Table 1. Statistical analysis of the distribution of the frequency of micronuclei among the analyzed groups according to variation in means and standard deviations on ANOVA and Tukey’s test, significance level p<0.05, Santarem, Para, Brazil 2016 (n=147).

Median	number	Median	Mean±standard deviation
Gas station attendants, non-drinkers, 0 to 5 years	21	5.0	4.5±1.2*
Gas station attendants, drinkers, 0 to 5 years	21	7.0	7.3±2.6*#
Gas station attendants, mouthwash users, 0 to 5 years	21	6.0	5.7±1.8*
Gas station attendants, non-drinkers, 6 to 10 years	21	5.0	4.8±1.6*
Gas station attendants, drinkers, 6 to 10 years	21	7.0	7.3±2.2*#
Gas station attendants, mouthwash users, 6 to 10 years	21	6.0	6.1±2.0*
Controls	21	2.0	1.8±1.3

*Gas station attendants exposed to gasoline fumes, alcohol and mouthwash compared to the control group; there was significant increase in the frequency of micronuclei, p<0.01; #gas station attendants who reported to consume alcohol versus non-drinkers; there was significant increase in the frequency of micronuclei, p<0.01.