(b) The proficient laboratory, including a manufacturer’s in-house laboratory, that analyzes the bulk prenatal multivitamin product or packaged prenatal multivitamin product for heavy metals shall meet all of the following criteria:

1. (1)

   1. (A) Be accredited under the standards of the International Organization for Standardization’s (ISO) and the International Electrotechnical Commission’s (IEC) ISO/IEC 17025:2017 international standard regarding the general requirements for the competence of testing and calibration laboratories as they pertain to the testing of heavy metals.
   2. (B) To the extent such standards contradict the requirements of any federal regulations promulgated pursuant to the Federal Food, Drug, and Cosmetic Act pertinent to supplements, the federal regulations shall control.
2. (2) Use an analytical method that is at least as sensitive and specific as that described in Section 4.7 of the United States Food and Drug Administration’s Elemental Analysis Manual for Food and Related Products: Inductively Coupled Plasma-Mass Spectrometric Determination of Arsenic, Cadmium, Chromium, Lead, Mercury, and Other Elements in Food Using Microwave Assisted Digestion.
3. (3) Demonstrate proficiency in quantifying each heavy metal to 10 micrograms or less of the heavy metal to kilogram of supplement (μg/kg) through an independent proficiency test. Proficiency means that a laboratory achieves a z-score that is less than, or equal to, plus or minus two (≤ ±2).