Pilot study on the naphthalene exposure of German adults and children by means of urinary 1-and 2-naphthol levels

Concentrations of 1- and 2-naphthol were measured in urine of 72 adults and 35 young children from Germany to assess the internal exposure to naphthalene of the general population. Naphthols could be detected in more than 90% of the urine samples. Levels of naphthols (sum of 1- and 2-naphthol) were 4-fold higher in smokers (median: 37.6 mug/g creatinine) compared to non-smoking adults (8.2 mug/g creatinine). On a creatinine basis young children had slightly lower naphthol levels in urine compared with adults (7.5 mug/g creatinine). Preliminary reference values for the sum of 1- and 2-naphthol in urine as means of the 95th percentile are proposed: 41.2 mug/g creatinine (non-smoking adults) and 23.5 mu/g creatinine (young children). It is concluded that 1- and 2-naphthol levels in urine are suitable for human biomonitoring of the naphthalene exposure in environmental medicine.