Pesticide test proposal

Press, Volume CXIV, Issue 33448, 1 February 1974, Page 3

Pesticide test proposal

(.Veto Zealand Press Association)

NELSON, January 31.

A large American pesticide manufacturer is negotiating with the Cawthron Institute, in Nelson, to undertake its residual testing programme for many countries in the Southern Hemisphere.

The countries involved are some parts of SouthEast -Asia, the Pacific Islands, South Korea, Australia, and possibly South America and South Africa.

In each place the company's new pesticides will be sprayed on crops, and samples of the crops will be sent to the institute for an assessment of the amount of pesticide.

The manager of the chemical services section of the institute (Mr A. Cook) said the institute had been doing pesticide residual testing for three or four years for New Zealand manufacturers.

Before new pesticides could be released for use the Government required strict tests to show the residual effect on crops. This was very necessary because it had been found that some pesticides remained in the crops, and built up a residue in animals and humans.

To test pesticides crops were sprayed and samples taken daily for as much as a month.

These samples were then tested by the institute to find out how much of the pesticide remained on or in the crop.

For example, tests of apples the day after spraying might show that the residual amount of the pesticide was three or four parts a million. Three weeks later tests might show that the pesticide had disappeared. In such a case,

orchardists would be prohibited from selling apples to the public for three weeks after using the pesticide. “As a result of this work we have obviously had a lot of contact with the large overseas manufacturers. More recently we have been doing some work for a large American manufacturer on New Zealand samples. “Because its own laboratories are pushed to the limit we have been asked to handle samples from further afield. “The first job will be to work on 21 samples of tobacco from Thailand, and then we expect tomato samples from Fiji.” Mr Cook said that once a manufacturer formulated a new pesticide, a process which was inevitably tremendously expensive, it could cost as much as slm for an international testing programme to gain the necessary approvals to market it.