Assessment of the contents of a selected macro, micro and toxic elements in ripen bael fruits and tender shoots of water spinach and sweet potato using XRF and ICP-MS methods

Abstract

Macro and micro elemental nutrient profiles and compositions of toxic heavy metals in food items are important attributes in culinary and nutrition sciences. We selected ripen bael fruits of elite accessions selected for large-scale cultivation in Sri Lanka, Kankong, a green leafy vegetable prone to bioaccumulation of toxic heavy metals (market and commercially available samples) and shoot-tops of sweet potato, an underutilized leafy vegetable to detect the elemental compositions using X-ray fluorescence (XRF) and Inductive Coupled Plasma Mass Spectrometric (ICP-MS) methods. Bael pulp was extracted from ripe fruits and, Kankong and sweet potato shoot-tops were collected. The presence and absence of elements were assessed using XRF. The elemental contents were measured using ICP-MS, and statistically analyzed. Bael and SP samples did not contain toxic heavy metals As and Pb whereas Kankong samples collected from a municipal wastewater drain contained all these toxic elements in large quantities. Kankong samples purchased from open market contained Hg, Cd, As and Cr. It is also noted that Pb separately correlated with Cr, Fe, Co, Zn, Ni and Hg contents in Kankong implying that they are under a common absorption mechanism or coming from a common source in the polluted habitat. The present study concludes that Kankong in Sri Lanka is unsafe for consumption and SP is an alternative to replace Kankong.

Keywords

• green leafy vegetable, bael fruits, kankong, under-utilized leafy vegetable, heavy metals in food, sweet potato as a leafy vegetable