1. Chow, T. J., Chemy. Br., 9, 258–263 (1973).
2. Public safety: lead, Which?, 104–111 (Consumers' Association, London, April 1973).
3. Branquinho, C. L., thesis, Univ. Rio de Janeiro (1973).
4. Hunt, W. F., Pinkerton, C., McNulty, O., and Creason, J. P., in Trace Substances in Environmental Health, IV (edit. by Hemphill, D. D.) (Univ. Missouri Press, Columbia, 1971).
5. Schroeder, H. A., and Tipton, I. H., Archs envir. Hlth, 17, 965–978 (1968).