9 OCTOBER 1971, Page 12

SCIENCE

Use of CS gas Bernard Dixon

It is all too easy to condemn totally the use of CS gas (and anything like it) at all times and in all circumstances. It is possible to argue, from either naivety or political motives, that the deployment of such chemicals in ' riot control ' is an abuse of civil liberties, an affront on the individual. It would be simple, therefore, to dismiss out of hand the final report, issued recently, of the Himsworth inquiry into the medical and toxicological aspects of CS, which concludes that the gas is safe for such use.

Let us instead deal with realities. There are occasions when crowds behave in an ugly, violent way, and when canisters of a harmless 'incapacitating agent are more sensible weapons to deploy than firearms. The argument should therefore be over whether or not CS is the harmless agent it is supposed to be. CS is, by definition, a vicious chemical with extremely unpleasant effects on the body. But is it safe to use on crowds of old and young, fit and ailing, who will inevitably be exposed; in all conceivable weather conditions and physical environments; on repeated occasions on the same victims?

These are the questions that should be answered fully, and in the affirmative, before an agent such as CS is made available to the police or military for use in controlling civil disturbances. They are much more stringent safeguards than would be required for a chemical agent used in more extreme but more restricted circumstances. In 1968, the UnderSecretary of State for Scotland said in a Parliamentary answer that in Britain such weapons as CS were to be used only against "armed criminals or violently insane persons in buildings from which they cannot be dislodged without danger of loss of life, or as a means of selfdefence in a desperate situation, and that in no circumstances should they be used to assist in the control of disturbances." The use of CS in August the following year in Londonderry was in flat contradiction of this statement, and it is against the background of this wider use that the report of the Himsworth inquiry, set up after the Battle of the Bogside, should now be judged.

As a scientist, there are many points in the report which disturb me (and which, were I living in Northern Ireland at this time, would doubtless worry me even more). I am not, for example, reassured to learn that "it is only under quite exceptional circumstances" that one could receive an excessive dose of CS, causing death. I am not reassured to be told that

the risk of serious eye damage caused by CS pellets lodging, in the eyes is small, or

that diarrhoea in babies following CS exposure is "of no practical importance." Whatever the instructions given to

troops, there is no doubt from eyewitness reports that CS has been used in Northern Ireland in far greater quantities than

envisaged by either the laboratory scientists who developed it or the authorities who sanctioned its use. It has, moreover, been deployed in an indiscriminate, punitive manner. However, because the symptoms produced are unpleasant, Himsforth explains, "even if the concentration is high the exposure dose received by mobile persons will be small." But what of the old and un-mobile, unable to escape when several canisters are lobbed into a doorway? The only experimental evidence about the effects of CS on the human body comes from work with service volunteers. They were fit, healthy young men, who received El per minute for being exposed to a strictly controlled concentration of CS under defined laboratory conditions. That is not the situation in Northern Ireland.

Nor am I happy about the negative deductions and lack of conclusive damning cited in the Himsworth report as grounds for sanctioning the use of CS. Inhalation of the gas can cause acute exacerbations of chronic bronchitis and asthma, says the report — and possibly of heart disease too, though the evidence on the last point is "inadequate," and such bouts of chest trouble would probably not differ in their course or severity from those due to natural causes.

Throughout the report, there is a feeling of Sir Harold Himsworth and his humane,

public-spirited colleagues poring over laboratory reports with such academic thoroughness that they tend to overlook the actual ' field ' conditions in which CS • is used. There was, as the British SocietY for Social Responsibility in Science has pointed out, no psychologist or specialist in social medicine on the committee. And some of the committee's recommendations for practical changes are naïve and impracticable. When a pellet grenade (s

bursting grenade) is used, for example, " there should be a warning to rioters t° keep their eyes closed."

The Himsworth committee has, however, performed one outstanding public service. It has recommended that when a chemical agent is released for civil use, the medical and scientific evidence relevant to this use should be published openly in scientific journals, and the Government has accepted the recommendation.