Earlier this month I was invited to the Microplastics Symposium to learn about the science and solutions around microplastic pollution in the San Francisco Bay Area. The symposium debuted a report that was the culmination of a three year joint study on microplastics in the bay conducted by the 5 Gyres Institute and the San Francisco Estuary Institute.

Before your eyes glaze over, let me tell you now, no matter where you live, this information is applicable to you. How? Because water connects us all, and there are lots of microplastics going into our water. So, hang tight and let’s dive in.

What is Microplastic again?

Microplastics are defined as plastics that are less than 5 mm in length. They can be broken off from plastic bottles. They can be microfibers that shed from clothing when washed or fragments that rub off tires. They can be tiny nurdles, which are pebble-size plastic pieces that are melted down to form plastic products.

What was the study?

The study took samples from all over the San Francisco Bay and then some samples from Tomales Bay as a reference. Tomales Bay is far from an urban population and does not have waste water that empties into it.

To select data collection locations, the study looked all the different ways microplastic could enter the San Francisco Bay–through wastewater, stormwater, and surface water.

While most studies look at microplastics in surface waters, this study also took sediment samples to see what sinks. Different plastics have different densities and thus will determine if they end up floating on the surface or sinking to the bay floor. If we’re only looking at the surface, we could be missing a large chunk of plastic pollution.

In addition, they sample different prey fish to see what microplastics they ingest. Prey fish are near the bottom of the food chain and are eaten by larger fish and animals, so understanding the plastics they ingest sheds light into the microplastics in larger animals.

Samples were also taken during dry and wet seasons to understand the variability rain adds to plastic pollution.

[Updated 1/15/20: Here’s a recently released video capturing the project.]

What was found in the bay?

17 billion microplastics enter the Bay from wastewater treatment plants and 7 TRILLION microplastic particles from stormwater each year.

I had a hard time imagining what 7 trillion particles would look like. If you stacked $100 bills onto pallets, to get to $1 trillion would look like this. At the bottom left-hand corner there’s a man as a size reference.

You can fit around 400 microplastic particles onto a dollar bill so this illustration gets you over halfway there. Looking at it this way you start to understand the scale of the problem.

Microfibers are the majority of microplastics from waste water.

As I mentioned in “11 Tips For an Eco-Friendly Wardrobe“, a single load of laundry can release up to 700,000 microfibers. So, it’s not surprising that samples collected from wastewater mainly show microfibers.

Stormwater has 300 times more microplastics than waste water. Nearly half are tire fragments.

The most surprising takeaway from the study for me, was that tire fragments make up nearly half of the microplastics from stormwater. It’s clear from the study that litter washed into our waterways is a big source of plastic pollution. But oftentimes we don’t think of tire wear as litter. And up until this symposium, it never even occurred to me that tires could be contributing to microplastic pollution.

The highest concentration of microparticles in the sediment were found in the South Bay.

The location of waste water treatment plants has a strong influence on this finding as there are a number of treatment plants that empty near the South Bay. As expected, concentrations of microplastics in the Tomales bay were the lowest found.

Tire fragments are dense and sink to the bottom of the bay before getting the change to be pulled out by tidal flow. The south bay has the highest concentration of tire fibers.

What are the solutions?

So, enough about the problem. We know there’s a big problem. But, I’m all about solutions. What can we do about all these microplastics going into our waterways? Here’s what the report suggested:

1. Reduce single-use plastics
2. Green stormwater infrastructure
3. Filtration
4. Textile industry innovation

Reduce Single-Use Plastics

No surprise here. The best way to stop microplastic pollution is to stop the source. While tires and microfibers got a lot of the attention in the report, there were polyethylene and polypropylene fragments in every sample. These are the two most common plastics used in single-use plastics.

As a reminder from “Why is Plastic Bad for the Ocean“, single-use plastics break down into smaller and smaller fragments. The fragments act as a sponge soaking up toxic chemicals and when ingested by fish, those chemicals are absorbed by the tissue of the fish.

Green Stormwater Infrastructure

Green stormwater infrastructure is essentially a filter for storm water. They are also commonly referred to as rain gardens. All the runoff from our streets would be filtered through this garden prior to entering the stormwater system on its way to our oceans.

Initial studies have shown that these gardens can reduce microplastic pollution by 90%!

Filtration

Like rain gardens, filtration focuses on catching the microplastic before it enters the ocean. Some ideas include:

• requiring commercial laundry facilities or laundromats to attach a microplastic filter to their washing machines.
• working with manufacturers to build in a microplastic filter into washing machines

Textile Industry

Microfibers are a big issue. Getting industry on board to better understand how the manufacturing of garments can affect their shedding characteristics is important. We need better materials and products from industry if we are to stop microfiber pollution.

What Can I Do?

1. Reduce single-use plastics
2. Choose natural fibers
3. Drive less
4. Talk to your representatives
5. Let brands know you want to see a change

Reduce Single-Use Plastics

By reading this blog, I hope you’re already making an effort to do this. If you haven’t started, try “Plastic-Free Basics” or “5 Tips for Plastic-Free Dining” and go from there.

Choose Natural Fibers

Like I talked about in “11 Tips For an Eco-Friendly Wardrobe“, choosing natural fibers is the best way to reduce plastic microfiber pollution. Synthetic materials like polyester and nylon are derived from oil and essentially plastic.

Drive Less

Note, I didn’t say stop driving. Unless that’s a feasible option for you. I know hardcore environmentalist expect you to walk and bike everywhere, go vegan, and stop flying, but I’m a realist. And I know that people need baby steps. (By the way, if you don’t drive or fly and are vegan…awesome job!) So, start by consolidating trips. The best way to do this is by planning ahead. If you know you need something at Target and a grocery store, can you stop by both in one trip instead of going to each on separate days?

Can you take public transportation? My mom was visiting us from San Diego and her company has a site in the Bay Area. Her boss offered to pay for an Uber so she could work face to face, but my mom opted to take the train and shuttle instead.

Can you bike to where you want to go? I recently read that biking to work made commuters happier…even when the commute was longer mileage-wise! Think about that. People who had to travel more miles where happier on a bike than people who had to travel less miles. If you think about it, it makes sense. You get to be outside, you don’t have to sit in traffic, and you’re making the Earth a little greener…win, win, win!

Talk to Your Representative

At the city, state, or federal level, you have the right as a constituent to let your elected leaders know that you want to see solutions. I spend a few days each year talking to my representatives in Sacramento (aka “lobbying”) about different plastic pollution bills. If your leaders don’t know that their constituents care about something, they won’t spend time working on it.

Start by Googling “find my representative” and the state you live in for state level representatives. If you want to start locally, find your city council members. Then you can either call, or send a letter saying that you want to see solutions for microplastic pollution. It only takes a few minutes to make your voice heard.

If you live in San Francisco, tell your county supervisor that you support the Reuse Ordinance that would help reduce single-use plastic usage in the city.

Let Brands Know You Want to See a Change

Social media is such a powerful tool. Small revolutions start with simple posts. We also have tools such as change.org to push for accountability. Use these tools to let the brands you love know that you want more natural fibers to select from in their clothing lines. Or that you want your favorite beverage to come in recycled glass. Or your products to come package free. Again, make sure your voice is heard.

So, like I said, no matter where you live, microplastic pollution affects you. The run off from your street goes into the ocean where a fish that you could be eating tomorrow (if you eat fish), can eat that tire fragment that just rubbed off your car. We are all connected by water. Thus, we need to find ways to stop microplastic pollution.

What do you think? Can you reduce your usage of single-use plastics? Or start choosing natural fibers? Maybe even call your representative? I think you can!

Still looking for more? Check out:

• 5 Ways to Reduce Microplastic Pollution
• Why “Green” Plastics Aren’t Any Better