Does the Low-level occupational exposure to volatile organic compounds alter the seasonal variation of selected markers of oxidative stress? A case–control study in nail technicians

Table 1 Characteristics of the groups of subjects involved in the study

	“Hot” season (May-July)		“Cold” season (November-February)
Feature	Nail Technicians	Controls	Nail Technicians	Controls
Total number	66	101	79	44
Age [years]	33 [28–41]	32 [26–42]	34 [27–42]	34 [27–42]
Smoking status [never/ever]	26/40 [0.39/0.61]^*	69/32 [0.68/0/32]	42/37 [0.53/0.47]	29/15 [0.66/0.34]
Pack-years	0.15 [0.0–22.5]^**	0.0 [0.0–25.0]	0.0 [0.0–13.5]	0.0 [0.0–3.8]

Numerical data for age and pack-years presented as median [range]. Smoking status [never/ever-smokers] expressed as absolute [relative] counts. Age and pack-years were tested for significant differences among the groups using the Kruskal-Wallis H test with subsequent post-hoc comparisons performed using the z test. Smoking status was tested for significant differences among the groups using the log-linear analysis of contingency tables
^* p < 0.0005 (nail technicians vs. control subjects during the “hot” season)
^** p < 0.01 (nail technicians vs. control subjects during the “hot” season)

ISSN: 1745-6673