09/13/2013 05:44 EDT | Updated 09/13/2013 05:44 EDT

Like Seafood? You've Been Eating Your Own Garbage

Small pieces of plastic are capable of absorbing other forms of pollution in seawater. Mercury, PCBs, DDT and oily pollutants attach to plastic, so when animals consume plastic, the pollutants attached to them enter their bodies and move up the food chain, ultimately to the humans who eat seafood.

Plastics are among the most important substances used in modern human life. They are cheap, durable, lightweight and can be moulded into virtually any shape or size. But what made plastics so revolutionary is exactly what is now devastating the health of the oceans.

Plastics are made of several different compounds, almost none of which biodegrade. So when plastic enters a body of water, it will never go away. Sunlight and waves will only break plastic down into smaller and smaller pieces. These small, colourful pieces are attractive to animals who mistake it for food. To a seabird, a lighter looks like a fish, a small piece of plastic could be a fish egg, and a plastic bag could be a jellyfish -- a sea turtle's favourite snack.

These small pieces are also capable of absorbing other forms of pollution in seawater. Mercury, PCBs, DDT and oily pollutants attach to plastic, so when animals consume plastic, the pollutants attached to them enter their bodies and move up the food chain, and ultimately to humans who eat seafood.

Yes, we are eating our own trash.

The most startling example of the damage being done by our plastic addiction can be seen in the area of the Pacific Ocean infamously known as the Great Pacific Garbage Patch. My brother Tyler and I recently had the unique opportunity to join a sailing expedition with a team of scientists to the Pacific Garbage Patch to gather data on the abundance and distribution of plastics in the ocean and look for evidence of plastics interacting with marine wildlife.

The results of our survey were disturbing to say the least. While we expected to find plastic in higher concentrations in the middle of the gyre (the spinning ocean currents that collect floating debris into "garbage patches"), the concentrations of plastic outside the gyre were not much different than inside. It isn't just the gyres filling up with plastic, it's the entire ocean.

Even more discouraging is that, since many types of plastic sink, scientists have no idea how much is in the ocean -- they just know it is a lot. About 300 million tons of new plastic are created every year and less than 30 per cent will ever be recycled; much of the rest will either end up in landfills or flow into sewers, then rivers and lakes and out to sea.

The problem is truly global. While the North Pacific Garbage Patch has received the most attention, there are four other gyres or garbage patches spread across all oceans and each is continuing to grow in size. And new studies in bodies of water like the Great Lakes are revealing even higher concentrations of plastic in Lake Erie and Lake Ontario than are found in the centre of the most polluted gyres.

While the scientific community has been very effective at raising awareness about the problem, there is still a long way to go in solving it. There have been several ideas to build ships that could clean up the garbage patches, but after travelling there myself, I have no doubt that such a plan would be ineffective. Plastic in the ocean breaks down into such small pieces that no ship would be able to collect it all -- especially without harming an even greater amount of wildlife.

The only solution that makes any sense is to stop the flow of plastic into lakes and oceans in the first place. It is a daunting task, but the first step is to curb our addiction to single-use disposable plastic. So much of the plastic we use today is totally unnecessary and can be easily replaced by reusable items. Water bottles, coffee cups, straws, utensils... the list goes on and the solutions are simple. Biodegradable plastics that break down in seawater are already being invented, but are still several years away from becoming the norm.

If there is any good news about this problem, it is that every single person can have a positive impact by making simple changes in their daily lives. And if we don't, the plastic trash we continue to dump in the ocean will eventually end up in places you really don't want it... like your dinner plate.

Alex Mifflin and brother Tyler Mifflin host the award-winning eco-adventure series, The Water Brothers, exploring the world's most important water stories. The second season airs Tuesdays at 7:30 pm from September 10 - October 22 on TVO and at Learn more about plastic marine debris and its consequences in the episode, "Plastic Ocean," airing Sept. 17.

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