Major salmon farmer Marine Harvest has expressed concern about the use of chemicals to combat fish diseases, after data from the Scottish Environment Protection Agency (SEPA) show that about 20 million liters of hydrogen were dumped in Scottish waters, The Sunday Times reported.

This chemical compound is frequently used to treat topical skin and gill infections.

According to SEPA, more than 160 farms resorted to the chemical in 2015 to tackle parasites such as sea lice.

Hydrogen peroxide is regarded as environmentally safe as it quickly breaks down into its constituent parts of hydrogen and oxygen. The chemical does not kill parasites, but stuns them. As farmed fish knock against each other in crowded pens, the parasites fall off.

However, there is evidence that the chemical harms fish. Academics from Bergen University in Norway recently presented a report showing that hydrogen peroxide weakens the immune system of fish by damaging gill tissue and protective mucosal layers.

After the treatment, fish need at least two weeks to recover during which time they are susceptible to aquatic pathogens.

In 2001, Compassion In World Farming (CIWF) warned that hydrogen peroxide posed “serious animal welfare drawbacks”.

The SEPA data, obtained by the Global Alliance Against Industrial Aquaculture, shows that since 2010, the chemical has been used in increasing quantities, sometimes with devastating effects.

Source: FIS // Original Article