# Leachability and Chemical Profiles of Per- and Polyfluoroalkyl Substances in Electronic Waste Components: Targeted and Non-Targeted Analysis

## TL;DR

This study examines how much harmful fluorinated chemicals can leach from electronic waste components, finding that phone screens and plastics are the biggest sources.

## Contribution

The study provides new insights into PFAS leachability and chemical profiles in e-waste using both targeted and non-targeted analysis.

## Key findings

- Phone screens and plastics had the highest leachable PFAS levels, up to 1932 ng·kg−1.
- Capacitors and batteries showed mixed sulfonate/carboxylate PFAS patterns.
- Non-targeted analysis confirmed CF2/CF2O homologous trends in PFAS profiles.

## Abstract

Electronic waste (e-waste) is a growing solid waste stream with largely undisclosed and poorly characterized fluorinated constituents. We evaluated per- and polyfluoroalkyl substances (PFAS) leachability from four e-waste components (phone screens, phone plastics, capacitors, and Lithium-ion batteries) using a 30-day deionized water leaching test. PFAS were extracted by solid-phase extraction using weak anion exchange (WAX) cartridges and analyzed with a liquid chromatography triple-quadrupole mass spectrometer. In addition, the PFAS chemical profiles of e-waste components were characterized by non-targeted analysis. Leachable sums of detected PFAS (∑PFAS) were highest in phone screens (1739–1932 ng·kg−1) and phone plastics (1575–2197 ng·kg−1) and an order of magnitude lower in Lithium-ion batteries (148–158 ng·kg−1) and capacitors (147–243 ng·kg−1). Short-chain perfluoroalkyl acids (PFAAs) (e.g., PFBA, PFHxA) and legacy acids (e.g., PFOA, PFNA) were more prevalent in phone screens/plastics, whereas capacitors and batteries showed mixed sulfonate/carboxylate patterns (PFOS, PFHxS, and 6:2 FTS). Although capacitors and Lithium-ion batteries contained essential PFAS with high hazard potential at trace levels, phone screens and phone plastics pose a greater risk per mass due to higher ∑PFAS levels and larger volumes. Non-targeted analysis using Orbitrap Astral revealed CF2/CF2O homologous trends (confidence levels 2–3) with corroborating targeted findings. These findings highlight the need for PFAS-free alternatives, the disclosure of fluorinated additives, and stronger end-of-life management strategies to prevent PFAS releases from e-waste.