Conclusion on the peer review of the pesticide risk assessment of the active substance metobromuron

The conclusions of the European Food Safety Authority (EFSA) following the peer review of the initial risk assessments carried out by the competent authority of the rapporteur Member State France, for the pesticide active substance metobromuron are reported. The context of the peer review was that required by Commission Regulation (EU) No 188/2011. The conclusions were reached on the basis of the evaluation of the representative use of metobromuron as a herbicide on potatoes. The reliable endpoints concluded as being appropriate for use in regulatory risk assessment, derived from the available studies and literature in the dossier peer reviewed, are presented. The consumer risk assessment should be considered provisional pending the outcome of the requested toxicological information on the metabolites included in the plant residue definitions. A high long-term risk to birds could not be excluded with the available data

Conclusion on the peer review of the pesticide risk assessment of confirmatory data submitted for the active substance dimethoate

The conclusions of the European Food Safety Authority (EFSA) following the peer review of the initial risk assessment carried out by the competent authority of the rapporteur Member State the United Kingdom, for the pesticide active substance dimethoate are reported. The context of the peer review was that requested by the European Commission following the submission and evaluation of confirmatory mammalian toxicology, residues and ecotoxicology data. The conclusions were reached on the basis of the evaluation of the representative uses of dimethoate as an insecticide on sugar beet and protected lettuce. Concerns are identified

EFSA Panel on Plant Protection Products and their Residues (PPR); EFSA Scientific Opinion on the science behind the revision of the guidance document on dermal absorption

Following a request from the EU Commission, the EFSA PLH Panel conducted a risk assessment for the EU territory of pospiviroids affecting solanaceous crops, identified and evaluated risk reduction options and evaluated the EU provisional emergency measures targeting Potato spindle tuber viroid (PSTVd). The risk assessment included PSTVd, Citrus exocortis viroid, Columnea latent viroid, Mexican papita viroid, Tomato apical stunt viroid, Tomato chlorotic dwarf viroid, Tomato planta macho viroid, Chrysanthemum stunt viroid and Pepper chat fruit viroid. Four entry pathways were identified, three involving plant propagation material, with moderate probability of entry, and one involving plant products for human consumption, with low probability of entry. The probability of establishment was considered very high. Spread was considered likely within a crop and moderately likely between crop species, with exception of spread to potato, rated as unlikely. The probability of long distance spread within vegetatively propagated crops was estimated as likely/very likely. The direct consequences were expected to be major in potato and tomato, moderate in pepper, minimal/minor in other vegetables and minimal in ornamentals. Main risk assessment uncertainties derive from limited knowledge on pospiviroids other than PSTVd, although all pospiviroids are expected to have similar biological properties. Management options to reduce risk of entry, spread and consequences were identified and evaluated. No management options can prevent establishment. Examples of successful PSTVd eradication are linked to timely and strict implementation of measures. Uncertainty exists on the effectiveness of risk reduction strategies targeting only one pathway. The EU provisional emergency measures appeared to have significantly reduced PSTVd incidence in Solanum jasminoides and Brugmansia sp., even though eradication from the EU is so far incomplete. The low PSTVd incidence in food crops did not permit to conclude whether the reduction in PSTVd prevalence in ornamentals led to a reduction in outbreaks in food crops

International Frameworks Dealing with Human Risk Assessment of Combined Exposure to Multiple Chemicals

The development of harmonised terminology and frameworks for the human risk assessment of combined exposure to multiple chemicals (“chemical mixtures”) is an important area for EFSA and a number of activities have already been undertaken, i.e. in the fields of pesticides and contaminants. The first step prior to a risk assessment of combined exposure to multiple chemicals is problem formulation defining the relevant exposure, hazard and population to be considered. In practice, risk assessment of multiple chemicals is conducted using a tiered approach for exposure assessment, hazard assessment and risk characterisation. Higher tiers require increasing knowledge about the group of chemicals under assessment and the tiers can range from tier 0 (default values, data poor situation) to tier 3 (full probabilistic models). This scientific report reviews the terminology, methodologies and frameworks developed by national and international agencies for the human risk assessment of combined exposure to multiple chemicals and provides recommendations for future activities at EFSA in this area

Impact of bacterial spot outbreaks on the phytosanitary quality of tomato and pepper seeds

The impact of disease outbreaks on the phytosanitary quality of seeds was investigated for two pathosystems: tomato-Xanthomonas vesicatoria and pepper-Xanthomonas euvesicatoria. This study, which was performed in Italy and Serbia, aimed to evaluate the season-to-season transmission of phytopathogenic regulated bacteria associated with phytosanitary risks posed by seeds produced in areas where bacterial infections are possible. For each pathosystem, field plots were experimentally inoculated to simulate an initial infection rate of 1%, 5% and 15%. The area under the disease progress curve (AUDPC) was calculated for each field plot, the seeds produced were analysed to determine the contamination level and rate, and the plant-to-seed transmission was evaluated by a seedling grow-out (SGO) assay. To investigate transmission under field conditions, a second-year experiment was performed, wherein seeds collected from the first year were used to establish new field plots. During the first growing season, AUDPC values were positively correlated with the percentages of initial infection for each pathosystem. Seed contamination levels in pepper ranged from 34 to 100CFUg(-1), and the contamination rate ranged from 1.50% up to 3.17% for X. euvesicatoria, whereas processing and fresh market tomato seeds produced both in Italy and Serbia were not infected by X. vesicatoria. During SGO assays and the second cropping year, no symptoms were observed in either tomato or pepper plants. Therefore, the calculated pepper seed contamination rate for X. euvesicatoria appeared to be less than the threshold necessary to initiate a disease outbreak. Finally, all seeds obtained during the second cropping year were uninfected

Pest categorisation of Anthonomus quadrigibbus

The Panel on Plant Health performed a pest categorisation of the weevil Anthonomus quadrigibbus Say, (Coleoptera: Curculionidae), for the EU. A. quadrigibbus is a well-de fi ned and distinguishable species, recognised as an occasional pest of apples, pears and sour cherries in North America where it also feeds on a range of wild rosaceous plants such as Crataegus and Amelanchier . Adults feed on leaves, fl owers and fruit. Feeding damage to fruit reduces quality. Females oviposit into young fruit, causing surface blemishes and resulting in distortion as the fruit develops. Marketability is subsequently reduced. Larvae and pupae develop within host fruit. Most infested fruit fall prematurely, reducing yield. A. quadrigibbus was regarded as a more serious pest in the early 20th century. A. quadrigibbus is not known to occur in the EU and is listed in Annex IIAI of Council Directive 2000/29/EC under the synonym Tachypterellus quadrigibbus . Host plants for planting and infested fruit could potentially provide a pathway into the EU. Considering the climatic similarities between North America and Europe, and that wild and commercial hosts occur widely within the EU, A. quadrigibbus has the potential to establish within the EU. There would be one generation per year, as in North America. Impacts could be expected in apple, pear and perhaps sour cherry orchards. The level of impacts would be uncertain. There is also uncertainty regarding whether A. quadrigibbus would extend its host range to include other Rosaceae within the EU. Phytosanitary measures are available to reduce the likelihood of introduction of A. quadrigibbus . All criteria assessed by EFSA for consideration as a potential Union quarantine pest are met. As A. quadrigibbus is not known to occur in the EU, this criterion assessed by EFSA to consider it as a Union regulated non-quarantine pest is not met

Pest categorisation of Gymnosporangium spp. (non-EU)

Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of Gymnosporangium spp. (non-EU), a well-defined and distinguishable group of fungal plant pathogens of the family Pucciniaceae affecting woody species. Many different Gymnosporangium species are recognised, of which at least 14 species are considered not to be native in the European Union. All the non-EU Gymnosporangium species are not known to be present in the EU and are regulated in Council Directive 2000/29/EC (Annex IAI) as harmful organisms whose introduction into the EU is banned. Gymnosporangium spp. are biotrophic obligate plant pathogens. These rust fungi are heteroecious as they require Juniperus, Libocedrus, Callitropsis, Chamaecyparis or Cupressus (telial hosts) and rosaceous plants of subfamily Pomoideae (aecial hosts) to complete their life cycle. The pathogens could enter the EU via host plants for planting (including artificially dwarfed woody plants) and cut branches. They could establish in the EU, as climatic conditions are favourable and hosts are common. They would be able to spread following establishment by movement of host plants for planting and cut branches, as well as by natural dispersal. Should Gymnosporangium spp. (non-EU) be introduced in the EU, impacts can be expected in orchards, ornamental trees and nurseries. On telial hosts, these pathogens cause galls on stems, twigs and branches, and fusiform swellings on stems. Foliar infections on aecial hosts may lead to severe defoliations. The main knowledge gap concerns the limited available information on the biology, distribution range and impact of several non-EU Gymnosporangium spp. The criteria assessed by the Panel for consideration of Gymnosporangium spp. (non-EU) as potential quarantine pests are met, while, for regulated non-quarantine pests, the criterion on the pest presence in the EU is not met

Effectiveness of in planta control measures for Xylella fastidiosa

This opinion updates the information included in the previous EFSA Scientific Opinion concerning the in planta control measures for Xylella fastidiosa, with a systematic review and critical analysis of the potential treatment solutions that have been published against this pest so far. The output of this opinion focuses on the application of chemical or biological treatments on living plants. In vitro studies, hot water treatments, use of resistant varieties and vector control are excluded from the review. The use of antibiotics is not considered due to the risk of antimicrobial resistance development. The use of weakly virulent or avirulent strains of X. fastidiosa is covered in this review, although this organism is an EU quarantine plant pest and its introduction in the EU territory is banned. Experiments were recently conducted to assess the effect of application of zinc, copper, and citric acid biocomplex, of N-acetylcysteine, and of ‘diffusible signal factor’ (and of its homologs). Their results showed that these control measures were sometimes able to reduce symptoms caused by X. fastidiosa. Recent experiments also showed that several species of endophytic microorganisms, some bacteriophages and inoculation of weakly virulent/avirulent strains of X. fastidiosa could offer some protection against the Pierce’s disease. However, based on the reviewed results, the Panel concludes that, although several published experiments show some effects in reducing symptoms development, the tested control measures are not able to completely eliminate X. fastidiosa from diseased plants. The Panel confirms as previously stated that there is currently no control measure available to eliminate the bacteria from a diseased plant in open field conditions

Treatment solutions to cure Xylella fastidiosa diseased plants

This opinion addresses the question of the efficacy of current treatment solutions to cure Xylella fastidiosa diseased plants, and discusses the experimental treatments under evaluation by two research groups in Apulian olive orchards infected by strain CoDiRO (Complesso del Disseccamento Rapido dell'Olivo). The increasing problems from newly emerging vascular bacterial diseases and the limited success to cure plants from such infections have stimulated numerous studies on treatments with chemical and biological compounds. Under field conditions, various formulations of copper and zinc as spray or root drench are currently used while further options, for example the application of bioactive substances, are at an experimental stage. In Apulia, preliminary results from intensive treatments with such formulations, in combination with the use of good crop management practices, reported more vigorous new growth of diseased trees. However, results provided so far confirmed the continued presence of X. fastidiosa after the treatments under evaluation. This is in agreement with current knowledge that there are no means to cure plants from this bacterial disease, in the sense of eliminating the pathogen from plant tissues. The reported positive response of the treated olive trees is most probably due to the effect of micronutrients and other bioactive compounds that, together with soil cultivation and agronomical practices, improve the vigour of the plants and their resilience to stress caused by bacterial infections. Notwithstanding the preliminary status of these findings, the Panel acknowledged the potentially positive effects of such treatments in prolonging the productive phase of olive trees and their putative relevance for the management of olive orchards, particularly in the containment area where eradication of the pathogen is considered no longer possible. The Panel also concluded that long-term studies are needed to confirm that the reported positive effects on crop performance can be sustained over many years