ENVIRONMENTAL TRANSFORMATION MECHANISMS OF THIODIGLYCOL

The fate of thiodiglycol (TDG) in environmental samples was studied th rough analysis of batch solid-solution suspensions. We monitored aqueo us-phase TDG concentrations and thiodiglycolic acid (TGDA) concentrati ons by high-performance liquid chromatography with ultraviolet detecti on. We investigated TDG and TDGA sorption to six soils. Thiodiglycol s orption was insignificant, with a maximum sorption capacity of less th an 10 mg/kg. Sorption of TDGA varied, with maximum sorption capacities ranging from 19.9 to 427.4 mg/kg. Photolysis, hydrolysis, and the pre sence of iron oxide and aluminum oxide had little effect on the fate o f TDG and TDGA. However, manganese oxide sorbed TDG and was pH depende nt. Biological transformation of TDG to TDGA, with the formation of [( 2-hydroxyethyl)thio]acetic acid (TDGMA) as an intermediate, occurred w ith zero-order rate coefficients ranging from 0 to 6.26 x 10(-6) mol/L .h(-1). Biological toxins hindered this transformation. The major proc ess affecting TDG was biotransformation to form TDGMA and subsequently its biotransformation to TDGA.