title: Investigation of organochlorine pesticides from the Indus Basin, Pakistan: sources, air-soil exchange fluxes and risk assessment.
abstract: Present study aimed to evaluate the contamination status of organochlorine pesticides (OCPs) and their associated potential for air-soil exchange and health risks from ecologically important sites of the Indus Basin, Pakistan. Among different OCPs investigated, ΣDDTs and ΣHCHs were more prevalent compounds in the agricultural soils and ambient air samples of the study area. The average concentrations for DDTs were found higher at downstream agricultural sites, particularly at Head Panjnad (Soil: 320 ng/g; Air: 743 pg/m(3)) and acting as an ultimate sink of ΣOCP burden in soils. Spatial distribution patterns inferred ubiquitous distribution of ΣDDTs in soils and air of the study area. Source diagnostic ratios demonstrated that studied OCPs either are illegally being used in agricultural practices or/and they are residues of past use in the environment. Fugacity fraction model revealed wide variations (ff=0.12-0.94) with 20% of OCPs above equilibrium range and net volatilization of α-endosulfan, β-HCH and o,p'-DDD. Assessment of cancer risks for OCPs indicated a higher cancer risk (CR>1×10(-6)) for the residents of the Indus Basin. According to the available soil quality guidelines, DDTs and HCHs were above the permissible limits and pose a threat to natural habitat and biodiversity of the Indus Basin.
authors.affiliation: Environmental Biology and Ecotoxicology Laboratory, Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-I-Azam University, Islamabad 45320, Pakistan.
authors.forename: Jawairia
authors.initials: J
authors.lastname: Sultana
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China. Electronic address: shahg14@gmail.com.
authors.forename: Jabir Hussain
authors.initials: JH
authors.lastname: Syed
authors.affiliation: Environmental Biology Laboratory, Department of Plant Sciences, Faculty of Biological Sciences, Quaid-I-Azam University, Islamabad 45320, Pakistan.
authors.forename: Adeel
authors.initials: A
authors.lastname: Mahmood
authors.affiliation: Environmental Biology and Ecotoxicology Laboratory, Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-I-Azam University, Islamabad 45320, Pakistan.
authors.forename: Usman
authors.initials: U
authors.lastname: Ali
authors.affiliation: Environmental Biology and Ecotoxicology Laboratory, Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-I-Azam University, Islamabad 45320, Pakistan.
authors.forename: Muhammad Yasir Abdur
authors.initials: MYA
authors.lastname: Rehman
authors.affiliation: Environmental Biology and Ecotoxicology Laboratory, Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-I-Azam University, Islamabad 45320, Pakistan. Electronic address: r_n_malik2000@yahoo.co.uk.
authors.forename: Riffat Naseem
authors.initials: RN
authors.lastname: Malik
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Gan
authors.initials: G
authors.lastname: Zhang
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D004784:Environmental Monitoring; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D010154:Pakistan; D010575:Pesticides / Q000032:analysis*; D018570:Risk Assessment; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D012987:Soil; D012989:Soil Pollutants
keywords: Agricultural soils; Air–soil exchange; Indus Basin; Organochlorine pesticides (OCPs); Risk assessment; Source apportionment