Sarah-Jeanne ROYER
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I should have been in the ocean surfing, but my passion for finding a solution to the plastic-pollution issue had me in the lab. I was taking up where my colleagues had left off, and the reason that I'm here today is to explain to you my research over the last three years. Let's take it back from the start. Plastic showed up 70 years ago. It brought convenience to people. Plastic is very cheap, so it has a very low cost; it has durability, and it's very convenient. According to Times Magazine in 1955, plastic made people's life easier. They focus on the fact that disposable dishes and plastic would make the life of housewives much more convenient because they will spend less time washing the dishes, and gain time to go shopping. Overall, plastic had a big impact in different spheres of our everyday life, such as food, healthcare, transportation, plastic surgery and even clothing. Let's take a look at your clothes - or your neighbor's clothes if you feel comfortable. Look at the tag and realize that most of our clothes are made out of polyester, nylon and lycra. All these materials are plastic. And while doing yoga, you may only be covered in plastic. Namaste. Plastic has brought great convenience to people around the world and is used on an everyday basis. We all touch plastic today. But the short term convenience that it brings has a very long-term ecological cost. When you picture paradise, this is what you picture. This is Hawaii. But this is also Hawaii. This is also called away. When you take a plastic bottle and you throw it away, this is where it may end up. Hawaii is known for its plastic pollution. On our beaches, more than 95% of the plastic comes from outside of Hawaii. Mostly from Asia because of the geographical position of the Hawaiian islands. But overall, we are all responsible for this crisis because we all consume plastic. Out of 8,300 million metric tons of plastic produced to date since the 1950s, about 30% is currently being used, and a small share, that is recycled. Then about 10% of the plastic is incinerated. But 60% of all this plastic that's been made since the 1950s is currently in the environment and in landfills. This is an enormous problem, and we are far away from fixing it. Plastic production in the next 32 years is going to ramp up. The projections are that 12,000 million metric tons of this plastic will end up in our environment and landfills by 2050. This is double what we have accumulated in 70 years. At the University of Hawaii, at the "Center for Microbial Oceanography: Research and Education," we study the degradation of plastic. The finding of our research showed that the impact of plastic is even worse than what we thought. Let me share with you what we discovered. My colleagues Sara Ferron and Samual Wilson were making measurements of the biological production of methane in seawater, and the numbers they got were way higher than what they expected. They went back to their experimental protocol, and they realized that most of the methane was coming from nonbiological sources; it was coming from the bottles in which they were incubating seawater. The bottles were made out of a specific plastic: high density polyethylene, also named HDPE. HDPE will react because of the sunlight, will degrade and emit methane. Plastic emits methane; methane is a greenhouse gas. Methane makes up 20% of all greenhouse gases. Methane is 21 times more powerful than CO2. You take 21 molecule of CO2, and it corresponds to one molecule of methane. This is also one of the reasons why so many scientists are focusing on the the production of methane, from the permafrost to agricultural practices. So this unexpected discovery was the start of my two-year post doctorate at the University of Hawaii, where I focused mostly on the emissions of greenhouse gases from plastic in the environment. After this mind-blowing finding, we expanded our research. We selected the seven most commonly used types of plastic in the world. Low density polyethylene, LDPE, was the plastic type that will produce the most greenhouse gases. Some examples of LPDE are plastic bags, shampoo bottles, containers for food and vegetables. A lot of the LDPE products are single-use plastic: we buy it, we use it, and then we throw it away in a few minutes. Unfortunately, polyethylene, or LDPE, is also the most produced, consumed and discarded type of plastic in the environment. It also degrades quick, because of its weak chemical structure, and eventually contributes to the pool of micro plastic. As plastic degrades in the environment because of the sunlight, the plastic will start having cracks, bits, micro fractures, the surface area of the plastic will increase with time, and then, more greenhouse gases will be produced. Let's think about a bottle. The bottle of plastic that you bought at a shop produces very little greenhouse gases, but with time, the same bottle of plastic will degrade, the surface area will increase, and eventually, it will break down in small pieces, and with time, more and more gases will be produced. Let's put numbers here. For example, if we think of LDPE powder, and LDPE pellets - pellets are basically nurdles; they are virgin plastic used by the plastic industry to make other plastic items. For the LDPE powder, we will get 488 times more methane produced than for the pellets. This means then, as plastic degrades in the environment, all this plastic that we've been discarding is currently degrading, so more and more gases will be produced with time. As an oceanographer, most of my work is in the ocean. Most of the experiments we did were to look at plastic submerged in water. But as a comparison, we took plastic submerged in water, we compared it to plastic in air. This is when things got really scary. We basically saw that the plastic exposed to air will produce two times more methane than when it's submerged in water and 76 times more ethylene - which is another greenhouse gas - than when plastic is in water. This changed things. It means that not only the plastic in the ocean but the plastic all around us in the environment - in your back yard, your car, toys at the beach - are currently emitting greenhouse gases and contributing to climate change. Now we have to investigate more and see if it is a significant contribution. These results only further the need to find broader solutions to our overconsumption of plastic. I'm not here to vilify plastic; I'm here to understand the science behind the emissions of greenhouse gases from plastic. Of course, there are places around the world where plastic has saved life, but overall, the plastic we use is unnecessary and is only used as a convenience. Plastic is designed to last a long time, yet we still use it only for a few minutes. When we are done using plastic, it may end up in the environment, in Hawaii, and this for an undetermined period of time. It can easily last longer than your own lifetime or even your children's life. What to do next? I see this issue as a two-way approach. We have to think of the past, and we have to think of the future. So to deal with the past and all this plastic that's been produced, we have to find reactive solutions. But then, to deal with the future, we need to find a proactive solution to prevent the creation of the future plastic. For the past, we have all this plastic in the environment, and we only need to remove it, as simple as that. We can remove plastic through beach cleanups, ocean cleanup, drain river cleanup, even plogging, that I started in Barcelona in 2009, long before the word even existed. And also there is recycling and waste-to-energy. More effective than reactive solutions are proactive solutions and how to deal with the future plastic. We have to be proactive. This means dealing with the issue from where it's coming from rather than where it ends up, like Hawaii. It means finding better material, better technology and decrease the plastic production from the source. So imagine yourself after a long day at work, you go back home, you're about to take your keys, and then you see some water flowing from under your front door. You rush quickly into the house, you walk to the bathroom, and you see that the water is coming from there. You look and you see the bathtub overflowing. So at this point, you have two solutions. You either run out of the house, you take a bucket, you bail out the water from the bathtub; or you have the second solution, that is drastically much more efficient: you look at the source of the problem, and you turn off the tap. So next time you throw plastic away, think about a way to avoid it and think of Hawaii. Thank you. Merci. (Applause)