Addendum to Toluene

In 2017, the German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area derived a BAT value (biological tolerance value) for toluene [CAS NO. 108‐88‐3] in urine to characterize the internal exposure at the workplace. Available publications are described in detail. The evaluation of the BAT value was based on the relationship between toluene uptake by inhalation at the level of the MAK value and the corresponding urinary excretion rate of unmetabolized toluene. An eight‐hour exposure to the present MAK value of 190 mg toluene/m3 correlated with a mean urinary toluene concentration of approximately 75 µg/l. Therefore, a BAT value of 75 µg toluene/l urine was evaluated. Sampling time is at the end of exposure or the end of the working shift.