Micro-plastics represent one of today’s major problems in terms of water pollution. Its significance has become a global interest only in the last five years, whereby it needs to be noted that the studies to date have been done primarily in the developed western world (US, Europe). The IWRS was the first in Slovenia to begin conducting these types of studies and also established the methodology for sampling and sample analysis. The methodology is still being improved in cooperation with world-famous researchers in this field (the MSFD Technical Subgroup on Marine Litter).
Micro-plastics are plastic particles smaller than 5mm. Primary micro-plastics are small particles of plastics that are manufactured for use in the production of plastic products and in cosmetics. Secondary micro-plastics are derived from the breakdown of larger pieces of plastic. This type is mostly found in water. Micro-plastics are dangerous primarily because they are easily ingested by organisms due to their small size, thereby entering the food chain. Micro-plastics also release hormone disruptors and mutagenic chemicals into organisms.
http://www.unep.org/yearbook/microplastics.asp
http://www.adventurescience.org/microplastics.html