How Long Does it Take Plastic to Break Down in the Ocean?

As hard as it may be to believe, modern plastic has only existed in our world for around 70 years. But in less than a lifetime, plastic has completely taken over nearly every aspect of our world, from our infrastructure systems to our daily lunch take-out.


While plastic has only been produced for a short amount of time, and takes very little time to produce each piece of plastic, its lifespan far exceeds that of nearly any other material on earth.


So how long does it take a piece of plastic to break down in our oceans? This question is complicated, because plastic doesn’t really biodegrade in the same way organic matter does. What it can do is break down into smaller and smaller bits until it is nearly undetectable.


Let’s look at some common plastic products and their lifespan once they enter our oceans.


Plastic Grocery Bags: 10-100 Years


Plastic grocery bags are made from thin sheets of high-density polyethylene (HDPE). When exposed to sunlight, these plastics can photodegrade in as little as 10 years. However, if they are hidden from sun or only getting partial sunlight, this process can take much longer, leaving millions of these plastic bags drifting through the oceans.


Plastic Drinking Straws: 100-500 Years


Plastic drinking straws are made from the thicker, more durable, but still flexible polypropylene (PP). Not only do these straws take longer to break down, they pose serious threats to marine life. Millions watched a viral video of a turtle with a straw stuck up its nose rescued by caring ecologists. Most animals are not so lucky.


Plastic Water Bottles: Appx. 450 years


Worldwide, over one million plastic water bottles are purchased every minute. Of these, only 20-30% are ever recycled, leaving the other 70-80% of plastic bottles produced scattered in landfills or other waste disposals, with many of them ending up in the ocean. The only way to dispose of plastic bottles, made of polyethylene terephthalate (PET) is to recycle them or burn them. Burning releases toxic chemicals and carbon emissions into the environment, contributing to global warming.


Monofilament Fishing Line: Appx. 600 years


Made of clear polyamide (PA) plastic, monofilament not only takes close to a century to photodegrade, it poses serious hazards to ocean life. Lost fishing line and abandoned plastic fishing nets regularly entangle animals from small fish to large, endangered whales, causing suffering and often death.


As we said before, none of these plastics truly disappear. They simply get broken up into smaller and smaller pieces that still float through our oceans, rivers, and streams, ending up in the bellies of fish and other marine life who mistake them for food.


The only way to get rid of plastic is to stop producing it. Companies like RIO are producing plastic-free, sustainable products that we can use in our everyday lives instead of cheap plastic products that will outlive us all.


You can read more about RIO’s mission to end ocean plastic pollution and how we are making products that promote a cleaner, more sustainable future for everyone.