Asbestos forces closure of two additional Philadelphia schools.

Two Philadelphia schools, Frankford High School and Mitchell Elementary School, are closing temporarily due to the presence of asbestos in their buildings. The discovery comes after asbestos was found earlier this year in two other district-owned and managed buildings that had "incomplete or inaccurate records." Asbestos, which was once commonly used in building materials for insulation and as a fire retardant, becomes a health concern when it is released into the air and can be inhaled. Nearly 300 buildings in the Philadelphia school district were constructed or repaired when asbestos was commonly used.