The proposed bill, known as the "Microplastics Reduction Act," aims to address the growing concern of microplastic pollution in water bodies across the state. It introduces a new chapter, Chapter 19.19, to Title 23 of the General Laws, which includes definitions for key terms such as "microplastics," "manufacturer," and "product." A significant provision of the bill is the prohibition of the sale, distribution, or offering of any product containing intentionally added synthetic polymer microparticles starting January 1, 2029. This restriction does not apply to products that are preempted from regulation by federal law.

Additionally, the bill mandates the Department of Environmental Management, in consultation with the Department of Health, to develop a microplastics testing plan and a statewide microplastics strategy plan. The testing plan must be made public by July 1, 2028, and will outline methods for regularly testing environmental media for microplastics. The strategy plan, due by January 1, 2029, will assess the environmental and health impacts of microplastics, investigate their sources, and provide recommendations for policy changes to mitigate their presence. The act will take effect upon passage.