This is from the EPA
TOLUENE & XYLENE
Toluene (also known as toluol or methylbenzene) and xylene (also known as xylol or dimethylbenzene) are aromatic hydrocarbons found around the home in paints, paint and varnish removers, degreasers, cleaners, lacquers, glues, nail polish, and cement. Because of their excellent ability to dissolve substances, they are often used in insecticides and other pesticides to dissolve the active ingredient. Toluene and xylene are volatile, flammable, and toxic.
Toluene and xylene are irritating to the skin and respiratory tract and may cause liver damage. These aromatic hydrocarbons enter your system through inhalation and ingestion, but are poorly absorbed by the skin. The target organs attacked by toluene and xylene are the central nervous system, eyes, liver, kidneys, and skin. Toluene and xylene are narcotic in high concentrations. Intentional inhaling of these substances can cause headache, giddiness, and a transient euphoria followed by depression. Hallucinations may occur, especially following chronic exposure. Neurological damage occurs from concentrated inhalation of these fumes. Symptoms include fatigue, weakness, confusion, headache, tearing, nervousness, muscular fatigue, insomnia, dermatitis, an intolerance of light.