Validity of new biomarkers of internal dose for use in the biological monitoring of occupational and environmental exposure to low concentrations of b

Validity of new biomarkers of internal dose for use in the biological monitoring of occupational and environmental exposure to low concentrations of benzene and toluene: "Conclusions Our research confirmed the validity of t,t-MA and SPMA for use in the biological monitoring of exposure to low concentrations of benzene. Urinary benzene showed comparable validity to SPMA; both parameters are affected by smoking cigarettes in the hours before urine collection, so it is best to ask subjects to refrain from smoking for 2 h before urine collection. Urinary toluene was found to be a more specific biomarker than SBMA."