Statement On Blood Tests Challenged

Press, Volume CVI, Issue 31231, 1 December 1966, Page 1

Statement On Blood Tests Challenged

“Mr McAlpine’s statement on blood tests is so at variance with scientific findings that it could be ignored were it made by someone less responsible than the Minister of Transport,” Dr. P. B. Mating, senior police surgeon in Christchurch, said yesterday.

Mr McAlpine repeated on Monday a statement he made last week that blood tests alone could not prove that a driver was incapable of driving. The tests gave some indication of the degree of intoxication but were not sufficiently accurate.

It had been known for a long time that the consumption of the same amount of alcohol by different individuals would result in differing amounts of alcohol circulating in their bloodstreams, Dr. Mating said.

It would be amazing if it did otherwise considering that the individuals could differ in build, weight, age, physical fitness and dietary and drinking habits, to mention only a few of the variables, he said.

“The experiment quoted by Mr McAlpine and carried out on 10 persons in Wellington proves nothing other than the fact that at least one of the participants was rendered temporarily unfit to drive. “However this is not the point. The point is that it has been proved beyond doubt that anybody, and this includes the most hardened drinker, after consuming alcohol to raise his blood alcohol content to 100 milligrams per cent or over, is unfit to drive because his reflex actions are slowed.” The amount of drink necessary could vary widely. The amount of alcohol in the bloodstream was what mattered, he said. REACTION TIME

The visual motor reaction time —the tima taken between seeing something and taking action—was probably the most important factor in safe driving, Dr. Maling said. This visual motor reflex was one reflex which slowed in proportion to the amount of alcohol circulating in the bloodstream. “Mr McAlpine draws attention to the possibility of a driver being acquitted with

99 milligrams per of alcohol in his blood, but convicted with 101 milligrams per cent, and he considers this unreasonable. But is it?” Dr. Maling asked. One hundred milligrams was an arbitrary figure which experts considered to be fair, he said. In some Scandinavian countries the level was 50 milligrams per cent

The blood test was not used very often in New Zealand and the urine analysis and the nystagmus tests were generally favourable to the drinking driver. Many more drivers would be considered unfit to drive

if the blood tests were used more often he said. "Mr McAlpine is reported as saying that one who took part in his experiment had a blood alcohol content of 117 milligrams one hour after consuming only 7oz of whisky. Only 7oz of whisky is a little more than four double whiskies—more than enough to render most people unfit to drive if consumed in a relatively short time. “There is no doubt in the minds of those who have studied the problem of the drinking driver at first hand, that the most reliable criterion of a man's fitness to drive is his blood alcohol content. This applies to the time at which the sample is taken.” he said.

This was all that had been claimed for the test and remained as a simple basic finding however much the issue might be clouded by the Minister of Transport, Dr. Maling said.