The remediation of di-(2-ethylhexyl) phthalate-contaminated sediments by water hyacinth biochar activation of calcium peroxide and its effect on cytotoxicity

Environ Res. 2023 Jan 1;216(Pt 3):114656. doi: 10.1016/j.envres.2022.114656. Epub 2022 Oct 29.

Abstract

The presence of di-(2-ethylhexyl) phthalate (DEHP) in the aquatic systems, specifically marine sediments has attracted considerable attention worldwide, as it enters the food chain and adversely affects the aquatic environment and subsequently human health. This study reports an efficient carbocatalytic activation of calcium peroxide (CP) using water hyacinth biochar (WHBC) toward the efficient remediation of DEHP-contaminated sediments and offer insights into biochar-mediated cellular cytotoxicity, using a combination of chemical and bioanalytical methods. The pyrolysis temperature (300-900 °C) for WHBC preparation significantly controlled catalytic capacity. Under the experimental conditions studied, the carbocatalyst exhibited 94% of DEHP removal. Singlet oxygen (1O2), the major active species in the WHBC/CP system and electron-rich carbonyl functional groups of carbocatalyst, played crucial roles in the non-radical activation of CP. Furthermore, cellular toxicity evaluation indicated lower cytotoxicity in hepatocarcinoma cells (HepG2) after exposure to WHBC (25-1000 μg mL-1) for 24 h and that WHBC induced cell cycle arrest at the G2/M phase. Findings clearly indicated the feasibility of the WHBC/CP process for the restoration of contaminated sediment and contributing to understanding the mechanisms of cytotoxic effects and apoptotic of carbocatalyst on HepG2.

Keywords: Activated calcium peroxide; Advanced oxidation; Cytotoxicity; Di-(2-ethylhexyl) phthalate; Marine sediments; Water hyacinth biochar.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Diethylhexyl Phthalate* / toxicity
  • Eichhornia* / metabolism
  • Humans
  • Phthalic Acids*
  • Water Pollutants, Chemical* / toxicity

Substances

  • biochar
  • phthalic acid
  • Diethylhexyl Phthalate
  • calcium peroxide
  • Water Pollutants, Chemical
  • Phthalic Acids