A new study shows how long-term exposure to microplastics is creating breeding and growth problems for fish
Microplastics are a very serious environmental problem and more and more research shows the harmful effects of their presence on land but also in rivers, lakes and of course in the sea. A new study has now highlighted how long-term ingestion of these small particles damages fish growth and reproduction.
The amount of plastic waste (and microplastics in particular) in our oceans is constantly increasing. The persistence of microplastics in the aquatic environment, which can vary in size (from 1 µm to 5 mm) and in chemical composition, obviously has serious repercussions on marine ecosystems.
A new research, born from the collaboration between INRAE, Ifremer and the Universities of Bordeaux (France) and Orebrö (Sweden), aimed to study the effects of permanent exposure to microplastics on the key biological functions of fish.
In particular, two species of fish were sampled: the Danio zebra or zebrafish (Danio rerio) and the Medaka, (Oryzias melastigma), exposed for a period of four months to various microplastics.
The results, published in the Journal of Hazardous Materials, revealed harmful effects of microplastics on both growth and reproduction. The severity of the consequences on fish depended on several variables: the type of polymer, the presence or absence of organic pollutants and the duration of exposure.
As for microplastics, it was in particular about polyethylene (PE) and polyvinyl chloride (PVC), it was decided to evaluate the effects of these two as they are the most commonly present materials in packaging and plastic objects.
@Journal of Hazardous Materials
In fish exposed to microplastics, a decrease in growth, or more precisely in body size and weight, has been observed, regardless of the species or type of polymer. These effects were considerably greater after four months compared to two, which highlights how important it is to conduct long-term studies when evaluating the toxicity of microplastics.
Furthermore, this decrease in growth (between 20 and 45%) was observed mainly in females, possibly due to their higher energy needs during reproduction than that of males.
Reproductive rates have also been observed to decrease by up to 50% compared to normal ones. These interruptions varied according to the species of fish and the type of microplastic. For zebrafish, the combined exposure to PVC-BaP and PVC-BP3 led to delayed spawning and exposure to PE-BP3 and all PVCs led to a reduction in egg numbers.
In the medaka, exposure to almost all microplastics resulted in a reduction in the number of eggs produced by each female per day. Finally, PVC-BP3 caused behavioral disturbances in the larval offspring.
There is no doubt that the findings of this research show that exposure of fish to microplastics, for long periods, causes serious problems in the functioning of ecosystems. A problem that must certainly be investigated.
Follow us on Telegram | Instagram | Facebook | TikTok | Youtube
Fonte: Phys / Journal of Hazardous Materials
Read also:
- Fish have been ingesting microplastics for over 70 years, shocking new study
- One in five fish in the Adriatic Sea has ingested plastic
- Hundreds of species of fish, many eaten by humans, ingest plastic
- One in five fish in the Adriatic Sea has ingested plastic
- Microplastics are now everywhere: they are transported in the atmosphere from one continent to another
