Is mold in shower toxic?

Homeowner concerned about black spots on ceiling

Learn the New Luxury Playbook at Luxury Connect | October 18-19 at the Beverly Hills Hotel

Dear Barry, I'm selling my home and am concerned about black spots on the ceiling of my stall shower. Could this be mold? If so, what could be the cause, and could this mold be the toxic kind? –Betty Dear Betty, As reported in numerous articles, mold infestation has become the leading environmental concern involving indoor air pollution. Mold typically occurs where materials are exposed to a continuous moisture source or where lack of ventilation promotes prolonged moisture conditions. In all likelihood, the black spots on your shower ceiling consist of mold – probably the result of inadequate venting of your bathroom. Required ventilation consists of an openable window or an exhaust fan. Even when these means of venting are provided, some bathroom windows are too small, some exhaust fans provide insufficient air flow, and some fans, although adequately sized, are simply unplugged. In bathrooms where adequate means of venting are installed, windows may remain clo...