Attempts to keep warm using generators or other heat sources during power outages caused by heavy snowfall may have led to two deaths and more than two dozen others being sickened by carbon monoxide poisoning.

Another man may have died while shoveling snow.

A man and his daughter were found dead today, the apparent result of carbon monoxide poisoning that resulted from the use of a generator, according to the Allegheny County Medical Examiner's office. George Mateya, 60, and his daughter, Joelle Mateya, 19, were using a generator for heat because of an electrical outage at their home in McKeesport.

Their bodies were found at 12:18 a.m. today at their home on Milburn Street by a friend who was concerned because he hadn't heard from them Saturday.

Dr. Donald M. Yealy of the UPMC Health System said that more than two dozen people have been treated in the system's hospitals for carbon monoxide poisoning between Saturday and today. Three more were treated in the West Penn Allegheny health system, a spokeswoman said.

Dr. Yealy said the common thread in the poisonings was the improper use of generators or other sources to make up for the loss of electricity. Generators, which burn fuel, should be used outside to prevent a buildup on carbon monoxide indoors.

According to the U.S. Environmental Protection Agency, carbon monoxide is a byproduct of combustion. Fumes are produced as the exhaust emission from the burning of such fuels as natural gas, wood, and coal. The less complete the burning, the more carbon monoxide is generated.

A fume that can't be seen or smelled, carbon monoxide can be produced in deadly levels by malfunctioning machines or it can accumulate to a toxic level in areas that are not well ventilated, according to the EPA.

Also, the examiner's office is investigating what could be a third weather-related death. A 57-year-old man, whose name hasn't been released, was found dead in his North Side home Saturday night, not long after he had been shoveling a sidewalk at his sister's nearby home.

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