Pesticide ban threatens world food security, expert warns
21 April 2011
The cost of some foods could also rise significantly because pesticides up to 10 times as expensive may be needed, says Ivan Kennedy, Professor in Agricultural and Environmental Chemistry in our Faculty. In a peer-reviewed paper published this week, he outlines extensive evidence that shows the substance, endosulfan, can continue to be used in carefully managed conditions.
Professor Kennedy acknowledges that in large doses endosulfan is a toxic substance. "Toxic chemicals necessary for efficient agricultural production will always be with us, but these should all be in constant review. There is evidence accepted by medical authorities that endosulfan has been handled safely in Australia."
Compared to DDT, which can persist in the environment for decades, Dr Kennedy explains endosulfan's short half life means that in most conditions it reduces to only negligible quantities in a few months, or even days on plants.
"Although it is not used in many fresh food crops in Australia, when it is used there is a withholding period, which means that by the time foods get to market minute traces of endosulfan above maximum residue levels (MRLS) are virtually non-existent," Professor Kennedy explains.
The worldwide listing and ban will be recommended next week by the Persistent Organic Pollutants Review Committee (POPRC) to the Stockholm Convention. There are 173 parties to the convention, including Australia.
"The lives of millions of people and the livelihoods of millions of farmers would be put at risk if a ban goes ahead," says Professor Kennedy.
"Some Australian horticultural industries, including macadamias, cashews and kiwi fruit, will struggle to survive under warm conditions with intense insect pressure without it. Experts in the cotton industry also consider it essential for integrated pest management." He warns that banning endosulfan could lead to greater environmental risks because the replacement chemicals may be more harmful. Less effective substances could also require more land to be devoted to farming.
"It is a case of the devil you know. There is more known about endosulfan than any other equivalent chemical. Although it is now banned in Europe, it is an important aid to farmers in sub-tropical zones, including many developing countries," he says.
"The POPRC has relied on cherry-picking the data, and testing in unrepresentative laboratory conditions, to classify endosulfan as a Persistent Organic Pollutant. Our recent review shows that POPRC has failed to establish that endosulfan meets their criteria as a POP. Taking such an extreme precautionary approach towards important tools for agriculture, as advocated by the green movement, places the global food security of billions of people at risk."
Instead of a global ban Professor Kennedy recommends a phase-out period of at least 10 years, to help the current main producers of endosulfan (20,000 tonnes annually), primarily in India and China, to adjust, and to give scientists and farmers time to research better alternatives.
Contact: Professor Ivan Kennedy