Near each coal mining area in India is a residential block for employees. A study conducted on air quality around the Singarani coal field in Andhra Pradesh reveals unacceptably high levels of heavy metals. These lead to a host of diseases and ailments. Traces of these metals, some of them toxic, hitch a free ride on the very fine, respirable dust particles which abound in mining areas. These can penetrate deep into the respiratory tract, entering the body. The study questions situating residential complexes near mining areas to avoid danger to human health.