Biodegradable Bioplastics: Their Pros and Cons from the Environmental Perspective

abstract

English

Biodegradable bioplastics (BBs) are developed and applied as greener and more sustainable alternatives to conventional plastics. Bioplastics production is based either on oil or biomass (bio-based), preferably biomass or organic waste and by-products. The most frequently used bioplastics include polylactic acid (PLA), polyalkanoates (PHB, PHBV…), modified starch, polybutylene succinate (PBS), polykaprolakton (PCL) or polybutylene adipate terephthalate (PBAT). Bioplastics are used mainly in packaging (ca 48 %, in total 1.07 million tonnes in 2022), but they are gradually used also in other applications including cosmetics, electronics, automotive, agriculture and textiles. Currently, their waste management technology includes almost exceptionally biological recycling, i.e. composting or biodegradation in soil whereas other recycling methods, e.g. chemical recycling, are applied rarely. Nevertheless, according to our results, the recommendation to use the BBs as greener alternatives of conventional plastics is not based on a though research data. The production price of most BBs is still higher comparing to conventional plastics, their processability is frequently problematic (melting and degradation temperatures are close, mechanical properties are sometimes worse comparing to conventional plastics, they need higher content of specific additives…), their biodegradation takes place only under specific conditions (temperature, number and type of organisms, moisture, pH, nutrients content) and their production carbon trace and influence on the environmental compartments and biota are largely unknown. Our team is focused on the effect of microplastics and microbioplastics on the environment. In this contribution we aim to advocate the view that the biodegradability of plastics should be a property of the product used during its lifetime but not at the end of life. We will present several examples that include a negative effect of poly-3-hydroxybutyrates particles and biodegradation on long-term soil organic carbon storage, soil desiccation, plant growth and aquatic plants stress and spreading the pathogens to illustrate this view.

bioplastics; microplastics; microbioplastics; polylactic acid; polyalkanoates; polybutylene succinate; polykaprolakton; polybutylene adipate terephthalate; waste management; biodegradation

Jiří Kučerík, Martin Brtnický, Jakub Fojt, Petra Procházková, Marek Trojan, Natálie Palucha

1. 11. 2023

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