Assessing Per- and Polyfluoroalkyl Substances in Fish Fillet Using Non-Targeted Analyses

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Ecotoxicology

Background:

• Per- and polyfluoroalkyl substances (PFAS) are persistent, man-made chemicals with widespread environmental presence.
• Human exposure to PFAS occurs through various pathways, with fish consumption being a significant route.
• Current fish monitoring for PFAS is limited, often targeting only a few compounds and primarily in heavily contaminated areas.

Purpose of the Study:

• To investigate the presence of PFAS in fish fillets from recreational and drinking water sources in central North Carolina.
• To determine if PFAS exist in fish that are not detectable by conventional targeted monitoring methods.
• To assess the levels of specific PFAS, including perfluorooctanesulfonic acid (PFOS), in fish fillets.

Main Methods:

• Utilized liquid chromatography, ion mobility spectrometry, and mass spectrometry (LC-IMS-MS) for comprehensive PFAS analysis.
• Employed suspect screening with an in-house library for identifying known PFAS.
• Conducted non-targeted data analyses to detect additional, previously unidentified PFAS features.
• Quantified perfluorooctanesulfonic acid (PFOS) concentrations in fish fillet samples.

Main Results:

• A total of 36 distinct PFAS compounds were detected in the analyzed fish fillets.
• Nineteen of the detected PFAS were not identifiable through common targeted monitoring approaches.
• Individual fish contained a minimum of 6 and a maximum of 22 different PFAS.
• Median PFOS levels in fish fillets were notably high, ranging from 11.6 to 42.3 ppb.
• No significant correlation was found between PFOS levels and the total number of PFAS detected per fish.

Conclusions:

• Standard PFAS monitoring methods in fish are insufficient, missing a significant number of contaminants.
• Fish from recreational and drinking water sources in central North Carolina harbor a diverse range of PFAS.
• Elevated PFOS levels suggest a concerning level of contamination in the studied fish populations.
• Future monitoring strategies should incorporate non-targeted analyses and expand the range of targeted PFAS to better assess environmental contamination and human exposure risks.