Dec 13, 2004: What are some common poisonings associated with the winter season?


  • Carbon Monoxide – it is no surprise that CO is a concern in the wintertime.  Sources may include improperly functioning central gas heat furnaces, fireplaces and wood stoves improperly vented, and running the car in the garage on a cold morning to “warm it up”.  Other potential sources include using items indoors that are designed for outdoors or larger areas, such as kerosene heaters, charcoal grills and camp stoves. These may be used at times when the power is out in order to cook or provide heat.  All of these fuel-burning appliances can put of CO, which can build to dangerous levels in the home.  Carbon monoxide detectors should be used in homes that have any heat source or appliance that is gas powered.  Products designed for outside use should never be used indoors.  Examples of symptoms of CO poisoning include nausea, headache and fatigue.  CO poisoning can occur in the acute setting as well as following chronic “low-level” exposures.  Long-term sequelae if untreated can include chronic headaches, memory loss and reduction in cognitive skills.
  • Mercury Thermometers – the increase in febrile illnesses, such as the flu, leads to increased exposure to old mercury glass thermometers.  These thermometers may break in the mouth while the temperature is being checked or can drop on the floor and break causing mercury to spill out. The amount of elemental mercury in the thermometer is not toxic if ingested.  The risk comes with spills improperly cleaned up and disposed of improperly.  The local health department or solid waste management system can assist with clean up and disposal of old elemental mercury. Of note, the outdoor thermometers with red liquid do not contain mercury.
  • Car Care Products – the use of antifreeze and windshield washer fluid to prevent icing in the winter can lead to poisoning.  These products should always be kept in the original containers and out of the reach of children. Significant poisoning can occur with only a mouthful.
  • Sidewalk Salt – these products are designed to put on driveways and sidewalks to melt snow and ice.  The main ingredient is sodium chloride and could be toxic if ingested in significant quantities by children or pets.

Thanks to Kim Barker, PharmD, DABAT, the Managing Director of the Tennessee Poison Center, for contributing this “Question of the Week.”


As always, if there are any questions, call the Tennessee Poison Center at 1-800-222-1222.


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Donna Seger, M.D.

Medical Director, Tennessee Poison Center