Urinary levels of trace elements among primary school-aged children from Italy: The contribution of smoking habits of family members

The aims of the present study was to investigate the role of Environmental Tobacco Smoke (ETS) exposure in domestic environment, the smoking policies adopted at home on urinary excretion of 23 trace elements present in tobacco and/or tobacco smoke (Li, Be, B, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Rb, Sr, Cd, Sn, Sb, Te, Cs, Tl, Pb, Bi, U) among a sample of healthy Italian school-aged children. The levels of monitored trace elements in urine samples from 110 children (5-11years) living in a rural area and recruited in a cross-sectional study were measured via inductively coupled plasma mass spectrometry, while information regarding demographic characteristics and ETS exposure of the participants were obtained from questionnaires. Univariate elaborations evidenced that Co and Mn levels increased in children exposed to ETS in domestic environment, but multiple linear regression analyses revealed the independent effect of the habit of cohabitant(s) smoker(s) of smoking at home when children is present on urinary concentrations of Li, Ti, V, Co, Ga and Sr. Besides, we found significant gender- and age-dependency of some monitored elements: females presented higher Cu and Pb levels, but lower Rb levels respect to males, while age displayed a significant negative independent effect on the Cr, Co, Rb, and Sn concentrations, but positive on Ga levels. Finally, u-creatinine was a significant predictor for almost all the analytes, but not for Mn, Cd, Sb, Ga.