Comparative environmental fate and toxicity of copper nanomaterials

N. Zuverza-Mena
Connecticut Agricultural Experiment Station,
United States

Keywords: copper, nanoparticles, fungal, crop plants

Summary:

Copper nanoparticles (Cu NPs) are increasingly being incorporated in marketable items, and eventually entering the environment. Living organisms are prone to be in contact with Cu NPs, and it is important to understand the associated risks. Here, six Cu-based materials were studied: nano Cu (nCu), micro Cu (μCu), nano CuO (nCuO), micro CuO (μCuO), and two Cu-based pesticides with Cu(OH)2. Metabolic effects were found in plants that accumulated Cu and formed reactive oxygen species (ROS), from doses as low as 5-20 mg Cu/plant. In water, copper is released from antifouling paints as Cu ions and particles in the nano and micro-size. Depending on the matrix characteristics, Cu undergo transformations forming mainly insoluble compounds such as CuS. In general, Cu toxicity has been observed to be in the decreasing order as follows: Cu2+ > nano Cu0 > nano Cu(OH)2 > nano CuO > micron-scale Cu compounds. Also, Cu has shown to be more toxic to aquatic organisms than terrestrial ones. This work presents valuable information towards risk assessment for a responsible commercialization of Cu NPs.