We’re in the midst of winter, which means that as soon as you get home, you probably close your windows and doors tightly and run to the thermostat, anxious to turn up the heat and climb under a blanket. But as the freshly heated air rolls through the house and you snuggle deep into your couch, have you stopped to think about else might be hibernating in your home? The truth is that winter air often means more for you than colder temperatures. Keeping your house airtight can lead to an increased level of air pollution, including rising levels of...