Characterisation of Engineered Nanomaterials in Nano-Enabled Products Exhibiting Priority Environmental Exposure

Analytical limitations have constrained the determination of nanopollution character from real-world sources such as nano-enabled products (NEPs), thus hindering the development of environmental safety guidelines for engineered nanomaterials (ENMs). This study examined the properties of ENMs in 18 commercial products: sunscreens, personal care products, clothing, and paints-products exhibiting medium to a high potential for environmental nanopollution. It was found that 17 of the products contained ENMs; 9, 3, 3, and 2 were incorporated with nTiO(2), nAg, binaries of nZnO + nTiO(2), and nTiO(2) + nAg, respectively. Commonly, the nTiO(2) were elongated or angular, whereas nAg and nZnO were near-spherical and angular in morphology, respectively. The size ranges (width x length) were 7-48 x 14-200, 34-35 x 37-38, and 18-28 nm for nTiO(2), nZnO, and nAg respectively. All ENMs were negatively charged. The total concentration of Ti, Zn, and Ag in the NEPs were 2.3 x 10(-4)-4.3%, 3.4-4.3%, and 1.0 x 10(-4)-11.3 x 10(-3)%, respectively. The study determined some key ENM characteristics required for environmental risk assessment; however, challenges persist regarding the accurate determination of the concentration in NEPs. Overall, the study confirmed NEPs as actual sources of nanopollution; hence, scenario-specific efforts are recommended to quantify their loads into water resources.