The peer review of choline hydrogen phosphonate reached a broadly favorable regulatory conclusion: the representative grapevine and sports-turf uses were judged to have sufficient fungicidal efficacy, and no critical areas of concern or issues that could not be finalised were identified. The important qualification came in the non-dietary exposure assessment. Estimates for grape hand-harvesting re-entry exceeded the acceptable operator exposure level, or AOEL.
A review of two proposed uses
The review concerned BCP 1030F, a formulation containing 823.6 g/L of pure choline hydrogen phosphonate. Its representative foliar-spray uses were aimed at downy mildew on grapevine and fusarium patch on sports turf. The work was a regulatory peer review, drawing on a draft assessment report, consultation with Member States and the applicant, public consultation and expert consultation.
The efficacy conclusion was tied to those representative uses. Reviewers considered the proposed treatments sufficient against the target fungi. Their overall conclusion was that no critical areas of concern and no issues that could not be finalised were identified in the peer review.
Favorable toxicology findings, with a data caveat
The mammalian-toxicity findings were favorable on several endpoints. The assessment found no acute toxicity by oral, dermal or inhalation routes, and no skin or eye irritation or sensitisation. It judged the substance unlikely to be genotoxic, carcinogenic or a reproductive toxicant in humans, and found no neurotoxicity or immunotoxicity potential.
But the evidence base was not a full set of direct, long-term studies on choline hydrogen phosphonate. Direct toxicity evidence was limited to acute studies and a 28-day oral rat study. Reviewers completed the risk-assessment dataset by drawing on fosetyl-Al and other phosphonate-releasing substances, supported by QSAR information. Read-across, in plain terms, uses results from related substances to help assess an active substance when direct evidence is limited.
The exception was worker re-entry
The acceptable daily intake, or ADI, used for long-term dietary guidance was set at 1.57 mg per kilogram of body weight per day for choline hydrogen phosphonate and 0.70 mg/kg body weight per day for phosphonic acid. The reviewers used an uncertainty factor of 100. They did not consider an acute reference dose or an acute acceptable operator exposure level necessary. For skin contact, estimated absorption was 0.29% for the concentrate and 8.12% for the spray dilution.
Modeled operator and resident exposures were below the AOEL without specific risk mitigation. The grape hand-harvesting re-entry estimates exceeded it. This is an exposure estimate for a specified work activity, not a measured health outcome or a diagnosis.
Taken together, the result is a qualified regulatory verdict. For the representative uses, efficacy was sufficient and the peer review found no critical areas of concern or unresolved issue that could not be finalised. At the same time, the non-dietary assessment did not produce a uniformly favorable picture: operators and residents were below the AOEL without specific mitigation, while re-entry estimates for grape hand-harvesting exceeded it. The toxicology conclusion also depended substantially on evidence from related substances, a limitation to keep in view when interpreting the assessment.
Paper data and sources
Original title: Peer review of the pesticide risk assessment of the active substance choline hydrogen phosphonate.
Authors: European Food Safety Authority (EFSA), Fernando Álvarez, Maria Arena et al.
Journal/Repository: EFSA journal. European Food Safety Authority
Status: Peer-reviewed
First online: 2026-08-20
DOI: 10.2903/j.efsa.2026.10288
Original paper