“… acceptable evidence to show that drift has occurred … is often difficult to establish. A perfect example was the alleged spraying of the Blackall Range Independent School with 2,4-D. Although a number of children became ill, no evidence of the chemical was found in tests taken against the person concerned. To establish that drift has occurred it is usually necessary to know what chemical is being used and to have the test done as quickly as possible. Even then as in the case mentioned, testing can prove a futile exercise and can be difficult and costly to organise. Surely the evidence of 20 affected children treated by a doctor should have been sufficent evidence for the State Government to take some action. p128 Quick Poison Slow Poison. Pesticide Risk in the Lucky Country. Kate Short 1994.