OBAN – Microfibre pollution has been an issue in the deep sea for at least four decades, according to the findings of the first ever long-term study of the issue. Scientists studied the ingestion of microplastics by two deep-sea benthic invertebrates over four decades, going back to 1976. They identified eight polymers, of which polyamide and polyester dominated – indeed, 95 per cent of samples found came from textile fibres. Benthic invertebrates are organisms that live on the bottom of a water body (or in the sediment) and have no backbone. They include worms, clams, crabs, lobsters, sponges, and other tiny organisms.
The research found that ingested microplastic abundance in the study area remained relatively consistent from the period 1976–2015, although the data also indicates microplastics may have been present a the study location – Rockall Trough, North East Atlantic – prior to 1976.
Says the research paper: “Previous studies from marine systems have tended to provide only a snapshot in time and there is a lack of quantitative long-term data on microplastic pollution. This study provides one such assessment and indicates that microplastics may have been present on the seafloor at this locality prior to 1976.
“Specimens were collected between the years 1976–2015 from a repeat monitoring site >2000 m deep in the. Microplastics were identified at a relatively consistent level throughout and therefore may have been present at this locality prior to 1976.
“Considering the mass production of plastics began in the 1940s – 50s our data suggest the relatively rapid occurrence of microplastics within the deep sea. Of the individuals examined (n = 153), 45 per cent had ingested microplastics, of which fibres were most prevalent (95 per cent). A total of eight different polymer types were isolated; polyamide and polyester were found in the highest concentrations and in the majority of years, while low-density polystyrene was only identified in 2015.”
The study was jointly funded through the Scottish Association for Marine Science and the University of the Highlands and Islands.
Full paper: https://www.sciencedirect.com/science/article/pii/S0269749118330483