Computational estimates of daily aggregate exposure to PFOA/PFOS from 2011 to 2017 using a basic intake model

Area of Science:

• Environmental Science
• Toxicology
• Public Health

Background:

• Human exposure to per- and polyfluoroalkyl substances (PFAS) has been previously modeled to estimate serum concentrations.
• Production and use of PFAS, particularly PFOA and PFOS, have decreased.
• Recent concentration data from the US and other industrialized nations have become available.

Purpose of the Study:

• To estimate aggregate median intakes of PFOA and PFOS using more recent data.
• To update human exposure models for these persistent chemicals.

Main Methods:

• Collected and averaged summary statistics from secondary sources for PFOA and PFOS in various media (air, water, dust, soil).
• Mapped exposure data for adults and children.
• Utilized European dietary intake estimates for food consumption.
• Employed a first-order pharmacokinetic model.

Main Results:

• Estimated daily intake for adults: 40 ng/day PFOA and 40 ng/day PFOS.
• Estimated daily intake for children: 14 ng/day PFOA and 17 ng/day PFOS.
• These estimates are substantially lower than previously reported values, reflecting decreased environmental concentrations.

Conclusions:

• Updated intake estimates align with observed declines in PFOA/PFOS serum concentrations over the past decade.
• The enhanced estimation approach is supported by concomitant blood concentration data.
• This study provides a more accurate reflection of current human exposure levels to PFOA and PFOS.