1. Title: Environment Risk Mitigation Measures for Anticoagulants used as Rodenticides. All PEC/PNEC for primary poisoning are greater than one;

Transcription

1 EUROPEAN COMMISSION DIRECTORATE-GENERAL ENVIRONMENT Directorate D - Water, Marine Environment & Chemicals ENV.D.3 Chemicals, Biocides and Nanomaterials ENV D.3/PB/PC/ENV RMM - 22/11/ Title: Environment Risk Mitigation Measures for Anticoagulants used as Rodenticides 2. Introduction: The outcome of the EU's Biocidal Product Directive review of all five second generation anticoagulant rodenticides (SGARs) (bromadiolone, difenacoum, brodifacoum, flocoumafen and difethialone) was that despite identified risks to humans, non-target animals and the environment, Annex I inclusion was granted because of their public health benefits and the lack of established alternatives which are both equally effective and less damaging to the environment. The final decision regarding how and where they could be used was delegated to Member States. It was agreed that: "Member States will be able to make restrictions at the product authorisation stage on the use of rodenticides containing any of the 2nd generation anticoagulants, which can go further than the risk mitigation measures explicitly set out in Annex I of Directive 98/8/EC. Such measures could include specific restrictions on outdoor use, or even a ban on such use, if such restrictions appear appropriate for sound scientific reasons." 3. Basic elements: On the basis of a comparative risk assessment for the environmental effects of SGARs (HSE, 2011) based on the risk assessments from the EU reviews (EU, 2011) and other data collected the following conclusions can be drawn: Data on the toxicity and persistence can be used to indicate that brodifacoum is the most toxic to birds and mammals, it is also the most persistent; difethialone and flocoumafen are more toxic than either bromadiolone or difenacoum; All PEC/PNEC for primary poisoning are greater than one; All PEC/PNEC for secondary poisoning are greater than one; As regards the secondary poisoning risk to birds, predator feeding studies indicate that depending on the feeding profile all SGARs can cause mortality and sub-lethal effects. These were not considered quantitatively in the EU reviews. Luttik et al (1999) reviewed several of the studies and stated that little can be deduced from these feeding studies about the relative toxicity of the compounds to barn owls, even when they are included in the same experiment ; Field trial data are available for flocoumafen and brodifacoum. Although limited, they do indicate that incidents can occur and were used to conclude that the use of these products Page 1 of 13

2 containing these active substances should be limited to indoor use only (ACP, 1987). No comparable data are available for either difethialone, bromadiolone or difenacoum; Data from a Predatory Bird Monitoring Scheme (UK PBMS) indicates that a wide range of species as well as a large proportion of predatory birds are exposed to SGARs. Although arising from rodenticide use the source of the residues is unknown, whilst their toxicological significance is not fully understood; Data from a Wildlife Incident Investigation Scheme (UK WIIS) indicates that incidents involving four out of the five SGARs do occur 1. The causes of the incidents range from correct use, unspecified, abuse or misuse. There is uncertainty regarding the exact cause of some of the incidents as it is not possible to identify the source of the rodenticide. There are also concerns regarding under-reporting (see Luttik et al (1999)); As described in the comparative environmental risk assessment (HSE, 2011), it is concluded that as the PEC/PNEC ratio is greater than 1 that no safe use can be identified on the basis of the available data for second generation anticoagulants. The PEC/PNEC ratio only provides an indication of whether the exposure can exceed the no effect concentration and should not be interpreted as indicating that all the active substances pose the same risk in terms of likelihood and frequency of impacts. In order to determine a ranking in terms of potential impact it would be necessary to have further data on the metabolism of the active substance, excretion rates, and binding strengths as well as ecological data on predatory/scavenging birds and mammals. Field trial data would also provide an excellent indication of whether the predicted risks are realised under field conditions. This information should be aimed at proving an indication of the likelihood and frequency of impacts. As the PEC/PNEC ratios are all greater than one, it is necessary to consider the role or impact of risk mitigation measures and in particular the likely impact they will have on reducing the risk. It should be accepted that in view of the need to control infestations of commensal rodents for public hygiene and economic reasons, and the importance of efficacious rodenticides in this policy, it is recognised that options might need to be considered which provide less than the maximum protection for non-target species and the environment, particularly where there are concerns for public health. 4. Aim of the Paper The aim of this paper is to discuss the range of environmental risk management measures available and determine what effect they have on reducing the risk. Finally, proposals are presented on potential ways forward for the EU, so that criteria for assigning risk mitigation measures can be agreed and applied consistently to SGARs at product authorisation. 5. Risk mitigation measures Risk mitigation measures are measures that reduce the risk to acceptable levels whilst still ensuring the product can be used appropriately. The EU Risk Mitigation Measures paper (EU, 2007) 2 outlines a range of possible risk mitigation measures and these are considered below. In considering the relevance of a risk mitigation measure, it is necessary to consider whether it will reduce the risk adequately and appropriately. In determining whether the use of a risk 1 No incidents have been reported for difethialone; as of June 2011 this anticoagulant has not yet been authorised for use in the UK. 2 ENV B.3/PC D(2007) - 21/03/ Risk Mitigation Measures for Anticoagulants used as Rodenticides Page 2 of 13

3 mitigation measure is appropriate and adequate it should be noted that for a use to be permitted, the PEC/PNEC ratio should be 1 or less. If it is greater than 1, then risk mitigation measures can be used to reduce the risk, either qualitatively or quantitatively, to 1, i.e. the ratio is in effect reset to 1. If this is not possible, then the decision to authorise a product and its associated use should be based on a risk benefit analysis. Outlined below is a consideration of a range of the risk mitigation measures along with an indication as to how, either qualitatively or quantitatively, they may reduce the risk Restrictions on methods of bait placement and composition Bait stations Regarding placement of baits, the EU Risk Mitigation paper proposed that "where appropriate, the product information could include an instruction that the product may only be used in bait boxes. However, it is also recognised that there are many satisfactory ways to prevent access to bait by non-target animals and the use of tamper-resistant bait boxes is but one of them. Effective rodent pest management is facilitated when tamper-resistant bait boxes are unnecessary, for example in locked buildings, with no public access and no access to nontarget animals, in wall and ceiling voids and in sewers. Also, the relatively high cost of these stations may deter users from placing adequate and enough baiting points, thus affecting treatment efficacy and duration." Comments: Data obtained under Predatory Bird Monitoring Schemes (UK PMBS) provides evidence that residues of SGARs transfer up the terrestrial food chain to non-target predatory/scavenging birds (notably barn owls, red kites and kestrels) and mammals. Residues in barn owls and kestrels in particular are thought to be due to predation on small live non-target mammals such as wood mice and voles, rather than predation on target rodents (rats or house mice). Therefore, protecting bait from non-target species such as wood mice and voles at the same time as reducing bait aversion for the target species could play a role in minimising the risk of secondary poisoning of predators and scavengers, as well as minimising the risk of primary poisoning. It is established that rats are neophobic and there is evidence that rats show aversion to consuming bait placed in manufactured plastic bait stations, compared with home-made bait stations (Buckle & Prescott, 2011; Quy 2010). The attractiveness of bait stations for rats depends mainly on the material and construction and the tamper-resistant bait stations must not necessarily be made of plastic. Wooden or metal bait stations are also commercially available and more attractive for rats than plastic stations, and even plastic bait boxes vary considerably in their attractiveness, depending on their design. It is recognized that plastic bait stations are less expensive and easier to carry than wooden or metal stations, but the advantages of the latter ones in terms of attractiveness clearly overweigh these drawbacks. In addition, there is no evidence that smaller mammals such as mice and voles (Brakes & Smith, 2005) show aversion to consuming bait in a manufactured bait station. Indeed bait boxes may provide a refuge for small mammals, and their use may inadvertently increase the secondary risk to predatory/scavenging birds as small mammals are a preferred food source for several of the species. Overall, although manufactured tamper-resistant bait boxes have an important role in preventing access of humans and other non-target species to bait, restricting all bait use to Page 3 of 13

4 them may prolong the time taken to establish control over a rat infestation and increase the risk of primary and secondary poisoning of non-target species. Therefore it is considered that users should be able to select from manufactured plastic bait stations, home-made bait boxes and covered bait points. The key issue is that bait should be placed in such a manner to ensure that non-target animals cannot gain access or access is restricted to a minimum. It should however be noted that this mitigation measure will potentially have some impact on secondary poisoning, i.e. if access to small rodents is prevented then birds that consume only small mammals (e.g. kestrels) will be reduced. The significance of bait boxes or bait placement in reducing the risk quantitatively is not known. The practicalities of restricting access to small rodents whilst still permitting larger rodents to access to bait is also not known Burrow baiting In a consultation the British Pest Control Association raised the issue of burrow baiting stating: "It is widely accepted that the best means of avoiding bait shyness and improving the efficacy of treatment is to deliver the rodenticide in a grain formulation directly to the burrow system of the rodent, providing all burrows are sealed after the treatment." Comments: In certain circumstances burrow baiting has been found to be an efficient method of bait placement, although the potential exists for bait to be spilled or pushed out of the burrow into the surrounding area, with the potential for primary poisoning (Quy, 2010). Therefore, where this technique is proposed on the product label, users will be required to revisit the site frequently to monitor and if necessary clean up bait should be considered Bait composition In the ESD (EU, 2003) there is reference to the role of bait composition. Grain baits probably pose a greater risk of primary poisoning compared to wax block formulations and therefore there is a potential increase in risk of primary and secondary poisoning. One way to reduce the risk is to ensure that only wax block formulations are used as wax blocks cannot be spilled like granular bait. However it is also known that wax block formulations are less attractive and thus less efficient than granular bait. Block bait is primarily used under wet or damp conditions or as permanent baits (see below). In situations where rodents are used to consuming granular food (which is very often the case), wax block baits have a clear disadvantage over granular bait in terms of efficacy. Another option is to limit the use of grain baits, pellets and liquids to indoor use only. 5.2 Restriction on user type The EU Risk Mitigation paper proposes: "It is also expected that professionals will be more likely to apply a number of risk mitigation measures (e.g. proper and secure placing of baits, recovery of unused baits, collection and proper disposal of dead rodents, etc) thus limiting the risk of primary and secondary poisoning. However, restricting the use of a given anticoagulant to professionals has also important drawbacks. It would in particular reduce the availability of these substances and consequently make amateur use more difficult, which may thus in turn hamper the fight against rodents, and mice in particular. In addition, if all current amateur uses of a given anticoagulant had in future to be only undertaken by professionals throughout the EU, the extensive infrastructure of professional pest management that such decision would make necessary does not yet exist." Page 4 of 13

5 Comments: In the some Member States professional users of biocidal products are currently defined as people who are required to use biocides as part of their work and who have received appropriate information, instruction and training. There is no requirement for formal accreditation. The use of bait by accredited professional users is expected to carry less risk of poisoning of non-target species than the use of bait by non-accredited professionals or nonprofessionals, but it is not possible to quantify the reduction in risk. In this sense, it is very important to follow the instructions of use and apply the Codes of Good Practices if available in rodent control of the rodenticidal baits thus, only professionals and specialised professionals are expected to apply and use the rodenticidal baits in a proper way. It should be noted that several field trials have been carried out (ACP, 1987) to assess the effects on non-target species from the outdoor use of brodifacoum and flocoumafen. Although these field trials were conducted under best practice, deaths of non-target animals both as a result of primary and secondary poisoning were recorded. Overall, professionals as currently defined above should continue to form the mainstay of rodent control, and that trade associations and other stakeholders have an important role in increasing the competence of non-accredited professional users. In terms of reducing the risk, it is acknowledged that by restricting use to professional users only should ensure that the risk is kept to a minimum; however, it should be acknowledged that the quantitative impact of restricting the use to professional users is unknown. Regarding non-professional (amateur) use of rodenticides, it should be considered that this may be increasingly important for the control of mice in domestic environments as local authorities increase charges for pest control services. Therefore, it is proposed to permit nonprofessionals (amateurs) to have access to products that can be used to control mice. It is important to take into account also that there are precautionary systems that can be implemented (prior to using chemicals to manage rodents) to deal with mice control (if the mice infestation is below 20). These precautionary systems such as; clean-up of areas of suspected rodent infestation and use of mice traps should be considered as the first steps in a rodent control process. In cases where the mice infestation is greater than 20 or the infestation is related to rats then the preferred option is to use professionals or specialised professionals. 5.3 Restrictions on permanent baiting Permanent baiting is currently carried out by pest controllers for two reasons 3 : Precautionary baiting of the perimeters of agricultural and food processing or storage premises with manufactured bait stations: In recent years this has become standard practice for the pest control industry and is often contractually required under commercial agreements between pest controllers and the food industry, due to food safety audit guidelines. For control of infestations subject to reinvasion information sources (Chartered Institute of Environmental Health, UK) has cited an instance of baiting for over 2 years to control a persistent rat infestation arising from a break in the sewer system, due to the failure of the local authority to repair the sewer. 3 UK consultation on human health risk mitigation measures Page 5 of 13

6 It is a condition of BPD Annex I inclusion that anticoagulant rodenticide products are labelled with the phrases "Unless under the supervision of a pest control operator or other competent person, do not use anticoagulant rodenticides as permanent baits. Remove all baits after treatment and dispose of them in accordance with local requirements". This Condition of Authorisation would therefore appear to allow permanent baiting with anticoagulant baits. Comments: Rodent control is a problem of integrated management (i.e. identification and elimination of the source of infestation). As a precautionary measure, permanent monitoring of rodent activities can be achieved using traps. Since control of traps can be labour-intensive, traps can be equipped with wireless sensors connected to a computer system, signalling traps which should be inspected. Systems with the same principle are bait stations with non-poisonous bait and movement detectors to observe and monitor rodent activity. These systems already exist and would most likely be accepted as means of prevention of rodent infestation according to food safety guidelines, especially in the food industry where the use of poison for pest control is usually considered as undesirable. We regard it as good practice that baiting should only start when rodent activity is observed. Permanent baiting of perimeter bait stations has been proposed as contributing to the presence of SGAR residues in non-target species, as small non-target mammals such as voles and wood mice are thought to readily enter bait stations to feed. Therefore, it is proposed to highlight the concerns of permanent baiting on product labels and indicate that permanent or long-term (> 6 months) baiting should only be permitted in extreme circumstances. It should be noted that the impact on exposure and hence residues in non-target mammals (or other non-target species) is unknown, however the proposed warning and restriction is unlikely to increase the risk. It is also necessary to consider that permanent baiting may increase the risk of development of resistances against rodenticides, since they pose a constant selective pressure for resistance and favours selection of rodenticide-resistant genotypes. 5.4 Frequency of revisiting bait points It is good practice for rodenticide users to visit bait points frequently in order to minimise the following: Primary risk frequent visits should ensure that any bait that is split or dragged out of bait boxes is removed Secondary risk frequent visits should ensure that dead and dying rodents are removed and hence not consumed by predatory/scavenging birds and mammals. Ensure appropriate efficacy frequent visits will ensure adequate bait and hence reduce the likelihood of target rodents consuming sub-lethal doses of bait It is a condition of Annex I inclusion that anticoagulant rodenticide products are labelled with the phrase "Search for and remove dead rodents at frequent intervals during treatment (unless used in sewers), at least as often as when baits are checked and/or replenished. Dispose of dead rodents in accordance with local requirements". However as "frequent intervals" is not defined, this could allow visits to be separated by relatively long time intervals, for example 4 to 6 weeks, and would potentially result in an increased risk to non-target species. Page 6 of 13

7 Comments: Received responses3 from the pest control industry raised concern that in practice pest controllers treating domestic infestations, particularly those working for local authorities, may be unable to gain access to clients properties at specified revisiting dates. It was, however, considered relatively likely that pest controllers treating commercial premises or farmers would be able to gain access to the bait points in this way. It is accepted that good site management is very important; however it is not known how this could affect the risk/impact, either qualitatively or quantitatively. In light of the above, it is proposed that the maximum time intervals between revisiting bait points should be specified for all anticoagulant baits as follows: The first follow up visit is to be no later than 7 days after the initial application of anticoagulant bait Subsequent follow up visits are to be no more than 14 days apart. Visits should be more frequent when required by the risk assessment (professional products only The above would be communicated via the label. There are potential concerns regarding the practicality and enforceability of this risk mitigation option, which would need to be resolved in consultation with the pest control industry. 5.5 Restrictions on area of use One risk mitigation measure proposed in the EU risk mitigation paper for consideration by Member States is restricting anticoagulant use to either in and around buildings or indoors, in order to reduce the risk of both secondary poisoning and primary poisoning. 'In and around buildings' is a term used in the ESD (EU, 2003) and is defined as: "the building itself, and the area around the building that needs to be treated in order to deal with the infestation of the building; this would cover use in sewer system, animal housing and ships but not use in waste dumps or open areas such as farmlands, parks or golf courses. Restricting the usage area is likely to have implications for rodent control and public hygiene, as well as on the risk of poisoning of non-target species. Indoor use can be defined as: Situations where the bait is placed within a building or other enclosed structure and where the target is living or feeding predominantly within that building or structure; and behind closed doors. If rodents living outside a building can move freely to where the bait is laid within the building, such as bait in open barns or buildings and tamper-resistant bait stations placed in open areas, this is not classified as indoors. However, sewers or closed drains are considered to be indoors situations. It may be necessary to have agreed/improved definitions of the terms "in and around buildings" and "indoors" to ensure risk mitigating management is effective, especially if nonprofessionals are allowed to use the biocidal product. Comments: It is clear that by restricting use to indoors only the risk of primary and secondary poisoning will be reduced significantly. It is appreciated that treated rodents will move from indoor Page 7 of 13

8 situations to outdoors, however this should be minimal. This restriction will obviously have large implications on the usefulness of the products involved. As regards in and around buildings it is acknowledged that this may reduce the risk to certain species of bird and non-target mammal. This is due to the fact that some predatory birds will not forage or hunt around buildings; however other species will forage in close proximity of buildings. Overall, the reduction in risk cannot be generally assumed. It should be noted that farm houses as one possible site for pest control in the scenario in and around buildings are hot spots for a great variety of herbivore and carnivore species which use surrounding buildings e.g. barns and stables as their habitat. In this context, it should also be taken into account, that non-target rodents like wood mice or field voles also feed on baits near e.g. farm houses (Brakes and Smith 2005) and therefore (i) are at risk for primary poisoning and (ii) pose a risk for secondary poisoning for predators and scavengers who do not live and hunt in the immediate vicinity of agricultural buildings. It should be considered consequently, if the same conditions as stipulated for open areas or waste dumps should be attached to the use situation in and around buildings. It should be noted that the risk assessments carried out as part of the EU review considered in and around buildings and all the resulting PEC/PNEC ratios were greater than 1. Furthermore, the exposure estimates in terms of residues in treated rodents as well as the amount consumed by predatory/scavenging birds and mammals is the same for in and around buildings as it is for use in open areas. There is further consideration of these issues below. 6. Proposed restrictions on areas of use As stated above, a risk mitigation measure is a measure that reduces the risk to acceptable levels whilst still ensuring the product can be used appropriately. On the basis of the evidence outlined above, the following are proposed: Use of appropriate bait boxes/bait stations/covered bait points/burrow-baiting to ensure that access to non-target animals is kept to a minimum Permanent baiting is restricted to only where it is essential Frequent site visits are required All the above could be implemented by appropriate label restrictions. However, there is a lack of evidence to indicate by how much the above risk mitigation measures will reduce the risk by. Or put another way there is a lack of information that the risk mitigation measure, or combination of measures, will effectively reset the PEC/PNEC to 1. The only one that will clearly result in an acceptable risk is restricting the use to indoors only. In selecting which proposal is appropriate, it is important to consider the need to control infestations of commensal rodents for public hygiene and economic reasons, and the importance of efficacious rodenticides in this policy. It is recognised that options might need to be considered which provide less than the maximum protection for non-target species and the environment, particularly where there are concerns for public health. In light of this as well as the above consideration, the following options are proposed: Proposal 1 - Restrict use of all SGARs to indoors only Available data indicate that all PEC/PNEC values are greater than one and hence unacceptable. Available field trial data for flocoumafen and brodifacoum indicate the potential for effects are realised in the field. No equivalent field data have been submitted for Page 8 of 13

9 the other active substances. Predatory bird studies are available for all five active substances and these indicate that mortality can result following exposure to all the active substances. Therefore, it could be argued that products containing either brodifacoum, flocoumafen, bromadiolone, difenacoum and difethialone should be restricted to indoor use only. This restriction could be overturned if additional data were available that indicates that the risk in practice is lower than predicted. It should be acknowledged that this proposal would seriously reduce the methods of rodent control outdoors. Therefore the impact of this proposal would need to be considered in detail to fully appreciate its wider implications. Alternative methods of rodent control and their limitations are summarised in Appendix 3. It is also possible to consider if certain formulations such as grain bait, pellets and liquid formulations should be restricted to indoor use because they pose greater risk to environment. This is because they can easily removed from the bait station or cover space. It should also be considered that the restriction of all SGAR to indoor use only may prevent effective rodent control in stables and open areas like parks and waste dumps and may remove the possibility to use effective measures needed to ensure public health and hygiene. Proposal 2 - Restrict use of all SGARs to in and around buildings This usage area is included in the ESD (EU, 2003) and the definition used for the risk assessment is presented in section 5.5. In light of the EU review and the resulting PEC/PNEC ratios this option cannot be supported, without additional ecotoxicological data. If this proposal was accepted as a restriction, a clear workable definition of "use in and around buildings" would be required that could be used by pest control operatives and other users. This definition would also have to be enforceable. As stated above it is not known whether this proposal will increase or decrease the overall risk in terms of likelihood and frequency of effects to predatory/scavenging birds and mammals. If this proposal is accepted then the following implications for non-target species and rodent control should be noted: 1. The use of products containing either brodifacoum or flocoumafen in and around buildings will overturn a precedent set in some Member States. This decision made by some Member States is based on a range of data (i.e. toxicity, persistence, predatory bird feeding studies as well as field studies) and concludes that use of these two active substances was unacceptable. It is considered that the risk from use of flocoumafen and brodifacoum will increase compared to the status quo. This is due to products containing these active substances being restricted to indoor use only. It is likely that the impact will be in line with the field studies conducted and previously considered. 2. As regards difethialone no field trial data are available and hence on the basis of the available data, it is proposed that the impact on non-target species will be in line with that observed for brodifacoum and flocoumafen. 3. There may be a slight reduction in the overall exposure from bromadiolone and difenacoum as products containing these active substances are currently approved for use in a variety of situations and hence restricting their use to in and around buildings may decrease Page 9 of 13

10 exposure. It should be noted that overall environmental impact from the use of bromadiolone and difenacoum in and around buildings is unknown. This proposal will remove the availability of products containing bromadiolone and difenacoum and their associated uses for certain situations, e.g. use in open areas. This will obviously impact upon those who currently use products containing these active substances. The implications of this would need to be assessed. 6. Resistance to difenacoum and bromadiolone has been recorded. It has been argued that outdoor use of flocoumafen and brodifacoum in these areas may pose a lower overall risk than the continued outdoor use of ineffective products containing either difenacoum or bromadiolone on rodent populations resistant to these substances. However, no data have been submitted to support this claim and therefore how this would affect the overall risk to predatory/scavenging birds and mammals is uncertain. It is not possible to predict the likely impact of this proposal in terms of likelihood or frequency of impacts. The overall risk from rodenticide use could increase significantly compared to the status quo and this could impact on key species but in certain circumstances rodent control may be needed. As this proposal will be a significant change to the status quo in some Member States and could result in putting key species of predatory bird and mammal at risk, it is considered that a more detailed consideration of this proposal would be required. The risk could be reduced by suitable risk mitigation measures e.g. the use of bait stations and the restriction on user type (professionals and specialised professionals). Proposal 3 - Maintain the status quo of certain Member States Currently in the certain Member States products containing brodifacoum, difethialone and flocoumafen are restricted to use indoors only. For flocoumafen and brodifacoum a range of studies including field studies provided data with sufficient information to determine that products containing these active substances posed a risk to birds and mammals. As for difethialone, no field trials were available; however a comparison of PEC/PNEC ratios as well as information on the toxicity, metabolism, and persistence indicated that it was not significantly different from either brodifacoum or flocoumafen. In this status quo, products containing bromadiolone and difenacoum can be used in a wide variety of situations both indoors and outdoors. The BPD reviews (EU, 2011) raised concerns regarding both the risk of primary and secondary poisoning from the use of products containing these active substances. No field data are able to confirm whether this risk is realised. It may be desirable, however, to maintain the status quo to ensure that appropriate rodent control measures are available. If this is accepted, then it is proposed that the uses of products containing SGARs are revisited in consultation with the rodenticide and pest control industry to determine how the products could be used whilst reducing and hence minimising the likely exposure to predatory/scavenging birds and mammals. It is proposed that the practicalities as well as the appropriateness and adequacy of the risk mitigation measures discussed above are considered fully to determine their likely impact on the risk. This could result in a range of further risk mitigation measures and/or restrictions to ensure that the risk is kept as low as practically possible. Page 10 of 13

11 Proposal 4 Professional Use Only Products containing difethialone, brodifacoum and flocoumafen should be authorised for indoor use only by professional users in all member states. Products containing bromadiolone and difenacoum should be authorised for indoor and outdoor use only by professional users in all member states. If a MS does not have trained and certified pest control operators then it should have the possibility to change the use category to private use in the frame of mutual recognition of authorisation. In this situation it is suggested that additional measures should be determined to ensure a proper and sustainable use of SGAR (e.g. prohibition of self-services by consumers, provision of adequate information by distributors selling rodenticides). In addition, more information on preventive and alternative methods to prevent and control rodent infestation should be provided. Determining success It is difficult to evaluate the practicalities, appropriateness and adequacy of the risk mitigation measures but these measures should be monitored. This monitoring may be performed by professionals and specialised professional. They are the most capable to carry out this task as they apply the Codes of Good Practices in rodent control, they will perform a control campaign when it is needed (an infestation greater than 20 individuals), verify if there is an increase or not of the dead non-target animals when they remove the dead rodents, as well as evaluate the susceptibility of the rodents to the active substance used. In addition, it is proposed that in order to determine the success of the above proposals certain schemes (e.g. Predatory Bird Monitoring Scheme (UK PBMS) and the Wildlife Incident Investigation Scheme (UK WIIS)) could be used. For example, if the chosen proposal did reduce exposure to predatory/scavenging birds then it could be detected by a decrease in the number of birds containing residues of difenacoum as well as the actual concentrations found. Page 11 of 13

12 References: ACP (1987) Advisory Committee on Pesticides Evaluation 1. Flocoumafen (available at Brakes CR & Smith RH (2005) Exposure of non-target small mammals to rodenticides: shorttem effects, recovery and implications for secondary poisoning. Journal of Applied Ecology 42: Buckle AP & Prescott CV (2011) Effects of tamper-resistant bait boxes on bait uptake by Norway rats (Rattus norvegicus Berk). International Journal of Pest Management 57, HSE (2011) Consideration of the environmental risk from the use of brodifacoum, flocoumafen, difethialone, difenacoum and bromadiolone. Health and Safety Executive (draft). Dawson A, Bankes J & Garthwaite D (2003) Pesticide usage Survey Report 175. Rodenticide use on farms in Great Britain growing arable crops 2000 (available at Dawson A & Garthwaite D (2004) Pesticide usage Survey Report 185. Rodenticide use by local authorities in Great Britain 2001 (available at EU (2007) Risk mitigation measures for anticoagulants used as rodenticides. European Commission Working Document ENV B.3/PC D (2007) (available at EU (2011) Assessment Reports for Inclusion of active substances in Annex I or IA to Directive 98/8/EC (available at Garthwaite D, De Ath A & Thomas MR (1999) Pesticide usage Survey Report 154. Rodenticide usage on farms in Great Britain growing grassland and fodder crops 1997 (available at EU (2003) Supplement to the methodology for risk evaluation of biocides. Emission Scenario Document for biocides used as rodenticides. EU (2007) Risk mitigation measures for anticoagulants used as rodenticides. European Commission Working Document ENV B.3/PC D (2007) (available at Luttik R, Clook MA, Taylor MR & Hart ADM (1999) The regulatory aspects of the ecotoxicological risk assessment of rodenticides. In Advances in Vertebrate Pest Management Pest Management, p , ed Cowan P.D. and Feare C.J. Filander Verlag, Further Germany. PBMS (2009) UK Predatory Bird Monitoring Scheme report (available at Page 12 of 13

13 Quy R (2010) Review of the use of bait boxes during operations to control Norway rats, Rattus norvegicus. Report to the Chartered Institute of Environmental Health. Page 13 of 13