Plastics In Hong Kong Waters
In 2014, Hong Kong-based environmentalist and Maker-Bay Director Cesar Harada took a group of schoolchildren to a local lake to test a plastic sensor they had developed. But the test had to be abandoned almost immediately. “After a few seconds [we] had to stop the test because our experiment became the feast of many fishes and turtles. It was terrifying to see how how quickly plastic debris spread, how voraciously animals came to eat it and how difficult it was to clean it up. It took 10 of us, 4 boats and 40 minutes to clean 138 grams of plastic debris with no waves, no current and very moderate wind. Imagine tons of plastic debris in the open sea and all the animals there…”
Plastics contain toxins and take a very long time to disappear once they are introduced into the environment. Many plastic items are light and buoyant, and so disperse and spread rapidly in seas and rivers.Mistaking it for food, the plastic in the sea can be ingested by plankton, fish, turtles and seabirds. The fish may then be consumed by humans, who are then exposed to highly toxic carcinogens and chemicals released by the plastic when it reacts with acid in the stomach. Some of these toxins are classed as carcinogenic, meaning they can cause cancer, or lead to immune disorders and birth defects. For many animals like birds and sea creatures, ingesting plastic can block the digestive tracts, or they may also become entangled in discarded fishing lines and nets.
The ‘Great Garbage Patch’ is perhaps the most famous of the earth’s garbage ‘gyres’. It is located where ocean currents converge in the middle of the North Pacific Ocean. Other gyres are located in the Atlantic Ocean, Indian Ocean and the South Pacific. Researchers have studied global patterns and produced a chart which indicates that accretions of plastic may be more widespread than anyone expected. They say these garbage patches have “the potential to damage marine life and alter the biological environment.” Figure 1 illustrates the global distribution and density of the garbage gyres. The United State’s National Oceanic and Atmospheric Association (NOAA) has also produced an animation showing the ways in which garbage accumulates in the gyres which illustrates the way refuse accumulates in the gyres over time.