Translocation of cadmium in Ocimum basilicum at low concentration of CdSSe nanoparticles

The applications of metal nanoparticles such as quantum dots (QDs) have increased because of their interesting and commercial optical properties. The high production, transport, and commercialization of these nanomaterials increase the probability that they be released to the environment. In plants, phytoextraction is a natural process where metal ions are extracted from the soil for normal plant growth. For commercial crops, it is important to understand the movement of contaminants, especially for aerial parts of edible plants. High translocation rate to aerial plant parts could result in high exposition and ingestion of metals. Ocimum basilicum “basil”, a culinary herb used for centuries, was used to evaluate the translocation rate from roots to shoots and leaves of two cadmium species: ionic (Cd-ionic) and nanoparticles (Cd-QDs). Basil plants were germinated and cultured in an environmental chamber at 27 °C, with 12 h of day light. The results indicate that cadmium is principally stored in the roots after the exposition to Cd-ionic or Cd-QDs. The highest translocation rate of cadmium from roots to shoots and leaves was achieved at the lowest Cd-QDs concentration (25 mg/kg of plant material). The stability of the Cd-QDs in water would favor the absorption and movement of this species inside basil plants.