School Email Exchange

What is the minimum size plastic you can collect?  Are you missing the smallest particles?

Posted on November 09 2012

Question submitted by George Stevens Academy

The plankton nets we use to collect plastic have a mesh size of 333 um (~1/3 mm).  Marina Garland has been looking at even smaller microscopic plastics by filtering water samples.  The filter traps pieces larger than 0.5 um, and Marina then uses a dissecting microscope with 40X magnification to count them.  We also collect additional filtered samples for a lab in Seattle, WA, where new methods are being tested to detect even smaller pieces.

Bart DiFiore takes photos of biomass and plastic pieces in a sample under the microscope.