The far eastern Russian port of Nakhodka on the Sea of Japan is swathed in coal dust. It blankets the streets, clogs the air and is blamed by some for a rise in respiratory diseases among the city's 150,000 residents.

Yet despite pledges this year by Russia President Vladimir Putin to tackle coal pollution in ports such as Nakhodka and Murmansk thousands of kilometres away near Finland, port workers and local officials don't expect any change soon.

Once mainly an entry point for cars from Japan and an export route for Russian wood and fish, Nakhodka has switched in recent years to shipping almost nothing but coal from the vast mines in the Siberian region of Kemerovo, also known as Kuzbass.