Transformation of DDT and Its Metabolites by Various Abiotic Methods

This work looks at several new abiotic treatment methods for transformation of DDT in an aqueous solution. Various combinations of calcium peroxide (CaO2), zero-valent iron (Fe0), iron sulfide (FeS), and hydrogen peroxide (H2O2) were utilized to promote the abiotic transformation of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) in electrolyte, hydroquinone, and nonionic surfactant (Triton X-114) systems. Treatment with CaO2 resulted in 86% DDT mass reduction within 10 days of treatment with only traces of 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD) , 1,1-dichloro-2,2-bis(pchlorophenyl)ethylene (DDE), and 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (DDMU) being generated. Treatments with 1:1 mixtures of Fe0:CaO2 and FeS:CaO2 resulted in 86 and 85% DDT mass transformation, respectively, within 8 days. A mixture of 0.75 g Fe0:0.1 g CaO2 showed similar results with 79% DDT mass transformed within 8 days. A mixture of 0.750.1 g of Fe0:FeS resulted in 85 and 97% transformation in the total mass of DDT in an electrolyte solution and a hydroquinone solution, respectively. The treatment of DDT in aqueous solution by CaO2, in the presence of Triton X-114, resulted in the transformation of 97% of the total mass of DDT within 30 days, albeit, large amounts of DDE (402 mM) were generated.