The safety and toxicity of MPA-CdTe quantum dots in legume plants

Magister Scientiae - MSc (Biotechnology)The expansion of nanotechnology, resulting in multitudes of consumer and industrial products, causes concern amongst the scientific community regarding the risks associated with the release of nanomaterials into the environment and its subsequent effects on plants. Therefore, the focus of this study was aimed at investigating the effects of MPA-capped CdTe and carbon QDs on legumes plants namely P. vulgaris and G. max. Fluorescent imaging revealed that QDs were translocated from the roots to the aerial parts of the plant and accumulated in the edible parts of P. vulgaris. Subsequent physiological and biochemical tests revealed that both QD types induced oxidative stress as biological markers for stress including lipid peroxidation and cell death were elevated. In addition, carbon QDs displayed lower toxicity in comparison to MPA-CdTe QDs, but still possessed the ability to induce oxidative stress in plant cells. However, the effects were more pronounced in G. max in comparison to P. vulgaris; and more so with MPA-CdTe QDs than carbon QDs. Furthermore, MPA-CdTe and carbon QDs altered the concentrations and translocation of essential macro and microelements that are required for plant growth and development. This may have detrimental effects on crop productivity and yield, with negative implications on food quality and food security