(1) Fuels such as petroleum are mixtures of various hydrocarbons, and may contain benzene, toluene, xylene , and styrene, and other components.(2) But many other chemicals linked to reproductive health problems, including xylene , trichloroethylene, phenols, and acetone, remain in use.(3) But since the early 1920s, the oil companies have been blocking ethanol use - while using toxic substance like lead, benzene, toluene and xylene .(4) Petroleum fuels contain several toxic compounds, including benzene, toluene and xylene - all considered carcinogens.(5) If you do insist on using solvents, avoid low-flash point solvents like gasoline, xylene , lacquer thinner, etc. which are dangerously flammable.(6) It was unpromising stuff, but Hofmann and others had discovered that by distillation one could separate from it several carbon-rich, odorous organic compounds such as benzene, toluene, xylene , and phenol.