When I was a little boy I was impressed by and in awe of the doctor in Poplar who used to make house calls, as most doctors did then. He was tall and his name was Doctor Van Rossum. The good folk of Poplar treated Doctor Van Rossum like a saint, as he made his house calls however busy he was, and however poor we were, my father always took Dr Van Rossum a bottle of wine at Christmas, carefully wrapped in Christmas wrapping paper bought from Woolworths. Whenever I visited Dr Van Rossum he put his thermometer in my mouth, which he kept in a glass tube of pink liquid, having shaken the liquid off the thermometer and then shaken it some more.
Dr Van Rossum seemed to spend a lot of time shaking that thermometer.
His thermometer was filled with mercury, a metal which at normal earth temperatures is in a liquid state and expands and contracts, like all elements, according to the heat that it receives or it gives off. His thermometer measured my temperature which was part of the good doctor’s guesswork in establishing whether I should be given a medicine and if so what medicine. I now associate mercury thermometers with Dr Van Rossum and the comfort and security that his visits brought to me and my family.
Today mercury thermometers are banned, because mercury, which we used to push around on the desks in the chemistry lab at school, is a dangerous poisonous substance. If you eat it you will damage your digestive system and your kidneys; if you touch it you will damage your skin and your eyes, and if you breathe in its vapour you will damage your lungs and your kidneys. Mercury is too dangerous to be used in thermometers, it seems.
In fact it is so dangerous that the vast majority of nations in the world have just signed up to the Minimata Convention which sets out rules which if followed should reduce mercury pollution in the world. Mercury is frequently found in coal deposits and in the earth surrounding coal seams and when the coal is mined mercury is released into the atmosphere. Similarly mercury releases occur in small scale mining and sometimes in very large scale mining.
There is a mercury cycle which starts with the release of mercury into the air or soil, where it is spread into rivers and seas and then into animals including fish, which are eaten by other animals including people who when they die are buried or burnt. The cycle moves very slowly because mercury seems to hang around for long periods of time and in fish it stays with them their whole lives.
Today more than half the mercury emissions are created in South East Asia and it is quite right that there should be very strict controls on mercury emissions otherwise we shall poison our fish and damage our health. I have already written about mercury found in some sea food. It is a problem that is getting worse and that problem can only be solved in the long term by the nations of the world preventing the emissions of dangerous mercury into the environment.
However this dangerous poison, mercury, is now used in far greater and more fragile devices that the old mercury thermometers. It is found in low energy lighting, which today is in virtually every commercial building we visit and in the vast majority of homes. They are called compact fluorescent lamps and when electricity passes through the bulb the mercury heats up and reflects light in a way that enables the bulb to direct the electricity to use its energy on more light rather than on heat. If you break a compact fluorescent lamp you have to be careful, and open the windows and ventilate the room where you broke the bulb immediately and then leave for a while, because the mercury released from a broken compact fluorescent lamp in a small room could be very harmful to your health and is particularly harmful to the health of babies and the very young.
I suppose it is the way of the world that we now ban mercury in the thermometers like those that Dr Van Rossum used to use, but actually surround ourselves with gaseous mercury contained in fragile glass bulbs. Even more significantly we have been for years importing and using goods made in South East Asia with electrical energy created by coal burning power plants using coal mined in ways that are careless of the heavy mercury emissions into the environment they create. But then, the goods are cheap and that seems to be what matters most and the mercury emissions add to the work load of the good doctors in the world, like Doctor Van Rossum.
Filed under: climate change Tagged: | cfl, compact florescent lamps, Dr Van Rossum, environment, low energy lighting, mercury, mercury and health, mercury cycle, mercury emissions, mercury pollution., thermometers mercury