(a) The Chairman shall appoint as members to advisory committees those persons selected by the Commissioners.

(b) The term of appointment to an advisory committee shall be for two years, unless otherwise specified by the Commission. To promote maximum participation, an advisory committee member may serve for only one consecutive full term. This subsection shall not be deemed to affect the term of appointment of any present member of an advisory committee in effect on the original effective date of this part, September 24, 1975.

(c) A vacancy that occurs during the term of an appointment normally will be filled by the Commission from the applications or nominations on file. Appointment to any such vacancy will be for the unexpired portion of the original appointment. Appointees to such an unexpired term may be reappointed for a full two-year term.

(d) Notwithstanding paragraphs (b) and (c) above, members of the Toxicological Advisory Board shall be appointed for terms of three years. Members may be reappointed for a subsequent three-year term. Any vacancy on the Board shall be filled in the same manner in which the original appointment was made. Any person appointed to fill a vacancy occurring before the expiration of the term for which his or her predecessor was appointed shall serve only for the remainder of such term.