Deciphering the synergistic effects of photolysis and biofiltration to actuate elimination of estrogens in natural water matrix

Water Res. 2024 Feb 1:249:120976. doi: 10.1016/j.watres.2023.120976. Epub 2023 Dec 5.

Abstract

The presence of estrogens in water environments has raised concerns for human health and ecosystems balance. These substances possess potent estrogenic properties, causing severe disruptions in endocrine systems and leading to reproductive and developmental problems. Unfortunately, conventional treatment methods struggle to effectively remove estrogens and mitigate their effects, necessitating technological innovation. This study investigates the effectiveness of a novel sequential photolysis-granular activated carbon (GAC) sandwich biofiltration (GSBF) system in removing estrogens (E1, E2, E3, and EE2) and improving general water quality parameters. The results indicate that combining photolysis pre-treatment with GSBF consistently achieved satisfactory performance in terms of turbidity, dissolved organic carbon (DOC), UV254, and microbial reduction, with over 77.5 %, 80.2 %, 89.7 %, and 92 % reduction, respectively. Furthermore, this approach effectively controlled the growth of microbial biomass under UV irradiation, preventing excessive head loss. To assess estrogen removal, liquid chromatography-tandem mass spectrometry (LC-MS) measured their concentrations, while bioassays determined estrogenicity. The findings demonstrate that GSBF systems, with and without photolysis installation, achieved over 96.2 % removal for estrogens when the spike concentration of each targeted compound was 10 µg L-1, successfully reducing estrogenicity (EA/EA0) to levels below 0.05. Additionally, the study evaluated the impact of different thicknesses of GAC layer filling (8 cm, 16 cm, and 24 cm) and found no significant difference (p>0.05) in estrogen and estrogenicity removal among them.

Keywords: Adsorption; Biodegradation; Estrogenicity; Photodegradation.

MeSH terms

  • Charcoal
  • Ecosystem
  • Estrogens* / chemistry
  • Estrone
  • Humans
  • Photolysis
  • Water Pollutants, Chemical* / chemistry

Substances

  • Estrogens
  • Water Pollutants, Chemical
  • Estrone
  • Charcoal