Chloronitrobenzenes (CNBs) are important intermediates for the production of dyes, pesticides, rubber chemicals, and drugs. 2CNB and 4CNB are possible human carcinogens. Therefore, it is important to develop methods to biomonitor people exposed to these occupational and environmental pollutants. We developed a method to determine hemoglobin (Hb) adducts of CNBs. Nitrobenzenes and the resulting arylamines yield the same sulfinamide adducts. Therefore, after base hydrolysis of the isolated Hb the corresponding arylamines are released and quantified by GC-MS. The method was applied to monitor 39 Chinese workers exposed to CNB and 15 control workers from the same factory. The determined Hb adduct levels were compared to the measured air levels, the clinical blood and urine parameters, and health effects identified in the workers. The median Hb adduct levels resulting from exposure to 2CNB and 4CNB were 82.9 and 1013 pg/mg of Hb, respectively. The median air concentrations determined from personal samplers were 0.37 and 0.87 mg/m3 for 2CNB and 4CNB, respectively. The air levels did not correlate with the Hb adduct levels. The median Hb adduct levels were higher in workers with fatigue, eye irritation, splenomegaly, and cardiovascular effects. Most negative urinary clinical parameters were present at higher median Hb adduct levels. The clinical blood parameters decreased at higher adduct levels. The daily dose was estimated from the Hb adduct levels and used to estimate the cancer risk.
Bibliographical noteFunding Information:
The present study was carried out at the Hospital Marqués de Valdecilla, University of Cantabria, Santander, Spain, under the following grant support: Instituto de Salud Carlos III PI020499 , PI050427 , PI060507 , Plan Nacional de Drogas Research Grant 2005— Orden sco/3246/2004 , SENY Fundació Research Grant CI 2005-0308007 and Fundación Marqués de Valdecilla API07/011 . The Instituto de Salud Carlos III, the Plan Nacional de Drogas, the SENY Fundació and the Fundación Marqués de Valdecilla had no further role in the study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the paper for publication.