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Page 2 of 13 Bogdan et al. J Environ Expo Assess 2024;3:14 https://dx.doi.org/10.20517/jeea.2024.08

infant scenarios to the Minnesota Department of Health’s 2024 PFOS reference serum concentration (2.6 ng/mL)
concludes that PFAS from powdered formula likely does not pose a significant risk to infants.

Keywords: Infant formula, baby formula, PFAS, per- and polyfluoroalkyl substances, PFOS, toxicokinetics,
childhood exposure, breastmilk

INTRODUCTION
Per- and polyfluoroalkyl substances (PFAS) are a family of approximately 15,000 synthetic chemicals that
[1]
comprise at least one fluorine atom attached to a linear or branched alkyl chain . This molecular structure
results in their stability and resistance to biodegradation . PFAS have been manufactured since the 1950s
[2]
and are found in products such as stain-resistant and water-repellant products, food packaging, nonstick
cookware, some personal care products and cosmetics, and some lubricants, paints and sealants . Due to
[3]
chemical releases to the soil, air, and water by manufacturers and decades of use of products containing
PFAS by the public, PFAS are now ubiquitous in the environment, and human exposure can occur from
numerous sources.

The Centers for Disease Control and Prevention’s (CDC) National Health and Nutrition Examination
Survey (NHANES) has measured 12 PFAS in blood serum in samples dating back to 1999, and four PFAS
have been detected consistently in nearly all of the people tested: perfluorooctane sulfonic acid (PFOS),
perfluorooctanoic acid (PFOA), perfluorohexanesulfonic acid (PFHxS), and perfluorononanoic acid
[4]
[5-8]
(PFNA) . PFAS are also known to partition into breastmilk , reaching sufficient concentrations to result
in significant exposure to young infants [9-11]
The Minnesota Department of Health (MDH) makes health-based guidance for contaminants found in
groundwater (Minnesota Statute §103H.201). A health-based guidance value (HBGV) is the concentration
of contaminant in water that poses little to no health risk for those drinking the water , including highly
[12]
exposed or susceptible populations. HBGVs are derived solely on the basis of human health and do not
consider technical feasibility or cost of treatment. In 2002, MDH first developed HBGVs for PFOS and
[13]
PFOA . This guidance was based on extremely limited animal toxicity data. In the subsequent 20 years,
scientists have produced a more robust toxicity and toxicokinetic (TK) database for PFOS and PFOA that
now includes human epidemiology data. As a result, MDH guidance for PFOS and PFOA has undergone
many iterations based on the latest available science, resulting in progressively lower MDH HBGVs with
[13]
each update . MDH has also developed HBGVs for other PFAS including perfluorobutanesulfonic acid
(PFBS), perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), and PFHxS .
[14]
MDH’s policy is to protect the most vulnerable populations when deriving HBGVs , and for the long-
[12]
chain PFAS family members, the infant is the most sensitive population. Many PFAS have half-lives lasting
years in humans . Due to placental and breastmilk transfer, infants are among the most highly exposed
[2]
individuals [11,15-17] . While reevaluating the PFOA HBGV in 2017, MDH developed a model to better account
for the unique toxicokinetic behaviors of PFOA in humans, particularly pertaining to infant exposures. The
model received minor iterative updates since development, and it was subsequently used for deriving
HBGVs for PFOS (2017, 2019) and PFHxS (2019) [13,14] . The TK model recently received a major revision and
was used in the derivation of MDH’s 2024 epidemiology-based HBGVs for PFOA and PFOS [18,19] . The
revised model has been described in a recently accepted publication .
[20]