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

is considered to be highly improbable. This combination of likelihood andmagnitude suggests a negligible to low risk. 54.4.3 ERMA New Zealand modelled likely exposure of people during use of dichlorvosfor the Use Scenarios for which appropriate modelling techniques exist. Details ofthe human exposure modelling are presented in Appendix G. These quantitativeestimates of exposure are related to concentrations calculated to cause effects toderive risk quotients. Given the complexity of the overall use pattern of dichlorvoscontainingsubstances, ERMA New Zealand has extracted the risk quotient data andprovided a summary plot as part of Appendix G to accompany the complete humanhealth exposure report.4.4.4 The conclusions of this risk assessment are:4.4.4.1 Operators:Although exposure to dichlorvos has potential to cause majorhealth effects, ERMA New Zealand considers that, given therequirements for packaging, transportation, storage, and the skilllevels of those persons involved in these stages of the lifecycles ofdichlorvos-containing products, ERMA New Zealand considers thatit is sufficiently unlikely that such adverse effects could occur.Additionally, ERMA New Zealand considers that it is highlyimprobable that even moderate adverse effects could occur.ERMA New Zealand has summarised and reviewed the riskquotients (RQs) calculated for the various Use Scenarios. Due tothe variety of Use Scenarios for dichlorvos-containingformulations, the Use Scenarios have been grouped, based on thecalculated RQ values. Certain Use Scenarios have been evaluatedwith a variety of operating conditions (e.g. using multiple 7Lcylinders vs. a single 35L cylinder), and due to those conditionsmay feature in several Risk Groups. In this event, only the lowestrisk group (and its associated conditions) for a particular UseScenario is identified. Also detailed in Table 10 are the conditionsupon which the Risk Quotient in question was determined.Where exposures have been determined to be negligible only whencertain conditions are adhered to, ERMA New Zealand considersthat those risks are non-negligible unless those conditions arespecified and implemented.5The ERMA New Zealand qualitative risk matrix based on evaluation of likelihood and magnitude of risk isgiven in Appendix J.Dichlorvos reassessment – application Page 45 of 436