The efficiency of almond shell ( Amygdalus communis L.) bio-sorption in reduction of heavy metals (lead, cadmium, arsenic, and nickel) from parsley ( Petroselinum crispum )

The increasing pollution of the environment by toxic metals has become a public concern. Heavy metals may enter the plant through the soil where agricultural and horticultural crops are grown. Many methods have been investigated to solve this problem. As a new method, the almond shell has been used for the bio-sorbent of heavy metals in this study. Almond shells untreated and treated with phosphoric acid at different concentrations were added to the soil of the studied plant. Harvested parsley samples were prepared according to AOAC standards. The amount of heavy metals in parsleys were measured with an atomic absorption spectrometer. The results showed positive effects of almond shell, treated with 1% phosphoric acid, and added to soil at 10% (w/w) concentration. Results indicated a 93% reduction in lead of contaminated parsley. Bio-sorbents start their activity as soon as they are added to the soil and continued without the conflicting and destructive effect of the environment.