Muneeba Shaheen

Toxic and some essential metals in medicinal plants used in herbal medicines: A case study in Pakistan

The levels of some heavy metals in eight different medicinal plant samples along with soils were collected from two different locations from salt range of Punjab, Pakistan in order to evaluate those vital metals involved in human health implications. These plant species were: Dodonaea viscosa, Withania somnifera, Solanum nigrum, Calotropis gigantea, Mentha spicata, Paganum hermala, Cannabis sativa, Adhatoda vasica, especially those used in the treatment of diseases and their long term usage. The evaluated metals were cadmium (Cd), Nickel (Ni), Chromium (Cr) and lead (Pb). Atomic absorption spectrophotometry (wet digestion) was used for the analyses, and content of metals per sample was expressed as mg/kg. The analysis of variance revealed that there were significant effects of site variation on medicinal species in Ni and Cr contents while the opposite were observed in case of Pb and Cd at location I. The Ni concentrations found in medicinal plants varied significantly while Pb, Cd and Cr were evident as non significant at location II. There was positive non significant correlation of Pb and Cr among soil and plant while negative non significant for Ni and Cd at both locations. The findings suggest that the use of these plant species for the management of diseases will not cause heavy metal toxicity and may be beneficial to the users in cases of micronutrient deficiency, as these metals were found to be present in readily bioavailable form.

Effect of different doses of urea on the uptake of cadmium from soil by Brassica napus : A case study in Sargodha, Pakistan

The present investigation was conducted to study the effect of different doses of urea on cadmium uptake by canola ( Brassica napus L.) applied in full and split doses. Nine different treatments of urea used were: 0 (control), 60, 90, 120 and 150 kg/ha applied to soil as full doses before sowing, and 60, 90, 120, and 150 kg/ha applied as two equal splits; the first was before sowing, while the second was before flower initiation. Samples of soil were taken just after mixing the appropriate dose of urea, whereas those of stems and leaves were taken at the vegetative stage. Cadmium (Cd) concentrations in soil, stems and leaves samples were determined unconnectedly. Based on the data recorded, it was concluded that all the treatments had significant effect on Cd concentrations in soil, leaves, stems, roots and pods. The mean Cd value in soil, leaves and stem ranged from 0.84 to 1.33, 0.32 to 1.07 and 1.27 to 1.69 mg kg -1 dry weight, respectively. While in roots and pods, Cd concentration varied from 1.31 to 1.77 and 1.05 to 1.36 mg kg -1 , respectively. The mean Cd level in soil and plant body was much lower than the critical level reported by different researchers, thus an additional supplementation of Cd is required to meet the needs of plants. Mineral supplements with rational amount of Cd sources are suggested to avoid complications caused by Cd deficiency as well as to achieve an optimal animal production of ruminants being reared on the pasture. Key words : Brassica , cadmium, forage, soil, Pakistan