From plastic bags to pesticides - most of the waste we produce on land eventually reaches the oceans, either through deliberate dumping or from run-off through drains and rivers. This includes:

• oil
• fertilizers
• solid garbage
  
• sewage
• toxic chemicals
  

Plastic garbage, which decomposes very slowly, is often mistaken for food by marine animals. High concentrations of plastic material, particularly plastic bags, have been found blocking the breathing passages and stomachs of many marine species, including whales, dolphins, seals, puffins, and turtles. Plastic six-pack rings for drink bottles can also choke marine animals.

Several years ago a minke whale was found on a Scottish beach with 800kg of plastic bags in its stomach.

80% of urban sewage discharged into the Mediterranean Sea is untreated.