A recent study from the Southern California's Keck School of Medicine suggests that there may be a link between having a dog and a child's sensitivity to air pollution. When children with and without pet dogs were exposed to air pollutants, those who had dogs had markedly more coughing, mucus, and bronchial symptoms in response. (All of these symptoms are related to asthma.)

Interestingly, no differences were noted in response to air pollutants in children who had cats or no pets at all. Cats are a known allergy and asthma trigger, but apparently do not have the same link to air pollution sensitivity that dogs do. Researchers are not sure why.

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