asked Her Majesty's Government:

Further to the Answer by Lord Rooker on 28 April (Official Report, House of Lords, col. 1), why the Veterinary Products Committee recommended that they continue to license diazinon sheep dips when the Australian Pesticides and Veterinary Medicines Authority suspended authorisation for all sheep dips and jet sprays containing diazinon in May 2007 following evidence showing these practices may affect the occupational health and safety of rural workers. [HL3913]

The Australian Government's suspension of the diazinon sheep dip and spray products was based on the evidence reported in the second part of a preliminary review of diazinon, published in June 2006 by the Australian Pesticides and Veterinary Medicines Authority (APVMA).

The Veterinary Medicines Directorate (VMD) assessed the Australian preliminary report in relation to veterinary medicinal uses of diazinon. It concluded that the report contains nothing to suggest diazinon sheep dips should be banned in the UK. The Veterinary Products Committee (VPC) and the Medical and Scientific Panel (MSP) reviewed the APVMA documents and commented on the VMD report and its conclusions. Both independent committees agreed with the analysis provided by the VMD.

The primary reasons to conclude that the APVMA's review gave no reason to change UK government policy on OP sheep dips were:

acceptable daily intake (ADI) for diazinon—concern was raised that the authors of the report had added an additional uncertainty factor into both the internationally accepted ADI and their margin of exposure determinations and had based their conclusions on the reduced numbers. It was felt that the extra uncertainty factor was not justified and that the standard internationally agreed default values should have been used;

differences in personal protective equipment (PPE)—there are significant differences in the PPE required in Australia and the UK. In particular, PPE for the torso and legs differs significantly. In Australia, this consists of cotton overalls and water-resistant footwear/boots. The UK requirements are a boiler suit and bib-apron or waterproof coat, and waterproof trousers/leggings worn over Wellington boots. The report does not include sufficient detail to make an estimate of differences of total body exposure due to these differences in PPE;

extrapolation of experimental data—the Australian study was conducted by exposing workers to the various application methods by treating 50 sheep. This exposure was then extrapolated to a total of 2,000 sheep for dipping and 500 for jetting (assuming a linear relationship for exposure). This extrapolation in itself brings a degree of uncertainty into the final results;

application methods—the report gives no specific detail of the methods used to apply the diazinon in the study. Therefore, it is not clear if additional worker protection such as splash guards around dips and races were used as required in the UK; and

closed transfer system—one critical difference was that in 2000 in the UK the sheep dip packaging was redesigned to prevent operators being exposed to the concentrated product.

All of these comments were passed back to the AVPMA in response to its public consultation on its diazinon review.

The Government are and always will be guided by the best scientific advice. The MSP is tasked with the responsibility of continually looking at scientific papers worldwide and advising the VPC of appropriate action. The VPC has recently confirmed its advice that there is no reason currently to take any additional regulatory action on these products, provided they are used in accordance with the manufacturer's instructions.