Evaluation of Toxicological Implications Ascribed to Morphology and Size-Based Platinum Nanoparticles and Its...

Automotive catalytic converters have been used for many years to reduce the amount of harmful substances in the environment. Although they significantly reduce environmental pollutants, catalytic converters are known to increase the environmental loads of PGEs (platinum group elements), which are also detected in exhaust gases as micro and nano-sized particles. PGEs are generally regarded to be harmless for human health; nevertheless, their widespread usage in different applications, particularly in catalytic converters, and the consequent discharge of these elements into the environment, increases the concentration of Pt and Pt NPs in the environment. It also increases the chance of human exposure to Pt and Pt NPs, revealing a new risk factor. Based on the aforementioned concept, the pulmonary toxicity of size and morphology-dependent Pt NPs were investigated in this study, as well as the modulating effect of naringin on pulmonary toxicity imposed by the exposure of Pt NPs. Highly mono-dispersed Pt NPs of varied sizes and morphology were synthesized using the micro-emulsion method. Various techniques were used to characterize the synthesized Pt NPs. The present study aimed to evaluate the toxicity induced due to the exposure of different sizes and morphology-based Pt NPs to the lungs, following oral administration in Wistar rats for 28 days. Due to the continuous exposure of different size and morphology-dependent Pt NPs, the Wistar rats showed weakness and continuous decrease in body weight at different time intervals. Pulmonary toxicity induced due to the exposure of size and morphology-dependent Pt NPs was detected by the change in levels of biochemical markers (SOD, CAT, GSH-Px, and MDA) and pro-inflammatory cytokines (IL-6, IL-1β, and TNF-α). The histological alterations in the lung tissues of Wistar rats, as compared to control, determined the toxicity imposed by their exposure. Furthermore, Naringin, a prominent flavanone glycoside found in many citrus fruits and plants, has been researched for its potential to mitigate the toxic effects of Pt NPs. Naringin was administered intraperitoneally and treatment also continued for 28 days. It was found that the prior exposure of naringin modulated the pulmonary toxicity of size and morphology-dependent Pt NPs. As an outcome of this study, we concluded that it is important to take into account the health risks of Pt and Pt NPs, in order to fully comprehend their environmental fate.