Return to Jim Sprott's Home Page

ARSENIC IN SHEEPSKINS A MAJOR CAUSE OF COT DEATH

by Dr Jim Sprott

At least 50% of all cot deaths in New Zealand occur when babies are sleeping on sheepskins. The Cot Death Association do not regard this as significant because 50% or more babies sleep on sheepskins anyway, but this ignores two basic questions:

  1. Why should any babies die on sheepskins?
  2. Why is the cot death rate in New Zealand still by far the worst in the world, now at least four times that in Britain?

There is compelling evidence that these two questions are closely related and that arsenic in sheepskins is involved.

The gaseous poisoning explanation for cot death is detailed in my recent book THE COT DEATH COVER-UP?. Essentially, very toxic nerve gases are generated by fungal action on compounds of phosphorus, arsenic and antimony in the mattress where the baby sleeps. The gases are, respectively, phosphine, arsine and stibine.

All the features of cot death are consistent with poisoning by an anticholinesterase agent, such as arsine (and the other gases mentioned).

Arsenic - Conversion to Arsine and Related Gases

The generation of arsine by fungal activity on compounds of arsenic was demonstrated conclusively by Gosio in 1892. This discovery explained the deaths of thousands of children in Europe from arsine generated in wallpaper, carpet and tapestry. Several other cases of poisoning from this cause have been reported.

New Zealand Sheepskins

Tests on New Zealand sheepskins (including new skins, used skins and skins on which babies had died of cot death) revealed that all samples tested contained significant amounts of arsenic. (They also contained phosphorus and antimony and were the only bedding products of about 70 samples tested which contained all three elements.)

There can be no doubt that the fungal generation of arsine (and/or closely related compounds) occurs in sheepskins used for bedding. Nor can there be any doubt that arsines are the cause of, and/or contribute to, many cot deaths.

New Zealand sheepskins sold for baby mattresses contain from 50 to 200 milligrams of arsenic per kilogram of sheepskin. The weight of a sheepskin intended for use in a baby's cot is about 1 kilogram, so that such a skin would contain 50 to 200 milligrams of arsenic.

The lethal dose of arsine for a baby has been assessed at less than 0.02 milligrams. Thus a sheepskin for baby use contains enough arsenic to generate between 2500 and 10,000 times the lethal dose of arsines. It is not suggested that all of this could be converted at once, but even if the generation of the gas were spread over 10 years one sheepskin could generate a lethal dose for a baby every day. Likewise not all the gas will reach the baby, but there is clearly sufficient gas potentially available to account for the deaths on sheepskins.

"Sanitising" sheepskins has no effect on the generation of arsine.

The more times a sheepskin is used, the better established becomes the fungus, and thus the greater is the quantity of gas generated.

While the toxic gas explanation of cot death has been attacked (wrongly) as regards phosphine and stibine, no-one can deny that arsine and/or its alkyl homologues can be generated from arsenic compounds in cot mattress materials (and other substrates) by the common fungus Scopulariopsis brevicaulis and certain related micro-organisms. Further, the extremely toxic nature of these gases is irrefutable.

Summary of Recent Experience in Britain

  1. The generation of arsines in Britain from sheepskins containing arsenic has been totally identified.
  2. The Turner Committee, set up by the British Government in 1990 to investigate the poisoning explanation for cot death, carried out tests which proved the generation of trimethylarsine by the fungus. This Committee recognised the danger of this gas and recommended that any additives to mattresses contain as little arsenic as possible.
  3. In the period up to 1994 there was a very high cot death rate among British Army personnel. When a family living on an Army service compound had a baby, a mattress was available from Army stores. The cot death rate among Army families was 4 to 5 times that of the equivalent civilian population. Army mattresses at the time contained an arsenical biocide (OBPA). When advised of this hazard, the Army withdrew the mattresses and replaced them with new ones free from arsenic. The cot death rate among Army families fell immediately and is now at a very low level.
  4. In 1995 Dr Callow and co-workers at the University of Birmingham demonstrated the generation of arsines by fungal action, with 100% success rate.
  5. In 1995 Dr Warnock and co-workers generated arsines on seven different occasions, but failed to do so consistently because their cultures were contaminated with sulphur, which precludes detection of the gases.

Conclusion

  1. The use of sheepskins as baby mattresses, if unprotected by a gas-impermeable sheeting such as polythene or rubber, should be discontinued forthwith. If this were done, we could confidently expect the cot death rate to fall by half, saving 50-60 lives per year.
  2. If parents wish to continue using sheepskins, these should be covered by wrapping in polythene (not PVC) or surgical rubber, firmly secured beneath the mattress with strong adhesive tape.
  3. This applies to every sheepskin on which a baby sleeps.

Note: If any parent is unsure of whether a particular plastic sheet is polythene, a free testing service is available. Mail a small sample of the plastic to T J Sprott, together with a self-addressed envelope.

Return to the Top

Copyright 1996 by T. James Sprott

Dr T. James (Jim) Sprott, OBE, Msc, PhD, FNZIC
Consulting Chemist, Forensic Scientist
10 Combes Road
Remuera, Auckland 5
New Zealand
Phone/fax: 64-9-523-1150
Email: sprott@iconz.co.nz

Reproduction and dissemination of this article is encouraged but written permission is required.