RESUMO
Lead (Pb)-polluted soils pose a serious threat to human health, particularly by transmitting this heavy metal to the food chain via the crops grown on them. The application of novel amendments in Pb-polluted soils can significantly reduce this problem. In this research, we report the effects of various organic and inorganic amendments i.e., bentonite (BN), biochar (BR), lignin (LN), magnesium potassium phosphate cement (CM) and iron hydroxyl phosphate (FeHP), on the Pb bioavailability in Pb-polluted soil, upon Pb distribution in shoots, roots, grain, the translocation factor (TF) and the bioconcentration factor (BCF) of Pb in pea (Pisum sativum L.) grain. Furthermore, effects of the said amendments on the plant parameters, as well as grain biochemistry and nutritional quality, were also assessed. Lead pollution significantly elevated Pb concentrations in roots, shoots and grain, as well as the grain TF and BCF of Pb, while reducing the nutritional quality and biochemistry of grain, plant height, relative water content (RWC), chlorophyll contents (chl a and chl b) and the dry weight (DW) of shoot, root and grain. The lowest Pb distribution in shoots, roots and grain were found with BN, FeHP and CM, compared to our control. Likewise, the BN, FeHP and CM significantly lowered the TF and BCF values of Pb in the order FeHP > CM > BN. Similarly, the highest increase in plant height, shoot, root and grain DW, RWC, chl a and chl b contents, grain biochemistry and the micronutrient concentrations, were recorded with BR amendment. Biochar also reduced grain polyphenols as well as plant oxidative stress. Given that the BR and BN amendments gave the best results, we propose to explore their potential synergistic effect to reduce Pb toxicity by using them together in future research.
RESUMO
BACKGROUND: Despite the high global prevalence of malnutrition, it remains under-treated, or undetected. The high energy nutritional supplements are usually prescribed to promote rapid weight gain. However, there is no consensus on the most effective way to treat mild to moderate malnutrition. METHODS: For identification of articles search engines of the databases OVID, MEDLINE, EMBASE and Pub med were used for papers published from 2003 to 2014 in English language. RESULTS: The total energy intake including the supplements is significantly improved. However, the rate of weight gain by the high energy nutritional supplements in moderately malnourished children is less than the expected weight gain. CONCLUSION: While assessing the impact of the supplementation on child nutritional status, other factors should also be taken into account, including appetite suppression, replacement of habitual food intake and compliance to the intervention.