Squashing Heavy Metals: Squash’s Potential for Phytoremediation and Safety for Consumption

Pensionnat du Saint-Nom-de-Marie, Montreal QC / Unceded Indigenous lands of the Kanien'kehà:ka and Mohawk Nations

The ability of the red kuri squash (Cucurbita maxima), frequently used in Indigenous cuisine, to absorb heavy metals (HM) while growing was studied to know if the squash is a good plant for phytoremediation (the decontamination of soil with vegetation) and if a fruit grown in a contaminated soil is safe to consume. The presence of HM in soil can be dangerous because of the ability of plants, animals and humans to accumulate them in their organisms and have their bodies’ functioning impaired (Jaishankar et al., 2014, paragr. 1). By analyzing our samples, we want to determine how good of a phytoremediator for lead (Pb), copper (Cu), nickel (Ni) and zinc (Zn) and if this plant is, how HM disperse themselves in the plant and if a fruit grown in contaminated soil is safe to eat. We contaminated the soil with between 300 ppm and 1000 ppm of HM. Students from PSNM collected various samples such as flowers, leaves, stems, soil, roots and fruits to determine if annual plants can decontaminate soil and serve as a safe food source using the IDEAS beamline.