Application for the Reassessment of a Hazardous Substance under ...

SECTION 7 – OVERALL EVALUATION7.1 Evaluation of options to reduce risk by restricting use7.1.1 In the absence of exposure information, ERMA New Zealand has used quantitativeexposure assessment models to determine the levels of risk to human health and theenvironment. This exposure modelling has produced indicative levels of risk that, inmany cases, are high.7.1.2 On the basis of this information, ERMA New Zealand‘s interim evaluation is thatthere are significant (non-negligible) risks associated with the use of dichlorvos inNew Zealand which outweigh the benefits and need to be managed. Most notably:risks posed to the aquatic environment;risks to birds;risks to non-target invertebrates;risks to operators;risks to bystanders.7.1.3 ERMA New Zealand notes that use of substances would be based on alternativeactive ingredients if the use of dichlorvos was restricted or prohibited:Potential alternatives have been identified for some agricultural uses ofdichlorvos and the hazards of these are shown in Table 14; many have a lowerhazard profile.For some crop/pest combinations no alternatives have been identified.Nevertheless, all the crops on which dichlorvos is used in New Zealand aregrown overseas in countries that do not use dichlorvos in plant protectionproducts.7.1.4 ERMA New Zealand also notes that there are particular benefits associated with theuse of dichlorvos, notably:dichlorvos has a different mode of action to other products that may be used ifits use is restricted or prevented. Maintaining a suite of products with differentmodes of action is an important means of reducing the likelihood ofdevelopment of pest resistance:dichlorvos possesses a unique combination of physical and chemical propertiesthat can provide rapid knock-down of pests, with short withholding periods,and can be used close to harvest, where other products might be precluded:dichlorvos used in the biosecurity fruit fly monitoring programme, which hassignificant economic significance, and for which no alternatives have beenidentified.7.1.5 ERMA New Zealand notes that the comparison of risks or benefits, for example arisk of chronic human toxic effects compared to a risk of aquatic toxic effects, andthe comparison of risks and benefits, for example an environmental or human healthrisk to a societal or economic benefit, requires value judgement. This is taken intoaccount in making recommendations (Section 6.1) and the Authority will take thisinto account in reaching an overall assessment of the risks and benefits.7.1.6 This evaluation takes into account that ERMA New Zealand‘s assessment is basedon the information that is available to it. Additional information is welcomed. ERMANew Zealand invites submitters to provide additional information that they mightDichlorvos reassessment – application Page 105 of 436