Re: The treatment of cyanide poisoning.

(CWP) in the USA over the last 30 years. They then state, ‘Similar trends have been noted in Europe’. We would like to expand on this statement in respect of our experience here in the UK. In the UK coal mining industry, health surveillance (by chest X-ray) has been provided, over the last four decades, initially at 5 year, and since 1974, 4 year intervals. The prevalence of CWP among employed miners fell from 12% in 1959–1963, to 0.2% (13 cases, all ILO category 1) in 1994–1997 [2]. However, by 2000 it was apparent that an upturn in prevalence had occurred, and that there were some cases of category 2 or greater, including some in relatively young miners. An investigation by the Health and Safety Executive (HM Inspectorate of Mines) concluded that the upturn was probably attributable mainly to a recent tendency on the part of some miners to work considerable amounts of overtime, thereby increasing their exposure to dust. Contributory factors were thought to be an increase in development work (driving tunnels) in rocky strata and the introduction of more powerful mining machinery, both possibly leading to increased levels of dust production [3]. In conjunction with the occupational hygienist and a medical statistician, we have now completed a comparison of the prevalence of CWP with the available results of dust monitoring over the past 30 years. This reveals, semi-quantitatively, that the increase in prevalence is associated with an increase in average dust concentrations that began approximately 6 years earlier. (A report on this study has been made available to the UK coal mining industry and other interested parties.) The control of dust in the underground environment must remain a high priority for mining engineers, and health surveillance will be required within the industry for the foreseeable future.