This function checks whether the CAS/CARN chemical identifier follows the anticipated format of XXXXXXX-YY-Z (i.e. 2-7 digits, 2 digits, and 1 digit, respectively).
cas_id_check(cas)
Logical output (TRUE or FALSE) indicating whether the character string(s) provided match the anticipated format for a CAS/CASRN chemical identifier.
A character string, or vector of character strings, indicating CAS/CASRN number.