Petra Cameron and Philippa Kearney - Dumping Plastic into Ocean Poisons the Bacteria that Produce 10% of our Oxygen, underpin Marine Life
We’ve all seen the
impact of our plastic addiction. It’s hard to miss the devastating images of
whales and sea birds that have died with their stomachs full of solidified
fossil fuels. The recent discovery of a plastic bag in the Mariana
Trench, at over 10,000 metres below sea level, reminds us of the depth of
our problem. Now, the breadth is increasing too. New research suggests that
chemicals leaching from the bags and bottles that pepper our seas are harming
tiny marine organisms that are central to sustained human existence.
Once plastic waste is
out in the open, waves, wind and sunlight cause it to break down into smaller
pieces. This fragmentation process releases chemical additives, originally
added to imbue useful qualities such as rigidity, flexibility, resistance to
flames or bacteria, or a simple splash of colour. Research has shown that the
presence of these chemicals in fresh water and drinking water can have grave
effects, ranging from reduced reproduction rates and egg hatching in fish,
to hormone imbalances, reduced fertility or infertility, cardiovascular
diseases, diabetes and cancer in humans.
But very little
research has looked at how these additives might affect life in our oceans. To
find out, researchers at Macquarie University prepared seawater contaminated
with differing concentrations of chemicals leached from plastic bags and PVC, two of the
most common plastics in the world. They then measured how living in such water
affected the most abundant photosynthesising organism on Earth – Prochlorococcus.
As well as being a critical foundation of the oceanic food chain, they produce
10% of the world’s oxygen. The results indicate
that the scale and potential impacts of plastic pollution may be far greater
than most of us had imagined. They showed that
the chemical-contaminated seawater severely reduced the bacteria’s rate of
growth and oxygen production. In most cases, bacteria populations actually
declined. What can be done?.. read more:
https://www.juancole.com/2019/05/suffocating-ourselves-underpin.html
