# Sorption of Polycyclic Aromatic Sulfur Heterocycles (PASH) on Nylon Microplastics at Environmentally Relevant Concentrations

## TL;DR

This paper studies how certain sulfur-containing pollutants attach to nylon microplastics in water, which could affect the environment and human health.

## Contribution

The study introduces a new analytical method and investigates sorption behavior of PASHs on nylon microplastics.

## Key findings

- An analytical method was developed for detecting PASHs at low environmental concentrations.
- Sorption kinetics of three benzo[b]naphthothiophene isomers on nylon microplastics were characterized.
- The findings could inform remediation strategies for contaminated aquatic ecosystems.

## Abstract

Microplastics have garnered an infamous reputation as a sorbate for many concerning environmental pollutants and as a delivery vehicle for the aquatic food chain through the ingestion of these contaminated small particulates. While sorption mechanisms have been extensively studied for polycyclic aromatic hydrocarbons, polycyclic aromatic sulfur heterocycles (PASHs) have not been investigated, partly due to their low concentrations in aquatic ecosystems. Herein, an analytical methodology is presented for the analysis of dibenzothiophene, benzo[b]naphtho[1,2-b]thiophene, benzo[b]naphtho[2,1-b]thiophene, benzo[b]naphtho[2,3-b]thiophene, chryseno[4,5-bcd]thiophene and dinaphtho[1,2-b:1′,2′-d]thiophene at relevant environmental concentrations based on solid phase extraction and high-performance liquid chromatography. The sorption uptake behavior and the sorption kinetics of the three benzo[b]napthothiophene isomers were then investigated on nylon microplastics to provide original information on their environmental fate and avoid human contamination through the food chain. The obtained information might also prove relevant to the development of successful remediation approaches for aquatic ecosystems.