Abstract The content of readily volatile halogenated hydrocarbons (chlorinated and chlorinated, fluorinated hydrocarbons (VCCs/CFCs)) and the BTEX aromatic substances (benzene, toluene, ethylbenzene and xylene) in municipal solid waste (MSW) was determined by two different methods. Moreover, the emission potential of these substances via the gas and leachate phase was investigated during the different biological degradation phases in the landfill. Trichlorofluoromethane (R11), dichlorodifluoromethane (R12) and dichloromethane (R30) were the dominating halogenated trace substances detected in the MSW. In the acid phase, with some VCCs/CFCs the emittance may take place up to 30% via the water phase. Hexane, benzene, and toluene could be detected in all tests. Toluene often occurred in relatively high concentrations in MSW. It could be shown that R11 degraded into dichlorofluoromethane (R21).