Bioconcentration of Perfluorinated Alkyl Acids: How Important Is Specific Binding?

• Published in: Environmental science & technology Vol. 47; no. 13; pp. 7214 - 7223
• Main Authors: Ng, Carla A, Hungerbühler, Konrad
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 02.07.2013
• Subjects: absorption; Adipose Tissue - metabolism; Agnatha. Pisces; Alkanesulfonic Acids - blood; Alkanesulfonic Acids - pharmacokinetics; Alkanesulfonic Acids - urine; Animal behavior; Animal, plant and microbial ecology; Animals; Applied ecology; bioaccumulation; Biological and medical sciences; Carps - metabolism; Cyprinus carpio; data collection; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; Extracellular Fluid - metabolism; fatty acid-binding proteins; Fatty Acid-Binding Proteins - metabolism; Fish; Fluorocarbons - blood; Fluorocarbons - pharmacokinetics; Fluorocarbons - urine; Freshwater; Fundamental and applied biological sciences. Psychology; gills; Kidney - metabolism; liver; Liver - metabolism; mammals; Mathematical models; mechanistic models; Models, Biological; Muscles - metabolism; Oncorhynchus mykiss; Oncorhynchus mykiss - metabolism; Pharmacokinetics; Pharmacology; Pollutants; prediction; Protein Binding; Proteins; serum albumin; Serum Albumin - metabolism; sulfonates; Tissue Distribution; transporters; Toxicokinetics; Binding protein; Vertebrata; Biological fixation; Organic perhalocompound; Pollutant behavior; Pisces; Organic fluorine compounds; Fluorine Organic compounds; Biological accumulation; Organic compounds
• ISSN: 0013-936X; 1520-5851; 1520-5851
• DOI: 10.1021/es400981a

Perfluorinated alkyl acids (PFAAs) are important global pollutants with unique pharmacokinetics. Evidence is accumulating that their behavior within organisms is affected by interaction with a number of proteins. In mammals, serum albumin, fatty acid binding proteins (FABPs) and organic anion transporters (OATs) have been identified as important to the tissue distribution, species-specific accumulation, and species- and gender-specific elimination rates of perfluoroalkyl carboxylates and perfluoroalkane sulfonates. Similar pharmacokinetics has been identified in fish. Yet, no mechanistic model exists for the bioaccumulation of PFAAs in fish that explicitly considers protein interactions. In this work, we present the first mechanistic protein-binding bioconcentration model for PFAAs in fish. Our model considers PFAA uptake via passive diffusion at the gills, association with serum albumin in the circulatory and extracellular spaces, association with FABP in the liver, and renal elimination and reabsorption facilitated by OAT proteins. The model is evaluated using measured bioconcentration and tissue distribution data collected in two previous studies of rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio). Comparing our model with previous attempts to describe PFAA bioconcentration using a nonspecific (partitioning-type) approach shows that inclusion of protein interactions is key to accurately predicting tissue-specific PFAA distribution and bioconcentration.