AN interactive map shows where a radioactive gas is present in north Essex which is colourless, odourless and tasteless.

Radon is formed by radioactive decay from the small amounts of uranium that can be found naturally in all rocks and soils. This means it is everywhere.

Public Health England, however, states that "every building contains radon but the levels are usually low.

"The chances of a higher level depend on the type of ground."

Public Health England has released a map showing where high levels are more likely. This can be found through this link.

The darker the colour, the greater the chance of a higher level.

The chance is less than one home in a hundred in the white areas and greater than one in three in the darkest areas.

A broad look at north Essex shows low levels of radon across most areas, with hotspots in some particular areas.

Here are how some locations in north Essex fare according to the map:

Harwich 

Gazette:

The majority of Tendring is clear on the map, but there are a few spots as you head further out.

Part of old Harwich is deemed to have a risk of radon.

Walton

Gazette:

The area surrounding the Naze in Walton is also coloured yellow.

This colour means there is a one to three per cent maximum radon potential.

West Bergholt

Gazette:

The majority of central Colchester is clear on the map, but there are a few spots as you head further out.

Part of West Bergholt, near to Colchester Golf Club, is deemed to have a risk of radon.

Suffolk border

Gazette:

A particularly large set of hotspots stretches from south of Great Cornard, into Bures and across to Nayland.

Kelvedon

Gazette:

Parts of Kelvedon surrounding the A12 are also in the yellow category, with a one to three per cent maximum radon potential.

It is a minor risk, but there is a risk of radon exposure in the area.