From July's edition of The Green Guide:

As summer vacationers flock to the beaches to enjoy the sun, saltwater and sand between their toes, some disturbing facts linger: Each year an estimated 14 billion pounds of trash are dumped into the world's oceans. Plastics now make up 90 percent of all floating marine debris, and most of it originates from land.

Plastic bags, bottle caps, cigarette butts, food packaging and other waste ends up choking, poisoning or blocking the digestive tracts of sea birds, turtles and other marine animals who mistake it for food. Shrimp and fish ingest particle-sized plastic bits that resemble plankton. According to researchers at the Algalita Marine Research Foundation in Long Beach, California, there is some level of plastic in all of the seafood we eat.

Petroleum-based plastic contains suspected hormone-disrupting chemicals that leach out into substances it comes in contact with. It also absorbs toxics such as PCBs and pesticides, and can transport these chemicals via sea currents to shores where they are leached out again. And the problem isn't getting smaller: Algalita researchers are currently studying a "garbage patch" in the Pacific Ocean that is twice the size of Texas and growing by the minute.