Microplastics - when do they float, and when do they sink?

A lab demonstration showing why some microplastics float, and others sink. Fresh water and salt water have different densities. If the microplastic has a density less than the water, it will float; heavier it will sink. Interesting things start to happen when you have dense salt water on the bottom, and less dense salt water on the top. If the density of the microplastic is right, it will become suspended in the middle. Presented by Hans Peter Arp and Linn Merethe Brekke Olsen Norwegian Geotechnical Institute (NGI) Part of the JPI Oceans WEATHER-MIC project. http://www.jpi-oceans.eu/weather-mic/about