Evaluating the effect of age and area of residence in the metal and metalloid contents in human hair and urban topsoils

Abstract

18Monitoring the levels of trace elements in hair can allow estimating the effects of the geographical 19 location and also can provide a notion of the metal body burden. However, the use of human hair is 20 controversial due to different confounding factors that could affect the presence of trace elements 21 in hair. As a result, a comprehensive monitoring study was performed in Alcalá de Henares, one of 22 the major cities in the Madrid Region, Spain. Trace elements have been monitored in urban topsoils 23 and in human hair of two well-defined and healthy groups of population: children (6-9 years) and 24 2 adolescents (13-16 years). The city was divided into four areas or zones with different characteristics 25 to assess the possible effect of the area of residence and the age in the presence of Al, As, Be, Cd, Cr, 26Cu, Hg, Mn, Pb, Sn, Ti, Tl and Zn in soils and hair. There is no current hypothesis that explains the 27 possible effect of the area of monitoring in the distribution of Be, Cr, Ni, Sn and Ti found in these 28 urban soils, maybe because urban soils receive high disturbance and there are many factors 29 involved. The presence of most of the trace elements monitored was significantly higher in the hair 30 of the children population, except for Sn and Zn. This could be attributed mainly to dietary habits. 31Other factors influencing metal content in hair such as environmental factors would have had a 32 minimal effect in the population groups here studied. Finally, none of the levels of trace elements 33 studied in hair were significantly correlated with levels measured in the topsoils of public parks in 34Alcalá

Biomonitoring of Trace Elements in Hair of Schoolchildren Living Near a Hazardous Waste Incinerator—A 20 Years Follow-Up

“…The different results might be attributed to the differences among the respective geographical areas. Furthermore, despite the mean Cr concentration is similar to most levels found in recent literature, Cr concentrations in the urban area of Madrid were approximately 5-fold higher than those of the present study [46]. The mean level of Hg was also higher than the concentrations found in other locations, such as toxic waste disposal sites of Russia [35] and different urban areas [14,47].…”

“…The mean level of Hg was also higher than the concentrations found in other locations, such as toxic waste disposal sites of Russia [35] and different urban areas [14,47]. In contrast, Hg concentrations in children from Tarragona County were lower than those found in other Spanish studies focused on assessing urban and industrial/mining areas [26,46]. The current Mn values were lower than elsewhere, differing notably from those found in Sardinia (Italy) and Russia [34,35,37].…”

“…The concentrations of trace elements in hair of schoolchildren were compared with those of recent studies found in the scientific literature ( Table 5). Most of these investigations are focused on areas with important industrial or mining activities or even in urban zones [11,14,26,30,[34][35][36][37]46,47]. The different results might be attributed to the differences among the respective geographical areas.…”

The impact of lifestyle factors on age-related differences in hair trace element content in pregnant women in the third trimester [pdf]

“…These results are consistent with an earlier investigation that demonstrated a significant decrease in hair Cd and V levels in women aged 20-30 years in comparison to older women (30-40 years; Skalnaya et al, 2016). Similarly, both hair Zn and Cd were characterized by a significant decrease in adolescents in comparison to children (Peña-Fernández et al, 2016). At the same time, no significant group difference in hair Zn levels was detected (Skalnaya et al, 2016).…”