New environmental quality standard (EQS) for emamectin benzoate (EmBz): consultation on the implementation timescales

Closed 24 Jul 2023

Opened 24 Apr 2023


This paper sets out Scottish Government's directions to the Scottish Environmental Protection Agency (SEPA) on the application of a new EQS for EmBz. This ensures that SEPA exercise its regulatory and river basin management planning functions. Emamectin benzoate is widely used in the fish farm industry to control sea lice in marine finfish farming.

The new standard for EmBz is lower than the standard SEPA has used previously to set discharge limits for marine finfish farms. We are seeking views on the timescale SEPA should implement the new standard reducing the discharge limits for these farms. This will enable consistency of the standard levels  across all regulated farms in order to achieve improved environmental quality.

We expect SEPA to apply the new standard immediately to all Controlled Activities Regulations Licence variations and new applications to protect the water environment from deterioration. However, we need to consider the implementation timescale before deciding when action to reduce discharge limits at existing farms should be taken.

Read the consultation paper 

Why your views matter

Fish production cycles at sea can last up to around 24 months. In identifying the appropriate timescale for applying the new EQS to existing discharges, we consider basing the implementation timescale on a production cycle, or multiple thereof. This is likely to be the best fit with planning and investment horizons across multiple operators.

We would like your feedback on what would be the appropriate timetable that provides marine finfish farm operators with a reasonable period to make any required adjustments to meet the new standards whilst not unduly delaying improvement in the quality of Scotland’s coastal waters.

What happens next

Following the closing date, all responses will be analysed and considered along with any  other available evidence. Responses will be published where we have been given permission to do so. An analysis report will also be made available.


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