Long-term exposure to commercially available sunscreens containing nanoparticles of TiO2 and ZnO revealed no biological impact in a hairless mouse model

Table 3 Mean concentrations of Zn in tissues (wet mass) from untreated mice, and treated mice receiving UVR only, or ZnO sunscreen (± UVR) in Series 1

	Group ID	Sunscreen	UVR (kJ/m²)	μg/kg	Mean μg/g ± SEM
	Group ID	Sunscreen	UVR (kJ/m²)	μg/kg	Skin	Brain	Liver	Spleen	Kidney	Lung
Series 1	Control-UVR	None	None	Zn	14.5 ± 0.7	12.2 ± 0.8	19 ± 1	17.4 ± 0.5	14.8 ± 0.7	16.9 ± 0.5
	Control + UVR	None	29	Zn	13 ± 2	15 ± 3	20 ± 1	17.6 ± 0.6	15.7 ± 0.8	16.6 ± 0.6
	ZnO-UVR	ZnO	None	Zn	82 ± 9^a	12.1 ± 0.6	21 ± 1	18.2 ± 0.1	16.6 ± 0.6	16.1 ± 0.4
	ZnO + UVR	ZnO	29	Zn	73 ± 10^a	13 ± 1	21 ± 1	17.3 ± 0.5	17.3 ± 0.7	16.4 ± 0.4

The practical quantification limit of Zn was 0.4 μg/kg; n = 5 for all tissues in all groups except for Control + UVR Skin, for which n = 4
SEM Standard Error of the Mean
^aSignificantly different from untreated mice (Control-UVR)

ISSN: 1743-8977