It may look nasty, but the strange red discolouration of sea water around the island is nothing but a ’natural phenomenon’ according to lab reports.

The Department of Infrastructure is reassuring residents that the suspicious looking rusty-coloured patches that have recently been spotted in Douglas, Laxey and Ramsey bays are nothing to be concerned about.

This comes after worries that the substance was raw sewage.

However, scientists from the government laboratory confirm that the discolouration is caused by a type of algae called noctiluca scintillans.

Dr Kevin Kennington, marine monitoring officer at the government laboratory, said: ’This particular algae is non-toxic and regularly blooms during the summer months in the Irish Sea.

’This species has some interesting traits.

’For example, it is a plant that does not rely on photosynthesis to feed itself.

’Instead it engulfs other microscopic organisms to gain nourishment - so it’s a plant that eats other plants.

’The species name noctiluca means "shines by night" and the blooms of the organism around the island may provide some spectacular bioluminescence along the shore line at night.

’The plants are able to emit light when agitated, possibly as a defence mechanism to stop themselves from being eaten.

’These light emitting properties are reflected in the species’ common names which are "Sea Sparkle" or "Fire of the Sea".’

Although the algae is non-toxic there is a possibility that dense blooms will also attract other organisms such as jellyfish which feed on noctiluca.

Therefore the public are advised to avoid swimming through the discoloured patches.

Environment Minister, Geoffrey Boot MHK, said: ’A number of people have raised this issue with me over the past few days and I hope this explanation of what is a perfectly natural event provides clarity.’

Over the weekend residents were warned to avoid Laxey beach after it was suspected that the red patches of sea water were raw sewage.

On July 6 Garff Commissioners wrote: ’We’ve received a call from a member of public advising that currently raw sewage has been seen along the tide line on Laxey beach.’

The commissioners later notified the public that samples had been taken and were being assessed by the government laboratory andthey were waiting to hear back about the results.