Abstract
A method, using microporous membrane liquid-liquid extraction technique (MMLLE) and gas chromatography with an electron capture detector (GC-ECD) and gas chromatograph coupled to a mass spectrometer, was developed for the analysis of cyclic organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in sediment slurry. The MMLLE extraction employed isooctane as the organic liquid that was immobilised in the hollow fibre pores and in the lumen, at optimal sample pH value of 2.0 for OCPs and 7 for PCBs. The effect of triton x-100, in enhancing the dissolution of the compounds from sediment, was found to be optimal at a value of 0.15%, while the ionic strength was optimal at a value of 0.01 M. Samples from coastlines along the Indian Ocean in the southern parts of South Africa were found to be contaminated with cis and trans chlordane at concentrations of up to 0.003 mg/kg, while samples from northern parts were contaminated with 2,2’,4’,4-tetrachloro-1,1’biphenyl at concentrations of up to 0.02 mg/kg.Keywords: Organochlorine pesticides, polychlorinated biphenyls, hollow fibre liquid phase micro-extraction, high performance liquid chromatography, mass spectrometry
Highlights
Persistent organic pollutants, for example, organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), are used worldwide for many purposes, including the control of plant diseases and disease vectors (Sanchez et al, 2006)
Organochlorine pesticides tend to be persistent in the environment because the presence of chlorine in an organic molecule reduces reactivity towards oxidation, and, being of low solubility in water; they are resistant to hydrolysis (Hong et al, 1999; Tanabe et al, 1997; Safe, 1990)
Several analytical parameters had to be optimised to enhance the extractability of OCPs and PCBs from sediment
Summary
Persistent organic pollutants, for example, organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), are used worldwide for many purposes, including the control of plant diseases and disease vectors (Sanchez et al, 2006). Organochlorine pesticides tend to be persistent in the environment because the presence of chlorine in an organic molecule reduces reactivity towards oxidation, and, being of low solubility in water; they are resistant to hydrolysis (Hong et al, 1999; Tanabe et al, 1997; Safe, 1990) These persistent organic pollutants have a tendency to concentrate in fatty tissues and bio-accumulate in the food chain due to their high hydrophobicity (Chen et al, 2002). Chemical characteristics and properties which determine their persistence and toxicities in waters and soils This makes the development of sensitive and selective analytical methods crucial, for the detection of the presence of these persistent organic pollutants and their degradation products, and to study their distribution across the environmental compartments. The extraction protocol essentially consists of 1 step, i.e., extraction of the analyte from the sample phase using an organic solvent (Pedersen-Bjergaard and Rasmussen, 1999)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
