Mikroskopiska plastpartiklar i havet: ursprung och effekter i marin miljö
Rapport, 2011
The issue of microscopic plastic particles was reported in Swedish media in 2008 after
records of high concentrations in the sea along the Swedish west coast. This study compiles
existing information about microscopic plastic particles in the oceans with the purpose to
investigate their extent, origin and observed and potential effects on marine organisms. The
results show that studies have been conducted since the 1970s, but that it still is an
inadequately studied environmental issue. Contemporary studies have shown a globally
widespread and increasing distribution of plastic particles in the oceans. Norén (2007) found
that the particles were much smaller and far more by number than indicated in previous
studies. The results further show a separation of plastic particles in two size intervals;
microscopic plastic particles (<0.5 mm) and plastic particles (0.5-5 mm). It was assumed in
several studies that plastic particles originate from larger plastic objects that have been
fragmented in the ocean. There were divided opinions whether particles less than 0.5 mm are
formed by fragmentation or not. No conclusion on the maritime industry’s share of the
microscopic particles in the ocean could be drawn, though two studies showed that
microscopic plastic fibers were greater in areas with high pleasure craft traffic. Furthermore,
three studies were presented that gave indications on the effects of plastic particles on marine
organisms. The first showed that plastic particles are eaten by sea cucumbers (Holothuroidea)
in a far greater extent than expected. The second showed that microscopic plastic particles are
accumulated and transported from the gut of blue mussels (Mytilus edulis) to their circulatory
system. The third study showed that organic pollutants can be transferred from plastic
particles to lugworm (Arenicola marina). It was concluded that microscopic plastic particles
in marine environments are uptaken by marine organisms, but that it is unclear whether it
results in adverse effects. The importance of further studies is emphasized, because the
smaller the plastic particles are, the risk of accumulation in the tissues of an organism
increases. It was further emphasized that policy-makers should focus on preventive measures.
effects
marin miljö
sources
microscopic plastic particles
ursprung
effekter
Mikroskopiska plastpartiklar
havet
mikroplast
marine environment