RESUMO
A comprehensive approach to biological monitoring of 44 workers occupationally exposed to styrene in a hand lamination plant was performed by using several end-points: styrene in workplace air, styrene in exhaled air, styrene in blood, DNA strand breaks (SBs) and oxidised bases in mononuclear leukocytes, chromosomal aberrations in lymphocytes, immune parameters and genotyping of polymorphic genes of some xenobiotic-metabolizing enzymes (CYP 1A1, EPHX, GSTM1 and GSTP1). We found a significantly higher number of DNA SBs, measured by a modified comet assay, in mononuclear leukocytes of the styrene-exposed workers compared with results from 19 unexposed controls (P<0.001). A fairly strong correlation was observed between SBs and years of exposure (P<0.001, r=0.545). The styrene-exposed workers also showed a significantly increased frequency of chromosomal aberrations (P<0.0001 for highly exposed group, P<0.004 for medium-exposed group, and P=0.0001 for low-exposed group). The proliferative response of T-lymphocytes stimulated with concanavalin A was significantly suppressed in people exposed to styrene (P<0.05). We recorded a significant increase of the percentage of monocytes in differential white blood cell counts in the exposed group (P<0.05). Using flow cytometry, we found an increased expression of adhesion molecules CD62L, CD18, CD11a, CD11b, CD49d and CD54 in the exposed workers as compared with the control group (P<0.05).
Assuntos
Monitoramento Ambiental/métodos , Exposição Ocupacional , Estireno/toxicidade , Adulto , Poluentes Ocupacionais do Ar/toxicidade , Biomarcadores , Estudos de Casos e Controles , Moléculas de Adesão Celular/metabolismo , Aberrações Cromossômicas , Dano ao DNA , Enzimas/genética , Enzimas/metabolismo , Feminino , Genótipo , Humanos , Técnicas In Vitro , Ativação Linfocitária/efeitos dos fármacos , Masculino , Plásticos , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologiaRESUMO
The results of two mutagens are presented in order to demonstrate the sensitivity of a modified Salmonella microsuspension assay (Kado et al. 1983) compared to the standard plate-incorporation assay. The first procedure was 2.4-7.3 times more sensitive in detecting the mutagens, 2-aminoanthracene and sodium 5-(3-nitro-2-furyl)acrylate. Methanol extract and cyclohexane extract from cigarette side smoke enhanced the response in the absence and presence of S9 activation mixture with the TA 98 strain. The cigarette side smoke mutagens were detected in 10 times lower volume samples (0.1 m3 of sampled air) in the microsuspension assay than in the plate incorporation assay.