particulate concentrations, and rates of deep water formation and settling (data from Lohmann et al, 2006a). This case study uses the chemical flux (Equation 17.10) and MTC (Equation 17.12) of the physical pump deep water formation. 

We can estimate Cchem,p for the PCBs by first calculating the concentration of OC in the water and then applying a bioconcentration factor, BCF, to use Equation 17.6 (see case study 3 for example). Alternatively, as detailed in case study 1, we use aqueous concentrations of particulate PCBs and then derive the MTC of the OC settling flux, op, using Equation 17.5. 

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