To obtain a compsn. which, when thermally decomposed, emits volatile org. compds. in reduced amts. into the air by compounding activated carbon or activated graphite as an additive into a charcoal briquette compsn.

This compsn. is a combustible carbon substance and contains 65-99.9wt % (dry wt. basis) combustible carbonaceous substance and 0.1-20wt.% activated carbon substance selected from among activated carbon, activated graphite, and their mixture. The activated carbon substance may be formed in-site during the thermal decomposition of the compsn. by compounding a finely ground humin-contg. mineral together with a carbon substance selected from among carbon, graphite, and their mixture into the compsn. The carbon substance pref. has a volatile org. compd. content of 10mg/g at 982.2° and 760mmHg.