SYDNEY, June 21 (Xinhua) -- Australia's iconic Great Barrier Reef is littered with tiny broken down pieces of household items such as clothes, furniture and plastic, called marine microdebris, according to a study by Australian and Danish scientists released on Friday.
Researchers from the Australian Institute of Marine Science (AIMS) and the University of Copenhagen in Denmark took water and fish samples from the reef to find out the extent of microdebris contamination, a term which includes any man-made debris item smaller than 5 mm.
They discovered microdebris to be present in all 22 of their surface water samples, and in 57 of the 60 lemon damselfish they sampled.
Overall the micro debris the team collected consisted 86 percent of fibers, such as polyester and nylon fabric, and 14 percent of other microparticles, including plastic from bags, bottles and industrial packaging.
While it is not entirely clear how these contaminants reached the reef, study author Frederieke J. Kroon from AIMS told Xinhua that coastal river runoff could be the source on the inshore reefs -- however for the offshore reefs the source is less clear.
"The sources of microplastics on offshore reefs are currently unknown, but could include intentional and unintentional discard and waste water discharges from vessels on the reef, to long-range atmospheric and oceanic transport," Kroon said.
According to Kroon, microdebris is present in all marine environments where scientists have so far looked, the overall effect of which is not yet clear.
"Whether they are a threat to the global environment in general is not sure yet," he said.
"They are certainly found in many marine organisms, including our damselfish species -- whether that affects their condition, growth or survival we don't really know yet, and is research we are currently conducting."
