Biological monitoring of N, N-dimethylformamide. Reference value for N-methylcarbamoyl adduct at the N-terminal valine of globin as a biomarker of chronic occupational exposure.

Objectives: The recently identified metabolic product of the industrial solvent N, N-dimethylformamide (DMF), the N-methylcarbamoyl adduct at the N-terminal valine of globin, can be determined after chemical conversion to 3-methyl-5-isopropylhydantoin (MVH). Due to prolonged persistence of the adduct in human erythrocytes (lifetime: 4 months), MVH is a suitable biomarker of integrated exposure to DMF over a period of several months. Here we propose a reference value for MVH, used for biological monitoring of chronic occupational exposure to DMF.

Improved gas chromatographic-mass spectrometric determination of the N-methylcarbamoyl adduct at the N-terminal valine of globin, a metabolic product of the solvent N,N-dimethylformamide.

A sensitive method for determination of the N-methylcarbamoyl adduct at the N-terminal valine of globin, a new metabolic product of the industrial solvent N,N-dimethylformamide (DMF), has been developed and validated. The method includes conversion of the adduct by the Edman degradation to 3-methyl-5-isopropylhydantoin (MVH), which is followed by optimized gas chromatographic analysis with mass spectrometric detection at m/z 114. The recovery of MVH from terminal N-methylcarbamoylvaline was determined using a model dipeptide to be 90%.