There is a worldwide hazard with microplastics (MPs), plastic production units less than 5 mm, as it increases with the increase in output (>380 million tons/year), which is even division into micro- and nanoplastics. This is a review of over 200 peer-reviewed articles through systematic database searches that combines both experimental, modeling and observational data to help fill knowledge gaps in MP migration, transformations, bioavailability, and health risks in aquatic, terrestrial, and atmospheric environments. Results indicate heterogenous distributions: coastal clumps (e.g., 0.011 +- 0.017 items/m3 oceans), bioturbation-induced soil penetration (600 particles/kg), and peaks in wet season. Prevalent (less than 100 mm) fragments/fibers of polyethylene/polypropylene support wind/river transport and sorption of contaminant. Losses Phthalates are lost through transformations by photo-oxidation, abrasion, and biofilms leading to enhanced ecotoxicity via trophic magnification. Bioaccumulation, endocrine disruption, oxidative stress, and chronic illnesses phenotypes are all potential risks of human exposure, which primarily occurs through the ingestion of fish (millions of particles per week through the ocean) pathways. This framework gives greater emphasis on ecological back-human associations whereby there is routine of such ways, prognostic models and ameliorations such as waste curbs and biodegradables to conserve the surroundings and health.