New European guidelines are about to be published by the SANTE’ Directorate General for Health and Food Safety to help the development, registration and use of active semiochemical substances as agricultural pesticides for the control of insect pests. In developing the new guidelines, the specific properties of these substances have been taken into account. They often target a specific action by modifying the behavior of the targeted species, can be used at concentrations similar to those found in nature, and may dissipate and/or degrade rapidly. For these reasons, it is expected that many semiochemical products pose a low risk to human health and the environment. Studies on their efficacy as well as on their impact on the environment and health have demonstrated that such substances may provide effective means of pest control at low volumes, and at minimal risk.
By definition, semiochemical products are substances produced by plants, animals and other organisms that provoke a behavioral or physiological response in individuals of the same or different species. They include allelochemicals (allomones, kairomones and synomones), pheromones (with an intraspecific action), and straight-chain lepidopteran pheromones (SCLP). The latter are a group of aliphatic non-branched chain pheromones, with 9-18 carbon atoms containing up to three double bonds and a terminal functional group (alcohol, acetate or aldehyde). SCLP include most pheromones naturally produced by lepidopterans. In order to be marketed in the EU, semiochemical products must be approved in accordance with Regulation 1107/2009 and the dossier must be compiled following the provisions of Part A of Reg. 283/2013 (for the active substance) and Part A of Reg, 284/2013 (for the formulated product). The presentation of the dossiers must comply with the requirements of the Uniform Principles (Reg. 546/2011). The evaluation is carried out at EU level according to the zone subdivision (North, Centre, and South). In the very important meetings preceding the formal authorization request, the applicants will discuss with the respective competent authorities (for Italy the Ministry of Health, Department of Veterinary Public Health, Food Safety and collegial organs for the health protection, Directorate-General for the Hygiene and Safety of Foods and Nutrition, and Office VII Plant Protection Products) all aspects related to Good Agricultural Practices (GAP), labels, target-insect biology, application methods, chemical composition and physical-chemical data of the formulation, co-formulants, efficacy data, and an environmental and human health risk assessment. These will obviously be confidential meetings in compliance with Reg. 1107/2009. The formal submission of the dossier will precede the actual assessment. The expected types of applications include (1) products in recyclable containers (passive with a continuous release of the semiochemical product and active ingredients with batch release), (2) non-recyclable products (micro-encapsulated forms, measurable in matrix, granular seed treatments). When passive and measurable in matrix containers are used, the exposure is through a vaporizable phase and the assessed risk is low. In the other cases (contact or oral exposure, dressed seeds or granules), a detailed exposure assessment is absolutely necessary.
The guidelines contain both the procedures for assessing natural exposure levels, even when the number of releasing organisms is not known, and the mathematical models for calculating the final concentration resulting from the semiochemical product application ( steady state single-cell model or fixed box model). The other parts of the dossier must include enough information on the product’s identity and its physical-chemical properties so as to identify both the active substance and the impurities. If the former consists of a mixture of isomers, their ratio in the technical product must be specified. Technical equivalence with another product is expected and in such a case, the ratio of isomers may be different from that of the reference product. For the analytical methods, the provisions of UE Regulations no.283/2013 and no.284/2013 are applied. Aspects of human toxicology will have to be specified, keeping in mind that it is possible to extract (read across
) data from other active semiochemical substances. The guidelines contain detailed information on the environmental compartments for which exposure (via contact or inhalation) of technicians, workers, bystanders, and residents is expected for products in both recyclable and non-recyclable containers.
This information greatly helps both the applicants in preparing the dossier and the evaluators thereof. As regards residues, it being understood that EC Reg. 396/2005 (quantification limits) and SANCO guidelines no.11188/2013 apply, and in the case where pheromone exposure is only through the volatile phase, risk characterization is to be considered concluded. The same applies to the assessment of environmental fate and behavior as well as to the assessment of ecotoxicological aspects. In all the other cases of exposure, all information that enables a complete assessment and characterization of risk is needed. Once again, the tables that enable identifying the exposure of non-target organisms in the various environmental compartments and for the various types of application are helpful. As regards efficacy assessment, the reference is the SANCO/10054/2013 guidelines, keeping in mind that semiochemical products can provide complete or partial control, or contribute to controlling insect pests. Therefore appropriate controls in accordance with the EPPO 1/264 (1) guideline on "Mating disruption pheromones" should always be included.