Evolutionary age of repetitive element subfamilies and sensitivity of DNA methylation to airborne pollutants

Table 1 Characteristics and exposure levels of the study participants

Study 1^a Exposure to metal-rich particulate matter (PM)			Highly-exposed steel workers (n=20)	Low-exposed controls (n=20)
	PM₁₀ [μg/m³]	Mean ± SD	203.7 ± 22.9	100.9 ± 28.9
	PM₁₀ [μg/m³]	Range	[152.2 ; 227.9]	[73.7 ; 150.0]
	Participants’ characteristics	Age [Years], mean ± SD	42.4 ± 7.9	37.8 ± 3.0
	Participants’ characteristics	Ex/current smokers, n (%)	12 (60)	14 (70)
Study 2^b Exposure to air benzene			Gas station attendants (n=20)	Low-exposed controls (n=20)
	Air benzene [μg/m³]	Mean ± SD	78.6 ± 42.5	7.0 ± 5.5
	Air benzene [μg/m³]	Range	[31.2 ; 180.1]	[4.2 ; 23.0]
	Participants’ characteristics	Age [Years], mean ± SD	39.9 ± 11.2	39.7 ± 10.4
	Participants’ characteristics	Ex/current smokers, n (%)	7 (35)	5 (25)
Study 3^c Exposure to traffic-derived elemental carbon			Truck drivers (n=20)	Low-exposed controls (n=20)
	Elemental carbon [μg/m³]	Mean ± SD	21.3 ± 4.7	13.4 ± 2.1
	Elemental carbon [μg/m³]	Range	[16.6 ; 35.6]	[7.8 ; 16.1]
	Participants’ characteristics	Age [Years], mean ± SD	35.2 ± 5.1	33.4 ± 6.0
		Ex/current smokers, n (%)	8 (40)	6 (30)

The participants were recruited from different occupations and divided in high- and low-exposed group according to their personal levels of exposure.
^a Steel workers with Particulate Matter with aerodynamic diameter <=10 μm [PM₁₀] >152.2 μg/m3 in the highly-exposed group; steel workers with PM₁₀<150.0 μg/m3 in the low-exposed control group.
^b Gas station attendants in the highly-exposed group; indoor office workers in the low-exposed control group.
^c Truck drivers in the highly-exposed group; indoor office workers in the low-exposed control group.

ISSN: 1743-8977