# Per- and polyfluoroalkyl substances (PFAS) in fish collected from the Rio Grande and reservoirs in northern New Mexico

## TL;DR

This study measures PFAS chemicals in fish from northern New Mexico's rivers and reservoirs, finding higher concentrations in liver tissues and evidence of biomagnification.

## Contribution

The study provides new data on PFAS concentrations in fish from under-sampled desert southwest ecosystems and identifies biomagnification patterns.

## Key findings

- PFAS compounds were detected in most fish tissues, with PFOS concentrations in liver samples up to 350 times higher than in muscle samples.
- Average tissue concentrations of PFAS were calculated to be 2.02 ± 1.81 ng g-1.
- Higher δ15N values correlated with increased perfluorodecanoic acid concentrations, indicating trophic-level influences.

## Abstract

Per- and polyfluoroalkyl substances (PFAS) are a group of industrial and commercial chemicals widely used throughout the world due to their beneficial chemical properties. Because of their widespread use, their chemical stability, and their ability to be transported over long distances through atmospheric deposition and movement through waterways, PFAS are found throughout most aquatic ecosystems; yet large sampling gaps exist among reservoir and river ecosystems in the desert southwest of the United States. In this study, we examine PFAS concentrations in the tissue of fish (catfish [channel and blue], common carp, smallmouth bass, northern pike, walleye, white crappie and white sucker) collected in northern New Mexico, including examining PFAS composition and concentration relative to trophic level distribution. We collected fish from two man-made reservoirs and from the Rio Grande. We then collected muscle and liver tissues from fish specimens, which were screened for 39 PFAS compounds. We detected PFAS compounds in most fish tissue sampled, including the biomagnification of PFAS compounds within liver samples, with PFOS concentrations ranged from 1.13 to 350.1 (64.4 average) times higher in the liver samples compared to muscle samples. Most PFAS concentrations within muscle samples were within the range of atmospheric transportation previously reported and average tissue concentrations of PFAS were calculated to be 2.02 ± 1.81 ng g-1. Using stable isotopes as a predictor of trophic-foraging exposure and PFAS concentrations, we noted a correlation between enriched δ15N values, which had higher perfluorodecanoic acid concentrations.