Lancet, Vol.2 no.8102, 9 Dec. 1978, pg 1227-1230, Myeloneuropathy after prolonged exposure to nitrous oxide. --the B12 deficiency. Doesn't look like a real problem without very heavy use or very low B12 levels. Lancet, Aug12, 1978, pg339-342, Megaloblastic hemopoiesis in patients receiving nitrous oxide. --B12 metabolism Anaesthesiology, 1978, Dec67(6) 960-964, --sorry, havn't got the title, this is about teratogenic effects in rats. Anaesthesia, 34, 1979, pg147-151, --nitrous hazardous for patients with ear surgery or ear disease. Forgot to mention this problem in the previous post. Does not appear to be a problem if your ears are healthy. Seminars in Surgical Oncology, 1990, 6(3), 141-147 --cancer, cause or cure? Havn't read this one (not in the local library). Abuse of volatile substances, information paper 2, (Australian) Commonwealth Department of Health, Drugs of Dependency branch, 1984, --this is a great reference, a small booklet on N2O, patterns of abuse, obtainability, toxicity and side effects, etc. Probably difficult to get outside of Australia, but worth trying for. Acta Anae. Scand. 1985 29 pg 635-638, --study on volunteers looking at acute tolerance, subjective and objective observations. Review of inhalants: Euphoria to Dysfuntion, Sharp, C.W. and Brehm, M. L. (editors), NIDA research monograph no.15, U.S. Government Printing Office, October 1977 --this contains two articles, Abuse of Inhalation Anaesthetic drugs, by M.B. Chenoweth, and Preclinical Behavioural toxicology of Inhalant solvents, by R.E. Bowman, that are probably worthwhile. American Journal of Forensic Medical Pathology, 1988, Mar 9(1), pg 60-63, Death by nitrous oxide: an interesting case of auto-eroticism --sounds amusing. 1989, Dec 10(4), pg 330-331, --another suicide case