In February 2000 the NRA Expert Panel on Organophosphate Sheep Dips (OP) reviewed the findings of the UK Institute of Occupational Medicine (IOM) report, Epidemiological study of the relationship between exposure to organophosphate pesticides and indices of chronic peripheral neuropathy, and neuropsychological abnormalities in sheep farmers and dippers (July 1999). It concluded that work practices and exposure risks differed between Australia and the UK. However, the panel could not completely rule out a link between OP exposure and long-term effects on humans and the environment. The NRA expert panel recommended reducing worker exposure to OPs and that the APVMA review the uses of OPs on sheep.
There are a number of active constituents used as ectoparasiticides. Those considered by the APVMA during the review were alpha-cypermethrin, chlorfenvinphos, cypermethrin, cyromazine, deltamethrin, diazinon, dicyclanil, diflubenzuron, ivermectin, propetamphos, spinosad, temephos and triflumuron.
The review has focused on selected sheep ectoparasiticides for post-harvest wool and does not cover individual animal treatment products; nor does it include active constituents that are only approved for use on short wool (less than six weeks of wool growth).
The review does not consider occupational exposure during the application of ectoparasiticides.