LINCOLN – Carbon monoxide detectors saved the lives of two families last week, including a mother and daughter who live on South Road, Fire Chief William Lee said Thursday.

The detectors sounded at the discovery of lethal amounts of the odorless, colorless gas, allowing the families to call the Fire Department for help and flee the homes before being overcome by the poison, Lee said. In both cases, firefighters verified what the detectors indicated, he said.

“If the gas had gone undetected, in both cases it could have been fatal,” Lee said Thursday. “Those families are very fortunate to have had detectors.”

The first reported case was on Friday night on Albert Drive. The second case was reported at 7:30 p.m. Wednesday. Lee declined to identify the families. On Albert Drive, a malfunctioning boiler caused the poison gas to be released. A gas-burning electrical generator malfunction created the gas on South Road, Lee said.

The cases were the first reported in Lincoln in at least four years, Lee said.

But poisonings – and sometimes fatalities – have been reported occasionally throughout the state, said Andrew Smith, state toxicologist and director of the environmental health unit with the Maine Bureau of Health.

The total number of fatalities reported in Maine was not immediately available Thursday, but a Greenfield man died last year of asphyxia and inhalation of products of combustion, including carbon monoxide, during a fire. In 2004, residents of Hearthside Extended Care Facility in Sidney were taken to the hospital twice in three days for carbon monoxide poisoning, apparently caused by a malfunctioning furnace.

Most studies blame carbon monoxide poisoning for causing about 2,000 fatalities annually nationwide.

Poisonings most often occur in winter, when windows are closed and secondary heaters are used, Lee said. Any unvented fuel-burning appliance, especially gas or propane, can produce deadly levels of carbon monoxide. The gas is tasteless, odorless and can overcome the occupants of a house or apartment before they realize a risk exists.

Mild cases of carbon monoxide poisoning produce sleepiness, headaches, dizziness, blurred vision, irritability and inability to concentrate. More severe cases cause nausea and vomiting, shortness of breath, convulsion, unconsciousness and death.

Most often, Smith said, carbon monoxide poisoning is confused with the flu, except with the former, no temperature increase occurs. The best first aid for carbon monoxide poisoning is lots of fresh air followed immediately by a visit to an emergency room.

Smith said Maine was first awakened to the lethal effects of carbon monoxide poisoning in the aftermath of the 1998 ice storm; this period accounts for almost half of the 1,056 cases of nonfatal poisonings reported statewide from 1998 to 2002 at hospitals and clinics.

Health officials think the poisonings occurred because of widespread and lengthy power outages that forced people to use gas-powered generators or alternative heat sources that were not properly placed or ventilated, Smith said.

“The big message there was that if you’ve got these and they are operating, you really need to put them outside,” Smith said.

State health officials responded to the 1998 poisonings by starting to track carbon monoxide poisonings. They are now working with the Atlanta-based U.S. Centers for Disease Control and a $550,000 annual, three-year grant to establish an environmental public health tracking system, Smith said.

A carbon monoxide poisoning surveillance system is part of that effort. State officials also are about a month away from launching a statewide survey that will identify households with carbon monoxide detectors, detectors with battery-powered backups, and homes that use alternative energy sources, he said.

“The message there is that everyone should have a carbon monoxide detector that has a battery-powered backup,” he said.

About the gas

Carbon monoxide is a colorless, odorless and highly poisonous gas produced by the incomplete combustion of material consisting of carbon.

Any unvented fuel-burning appliance, especially gas or propane, can produce deadly levels of carbon monoxide, which can quickly overcome occupants of an enclosed space before they realize a risk exists.

Nationwide, about 2,000 fatalities are blamed every year on carbon monoxide poisoning.