Microplastic as an Emerging Environmental Threat: A Critical Review on Sampling and Identification Techniques Focusing on Aquactic Ecoystem

Plastic is used in large quantities by humans. Most plastic waste ends up in landfills or water bodies through uncontrolled waste disposal. The larger plastics get fragmented into small pieces below 5 mm in size due to harsh environmental parameters, and such fragmented mall particles are called microplastic (microplastic, < 5 mm) or nanoplastic (< 1 mu m) particles. Currently, microplastic particles are present all around us in significant quantities. Over the last few years, researchers have been exploring the impact of microplastic on the environment and living organisms. Due to a large number of variables such as the chemical nature of plastics, size, shape, lack of optical signatures, hydrophilicity/hydrophobicity, changes in environmental conditions, and lack of consensus on sampling and characterizations, it is hard to quantify and understand the role of microplastics on the environment. Here we provide a comprehensive review of the aquatic ecosystem's sampling, purification process, and microplastic analysis. The future road map and challenges for such important parameters under microplastic research are also provided.