A federal government decision to allow the use of diuron on weeds will cause significant damage to the world heritage listed Great Barrier Reef, conservationists say.
The Australian Pesticides and Veterinary Medicine Association (APVMA) have lifted the suspended use of the diuron chemical, which was instated in 2011 pending a review of the chemical's effects when used in water bodies.
The new regulations were brought into play last Tuesday, restricting the spraying of individual crops.
However, no-spray times will not apply to sugarcane or pineapple crops.
"We have made a considerable effort to develop workable instructions for the continued use of diuron, while ensuring we can effectively manage risks from the use of this environmentally mobile and persistent chemical." APVMA spokeswoman Susan Whitbread said.
The chemical has not been regulated for use in industrial or non-agricultural applications as well as citrus, apples and pears, ornamental plants and tropical crops including tea, coffee and paw paw, The Australian reported.
In an attempt to further protect waterways, the guidelines stipulate farmers will not be able to spray when heavy rain is forecast.
World Wildlife Fund (WWF) spokesman Nick Heath said the decision would see freshwater systems contaminated, risking the health of marine environments and Australians.
Diuron is classified in the United States as a ‘known or likely carcinogen’.
"To give an indication of how toxic this stuff is, just one gram in four Olympic-sized swimming pools is enough to damage sea grass," Heath said.
Heath added that the chemical has been attributed to coral bleaching, sea-grass die-back and accounts for 80 per cent of herbicide pollution on the Great Barrier Reef.
Calling for government intervention, Heath said the chemical should be banned.
"The APVMA has again failed to protect the Great Barrier Reef," he said."We call on the minister and the prime minister to intervene and give the APVMA stronger powers and an obligation to ban these dangerous chemicals."
“The only way to ensure that Australians are safe from this harmful chemical and to keep it out of the marine and freshwater environments is to take it off the shelves completely. Alternative products are already available right now.” Heath concluded.
Supporting the restricted use of diuron, the Australian Cane Farmers Association (ACFA) has been angered by statements made by WWF freshwater manager Nick Heath.
ACFA chairman Don Murday said the restrictions would result in a crippling reduction in the use of the herbicide for Australian farmers, the Daily Mercury reported.