Breathing in iron sounds like a bad idea and yet millions of Chinese people are forced to do that. How does iron appear in the air? Industrial and vehicle pollution produce enough acidic gases to dissolve insoluble iron particles in East China’s major cities.
Scientists at the University of Birmingham say that these tiny now soluble iron-containing particles can cause respiratory illness as well as environmental problems.
The problem of industrial pollution is nothing new and yet it is still quite poorly understood. Breathing in that pollution is obviously not good for you because of toxic materials contained within it. However, that pollution can be acidic – so acidic, in fact, that it can dissolve iron out of larger ‘mixed’ pollution particles.
Scientists noticed that in Beijing, Handan, Zhengzhou and Hangzhou – all highly industrial huge cities – there is a lot of soluble iron in the atmosphere on haze days when atmospheric pollution from man-made sources is higher. They can be breathed in, causing adverse health effects though the generation of oxygen free radicals.
Where is that acidity coming from? Well, it is all man-made pollution. Those cities involved in this study are absolutely huge – Beijing has 21.5 million, Handan has 9.5 million, Zhengzhou has 10.1 million and Hangzhou has 9.8 million citizens. Pollution is coming from the industrial regions as well as traffic. For example, Handan is famous for its heavy industry, which consumes a lot of energy, which is mostly made using fossil fuels. Meanwhile Zhengzhou is a major road, rail and air transport hub. Out of all of these, the southern city of Hangzhou had the least amount of pollution.
But that’s not all. Those iron particles pose significant health risks for people, but they are also blown around quite a bit. The wind carries them to the Pacific Ocean, affecting the oceanic ecosystem. Iron is an essential external source for phytoplankton growth in large parts of remote oceans. And so this extra iron blown from industrial regions could be playing a significant positive role in the global carbon cycle and climate.
However, we don’t know what is the sum of all of this – the overall effect is more than likely to be negative on oceanic ecosystems and the climate overall. Especially because there are natural sources of iron already, such as desert dust and soil dust that is also carried by the wind to the ocean.
Scientists say that they need to research this phenomenon further to improve their understanding of those iron particles in the air. They want to see how oxygen free radicals are created and what kind of health risks exactly are they posing. But the message remains the same – reduction of air pollution should be a very important goal for Chinese policymakers as well as countries around the world.