Vol.:(0123456789) 1 3 Aerosol Science and Engineering https://doi.org/10.1007/s41810-022-00163-4 REVIEW A Comprehensive Review on the Classifcation, Uses, Sources of Nanoparticles (NPs) and Their Toxicity on Health Laxmi Kant Bhardwaj 1,3  · Prangya Rath 1  · Moharana Choudhury 2 Received: 5 July 2022 / Revised: 5 September 2022 / Accepted: 11 October 2022 © The Author(s) under exclusive licence to Institute of Earth Environment, Chinese Academy Sciences 2022 Abstract Nanotechnology (NT) refers to the generation and application of nanoparticles (NPs). Research in NT has been ongoing for several decades and has resulted in a wide range of materials at the nano-scale. Globally, NPs serve various domestic, phar- maceuticals, aviation, textiles, and other industrial purposes. These particles are currently used in kitchen utensils, medical applications, energy-related research, aircraft, etc. The future of our planet depends on NT. Numerous molecular indicators of genetic and autoimmune diseases, malignant tumors, and a wide range of other disorders can currently be diagnosed using NPs. Drug delivery to specifc tissues and organs with controlled drug release and accumulation parameters is achieved through NPs. In addition, NPs have been used as active components in some cases. For example, photodynamic therapy’s incorporation and heating are photosensitizers and hyper-thermic tumor killing through NPs. Despite numerous benefciary use and economic success of NPs, their toxic efects on terrestrial and aquatic ecosystems have also gained attention. Exces- sive exposure to NPs in sectors, such as agriculture, industry, etc. has generated negative health efects in humans. The review highlights about NPs in great detail. The paper discusses their sources, usage, toxicity and health efects, transportation, analysis, and treatment. It represents a summary of recent research developments and achievements in the feld of NT and substantial gap areas that need to be addressed. Keywords Nanotechnology (NT) · Nanomaterials (NMs) · Nanoparticles (NPs) · Nanowaste 1 Introduction NT has gained more attention in the last decades, and the essential components are NPs which are from 1 to 100 nm in size. Nano drives from the Greek word Nanos, meaning a dwarf. Hasan (2015) described the NPs and stated that these particles are made up of metal, carbon, and metal oxides or organic matter. They show the unique chemical, biological and physical properties at the nano-scale. They have at least one dimension that does not exceed 100 nm. Cho et al. (2013) stated that NPs could difer from various dimensions in sizes, and shapes. These particles can have a zero dimension where the breadth, height, and length are fxed at a single point, for example, nanodots while graphene has one dimension with one parameter. Carbon nanotube has two dimensions with two parameters (breadth and length) while gold NPs have three dimensions with breadth, height, and length. These particles have distinctive properties and may difer in size, shape, and structure. They may be spheri- cal, tubular, conical, hollow core, fat, cylindrical, etc. or irregular. The surface of the particles can be irregular or uniform with variations. They have three layers: (a) sur- face layer, which may be functionalized with a variety of metal ions, small molecules, polymers, and surfactants, (b) shell layer, which is a chemically diferent material from the core, (c) core, it is the central portion of the NPs and known as NPs itself (Shin et al. 2016). Machado et al. (2015) stated that some particles are amorphous or crystalline, with multi- or single-crystal solids either loose or clustered. These particles have a high surface charge density. They show sensitivity and reactivity to several * Laxmi Kant Bhardwaj bhardwaj.laxmikant@gmail.com 1 Amity Institute of Environmental Toxicology, Safety & Management (AIETSM), Amity University, Noida 201303, Uttar Pradesh, India 2 Amity Institute of Environmental Sciences (AIES), Amity University, Noida 201303, Uttar Pradesh, India 3 Environmental Management and Research Division, Voice of Environment (VoE), Guwahati 781034, Assam, India