Magazine - UWA Pesticide Leaching Workshop

By Brendon Cant in Education on 28th Jul 2010 9:00

A better understanding of pesticides and the risks associated with their routine application to vegetation in Western Australian urban, natural and agricultural environments will improve the management of potential public health and environmental risks.

Able to migrate through air, sediment, groundwater and surface runoff, for example, the extent and ways in which pesticides leach through soil to non-target zones, such as lakes and rivers, was the focus of a recent University of Western Australia (UWA) workshop at its Institute of Agriculture on the Crawley campus.

Hosted by UWA’s School of Earth and Environment and School of Plant Biology, it discussed recent developments in pesticide fate, risk assessment and regulations.

After recently meeting with concerned representatives of local government and discussing pesticide management, UWA Associate Professor Barton and co-leader of the UWA Turf Research Program in the School of Plant Biology, approached UWA colleagues and specialists in the field, Professor Christoph Hinz and Dr Gavan McGrath, to present a workshop exploring current practices in pesticide management.

Dr McGrath said there was a need for a formalised, agreed risk assessment procedure, including an evidence based evaluation system and effective data collection, in order to manage the risks.

“Potential impacts such as contamination of our drinking water supply, dermal contact by children in parks and playgrounds, inhalation of spray drift and environmental effects, such as those on frogs in our surface water bodies, lakes and rivers, can’t be ignored.

“We need to create a culture where by sharing information we help create a solution and the full room today proves the clear need for better understanding of pesticide risk assessment,” Dr McGrath said.

According to Associate Professor Barton, a very real need for more science and greater evidence based information had been identified for those managing turfgrass in urban environments and about 50 consultants, state and local government representatives and turfgrass managers were therefore invited to participate in the UWA workshop.

“Attendees had a common interest in better understanding all aspects of pesticide leaching and what that meant for those applying the pesticides and for members of the public,” she said.

In discussing pesticide regulation in Australia and overseas, Dr McGrath said there was a need for funding to build a responsible pesticide management regime.

“Under Australia’s existing regulatory regime, responsibility for minimising risk to health and the environment is the responsibility of the user, who is most often the least informed on the possible risks to people and the environment,” he said.

“We’re not equipped in WA with a proper process in place to protect end users.”

Dr McGrath said progress on pesticide risk management in New Zealand and some parts of Europe offered a good example of the future direction needed for WA.

“The latest EU directive for 2011 includes safeguard zones for any surface and groundwater used for drinking water, prohibited use in specific areas used by the general public, residue limits for foods and training for pesticide users and salespeople,” he said.

Participants agreed there was a need for an easy-to-use risk management tool, developed in consultation with regulators, scientists and end-users, to assist WA turfgrass managers to better choose the type and timing of pesticide applications.

To demonstrate the need for tighter regulation, Professor Hinz discussed field experiments, risk modelling, atmospheric and rainfall components and how soil and water contribute to the off-site flow of pesticides.

“A key challenge is managing the multitude of pathways through which pesticides can migrate, including through air, sediment, groundwater, surface runoff and biological factors,” he said.

Town of Bassendean Director of Operational Services, Simon Stewert-Dawkins, said the UWA Pesticide Leaching Workshop provided a good opportunity to learn about recent developments in pesticide regulation in Australia.

“Our staff use chemicals in accordance with manufacturers’ instructions and the Town's Occupational Health and Safety Chemical Spraying Guidelines,” he said.

“Based on information presented at the workshop, I am keen for the pesticide industry to develop an easy-to-use, computer based risk assessment tool that could be applied to various WA soil types associated with turf and bush rehabilitation areas and for general horticultural crops.”

Callum Hitching of Sussex Turf Control, Dunsborough, said the workshop effectively communicated the need for better management of pesticides.

“These management tools are very important for the sustainability of our industry and its practices,” he said

“Where Sussex Turf Control staff are employed as total site managers, we will be incorporating these risk assessments into our services to give our clients the best possible outcomes.”

Compost WA Marketing and Development Officer, Doug Hall agreed, saying tools and methods such as adding organic material to poor soils, like many on the Swan coastal plain, could help ameliorate a number of issues turf growers and managers are grappling with, including water, fertiliser and potentially pesticide management.

“The WA compost industry is very keen to work with all industry groups, including the turf sector, to help build more sustainable management practices,” he said.

MEDIA REFERENCE:
Authorised by ‘The UWA Institute of Agriculture’ and issued on its behalf by
Brendon Cant & Associates (+61) 8 9384 1122
www.uwa.edu.au

Read more articles in Education, by Brendon Cant or from July 2010.