VSNI statement on EMA review of companion animal parasiticides

In recent years, emerging research has highlighted concerning levels of parasiticide chemicals in UK waterways and elsewhere, with companion animal use considered the most plausible source. Currently, there is a gap in the environmental impact assessments undertaken for companion animal products. These assessments typically stop at Phase 1 on the basis that “non-food animals are not intensively reared” and that “products used in these animals are usually individual treatments,” resulting in “fewer environmental concerns.” However, this assumption has since been challenged by up-to-date research, and we welcome the European Medicines Agency (EMA) review into this issue.

The EMA proposes to develop a methodology to assess the environmental risks of these products, utilising the current framework used for large animal product assessments while acknowledging that a tailored approach may be required due to the many knowledge gaps and nuances associated with companion animal products. This framework has the potential to reduce the environmental impact of future licensed products.

In response to the Concept paper for the development of a guideline on the methodology of environmental risk assessment for ectoparasiticidal VMPs for cats and dogs, we would like to offer the following comments and recommendations. These recommendations are for all parasiticide products available i.e., all formulations and including those that are available over-the-counter as well as from veterinary practices.

Firstly, we commend the EMA’s recognition of the significant data and knowledge gaps in this field. The proposal to develop exposure scenarios to address gaps relating to fate, effects, and exposure risk is welcome. In light of this, we recommend the development of multiple scenario models. These should account for differences between species (e.g., cats vs. dogs), indoor vs. outdoor lifestyles, and activities that pose heightened exposure risks (e.g., frequent swimming or grooming).

We also recommend that cumulative effects are assessed, rather than relying solely on data from individual product use. In addition, we would welcome greater focus on risks posed to non-target invertebrates and humans, from both high-level exposure and chronic sub-lethal exposure. Further, we strongly support the inclusion of monitoring strategies for environmental residues, including surface water, sediment, and soil. Finally, we recommend that full life-cycle analyses are conducted for high-risk products, taking into account both individual and cumulative data, including product fate and disposal routes.

Secondly, we commend the EMA’s proposal to introduce a Phase 2 methodology for companion animal VMPs. We suggest strengthening this by clearly defining trigger criteria, such as ecotoxicity potential, intended use, and route of administration, so that high-risk products beyond parasiticides are also assessed for environmental impact.

We also encourage the introduction of mandatory mitigation measures. For high-risk products, external labelling to communicate environmental hazards should be required. Guidance on the correct use and disposal of these products should also accompany them, alongside recommendations for non-chemical control methods where appropriate. Additionally, we propose that the sale of high-risk products be restricted to prescription-only status rather than over-the-counter availability.

Where environmental contamination risk is high, we recommend that the methodology specify procedures for ongoing monitoring (e.g., routine sampling downstream of urban areas or dog swimming sites) and establish clear actions to be taken when contaminant thresholds are exceeded.

Finally, we urge the EMA to retrospectively assess companion animal products currently on the market, in particular topical and oral parasiticides such as imidacloprid, fipronil, and isoxazolines. A substantial number of such products are already widely used and may be contributing to unacceptable levels of chemical contamination in aquatic and terrestrial environments. Retrospective environmental assessment is essential if we are to effectively reduce the ecological impact of veterinary medicines going forward.

Thank you for the opportunity to comment on this important initiative. We trust that the EMA will continue to take seriously the environmental implications of ectoparasiticidal VMPs used in cats and dogs and adopt a robust guideline that protects ecosystems while enabling safe and effective parasite control.