[Assessment of occupational exposure to ortho-toluidine using gas chromatography-mass spectrometry]. / Evaluation d'une exposition professionnelle à l'ortho-toluidine par chromatographie phase gazeuse couplée a la spectrométrie de masse.

Ortho-toluidine is a carcinogen aromatic amine. It is in part eliminated as unchanged form and its urine determination allows biologic monitoriing of occupational exposure. We propose a new method simple and fast in gas chromatography mass spectrometry. In the Nord-Pas-de-Calais region, a company initiated destruction and depollution of an old industrialsite.The GS-MS method permits exposition evaluation of workers employed in demolition of a liquid SO2 plant polluted with ortho-toluidine. This plant has been stopped twenty years ago. These results are compared with results of workers without any exposure in the same company. A 5 mL urine sample spiked with internal standard (ortho-toluidine D9) is extracted with hexane. Derivatisation is achieved with anhydrous pentafluoropropionic acid during 30 min at 60 degrees C. Chromatographic separation is performed on a BPX5MS column (25 m x 0.25 mm, 0.25 microm; SGE). Initial column temperature (60 degrees C) is hold 3 min then is raised to 300 degrees C at 25 degrees C/min. Detection is performed with mass spectrometry with negative chemical ionisation with methane. Acquisition is performed in single ion monitoring. Identification ions are 233 ion (m/z) and 213 ion (m/z) with 233 (m/z) used for quantification. Linearity of the method is verified between 0.1 and 100 microg/L. The limit of detection is 0.02 micro/L. Repeatability and intermediate fidelity are satisfactory (CV < 9%). For unexposed workers, urinary concentrations of ortho-toluidine ranged between 0.17 microg/L and 2.46 microg/g creatinine. Urinary concentrations for exposed workers ranged between 26.14 and 462.00 microg/g creatinine and after new action of protection between 2.35 et 20.11 microg/g creatinine. This new GC-MS method is specific and sensitive and allows for urinary determination of ortho-toluidine. Results showed that this method is adapted for biomonitoring as much for unexposed workers to this aromatic amine as for exposed workers.

Peripheral markers (Clara cell protein and alpha-glutathione S-transferase) and lipidoperoxidation (malondialdehyde) assessment in Sprague-Dawley rats instilled with haematite and benzo[a]pyrene.

The literature suggests that the concomitant exposure to polycyclic aromatic hydrocarbons (PAH) and ferric oxide particles could enhance lung cancer incidence in environmental and occupational settings. High levels of tracheobronchial tumours were obtained in hamsters exposed to benzo[a]pyrene (B[a]P) adsorbed onto ferric oxide carrier particles. Therefore, we have assessed the toxic effects of exposure to haematite (Fe2O3) and B[a]P in male Sprague-Dawley rats. Animals were instilled with the chemicals alone (3 mg of Fe2O3 or B[a]P) or in combination (3 mg Fe2O3 + 3 mg B[a]P). Bronchoalveolar lavages (BAL) and biological samples (serum and urine) were collected 48 h after the intoxication. Clara cell protein (CC16) and alpha-glutathione S-transferase (alpha-GST), as peripheral markers of both tracheobronchial epithelial cell integrity and renal dysfunction, were determined in BAL fluid, serum and urine. Malondialdehyde (MDA), a marker of lipid peroxidation, was measured in BAL fluid and serum. We observed a significant increase of CC16 concentrations in BAL fluid after Fe2O3 + B[a]P instillation (p < 0.05) in serum after Fe2O3 and Fe2O3 + B[a]P exposure (p < 0.01) and in urine after B[a]P administration (p < 0.01). Instillation of Fe2O3 + B[a]P produced an increased amount of alpha-GST in BAL fluid (p < 0.01), whereas B[a]P alone caused a significant elevation of alpha-GST in serum and urine (p < 0.01). Moreover, Fe2O3 or Fe2O3 + B[a]P instillation induced a significant increase in MDA levels in BAL fluid (p < 0.01 and p < 0.05). In conclusion, Fe2O3 may have a low pulmonary toxicity. However, B[a]P manifested a rapid and high toxicity in the respiratory tract and kidneys. When B[a]P was adsorbed on haematite particles, both its retention in the respiratory tract and pulmonary toxicity increased.