Reversible toxicity in poisoning with colloidal bismuth subcitrate.

We thank the staff of the Aylesbury Vale breast screening service for their help and Drs E Rose and M Orton for allowing us to study patients under their care. 1 Working Party on Breast Cancer Screening. Report to the health ministers of England, Wales, Scotland and Northern Ireland. London: HMSO, 1987. (Forrest report.) 2 Tabar L, Fagerberg CJG, Gad A, et al. Reduction in mortality from breast cancer after mass screening with mammography. Lancet 1985;i:829-32. 3 Verbeek ALAM, Hendriks JNCL, Holland R, Mravunac M, Sturmans F, Day NE. Reduction in breast cancer mortality through mass screening with modern mammography. Lancet 1984;i: 1222-4. 4 United Kingdom Trial of the Early Detection of Breast Cancer Group. First results on mortality reduction in the UK trial of the early detection of breast cancer. Lancet 1988;ii:411-6. 5 Wilson A, Leeming A. Cervical cytology: a comparison of two call systems. BrMedJ 1987;295:181-2.