Remediation of groundwater polluted with HCHs using solar ligh irradiation

During the 20th century, lindane (γ-hexachlorocyclohexane, HCH, C6H6Cl6 ) was a pesticide produced and marketed worldwide. The synthesis of this compound was carried out with benzene and chlorine under UV irradiation [1]. In 2008, the European Union forbade the production of lindane because it was classified as a cancerogenic compound by the International Agency for Research on Cancer. Despite this, uncontrolled industrial landfills still exist where chemical companies dumped tonnes of lindane and other isomers of HCH over the years, causing soil and groundwater pollution by leaching [2]. In Spain, two landfills in the Aragón region (northeast of Spain) are highly contaminated by lindane production wastes (Bailín and Sardas). For this reason, it is necessary to develop clean and efficient technologies that allow the removal of HCH isomers (HCHs) from water bodies.