title: Assessment of cytogenetic damage in lymphocytes and in exfoliated nasal cells of dental laboratory technicians exposed to chromium, cobalt, and nickel.
abstract: Dental laboratory technicians may be exposed to metal alloys that are used in the production of crowns, bridges and removable partial dentures. These alloys consist of 35-65% cobalt, 20-30% chromium, 0-30% nickel, and small amounts of molybdenum, silica, beryllium, boron and carbon. The aim of this study was to assess whether dental technicians are occupationally exposed to chromium, cobalt and nickel, by analyzing urinary excretion levels of these metals and to investigate the genotoxic effects of occupational exposure associated with dental prostheses production operations by analyzing cytokinesis-blocked micronucleus (CB-MN) frequencies in peripheral lymphocytes and micronucleus (MN) frequencies in exfoliated nasal cells from 27 dental laboratory technicians and 15 control subjects. The differences in the urinary excretion of metals between technicians and controls were statistically significant. The mean (+/-S.D.) CB-MN frequencies ( per thousand ) in peripheral lymphocytes were 4.00 (+/-2.98) among the dental technicians and 1.40 (+/-1.30) among the controls, a statistically significant difference (P<0.005). The mean (+/-S.D.) MN frequencies ( per thousand ) in nasal cells were 3.50 (+/-1.80) among the dental technicians and 1.19 (+/-0.53) among the controls, which was also a statistically significant difference (P<0.005). There was a significant correlation between duration of exposure and MN frequencies in lymphocytes (r=0.642, P<0.01), but not in nasal cells of technicians. Our data reveal that in vivo exposure to chromium, nickel and cobalt metals is evident and that this occupational exposure may contribute to the observed genotoxic damage in two types of cells, e.g. lymphocytes and exfoliated nasal cells. However, it cannot be determined which compound(s) are responsible for the genotoxic damage observed in this study.
authors.affiliation: Department of Toxicology, Faculty of Pharmacy, Gazi University, 06330 Hipodrom, Ankara, Turkey. sburgaz@farma.net.tr
authors.forename: Sema
authors.initials: S
authors.lastname: Burgaz
authors.forename: Gonca C
authors.initials: GC
authors.lastname: Demircigil
authors.forename: Meltem
authors.initials: M
authors.lastname: Yilmazer
authors.forename: Nusret
authors.initials: N
authors.lastname: Ertaş
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Kemaloglu
authors.forename: Yavuz
authors.initials: Y
authors.lastname: Burgaz
mesh_terms: D000293:Adolescent; D000328:Adult; D002857:Chromium / Q000009:adverse effects / Q000652:urine; D003035:Cobalt / Q000009:adverse effects / Q000652:urine; D020732:Cytogenetic Analysis; D003722:Dental Alloys / Q000009:adverse effects* / Q000032:analysis*; D017266:Dental Prosthesis / Q000009:adverse effects; D017267:Dental Prosthesis Design; D003800:Dental Technicians; D004784:Environmental Monitoring / Q000379:methods; D006801:Humans; D007754:Laboratories, Dental; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000187:drug effects* / Q000473:pathology; D008297:Male; D017056:Medical Laboratory Personnel; D015162:Micronucleus Tests; D008875:Middle Aged; D009297:Nasal Mucosa / Q000187:drug effects* / Q000473:pathology; D009532:Nickel / Q000009:adverse effects / Q000652:urine; D016273:Occupational Exposure / Q000009:adverse effects* / Q000032:analysis; D012016:Reference Values; D000078329:Workforce
chemical_list: D003722:Dental Alloys; D002857:Chromium; D003035:Cobalt; D009532:Nickel