Deliverable 28: Specification of low risk products REBECA ...

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applicability of the proposed environmental risk indicator. Furthermore, advantages of the suggested risk indicator are compared to existing risk indicators used for conventional pesticides. Overview of current risk indices Numerous attempts have been made to compare the risks associated with different pesticides to one another. The complexity of these systems varies widely and ranges from a simple grouping of pesticides into toxicity classes, to more sophisticated measures, which use numerical data such as toxicity endpoints used for regulatory purposes. A thorough review of risk comparison systems currently used in different countries has been conducted elsewhere (Reus et al., 1999; Reus et al., 2002; OECD, 2004b; Mineau & Whiteside, 2005). Selected models are introduced here followed by a discussion of their merits and shortcomings in comparing the risks of microbials to those of conventional pesticides. Environmental Impact Quotient (EIQ) Among first risk indices developed for pesticides was the Environmental Impact Quotient (EIQ), which was published in 1992 (Kovach et al., 1992). The EIQ is used predominantly in North America, and classifications for new pesticides are regularly updated on Cornell University’s website (http://www.nysipm.cornell. edu/publications/eiq/). Essentially, the base EIQ for an active ingredient is the average risk calculated for the three sub-indices which describe the risk to (i) producers, (ii) consumers, and (iii) the environment. These sub-indices are calculated by using regulatory data such as dermal, oral and chronic toxicity to mammals (for consumer and producer risk), and toxicity to fish, birds, bees, other arthropods (for environmental risk). Various weighting coefficients, as well as soil and plant half life of the substance are also used as factors in the calculation. The "field EIQ" is derived by multiplying the base EIQ with the application rate and number of applications per year. While a good estimate to roughly assess the impact of pesticides, there are some major points of criticism that limit the usefulness of the EIQ. Firstly, the EIQ solely relies on the data established for the active ingredient. The type of application (e.g. soil incorporation, foliar spray), and formulation type are not taken into account. These are significant factors that will affect exposure to the pesticide and as such have a major influence on the risk, and hence the potential impact, resulting from a pesticide application. The EIQ should therefore be better described as a hazard quotient rather than a risk quotient. Secondly, the EIQ averages producer, consumer and environmental risks, which may result in a significant risk to one component being averaged out and overseen by a lower risk to others. For instance, a relatively high toxicity to fish or birds would not be appropriately accounted for if the risk to humans and mammals is low. Thirdly, weighting factors used on the EIQ are not explained or justified in the original publication and seem to be assigned arbitrarily. For instance, Mineau et al. (2005) noted that the environmental section of the EIQ is biased towards arthropods. With respect to the EIQ's application to microbials, there is often insufficient data available to feed into the EIQ equation, because of a higher likelihood of studies being waived in the registration process. Furthermore, the factors affecting the risks 15
esulting from microbial pest control products are not necessarily determined by the same variables as those for conventional chemical pesticides. Norwegian Indicator (NARI) The Norwegian Agricultural Inspection service has established separate pesticide risk indicators to assess human health and environmental risk with the purpose of tracking risk reduction over time. This was aimed to assist a government initiative, which had a declared goal of reducing pesticide risk by 25 % between 1998 and 2002, and also encompassed the introduction of risk based taxes on pest control products (Norwegian Agricultural Inspection Service, 2002). Compared to risk indices implemented in other OECD countries (OECD, 2004b), the Norwegian model is a step towards a more integrated model that attempts to include both exposure and toxicity. For the calculation of the Norwegian environmental risk indicator, scores are assigned for (i) terrestrial adverse effects, (ii) aquatic adverse effects, (iii) leaching potential, (iv) persistence, and (v) bioaccumulation. Scores in the terrestrial and aquatic categories are calculated using both toxicity of and exposure to a substance; values are assigned in two different groups of organisms (bees/earthworms/birds and fish/aquatic invertebrates/plants, respectively), the highest value in each category is used for the calculation. Values for persistence, mobility and bioaccumulation are also assigned according to set intervals. The environmental risk indicator is then calculated as the squared sum of all components. Modifications of the indicator are possible, defined for specific scenarios such as seed treatments or greenhouse applications. Microbial pest control agents are routinely assigned a value of one (lowest risk). The inclusion of exposure considerations, as well as the breakdown into separate environmental and health indices in the Norwegian model marks a significant advantage over the EIQ. Certainly, this allows for a more differentiated assessment of pesticide risks to humans and the environment. The advantage of the Norwegian system is that it is entirely based on data commonly requested by registration authorities, and as such data to calculate the risk score should be readily available, at least within governments. However, the Norwegian system also has some significant weaknesses. Most importantly, the indicator is simply a sum of its subcomponents, which is not reflective of interactions between the different components. For instance a high level of persistence, mobility or toxicity will each increase the risk posed to aquatic and terrestrial organisms. However, a very short half-life will significantly mitigate a high level of toxicity, whereas a highly persistent substance of the same toxicity will expose and possibly kill multiple times more non-target organisms. Another shortcoming of the Norwegian approach is the treatment of microbial pest control products. The simple flat-rate assignment of the minimal risk score to all microbial active ingredients may be a pragmatic approach useful in the context in which the Norwegian indicator is used but does not allow for a differentiated comparison between conventional chemicals and biological pesticides. For a regulatory comparative risk assessment or a farm level decision tool, a more sophisticated assessment of microbial pest control products is required. 16
Page 1 and 2: Deliverable 28: Specification of lo
Page 3 and 4: Table of contents Introduction.....
Page 5 and 6: Further more the substances which a
Page 7 and 8: Regulator’s experiences in defini
Page 9 and 10: Bacteria directly consumed by human
Page 11 and 12: Annex I. List of taxonomic units pr
Page 13 and 14: Annex 2 Developing a risk indicator
Page 15: cannot afford the high costs for a
Page 19 and 20: ERBIC Risk Indicator To our knowled
Page 21 and 22: The multiplication of non-target ri
Page 23 and 24: For a given chemical pesticide, the
Page 25 and 26: Indirect Effects. Indirect effects
Page 27 and 28: Table 7 Risk scores and calculated
Page 29 and 30: These results demonstrate that the
Page 31 and 32: Jaronski ST, Goettel MS & Lomer CJ
Page 33 and 34: Pest Management Regulatory Agency (

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