Complex sentence: There has been some debate as to whether or not the filters for these masks contain asbestos they do not contain asbestos but they do contain activated charcoal, which might be inhaled by the wearer if the cotton seals inside the filter are damaged.
Split into simpler sentences: There has been some debate as to whether or not the filters for these masks contain asbestos. They do not contain asbestos, but they do contain activated charcoal, which might be inhaled by the wearer if the cotton seals inside the filter are damaged.