ABSTRACT
Polychlorinated biphenyls (PCBs) are remarkable pollutants due to their ubiquitous environmental distribution and chronic toxicity (1-4). Though PCBs are generally recalcitrant to chemical and biological degradation, they are photodegradable (5-7). Most PCBs have weak absorption bands that partially overlap the solar spectrum in the ultraviolet (UV) region at wavelengths above https://www.w3.org/1998/Math/MathML"> 280 n m ( 5 ) https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429080050/6559e41b-64b9-4256-96a3-5980cbb6d757/content/eq3082.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> . Photodegradation is reported as an important process of PCB decomposition in the environment (7-8). The loss of PCBs in natural water due to solar radiation has been estimated to be of the order of 10 to https://www.w3.org/1998/Math/MathML"> 1000 g / k m 2 / https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429080050/6559e41b-64b9-4256-96a3-5980cbb6d757/content/eq3083.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> year https://www.w3.org/1998/Math/MathML"> ( 9 ) https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429080050/6559e41b-64b9-4256-96a3-5980cbb6d757/content/eq3084.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> . Artificial lights with wavelengths less than https://www.w3.org/1998/Math/MathML"> 280 n m https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429080050/6559e41b-64b9-4256-96a3-5980cbb6d757/content/eq3085.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> are absorbed strongly by PCBs and are therefore useful in decontaminating PCB-containing wastewaters. However, direct application of photolysis to remediation of PCBcontaminated soil is limited due to lack of light penetration.
