US landfill fire sparks toxic smoke fears
Environmental regulators reassured people they faced no serious health risk from smoke billowing out of a burning landfill in Oklahoma.
The fire, in the state's second city, Tulsa, is understood to have been caused by a lightning strike and burned out of control for more than a day despite firefighter efforts to put it out.
Airborne monitoring suggests the smoke does not contain toxic vapours.
But the Environmental Protection Agency (EPA) and Oklahoma Department of Environmental Quality (ODEQ) are warning even non-toxic smoke can irritate the respiratory system and worsen symptoms for those with breathing difficulties and conditions such as asthma and emphysema.
Steve Thompson, ODEQ executive director, said: "ODEQ appreciates the quick response of EPA in this matter.
"ODEQ and EPA will remain at the landfill throughout the day to place additional air quality monitors and gather data from those that have already been placed."
ODEQ continues to encourage individuals with these pre-existing respiratory conditions to avoid the smoke by remaining indoors.
The fire captain in charge of efforts to battle last Wednesday's (August 4) blaze reportedly said not enough water could be got to the site to put it out and early efforts had focused on protecting surrounding buildings.
The fire was eventually extinguished by smothering it with soil. The landfill serves many small waste firms that collect municipal rubbish from the city's suburbs.
It takes in around 600 tonnes of waste per day, which are then shipped to an energy-from-waste plant elsewhere in the city.
Operators say the fire was sparked by a lightning strike. The regulators gave the order on Thursday to shut the gates until the blaze could be brought under control.
EPA regional administrator, Al Armendariz, said: "Emergencies such as this one demonstrate the importance of the continued planning and cooperation between ODEQ and EPA."