Effects of environmental benzene: micronucleus frequencies and haematological values in traffic police working in an urban area.
Among the toxic chemicals present in the ambient air of urban centres, benzene raises particular concern due to its haematoxicity and leukaemogenic hazards, probably related to clastogenic factors. However, little is known about the health risks associated with environmental--rather than industrial--exposure to benzene. We analysed micronucleus (MN) frequencies in peripheral lymphocytes by use of the cytokinesis-block technique, and haematological parameters among 49 traffic police and 36 indoor workers (controls) in the city of Bologna. The analysis of urban air provided by a municipal air-quality monitoring station indicated that the levels of environmental benzene were often above the recommended threshold level (10 microg/m3) whereas other pollutants--nitrogen oxides, polycyclic aromatic hydrocarbon compounds, total suspended particulate matter, carbon monoxide, sulfur dioxide--did not exceed the maximum atmospheric concentration established for air-quality standards. Mean levels of individual airborne benzene exposure--as measured by personal devices worn during 4-h morning work-shifts--were six-fold higher in the traffic police than in controls (P=0.001). While no significant difference in haematological parameters was found between the two groups, MN frequency was significantly higher among the traffic police than in indoor workers (P=0.001). Among the study population, MN frequency was found to increase with age, but no influence was observed for gender or smoking. Although it cannot be excluded that the increase of MN frequency observed in traffic police could also depend, apart from benzene, on the complex mixture of pollutants encountered in urban air, our data indicate that elevated personal benzene exposure could represent a genetic risk. The analysis of biomarkers of genetic damage in subjects particularly exposed to environmental benzene deserves careful study.
Maffei
Francesca
F
Department of Pharmacology, University of Bologna, via Irnerio 48, 40126 Bologna, Italy. francesca.maffei@unibo.it
Hrelia
Patrizia
P
Angelini
Sabrina
S
Carbone
Fabio
F
Cantelli Forti
Giorgio
G
Barbieri
Anna
A
Sanguinetti
Giovanni
G
Mattioli
Stefano
S
Violante
Francesco Saverio
FS
D000328:Adult; D000393:Air Pollutants / Q000633:toxicity*; D001554:Benzene / Q000633:toxicity*; D016022:Case-Control Studies; D004249:DNA Damage; D005260:Female; D006403:Hematologic Tests; D006801:Humans; D007558:Italy; D008214:Lymphocytes; D008297:Male; D015162:Micronucleus Tests; D017720:Molecular Epidemiology; D016273:Occupational Exposure; D016495:Police; D018570:Risk Assessment; D014186:Transportation; D014505:Urban Population; D001335:Vehicle Emissions
D000393:Air Pollutants; D001335:Vehicle Emissions; D001554:Benzene