Hazardous organic compounds in urban municipal solid waste from a developing country

Fresh and partially decomposed municipal solid waste (MSW) collected from three places in Chennai city, viz., a residential collection point and two dumping grounds (Kodungaiyur and Perungudi) were screened for hazardous organic pollutants. Toxicity Characteristics Leaching Procedure (TCLP) using a Zero Headspace Extractor (ZHE) followed by further extraction by solvent separation using n-hexane containing 15% di-ethyl ether was performed and the organic extract obtained was qualitatively screened by GC-MS. 28 different types of higher alkanes and their derivatives, 7 types of C6-C8 fatty acids and their esters, 7 different phenolic compounds including alkylated phenols and degradation products and 5 phthalate compounds occurred in a majority of the analysed samples. 17 other organic compounds such as carboxylic acids, chloroform, phosphate, pharmaceutical chemicals etc. were also detected. Among these compounds, phenolics and phthalates are highly hazardous in nature and occurred in relatively higher concentrations. Hazardous compounds like p-cresol, di-butyl, mono butyl and di-ethyl pthalates were found in concentrations more than 200mg/kg in MSW.