CAB Publication date
ASC Aquaculture Stewardship Council 2021-09-14
Certificate holder Date of submission
Unit of certification Species
Country Reference to other Q&As
Document reference Version
Salmon 1.3
Indicator Other relevant indicator/clause
5.2.5 5.2.6 5.2.7 Appendix VII: Parasiticide Treatment Methodology
Background info
Supporting evidence

As per Rationale of Criteria 5.2, the release of veterinary chemicals in the marine environment is of ongoing concern to ASC as its stakeholders. Indicators 5.2.5 – 5.2.7 intent to minimise the number of in situ sea lice treatments as a means to limit the amount of veterinary chemicals/medicinal products that enter the marine environment. Under the WMNT-calculation (see Appendix VII), a number is set to any in situ treatment given.

However, recent technological innovation (e.g. the Benchmark CleanTreatÒ system) has enabled producers to treat for sea lice in a closed contained system (thus no longer in situ) that applies a treatment water purification step in order to remove veterinary chemicals below quantifiable levels, prior to discharge.

Using treatments systems that do not treat nor discharge in situ (e.g. the Benchmark CleanTreatÒ system), the amount (and thereby the risk) of veterinary chemicals/medicinal products that enter the marine environment is mitigated.

When farms apply these systems, which count shall be allocated under the WNMT-calculation?

Effective date
September 14, 2021

For systems that 1) do not treat in situ and 2) do not discharge effluent in the marine environment without prior sufficient purification, a count of 0 (zero) shall be allocated to the WNMT.


Confidental Infomation