Microplastics are major pollutant distributed widely throughout the Indian marine and freshwater are posing a significant risk to living organisms. World economic forum’s estimation, the world’s oceans will be filled with more plastics than fishes by weight by 2050. The extreme production and use of plastics being lead to plastic waste disposal, and the plastic degrade to microplastic. The growing amount of microplastics will continue to increase microplastic pollution in aquatic environments. Today, it is a major environmental problem because microplastics are less than 5 mm in size and associated with other pollutants that can be accumulated on the body to make health problems and lead to death. Microplastics are directly ingested by organisms from polluted water or indirectly through the contaminated food web. The effects of microplastics are wide-ranging, impacting marine life, fisheries, economics, tourism, plants, marine aesthetics, and human health. This paper review focuses on the microplastic sources, pollution, and its impact in the Indian aquatic environment.

A study was carried out to reveal the growth inhibitory effect of methanol crude extract (MCE) and methanol supernatant extract (MSE) of sea weeds: 1) Gracillaria corticata, 2) Hypnea musciforms, 3) Gelidium micropterum and 4) Hypnea valentiae  against six bacterial pathogens, 1) Pseudomonas aeruginosa, 2) Bacillus licheniformis, 3) Serratia marcescens, 4) Aeromonas hydrophila, 5) Acinetobacter baumanii, 6) Escherichia coli and two fungal strains, 1) Aspergillus niger and 2) Candida albicans respectively. Well diffusion method using zone of inhibition as indicator for growth inhibition was adopted. The results showed that methanol extracts of seaweeds viz., Gracillaria corticata, Hypnea musciforms, and Hypnea valentiae prevented the growth of pathogenic bacteria and fungi. The effect on growth was observed as zone of inhibition, the diameter of which was indicated in the units of a millimeter. The growth of the bacterium, Serratia marcescens was affected by methanol supernatant extract of the three types of seaweeds, Gracillaria corticata, Hypnea musciforms, and Hypnea valentiae, and by the methanolic crude extract of Hypnea musciforms and Hypnea valentiae. However, the growths of other species of bacteria were not controlled by either of the extracts of the seaweeds except, Bacillus licheniformis which was controlled by only Gracillaria corticata. The growth of fungi: Aspergillus niger and Candida albicans were inhibited by the methanol extracts of Gracillaria corticata. Between the two forms of methanolic extracts i.e., supernatant and crude, the efficiency of the supernatant extract was greater than that of crude one. Further, among the three types of seaweeds which showed an effect on the growth of microbes, the level of the zone of inhibition caused by Gracillaria corticata was statistically higher than that of the other two, Hypnea musciforms, and Hypnea valentiae.