You can imagine my surprise when I found out that the chlorine that is used to disinfect many swimming pools and most public water supplies can cause an unsafe level of chlorine inhalation. I suffered from asthma symptoms for years growing up and in the summer time spent hours at the neighborhood pool.
Exposure to chlorine is not in itself that dangerous, but if you already suffer form allergies or asthma it certainly can aggravate your symptoms. Studies are also being conducted that indicate that prolonged exposure to chlorine can lead to an increased risk of developing asthma in children. One of the primary sources of chlorine exposure actually comes from showering as most water utilities use chlorine to disinfect water to remove harmful bacteria.
While it is virtually impossible to avoid contact with chlorine, it is a good idea to limit your exposure to it, especially if you already have allergy symptoms or asthma. Almost any water filter with a carbon based media will reduce the chlorine content in your water.