Macarthur farmers are being urged to protect their stock against the risk of poisoning following the recent bushfire crisis.
Greater Sydney Local Land Services manager for biosecurity and emergency services, Graham Wilson, said there had been reports of livestock being poisoned as a result of ash in drinking water and exposure to burned infrastructure including treated timber.
"Stock water impacted by ash and debris is generally not a health risk for animals, however it can be if it becomes stagnant and/or is contaminated with dead animals or ash and residue from treated timber," Mr Wilson said.
"Wherever possible, ash and debris should be removed from dams, creeks and stock water troughs.
"Water sources can be protected from further contamination by installing temporary fencing to catch windblown debris or sediment."
Mr Wilson said Copper Chrome Arenate (CCA) treated timber and its resulting ash was extremely toxic and could be fatal to livestock if consumed.
"CCA-treated timber is commonly used in building construction, landscaping, decking, fence posts, orchard and vineyard trellising and other infrastructure," he said.
"Burnt stockpiles of CCA-treated timber pose the greatest risk to livestock.
"Livestock should be excluded from areas where stockpiles have been completely or partially burnt."
Mr Wilson urged anyone requiring advice or assistance to contact Greater Sydney Local Land Services on 1300 795 299.