Milk A Protection Against Strontium

Press, Volume CII, Issue 30192, 25 July 1963, Page 12

Milk A Protection Against Strontium

Milk is one of the most valuable protective foods with respect to strontium-90. says the director of the Dominion X-ray and Radium Laboratory at Christchurch (Mr G. E Roth) in reply to a letter to the editor of “The Press” signed “Worried Parent ” Mr Roth says milk consumption reduces the amount of strontium-90 which could be laid down in newlyformed bones. The correspondent writes: "In Tuesday's issue figures were given which show that Greymouth, with an annual rainfall four times greater than Christchurch, has six times as much strontium 90 in milk, with the level at 18.9 picocuries per gram of milk-calc iun . There are many settled areas on toe West Coast where the rainfall is twice that of Greymouth. On the scale given above, these areas would have a level of 55 to 60. and there is nothing to say that toe level does not reach 100 or more. Would this constitute a safe level? Is there such a thing as a safe level? Should one drink milk so contaminated? Would it not be wise to take samples from an area where the rainfall is 200 inches per annum?” Mr Roto says: “The amount of milk coming from areas of highest rainfall (and thus fall-out) is small compared with the rest of the milk supplied to the country It therefore does not change the average strontium-90 intake of toe population, even if it were correct to assume with ‘Worried Parent’ that twice the rainfall produces three times as much stron-tium-90 in milk

"If people living in the highest rainfall areas consumed exclusively locallyproduced milk, their intake of strontium-90 would, of course be larger than that of the rest of the population The British Medical Research Council considers that even half of the permissible level would not be exceeded if the diet of an individual were

contaminated continuously with 400 strontium units "The latest available average yearly levels in milk (year ended April 30. 1963) is 6.1 strontium units for all of New Zealand, and 14.9 foi Greymouth, compared with for example. 56 3 and 66 9 respectively in the British counties of Merionethshire and Cumberland (year ended September 30, 1962). “Milk is, with respect to strontium-90. one of the mosi valuable protective foods It provides in our diet the

greatest amount of calcium for the human body. Thus by increasing the intake of calcium, milk consumption reduces the amount of stron-tium-90 which could be laid down in newly - formed bones,” Mr Roth says.