Microplastics In The Environment Pathways, Impacts, And Removal Technologies

Abstract

Microplastics, defined as plastic particles smaller than 5 mm, have emerged as a pervasive environmental contaminant with profound ecological and human health implications. Their ubiquitous presence across terrestrial, freshwater, and marine ecosystems highlights the complexity of their sources, pathways, and persistence. Microplastics are generated directly as primary particles (e.g., microbeads, industrial abrasives, synthetic fibers) or indirectly through the fragmentation of larger plastic debris. Once introduced into the environment, these particles are transported via atmospheric circulation, riverine systems, and ocean currents, ultimately accumulating in soils, sediments, and aquatic food webs.

The impacts of microplastics are multifaceted, spanning from physical ingestion by biota to chemical toxicity. Numerous studies indicate that microplastics act as vectors for hazardous pollutants such as heavy metals, persistent organic pollutants (POPs), and pathogenic microorganisms. Their ingestion has been linked to impaired growth, reproductive anomalies, and altered feeding behaviors in aquatic organisms, while bioaccumulation raises concerns about trophic transfer and human exposure through seafood, drinking water, and even atmospheric inhalation. The risks are compounded by the microplastics’ long degradation time and widespread dispersal.

Addressing this challenge requires the advancement of effective monitoring frameworks and removal strategies. Traditional wastewater treatment plants capture a significant portion of microplastics, yet complete elimination remains elusive. Emerging technologies such as membrane filtration, advanced oxidation processes, adsorption using biochar or nanomaterials, and biodegradable polymer alternatives show promise in reducing environmental burdens. Furthermore, nature-based solutions such as phytoremediation and the use of microbial consortia are being explored as sustainable approaches. This paper reviews the major pathways of microplastic pollution, evaluates their ecological and human health impacts, and critically examines the effectiveness of current and emerging removal technologies. By integrating scientific evidence with sustainable innovations, the study underscores the urgent need for policy interventions and multidisciplinary collaboration to mitigate microplastic pollution and safeguard ecosystem and public health.