Micronuclei and other nuclear anomalies in exfoliated urothelial cells and urinary 8-hydroxy-deoxyguanosine levels among Turkish hairdressers

Abstract

Hairdressers are constantly occupationally exposed to many chemicals have the potential to cause allergies and carcinogenic effects, act as skin and eye irritants and induce oxidative stress and DNA damage. This study aimed to evaluate occupation-induced genotoxicity based on the presence of micronucleus (MN) and other nuclear anomalies in urothelial cells and measure oxidative DNA damage based on the 8-hydroxy-2’-deoxyguanosine level in the urine of Turkish hairdressers. Originality of this study comes from that there was no study on MN and other nuclear anomalies frequencies and oxidative DNA damage in urine samples of hairdressers in the literature. The mean±standard deviation frequency (‰) of micronucleated (MNed) cells was higher in the hairdresser group (n=56) (4.81±7.87, p<0.001) than in the control group (n=56) (0.93±1.85). Nuclear buds were not observed in either group. While the frequency of basal cells was higher in the control group (446.6±106.21) than in the hairdresser group (367.78±101.51, p<0.001), the frequency of binuclear, karyolytic, pycnotic and karyorrhectic cells were higher in the hairdresser group (0.41±0.80, p<0.001; 438.02±118.27, p<0.001; 0.43±0.76, p<0.001; and 47.27±28.40, p<0.001) than in the control group (0.04±0.27, 358.57±95.71, 0.05±0.23 and 24.41±14.50). Condensed chromatins were observed only in the hairdresser group. Specific gravity adjusted 8-hydroxy-2’-deoxyguanosine level was statistically lower in the hairdresser group (908.21±403.25 ng/mL-SG) compared to the control group (1003.09±327.09 ng/mL-SG) (p=0.024). No significant correlation was found between the 8-hydroxy-2’-deoxyguanosine level and the frequency MN. The amount of formaldehyde released during Brazilian keratin treatment was higher than the American Conference of Governmental Industrial Hygienists -Threshold Limit Value (ACGIH-TLV; 0.1 ppm). Similarly, the amount of ethyl acetate released in three salons was above the recommended limit (400 ppm). These findings suggest that hairdressers have an increased risk of genotoxicity and cytotoxicity owing to occupational exposure, regardless of age, working hours, smoking and alcohol consumption.