From R ALLEN SALTAU
In the box in the article on the search for a safer process to decaffeinate
coffee, the author states that ‘the amounts of chemical solvents left in
beans .. are very small: less than 10 parts per billion (‘Anyone for designer
coffee?)’, 22/29 December).
This sounds small, but isn’t. Parts per billion equates to micrograms
per litre. Many chemicals have biological effects in small amounts. So the
presence of nanograms or even picograms of a biologically active chemical
may be significant, even more so if excretion is poor or body fat or liver
storage is involved.
R Allen Saltau Miles Australia
