EFSA has concluded that the available information on the microbial fungicide Trichoderma harzianum T78 is insufficient to determine whether its secondary metabolites meet regulatory criteria for environmental exposure, leaving the risk assessment for non-target organisms incomplete. The conclusion, published on 27 July 2026, follows a peer review of the initial risk assessment carried out by the Netherlands, the rapporteur Member State, for the active substance used as a fungicide on lettuce.
The assessment, required under Regulation (EC) No 1107/2009, evaluated the representative uses of Trichoderma harzianum T78 applied via overall drench, drenching equipment, and drip irrigation to control Sclerotinia spp. The applicant, Symborg Business Development S.L., submitted the application on 26 February 2020, with admissibility recognised on 4 September 2020. The Netherlands provided the draft assessment report on 29 March 2024, and EFSA initiated the peer review on 10 July 2024, including a public consultation and expert teleconference on 14 November 2024.
EFSA found no critical areas of concern regarding the identity, physical and technical properties, or analytical methods of the active substance. In mammalian toxicology, the evidence was sufficient to exclude secondary metabolites of potential concern, and no data gaps were identified. For residues, one of five criteria for inclusion in Annex IV of Regulation (EC) No 396/2005 was met, but the overall MRL application remains pending approval of the active substance.
However, in the area of fate and behaviour in the environment, EFSA identified a data gap: the available information is insufficient to determine whether the metabolites known to be produced, particularly peptaibols, meet the criteria set out in Commission Regulation (EU) No 283/2013 regarding their presence in the microbial pest control product and/or their in-situ production in the environment. Trichoderma harzianum T78 can be expected to persist and multiply in soil at concentrations considerably higher than natural background levels, especially with repeated applications over years. Consequently, the risk assessment for non-target organisms exposed to potentially produced secondary metabolites could not be finalised.
The peer review report, including comments from Member States and the applicant, is publicly available. EFSA's conclusion will inform the European Commission's decision on whether to approve the active substance under EU pesticide rules.