School Email Exchange

Are there different kinds of plastic?  If so, do you find all different kinds out at sea?

Posted on November 08 2012

Question submitted by George Washington Elementary School

If you check with your local recycling center you’ll find there are seven kinds of plastic:

#1 PET (polyethylene terephthalate) is used in many water, juice and soft drink bottles. This kind of plastic will sink (unless a cap on the bottle keeps air in it).  We are not finding #1 containers.

#2 HDPE (high density polyethylene) is used in milk jugs.  This type of plastic floats and we have found a lot of it.

#3 PVC (vinyl or polyvinyl chloride) used in cling wrap, children’s toys, shower curtains.
This type of plastic is often not recyclable and it doesn’t float.

#4 LDPE (low density polyethylene) found in most plastic shopping bags. LDPE also floats so we may be collecting this as well.

#5 PP (polypropylene) is used in baby bottles, plastic food containers and fishing line.  We have been finding lots of it in the gyre because it floats.

#6 PS (polystyrene, including Styrofoam) is used in takeout food containers and some plastic cutlery.  Foamed PS floats because of the embedded air pockets, but solid PS sinks.  Foamed PS is frequently sighted off the Seamans and brought aboard in tows and dip nets.

#7 Everything Else.  We have probably seen some #7 plastics but we are not able to identify them.

These are different types of floating plastic we found near a small boat.  Even the line is made of a type of plastic.

This large sheet of plastic must have recently dropped off a passing ship or it would have sunk.  Notice the tiny bits of plastic like confetti sticking to it.