A SEPA study in 2001 and 2002 found that 89% of sample measurements did not detect any residues of chemicals used to treat sea lice.
And in the 11% of analysis where there were measurable concentrations of active
ingredients, residues were restricted to areas of seabed below and close to fish farms.
All results from outside these immediate areas were below SEPA environmental standards and there was no significant risk of environmental harm.
Andy Rosie, SEPA’s lead aquaculture specialist, said: “People are rightly concerned the environmental effects of fish farming should be minimised and carefully controlled.
“The initial results of this study have been encouraging, indicating SEPA’s regulatory approach appears to be providing an adequate level of environmental protection while permitting the use of authorised medicines to control sea lice infections in farmed salmon.”