Explanation:

Microplastics are defined as synthetic solid particles sized ranging from 1 micrometre to 5 millimetre (mm), which are insoluble in water.

Reasons behind this:

=> Untreated sewage from many cities along the river’s course.

=> Industrial waste and religious offerings wrapped in non-degradable plastics pile pollutants into the river as it flows through several densely populated cities.

=>The plastic products and waste materials released or dumped in the river break down and are eventually broken down into microparticles.