Causes of Pollution
What are the three main causes of ocean pollution?
Oil, chemicals, and plastic.
What is marine debris?
Man-made waste in the sea.
What is sewage?
Wastewater from homes and industries.
What is one major cause of ocean pollution?
Oil spills.
What industries create toxic chemicals?
Industrial and agricultural industries.
What did people once believe about the ocean and waste?
They thought the ocean was too big to be affected by waste.
What are two examples of marine debris?
Microplastics and old ships.
How does sewage enter the ocean?
Through sewers, rivers, or drainages.
Why are oil spills hard to clean up?
Crude oil lasts for years in the ocean.
How do toxic chemicals enter the ocean?
They are dumped directly or carried by rivers.
What agreement in 1975 helped protect the oceans?
The London Convention
How does marine debris harm marine animals?
Animals can eat it or get trapped in it.
What happens when chemical nutrients from sewage enter the ocean?
Oxygen levels drop, harming plants and marine life.
How do oil spills harm marine animals?
They can suffocate animals.
What is thermal pollution?
When chemicals raise ocean temperatures, harming marine life.
What did the London Protocol in 2006 ban?
Almost all waste dumping, except for some dredging materials.
Where does most marine debris come from?
Land, due to littering and bad waste management.
What is land run-off?
Water that flows over land into the ocean, carrying pollutants.
What is ocean mining?
Digging into the seabed to find minerals like silver and gold.
What happens to marine animals in areas with toxic chemicals?
They cannot survive and often die.
What is one way humans used to harm the oceans before regulations?
They dumped rubbish, sewage, and dangerous waste into the oceans.
What is one harmful type of marine debris from fishing?
Old or abandoned fishing gear.
What are "dead zones" in the ocean?
Areas with too little oxygen for marine life to survive.
How does ocean mining harm the ocean?
It damages deep ocean areas and increases toxicity
What is one example of a toxic chemical pollutant?
Pesticides, fertilisers, or industrial chemicals.