The onset of the COVID-19 era has presented substantial challenges to both environment and human life. It resulted in an increase in the production of biomedical waste, which subsequently ended up in aquatic bodies and terrestrial ecosystems due to improper disposal. By means of sunlight, oxidative and thermal processes, and biodegradation, biomedical waste that contains plastic can be transformed into microplastics (MPs, <5 mm). MPs that contain additives and contaminants, such as metals, that are harmful to a variety of aquatic and terrestrial organisms, including humans. Often, the bioaccumulation of MPs in organisms is transferred across the trophic level in the global food web. Consequently, the objective of this chapter is to offer a glimpse into the source, quantity, and fate of biomedical waste, as well as the recent increase in MPs and their detrimental effects on aquatic and terrestrial organisms. The ingestion, inhalation, and dermal contact of MPs in humans result in a variety of chronic diseases that affect multiple organs in the digestive, respiratory, and reproductive systems. This chapter also underscores the importance of implementing stringent policies to prevent future severe situations and implementing effective waste management strategies for the consumption of biodegradable products. Communities may simultaneously prioritize public health safety and environmental and human resilience by incorporating pandemic-generated wisdoms. In order to mitigate environmental and human health hazards, it is imperative to regulate and oversee biomedical waste in order to reduce MPs contamination.