Towards a biological monitoring guidance value for acrylamide

•We report a study of workers at a UK acrylamide production plant.•Biological monitoring data (urine metabolites and haemoglobin adducts) are given.•Their relationship with environmental (air and hand wash) levels were investigated.•We propose urinary acrylamide-mercapturic acid as the preferred biomarker.•A guidance value is proposed. Acrylamide is classified as a potential human carcinogen and neurotoxicant. Biological monitoring is a useful tool for monitoring worker exposure. However, other sources of exposure to acrylamide (including cigarette smoke and diet) also need to be considered. This study has performed repeat measurements of the urinary mercapturic acids of acrylamide (AAMA) and its metabolite glycidamide (GAMA) and determined globin adducts in 20 production-plant workers at a UK acrylamide production facility. The relationship between biomarker levels and environmental monitoring data (air levels and hand washes) was investigated. Good correlations were found between all of the biomarkers (r2=0.86–0.91) and moderate correlations were found between the biomarkers and air levels (r2=0.56–0.65). Our data show that urinary AAMA is a reliable biomarker of acrylamide exposure. Occupational hygiene data showed that acrylamide exposure at the company was well within the current UK Workplace Exposure Limit. The 90th percentile of urinary AAMA in non-smoking production-plant workers (537μmol/mol creatinine (n=59 samples)) is proposed as a possible biological monitoring guidance value. This 90th percentile increased to 798μmol/mol if smokers were included (n=72 samples). These values would be expected following an airborne exposure of less than 0.07mg/m3, well below the current UK workplace exposure limit of 0.3mg/m3. Comparison of biomarker levels in non-occupationally exposed individuals suggests regional variations (between UK and Germany), possibly due to differences in diet.