0
Article Tier 2 Human Health Effects Sign in to save

Toxicity comparison of polylactic acid and polyethylene microplastics co-exposed with methylmercury on Daphnia magna

Marine Pollution Bulletin 2024 7 citations

AI summary Read the abstract

Researchers compared the toxicity of biodegradable polylactic acid microplastics with conventional polyethylene microplastics, both alone and in combination with methylmercury, on water fleas. The biodegradable microplastics caused greater harm, significantly reducing survival and reproduction while also increasing mercury accumulation in the organisms. The findings challenge the assumption that biodegradable plastics are always safer for the environment, suggesting they may actually enhance the toxicity of co-occurring pollutants.

Models
Study Type In vivo

The prevalence of microplastics (MPs) in aquatic ecosystems has become a significant environmental concern due to their persistence and potential toxicity. Although bioplastics, such as polylactic acid (PLA), are promoted as eco-friendly alternatives to conventional plastics, their toxicity remains poorly understood. This study compares the toxicity and pollutant vector roles of polar PLA-derived bio-microplastics (bio-MPs) with apolar low-density polyethylene (LDPE) MPs, both individually and in combination with methylmercury (MeHg), in Daphnia magna. PLA bio-MPs, both alone and in combination with MeHg, significantly reduced survival rates and reproduction while inducing oxidative stress. Additionally, PLA bio-MPs increased Hg accumulation and negatively impacted acetylcholinesterase activity and vitellogenin gene expression compared to LDPE MPs. The findings of this study suggest that PLA bio-MPs, despite being in vivo biodegradable, may pose similar or even greater environmental risks than fossil fuel-based MPs, particularly due to their potential to enhance the bioaccumulation and toxicity of coexisting pollutants.

More Papers Like This

Article Tier 2

Chronic toxicity of biodegradable microplastic (Polylactic acid) to Daphnia magna: A comparison with polyethylene terephthalate

AI summary Read the abstract

Scientists compared the toxicity of biodegradable PLA microplastics with conventional PET microplastics on water fleas and found that PLA was actually more harmful. At higher concentrations, PLA microplastics killed nearly half the organisms, reduced reproduction, and increased birth defects more than PET particles did. This challenges the assumption that biodegradable plastics are safer for the environment, suggesting they may pose similar or even greater ecological risks than conventional plastics.

Article Tier 2

Ecotoxicity of polylactic acid microplastic fragments to Daphnia magna and the effect of ultraviolet weathering

AI summary Read the abstract

Scientists compared the toxicity of biodegradable PLA (polylactic acid) microplastics with conventional polyethylene microplastics on water fleas, a key species in aquatic food chains. The biodegradable PLA microplastics were actually more acutely toxic than conventional ones, partly because their higher density led to greater accumulation in the organisms. UV weathering further increased the toxicity of PLA microplastics, challenging the assumption that biodegradable plastics are automatically safer for the environment.

Article Tier 2

A comparison between the effects of polylactic acid and polystyrene microplastics on Daphnia magna

AI summary Read the abstract

This study compared the effects of polylactic acid (a biodegradable plastic) versus polystyrene microplastics on Daphnia magna water fleas, finding differences in toxicity that are important for understanding whether "biodegradable" plastics pose lower ecological risks than conventional plastics.

Article Tier 2

Aged biodegradable and non-biodegradable microplastics alter metolachlor toxicity in the gut and liver of crucian carp

AI summary Read the abstract

Researchers compared how aged microplastics from conventional polyethylene and biodegradable polylactic acid films interact with the pesticide metolachlor in crucian carp. They found that polyethylene microplastics increased pesticide accumulation in organs, while polylactic acid particles produced more complex and sometimes more severe toxic effects, likely due to their own degradation products. The study underscores that biodegradable agricultural films may not be inherently safer than conventional plastics when it comes to combined pesticide-microplastic toxicity in aquatic environments.

Article Tier 2

Multi-level toxicity assessment of polylactic acid (PLA) microplastics on the cladoceran Daphnia magna

AI summary Read the abstract

Researchers tested the toxicity of microplastics made from polylactic acid (PLA), a common bioplastic marketed as an eco-friendly alternative, on water fleas over 21 days. The PLA microplastics caused oxidative stress, depleted energy reserves, and reduced reproduction, though effects were generally milder than those reported for conventional plastics. This study challenges the assumption that bioplastics are harmless once they break down in the environment.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper