Conclusion regarding the peer review of the pesticide risk assessment of the active substance fenpropidin

Fenpropidin is one of the 79 substances of the third stage Part A of the review programme covered by Commission Regulation (EC) No 1490/20021. This Regulation requires the European Food Safety Authority (EFSA) to organise a peer review of the initial evaluation, i.e. the draft assessment report (DAR), provided by the designated rapporteur Member State and to provide within one year a conclusion on the risk assessment to the EU-Commission. Sweden being the designated rapporteur Member State submitted the DAR on fenpropidin in accordance with the provisions of Article 10(1) of the Regulation (EC) No 1490/2002, which was received by the EFSA on 24 June 2005. The peer review was initiated on 23 March 2006 by dispatching the DAR for consultation of the Member States and the sole applicant Syngenta Ltd. Subsequently, the comments received on the DAR were examined by the rapporteur Member State and the need for additional data was agreed on during a written procedure in January - February 2007. Remaining issues as well as further data made available by the notifier upon request were evaluated in a series of scientific meetings with Member State experts in May - June 2007. A final discussion of the outcome of the consultation of experts took place with representatives from the Member States on 14 November 2007 leading to the conclusions as laid down in this report. The conclusion was reached on the basis of the evaluation of the representative uses as a fungicide on cereals full details of the gap can be found in the attached end points. The representative formulated product for the evaluation was "Tern 750 EC", an emulsifiable concentrate formulation (EC). Fenpropidin is a racemic mixture. It has been identified that more information is necessary to enable the impact of potential different isomer ratios on the risk assessments to be better characterised. Adequate methods are available to monitor fenpropidin (and its salts expressed as fenpropidin) in products of plant origin, soil water and air and fenpropidin (and its salts expressed as fenpropidin) and CGA 2892672 in products of animal origin. Only single methods for the determination of residues are available since a multi-residue-method like the German S19 or the Dutch MM1 is not applicable due to the nature of the residues. Sufficient analytical methods as well as methods and data relating to physical, chemical and technical properties are available to ensure that quality control measurements of the plant protection product are possible. There is an outstanding data requirement for a sprayability study to address the poor emulsion stability of the formulation. In mammalian toxicity testing, fenpropidin is acutely toxic via ingestion and inhalation (LD50 1452 mg/kg bw and LC50 1.22 mg/L). It is not acutely toxic via dermal route. It is irritant to skin and eyes but not corrosive. It is a skin sensitiser in both the Buehler and Maximization tests. Classification with Xn R20/22 (harmful by inhalation and if swallowed), Xi R38 (irritating to skin), R41 (risk of serious damage to eyes) and R43 (may cause sensitisation by skin contact) is proposed. According to a 28-day inhalation study showing irritating effects to the respiratory system, classification of fenpropidin as R37 ("irritating to the respiratory system") is warranted. The relevant NOAEL for short term toxicity in rats is 1.14 mg/kg bw/day, whereas in dogs is 2 mg/kg bw/day, based irritative effects and liver effects, respectively. Fenpropidin does not show any potential for genotoxicity, carcinogenicity, reproductive and potential toxicity. The relevant long term NOAEL is 2.27 mg/kg bw/day based on decreased body weight; maternal and offspring NOAELs are 8 and 18 mg/kg bw/day, respectively, whereas the reproductive NOAEL is 9 mg/kg bw/day. The relevant maternal and developmental NOAELs are 90 and 12 mg/kg bw/day in rats and rabbits, respectively. Fenpropidin showed a neurotoxic potential in the repeated dose studies, expressed as spinal chord demyelination at the maximum doses tested in a 90-day rat and 1-year dog study. The NOAELs were 5 mg/kg bw/day in dogs and 10.1 mg/kg bw/day in rats. The ADI, AOEL and ARfD are 0.02 mg/kg bw/day (SF 100). The operator exposure of fenpropidin in field crop scenario with a tractor mounted hydraulic boom sprayer shows exposure levels below the AOEL when appropriate PPE is worn (gloves during mixing/loading and sturdy footwear and coveralls during application). Workers and bystanders show exposure levels below the AOEL under worst case assessments (67% with PPE and 4.5%, respectively). The metabolic pathway of fenpropidin in cereals has been elucidated. Several routes of metabolism have been identified but the metabolic pattern in wheat grain and straw at plant maturity is clearly dominated by the parent compound. Therefore the residue definition for risk assessment and monitoring in cereals is restricted to fenpropidin. Supervised residue trials conducted in Northern Europe support the setting of MRLs of 0.1 mg/kg in wheat, rye and triticale and of 0.3 mg/kg in barley and oats. High residue levels were found in straw. Under processing the nature of fenpropidin residues is not affected and residues are preferentially transferred to bran during the milling process. The transfer factor from barley to beer could not be determined exactly but is below 0.4. A transfer of soil residues to rotational crops after cereal use is not expected. A significant exposure of livestock mainly resulting from consumption of straw is expected. Animal metabolism studies in lactating goats and laying hens show that fenpropidin is extensively metabolised in livestock and a complex residue pattern is found in edible tissues. The residue definition for monitoring animal commodities consists in the sum of fenpropidin and one of its major animal metabolites (CGA 289267). For risk assessment, further major metabolites need to be considered and conversion factors between both definitions have been proposed. A feeding study in dairy cows has been conducted and can be used for MRL setting in animal products. Chronic and acute consumer exposure assessments were conducted and, under restriction of an uncertainty related to the isomer ratio consumer is actually exposed to, did not show any indication of dietary risk. In soil under aerobic conditions fenpropidin exhibits moderate to high persistence and has the potential to accumulate when used in successive years. When it degrades it forms the major soil metabolite CGA 289267 (accounting for a maximum 10.6% of applied radioactivity (AR) at 8 degrees C) which exhibits low to moderate persistence. Mineralisation of the benzylic bridge radiolabel to carbon dioxide accounted for 16-32% AR after 90-92 days (22 degrees C). The formation of unextractable residues accounted for 9-19 % AR after 90-92 days. Fenpropidin is immobile or exhibits slight mobility in soil, CGA 289267 exhibits high to medium mobility in soil. There was no indication that adsorption of either fenpropidin or CGA 289267 was pH dependant. In dark natural sediment water systems fenpropidin degraded exhibiting moderate to medium persistence to the metabolite CGA 289267 found primarily in the water of the system (maximum 1314% AR). The terminal metabolite, CO2, accounted for 11-60 % AR at 84 days (study end, benzylic bridge radiolabel). Unextracted sediment residues a minor sink representing around 8 % AR at study end. The necessary surface water and sediment exposure assessments were appropriately carried out using the agreed FOCUS scenarios approach for fenpropidin at steps 3 & 4, with spray drift mitigation being applied at step 4. For the metabolite CGA 289267 appropriate FOCUS step 3 calculations were carried out. These values are the basis for the risk assessment discussed in this conclusion. There is the potential for short range atmospheric deposition to surface water from fenpropidin that may volatilise at the time of application and from plant surfaces for around 24 hours after application. The potential for groundwater exposure from the applied for intended uses by fenpropidin and its soil metabolite CGA 289267 above the parametric drinking water limit of 0.1 mu g/L was concluded to be low in geoclimatic situations that are represented by all 9 FOCUS groundwater scenarios. The first-tier risk assessment for birds resulted in TERs below the Annex VI trigger for the acute scenario in the Northern European GAP and in the long-term scenarios in the Northern and Southern European GAPs. Measured residue values and the focal skylark (Alauda arvensis) and yellowhammer (Motacilla flava) were agreed by the experts to be used in the refined risk assessment but not the suggested PT values. The acute TER for herbivorous birds was > 10 based on maximum initial measured residues. The meeting agreed to take into account in the long-term risk assessment that cereals would become not attractive as a food source for herbivorous birds and mammals soon after the first application when stem elongation starts. The reduction of residues in insects based on general considerations of growth of insect populations was not accepted since it was not based on measured residues. A more detailed consideration of insect populations in the relevant crop would be required before a scientifically sound and robust estimation of residue decline could be made. The FOCUS based interception factor of 0.5 for residues on weed seeds was rejected since weeds may have a similar or larger height as the crop during early cereal growth stages and extrapolation from deposition on soil surface was considered as not correct. A data gap was identified to refine the longterm risk assessment for herbivorous birds and insectivorous birds (Northern and Southern European uses). The Annex VI trigger was met for insectivorous mammals but breached in the first-tier acute and long-term risk assessment for herbivorous mammals. The suggest PT to refine the risk was not sufficiently supported by data and hence rejected. However based on accepted measured residue values the refined risk assessment resulted in TERs above the trigger indicating a low risk from the representative uses evaluated. The risk from secondary poisoning of earthworm-and fish-eating birds and mammals was assessed as low. The acute TERs for exposure to contaminated drinking water based on the 5-fold dilution of the sprayed solution resulted in TERs < 10 for birds. Further information on the drinking behaviour of birds was not submitted leaving some uncertainty via this route of exposure. However the application is to cereals and hence the formation of leaf puddles is unlikely. Algae were the most sensitive group of aquatic organisms driving the aquatic risk assessment. The risk assessment was based on an endpoint from a mesocosm study. The proposed NOEAEC of 6.8 mu g fenpropin/L was not agreed because long-lasting effects on Chlorophyceae were observed at a concentration of 1.4 mu g fenpropidin/L. The meeting agreed on a NOEC of 0.39 mu g fenpropidin/L (based on mean measured initial concentrations). It was suggested by the meeting of experts that an assessment factor of 1-3 should be applied at Member State level depending on the representativeness of the mesocosm to the local environmental conditions in the agricultural landscape. In the updated addendum of September 2007 (not peer-reviewed) the RMS recalculated the TERs based on FOCUS step 4 PECsw. With a no-spray buffer zone of 50 metres the TERs were above 1 in all drainage scenarios out of 6 but below 1 in all run-off scenarios. No full FOCUS step 4 scenario resulted in TERs > 3. The risk from metabolite CGA 289267 to aquatic organisms was assessed as low. Predatory mites were the most sensititve group of non-target terrestrial arthropods tested. Extended laboratory studies indicated a high in-field risk but also a potential of recolonisation due to rapid residue decline. The available studies did not cover the off-field exposure rates for Phytoseilus persimilis. An in-field no-spray buffer zone of 5 metres is required to achieve a rate low enough to conclude on a low risk to predatory mites based on the available studies. The acute risk to earthworms was assessed as low. The long-term TER for the Northern European use was calculated as 4.6. Since the TER value is not far below the trigger of 5 and the TER is based on very conservative PECsoil calculations (accumulation for 20 years) the experts agreed that the longterm risk to earthworms is low. The risk from the major soil metabolite CGA 289267 was assessed as low. The risk to bees, other soil non-target macro-organisms (collembola), soil non-target microorganisms, biological methods of sewage treatment was assessed as low for the representative uses in cereals.