| Title: | "Soil-air partitioning of semivolatile organic compounds in the Lesser Himalaya region: Influence of soil organic matter, atmospheric transport processes and secondary emissions" |
| Author(s): | Riaz R; Malik RN; de Wit CA; |
| Address: | "Environmental Biology and Ecotoxicology Laboratory, Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, PO 45320, Pakistan. Environmental Biology and Ecotoxicology Laboratory, Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, PO 45320, Pakistan. Electronic address: r_n_malik@qau.edu.pk. Department of Environmental Science, Stockholm University, SE-10691, Stockholm, Sweden" |
| DOI: | 10.1016/j.envpol.2021.118006 |
| ISSN/ISBN: | 1873-6424 (Electronic) 0269-7491 (Linking) |
| Abstract: | "After decades of imposed regulations about reducing the primary emissions of persistent organic pollutants (POPs), these pollutants are still present in the environment. Soils are important repositories of such persistent semivolatile organic contaminants (SVOCs), and it is assumed that SVOCs sequestered in these reservoirs are being re-mobilized due to anthropogenic influence. In this study, concentrations of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) in soil and air, their fugacities, fluxes and the soil-air partition coe ffi cient (K(SA)) were determined for three different land cover types (glacial, remote/mountainous and urban) of the Lesser Himalayan Region (LHR). The concentrations of OCPs, PCBs and PBDEs in soils and air ranged between 0.01 and 2.8, 0.81-4.8, 0.089-0.75 ng g(-1); 0.2-106, 0.027-182, and 0.011-7.26 pg m(-3), respectively. The levels of SVOCs in the soil were correlated with soil organic matter (SOM) indicating that SOM is a substrate for the organic pollutants in soils. The Clausius-Clapeyron plots between ln P and inverse of temperature (1000/T) suggested that long range atmospheric transport was the major input source of PBDEs and higher chlorinated PCBs over the LHR. The uneven and wide distribution of local sources in LHR and up-slope enrichment of SVOCs explained the spatial variability and altitudinal patterns. The soils near mountain and urban lakes act as local sinks of SVOCs such as beta-HCH, pp?S-DDT, CB-28, -118, -153, BDE-47, -99, and -154, with soil-air exchange fluxes tending more toward deposition. However, the soils near glacial lakes acted as local sources of more volatile congeners of alpha-HCH, gamma-HCH, op'-DDT, pp'-DDE and lower to medium chlorinated PCBs such as CB-18, -28, -53, -42 and BDE-47, -99, with soil-air exchange tending more toward volatilization flux" |
| Keywords: | "*Air Pollutants/analysis Environmental Monitoring *Hydrocarbons, Chlorinated/analysis *Pesticides/analysis *Polychlorinated Biphenyls/analysis Soil *Soil Pollutants/analysis Long range atmospheric transport Re-volatilization Soil organic matter Soil-air e;" |
| Notes: | "MedlineRiaz, Rahat Malik, Riffat Naseem de Wit, Cynthia A eng England 2021/09/21 Environ Pollut. 2021 Dec 15; 291:118006. doi: 10.1016/j.envpol.2021.118006. Epub 2021 Aug 19" |
