We have to be aware that everything we throw into our toilet all goes to the sea.
For example, if we throw something plastic into our toilet and everyone who lives around the world does the sea, it is normal that afterwards it will contaminate.
Surely I have not been the only one but for example when you go to a beach or a cove I have found many plastic tabac masks ... yes.
I also met many people who later on the beach, well the cove that I go to in summer, there is a restaurant very very close by and there are many people who order ice cream for dessert and then the paper or whatever the ice cream takes throws it into the sea.

Conserve Water. Use less water so excess runoff and wastewater will not flow into the ocean.
Reduce Pollutants. Choose nontoxic chemicals and dispose of herbicides, pesticides, and cleaning products properly.
An estimated 50-80% of all life on earth is found under the ocean surface and the oceans contain 99% of the living space on the planet. Less than 10% of that space has been explored by humans. 85% of the area and 90% of the volume constitute the dark, cold environment we call the deep sea.
How many plastics are in the ocean?
There is now 5.25 trillion macro and micro pieces of plastic in our ocean & 46,000 pieces in every square mile of ocean, weighing up to 269,000 tonnes. Every day around 8 million pieces of plastic makes their way into our oceans.