A Kg-pound mistake that was too costly
A $125-million Mars climate probe Orbitor was lost in 1999 due to a simple conversion error from metre to foot. This is well known.
But a bigger conversion mistake happened in 1953.
Dr Harold Hodge, a leading toxicologist, was entrusted with saying how much Fluoride is bad for human beings. Instead of 20mg/day being harmful for a 100 kg person, he reported 20mg/day being harmful for a 100 lb person.
How did this matter?
Well, Dr Hodge was helping the National Research Council of US to frame toxic limits for fluoride, and he happened to make this mistake of 2.1 which is the kg to lb conversion factor. This led to the standard of 1 mg/l of fluoride in drinking water.
Being an influential report, this carried on till the 1990s, until which many country standards had got formed based on this initial mistake that underestimated the toxicity of fluoride by more than 2 times.
High fluoride causes a problem of skeletal fluorosis to human beings. This can affect bones and cause deformities leading to crippling.
One space probe zoomed into the universe. One water standard mistake led to millions of disabled people. It is high time we recognize these mistakes, correct them and move forward.