Assessment of greenwashing, degradation and toxicity of biodegradable plastics sold in Brazil

• Grant number: 21/14639-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Effective date (Start): October 01, 2022
• Effective date (End): March 31, 2026
• Field of knowledge: Physical Sciences and Mathematics - Oceanography - Biological Oceanography
• Principal Investigator: Ítalo Braga de Castro
• Grantee: Beatriz Barbosa Moreno
• Host Institution: Instituto do Mar (IMar). Universidade Federal de São Paulo (UNIFESP). Campus Baixada Santista. Santos , SP, Brazil

Abstract

Coastal aquatic systems and oceans are under systematic and continuous inputs of hazardous residues, leading to loss of biodiversity. Among the most reported contaminants in environmental matrices obtained in coastal areas, plastic has gained great relevance since it is the main component of solid waste. Additionally, high environmental persistence and potential toxicity make plastics one of the most serious environmental issues of our time. Due to the impacts caused by the widespread use of these polymers, supposedly more sustainable alternatives have been developed and sold on the market, such as biodegradable plastics. However, recent studies have raised suspicions about the environmental safety of this kind of material, which in addition to generating toxicity, seem not to undergo degradation in real aquatic environments, within reasonable time scales. In addition, there are a large number of plastic utensils marketed under false claims of biodegradability (greenwashing), a phenomenon that has been the subject of recent scientific research. Therefore, it is likely that a significant portion of the plastic waste of the future will be made up of utensils that have been marketed under claims of biodegradability. In Brazil, few studies have been developed so far on this topic. This lack of information exacerbates our environmental vulnerabilities due to the lack of scientific information that can encourage the adoption of public policies adapted to the national reality. From this scenario, two fundamental issues emerged: (1) Are products composed of biodegradable plastics marketed in Brazil susceptible to degradation in real marine environments within reasonable time scales? and (2) do these materials induce environmental toxicity when reaching coastal systems? In this context, the present study aims to estimate the incidence of greenwashing in plastic utensils marketed in Brazil that are alleged to be biodegradable, and to assess the degradation rates and environmental toxicity of the polymers most frequently sold on marine organisms used as ecotoxicology models.