Dietary exposure to essential and toxic trace elements from a total diet study in Lebanese children and adolescents -

Abstract

Some trace elements such as Fe, Cu and Zn are essential micronutrients that need to be consumed in adequate amounts to maintain normal physiological functions. In contrast, dietary exposure to other elements such as Cd, Pb, Hg and As has been associated with toxic and adverse health effects. This highlights the need for dietary exposure studies, which are crucial for risk evaluation, and possibly for the determination of the relationships between adverse effects observed in humans and dietary exposure to particular substances. The objective of this study is to assess, by means of the Total diet study approach, the dietary exposure of Lebanese children and adolescents to four toxic elements (Lead, Cadmium, Arsenic, Mercury) and the dietary intake of three essential micronutrients intakes (Copper, Iron, Zinc) by this population group. The foods that made up the average “total diet” were derived from a previously conducted individual food consumption survey that covered a nationally representative sample of 919 children and adolescents aged 5-19 years in Lebanon. The “market basket” was identified and included 99 food items. The market basket was estimated to provide 1962.96 Kcal-person-day of which 48.40percent, 13.60percent and 37.50percent were provided by carbohydrates, proteins and fats respectively. Foods constitutive of the market basket were collected and prepared as for normal consumption prior to analysis. Analytical quantification was performed using atomic absorption spectrometry. Average daily exposures to Pb (23.77 µg-day), Cd (3.78 µg-day), As (0.19 µg-day) and Hg (2.69 µg-day) were below the toxicological reference values and represented 13percent, 8percent, 0.2percent and 23.75percent of the respective provisional tolerable weekly intake values; however, the 95th percentile exposure level to mercury was close to its PTWI, highlighting the possibility of exceeding the toxicological reference values for this element by children and adolescents who have a high consumption level of fish. The