Types of Marine Debris
Plastics – As humans have developed new uses for plastics, the variety and quantity of plastic items in the ocean has increased significantly. Household plastic items frequently found in the ocean and along beaches include balloons, plastic bags, bottles and beach toys. Industrial plastic items found in the marine environment can include building materials, hard hats and lost or discarded fishing materials.
Plastics will degrade into smaller and smaller pieces until they are no longer visible; however most plastics do not completely mineralize or ever fully degrade into carbon dioxide, water or inorganic molecules. Even biodegradable plastics that can entirely break down in a landfill or compost system are not designed to break down quickly in the marine environment. Plastic debris accumulates PCBs (polychlorinated biphenyls) up to 100,000 to 1,000,000 times the levels naturally found in sea water. PCBs are known endocrine disruptors and research is being done on the potential transfer of chemicals throughout the food chain and the possibility of bioaccumulation in species, including humans.
Plastics consist of between 60% and 80% of total marine debris found in the Southern Hemisphere, (Gregory, 1997) 86% of all Marine Debris found in the North Pacific Ocean and between 60% and 70% in the Mediterranean Sea (Dahlberg 1985).
Glass, Metal and Rubber – These items are also used for a wide range of domestic and industrial products. While these substances can be broken down and worn away into smaller and smaller pieces, they do not biodegrade entirely in the marine environment. Common marine debris examples include glass bottles, aluminum cans and rubber tires.
Abandoned and Wrecked Vessels – Thousands of abandoned ships can be found in the waterways of our oceans and Great Lakes. These wrecks threaten navigation of other vessels and the environment. In protected harbors and bays, shipwrecks may be protected from excessive winds and weather which prevents them from breaking down quickly. In the open ocean, abandoned and wrecked vessels disintegrate much quicker causing debris from these accidents to be widespread and across numerous marine habitats.
Check out the rest of the Marine Debris section by following the links below to learn more about Marine Debris and GSTC patients that were affected by it!