Not above blunders

It is not only in the field of Pure Science that the problem of mistakes arises from time to time. Even within Applied Science and technology, mistakes are common. Often they are not wrongdoings as such, but mistakes that arise out of ignorance, oversight or lack of circumspection.

Take for example the drug chloramphenicol. At one time this drug was very widespread. It was a wonder drug, it seemed to cure everything. People were really sold on it, we all thought we were going to be free from illness ever after. Whenever you were sick, all you had to do was just go and buy some chloramphenicol, they sold it everywhere. Later on, after about ten years, it was discovered that this drug would gradually build up in the system, where it caused the bone marrow to cease production of blood corpuscles, and many had died of leukaemia.

Then there was the case of DDT. At that time it was thought that with DDT, our problems with the insect world were over – ants, mosquitoes ... all gone. We thought we could eradicate these creatures and no longer have to be bothered by them. Many years later it was found that DDT was carcinogenic, an insidious substance which could prove fatal even to humans. What's more, while the humans were suffering ill effects from the drug, the insect population was becoming immune to it. In time it became useless as an insecticide, and was more likely to kill the human beings. Many countries have banned the use of DDT, but Thailand is still using it, even now.

Then there was the case of thalidomide. Thalidomide was a pain killer and tranquilizer which was highly praised by the medical profession. It was reputed to have passed the most stringent tests, and was trusted so highly that it was announced as an exceptionally safe drug. It was so lauded that even the developed countries, which are normally very cautious about drugs and medicines, allowed the drug to be bought without a prescription. It was sold for about five years, up until 1961, at which time it was found that this drug, when taken by pregnant women, caused deformed babies. Before this danger was known and the drug was recalled from the market, about 8000 deformed children were born.

Let's take one more example, the case of CFC's (chloro-fluoro-carbons). This group of chemicals is widely used in refrigerators, air conditioners and in ‘pressure-pack' spray cans. These chemicals have been used for a long time with complete confidence. Before we knew what was going on, it turned out that these chemicals had risen up into the upper levels of the atmosphere and caused gaps in the ozone layer. A lot of it has already been damaged and scientists are very concerned; world conferences are being held to find ways to solve the problem. And so a new piece of knowledge arises – what we thought was a good thing turns out to be not so good after all.