Slide I B U L T BIODEGRADE TO Some plastics are designed to break down naturally after use. But how long does this really take?

This experiment will help scientists to understand the biodegradation process in seawater from Bergen, Norway. Some plastics are designed to break down naturally after use. But how long does this really take?

This experiment will help scientists to understand the biodegradation process in seawater from Bergen, Norway — and allows you to watch it live.

Slide L Plastic Pollution P O L I T PLASTIC U O Plastic pollution is a worldwide problem, and it is still growing. Each year, more and more plastic ends up in the natural environment, raising concerns of risk to the environment, animal and human health.

But plastic is a useful material, and we depend on plastic products for a range of different applications. It is difficult to imagine that we could eliminate it from our lives. So what should we do?

First of all, we need to ensure that plastic waste is reduced, reused or recycled properly, so it doesn’t end up in the environment. We also need to improve how we collect waste, and reduce or eliminate littering.

But this is not always possible. So researchers all over the world are also working on new types of plastic that can be fully broken down by microorganisms. (Plastic items that only break down into smaller pieces like microplastics, or into smaller units that are not biodegradable, are not an improvement over conventional plastic.)

Could these biodegradable plastics be a solution for selected plastic products that accidentally or intentionally are released into the open environment? N

Slide The tank contains around 500 litres of seawater from the Bergen fjord, plus some fish that are typical to this area. The water is exchanged three times per day, and the temperature in the tank is about 11 - 12 degrees Celsius.

In mesh test containers, the scientists have placed small samples of:

• two different kinds of biodegradable plastics

• a conventional (non-biodegradable) plastic commonly used in plastic bags

• cellulose (the most common natural polymer on earth, and a typical component of plants as well as marine algae, which naturally biodegrades in the ocean)

Scientists will compare the biodegradation rate of the biodegradable polymers with that of conventional plastics, as well as the cellulose. WHAT’S IN THE TANK?

Slide E E N T ABOUT THE In this experiment, scientists are studying how long it takes for some kinds of biodegradable plastics to break down fully in a marine environment similar to the sea near Bergen, Norway. They are also studying which microbes are involved.

The scientists want to see how long the biodegradable plastic will last in cold sea waters, compared to previous experiments which were carried out in warmer Asian and temperate Mediterranean waters. The experiment will give insight into a realistic biodegradation time. X P E R I M

Slide ? E M A N FIND OUT MORE WHAT DOES BIODEGRADABLE REALLY The term ‘biodegradable’ does not mean that the plastic material will biodegrade anywhere, or in a reasonably short period of time. The rate at which a plastic item biodegrades is not just down to the material it is made of — it also depends on the conditions in the environment where it ends up.

Plastic that is designed to biodegrade in industrial composting facilities may not do so as effectively in the natural environment, whether in the soil, freshwater, or the sea. The rate at which plastic biodegrades in a specific ecosystem depends on a wide range of environmental conditions, including temperature and the presence of specific microorganisms. This is important because plastic items in the environment can cross from one ecosystem to another, and then its rate of biodegradation can change. The term ‘biodegradable’ does not mean that the plastic material will biodegrade anywhere, or in a reasonably short period of time. The rate at which a plastic item biodegrades is not just down to the material it is made of — it also depends on the conditions in the environment where it ends up.

Plastic that is designed to biodegrade in industrial composting facilities may not do so as effectively in the natural environment, whether in the soil, freshwater, or the sea. The rate at which plastic biodegrades in a specific ecosystem depends on a wide range of environmental conditions, including temperature and the presence of specific microorganisms. This is important because plastic items in the environment can cross from one ecosystem to another, and then its rate of biodegradation can change.