The piece by Carmel McHenry in the March issue (vol 9, no 12) makes some useful points, but I wonder if the issues are best aired by pillorying the Soil Association as being contaminated by commercial interests. A piece entitled "The selling (out) of organic meat" which then restricts itself to the curing of organic bacon, in which the Soil Association "concedes" that it has granted licences for some additives and "admits" it received some sponsorship from Sainsbury plc, may be sharp journalism but does it illuminate the area in which the discussion needs to take place?

The Soil Association's decisions on standards are not set in stone, are the subject of continuous debate and were the theme of a conference to be held in April/May this year. The Soil Association and Helen Browning both deny that there is any element of commercialism in their decision to permit a limited amount of sodium nitrite to be used in the curing of bacon and ham. Helen Browning's notes on Organic Standards make it clear that nothing is added to her organic meat.

When I first read the criticism that sodium nitrite was being used in organic bacon curing, I consulted a lecturer in inorganic chemistry at the University of Leicester who, while making no comment on the organic issue, confirmed the sound sense of the science underlying the decision.

Namely that, since using sodium nitrate (saltpetre) in the process produced variable (and, therefore, unpredictable) levels of sodium nitrite in the product, to use specific levels of sodium nitrite would give a control not otherwise available. This is purely a food safety issue.

We are all aware that there are dangers of botulism, salmonella and E-coli in food processing. We also know that certain substances are carcinogens.

The problems besetting the bacon curer seem to my unspecialised mind, to fall into the category of being damned if you do, and damned if you don't.

If the curer does not use sodium nitrate/sodium nitrite, he runs the risk of not eliminating botulism in the product; if the curer uses salt only, he runs the risk of not making bacon at all. Dr R S Dunning, Leicester......