Location: Animal Metabolism-Agricultural Chemicals ResearchTitle: Perfluoroalkyl substance (PFAS) concentrations in plasma and skin of dairy cattle after life-time exposures to contaminated water and feed: Associated trends with age and lactation
|SCHOLLJEGERDS, ERIC - New Mexico State University|
|IVEY, SHANNA - New Mexico State University|
|ESTEBAN, EMILIO - Food Safety Inspection Service (FSIS)|
|JOHNSTON, JOHN - Food Safety Inspection Service (FSIS)|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/16/2022
Publication Date: 6/15/2022
Citation: Lupton, S.J., Smith, D.J., Scholljegerds, E., Ivey, S., Snyder, A.W., Esteban, E., Johnston, J.J. 2022. Perfluoroalkyl substance (PFAS) concentrations in plasma and skin of dairy cattle after life-time exposures to contaminated water and feed: Associated trends with age and lactation. 3rd National PFAS Meeting. Abstract.
Technical Abstract: A US herd of approximately 5,000 dairy cattle was discovered to have life-time exposures to feed and water contaminated with perfluoroalkyl substances (PFAS) originating from the legacy use of aqueous film forming foam (AFFF). Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) were the major PFAS compounds in water sources; however, perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorononanoic acid (PFNA), perfluoro butane sulfonate (PFBS), perfluoro hexane sulfonate (PFHxS), and perfluoro heptane sulfonate (PFHpS) were also present in water and analyzed for the study. On-farm plasma and skin (ear notch) samples were taken from a cohort of 164 dairy cattle ranging in age from < 6 months to ~7-8 years old. The cohort included heifers, lactating cows, and dry cows. Dairy heifers ranging in age from < 6 months to 12-14 months had plasma concentrations of summed PFAS carboxylic acids averaging 0.6 ± 0.6 ng/mL (mean ± SD); the summed sulfonate concentration in the same cohort averaged 105.3 ± 35.3 ng/mL. Sulfonate concentrations trended upward with age of heifer. Lactating and dry cows ranged from 2 to 8 years old with summed carboxylic acid concentrations in plasma of dry cows averaging 0.3 ± 0.3 ng/mL while lactating cows averaged 1.5 ± 0.9 ng/mL. Summed sulfonate concentrations in plasma of dry cows were 170.7 ± 54.1 ng/mL while the lactating cows averaged 197.3 ± 76.0 ng/mL. Overall, PFHxS, PFHpS, and PFOS were present in the highest concentrations in plasma. Generally, the PFHxS concentrations in plasma for heifers, lactating cows, and dry cows were higher than the average PFOS concentration in those cohort groups. In ear notch samples, PFHxS, PFHpS, and PFOS were the dominant PFAS’ present, however, the average PFOS concentration was generally higher than that of PFHxS. The concentrations of PFHpS and PFOS in ear notches of heifers tended to accumulate with the age, however a significant (P < 0.05) effect of lactation status (dry vs lactating) on total sulfonate concentration in skin was noted where dry cows had higher concentrations than lactating cows. These data support the concept that PFAS tissue depots occur and that tissue depots may serve as releasable reservoirs of PFAS. On a population basis, summed PFAS concentrations in plasma averaged 160.8 ± 63.5 ng/mL across all 164 animals at the time of sampling. Analysis of all samples against estimated age, suggests that steady state of summed PFAS sulfonates occurred after about 2 years of exposure.