Benzene is a widely diffuse solvent (atmosphere, cigarette smoke, some foods); in the industrial enviroment benzene is currently present at concentrations of ppm. A valid method of biological monitoring that is easy to perform is needed for assessing occupational and non-occupational exposures. A new method has been developed to evaluate low concentrations of benzene in urine samples by means of a 'dynamic' headspace (50 ml of urine in a 120 ml vial). The urine is saturated with anhydrous Na2SO4 in order to support the entrance of benzene in the air over the urine. The solvent is stripped from the urine surface and concentrated on an adsorbent substrate (Carbotrap 100 tube) by means of a suction pump (150 ml/min). A simultaneous intake of filtered air through a charcoal tube allows wash-up of the headspace. Benzene is thermically desorbed and injected in a column (Thermal tube desorber - Supelco; 370°C thermal flash; borosilicate capillary glass column SPB-1 60 m length, 0.75 mm I.D., 1μm film thickness; G.C. Dani 8580 - DID) The detection limit of the method is about 50 ng/l and the variation coefficient is 4.7%. The method was checked on urine samples of 5 non-smokers and 5 smokers: mean values of 135 and 944 ng/l respectively were obtained. A further analysis on urine samples of 60 smokers revealed a significant relationship (p3) (r=0.763).
|Translated title of the contribution||A method for measuring urinary benzene and its use in monitoring low-level exposure|
|Number of pages||12|
|Journal||Medicina del Lavoro|
|Publication status||Published - 1990|
ASJC Scopus subject areas
- Public Health, Environmental and Occupational Health