Department of Chemistry, Himachal Pradesh University, Shimla-171 005, Himachal Pradesh, India E-mail : dksharma_dk@rediffmail.com Fax : 91-177-2633014 Govt. P.G. College, Sarkaghat-Mandi-175 024, Himachal Pradesh, India E-mail : nishasharma581@gmail.com Manucript received online 11 February 2014, revised 04 March 2014, accepted 06 March 2014 With a view to evaluate the leaching potential and consequently surface and ground water contamination, the adsorption of anilofos, an organophosphorus herbicide, on five soils of different characteristics has been studied using a batch equilibrium technique. A spectrophotometric methodology based on the reaction of methyl mercaptan, formed from microwave assisted alkaline hydrolysis of anilofos with carbon disulphide and nickel(II) acetate to form methyl isobutyl ketone extractable yellow nickel(II) methyl thioxanthate complex showing λmax at 378 nm has been developed for the purpose. The leaching potential evaluated in terms of ground water ubiquity score (GUS) has values in the range 0.76–0.97 thus classifying it as non-leacher herbicide. If used in recommended dose, it does not represent hazard to ground water contamination.