Why is there a great concern about the ‘microbeads’ that are released

Why is there a great concern about the ‘microbeads’ that are released into environment?

They are considered harmful to marine ecosystems.
They are considered to cause skin cancer in children.
They are small enough to be absorbed by crop plants in irrigated fields.
They are often found to be used as food adulterants.
This question was previously asked in
UPSC IAS – 2019
The correct answer is A) They are considered harmful to marine ecosystems.
Microbeads are tiny plastic particles, typically less than 5 mm in diameter, used in various products like cosmetics, toothpastes, and abrasive cleaners. When washed down drains, they enter wastewater systems but are often too small to be filtered out. They are then released into rivers, lakes, and oceans. Once in aquatic environments, microbeads persist for a very long time and pose a significant threat to marine life.
Aquatic organisms, from small zooplankton to fish and birds, can ingest microbeads, mistaking them for food. Ingested plastic can cause physical harm, block digestive tracts, and leach harmful chemicals. Microbeads also absorb pollutants from the surrounding water, concentrating toxins which can then be transferred up the food chain. This biomagnification of toxins is a major environmental concern. The widespread presence and persistence of microbeads in marine environments necessitate efforts to reduce their use and prevent their release. Concerns about skin cancer, absorption by crop plants, or use as food adulterants are not the primary reasons for concern about microbeads in the environment.