Section 6. The department of public health may, by rule, establish such exemptions as may be necessary to facilitate the sale of any accumulated or unsold stocks of wholesome bakery products, and in other cases consistent with sections two to six, inclusive, and section nine I. The standards and requirements prescribed by sections two to six, inclusive, shall conform to rules and regulations adopted by the department of public health, and said sections and rules and regulations shall be enforced by said department and by local boards of health acting under the supervision of said department.