title: Elemental distribution and uptake by watercress (Nasturtium aquaticum) as a function of water quality.
abstract: Watercress (Nasturtium aquaticum), is an edible plant commonly found in Southern Africa, which grows both in terrestrial and aquatic environments. The elemental concentrations in the plant and surrounding water (growth solution) were investigated to determine the plants nutritional value and to establish impact of water quality on elemental uptake by the plant. The concentrations in the leaves, roots and water were analyzed at eight different sites along the east coast of KwaZulu-Natal, South Africa (30.0000° S, 25.0000° E). Elemental concentrations in the leaves/roots (μg g(-1), dry mass) and water exchangeable/total (μg L(-1)) at Verulam (situated in the northern part of KwaZulu-Natal) were: As (1.2/7.5 and 0.053/0.09), Ca (18272/26091 and 0.336/7.15), Cd (0.9/0.8 and 0.004/0.01), Co (37.2/34 and 0/0), Cr (7/35 and 0.003/0.03), Cu (3/19 and 0.016/0.16), Fe (528/4308 and 0.375/0.6), Mg (3444/1141 and 6.4/7), Mn (110/667 and 0/0), Ni (20/63 and 0/0.01), Pb (16/17 and 0.01/0.02), Se (28/11 and 0.003/0.01) and Zn (102/116 and 0.099/0.36). Elemental uptake was controlled by the plant but water quality did have an impact on uptake. Concentrations of metals in the leaves were in decreasing order of Ca > Mg > Fe > Mn > Zn > Cu > Cr > Ni > Pb > Se > Cd > As > Co. The watercress plant was found to be a rich source of essential elements especially Fe and Cr and contained low concentrations of the toxic metals investigated thereby making it safe for human consumption.
authors.affiliation: a School of Chemistry and Physics , University of KwaZulu-Natal (UKZN) , Durban , South Africa.
authors.forename: Kimona
authors.initials: K
authors.lastname: Kisten
authors.forename: Denisha
authors.initials: D
authors.lastname: Gounden
authors.forename: Roshila
authors.initials: R
authors.lastname: Moodley
authors.forename: Sreekantha B
authors.initials: SB
authors.lastname: Jonnalagadda
mesh_terms: D031223:Nasturtium / Q000737:chemistry / Q000378:metabolism*; D018515:Plant Leaves / Q000737:chemistry / Q000378:metabolism; D013019:South Africa; D014131:Trace Elements / Q000737:chemistry / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism*; D060753:Water Quality
chemical_list: D014131:Trace Elements; D014874:Water Pollutants, Chemical
keywords: ICP-OES; microwave digestion; nutrition; recommended dietary allowance