Published Friday, 08 March 2013
Belfast Lagan, from the Waterfront Hall. (© UTV)
The city experienced high levels of particulate matter on Friday.
Moderate levels have also been recorded in the Lisburn area.
Meanwhile, the Londonderry area has been experiencing moderate levels of both particulate matter and nitrogen dioxide.
A Department of the Environment statement said the air pollution is likely to be associated with the build up of emissions from vehicles and home heating.
"Pollutant levels are expected to decline as we experience wet, unsettled weather, but they could increase to high again with colder, drier conditions towards the end of this weekend and into early next week," the statement read.
Air Quality NI telephone: 0800 556 677
During periods of High Air Pollution the symptoms of people with lung or heart disease may worsen, the department advised.
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