Most people don’t realize that indoor air quality is a cause for concern. Here is a link to introductory material from the EPA on this topic.
If you weren’t aware, cleaning with steam will atomize toxic chemical residue left in household surfaces. Always remember to open windows or, if you’re really sensitive, invest in a mask that is rated for protection from fumes. Though you live with these dangerous fumes every day as they off gas into your indoor environment, it is ideal to make sure that when you are promoting off gassing that you protect yourself.
Also, it is desirable to induce this off gassing with a Dry-Vapor cleaning system because less of these gasses stay in your furnishings and therefore cannot later contaminate your indoor air to the extent that they were able to previously.
One very simple thing you can do for your health is leave some windows open for a few hours every day. Perhaps you can pick the warmest hours of the day so as not to lose too much heat in the winter, or just leave a couple of windows open a crack and turn the heat off while you are away from the house during the day. Unless you live in an extremely polluted part of the world, creating ventilation is the simplest single step you can take toward improving indoor air quality.