Efficiency of Bacillus thuringiensis biofilters on 17β-estradiol removal

Amanda Gonçalves Kieling,Graziela Tais Schmitt,Marcelo Oliveira Caetano

doi:10.22571/2526-4338295

Amanda Gonçalves Kieling, Graziela Tais Schmitt + Show 1 more

Open Access

https://doi.org/10.22571/2526-4338295

Copy DOI

Abstract

This study evaluated the potential of Bacillus thuringiensis biofilters and natural substrates for removal of the natural estrogen 17β-estradiol (E2) in aqueous solutions. Filters biologically activated with this bacterium and containing rice husk ash (RHA) or activated carbon (AC) were monitored for 20 days for biofilm formation. In all samples, E2 was quantified by SPE (solid phase extraction) and LC-MS/MS (liquid chromatography coupled to mass spectrometry). The results showed 83% removal for the biofilter containing RHA and 86% for AC, indicating the potential of the bacterium Bacillus thuringiensis to biodegrade E2. This study demonstrated that biofiltration can be a method used for E2 removal.

Highlights

The number of emerging contaminants and endocrine disruptors released into the aquatic environment is growing continuously and has been raising worldwide concerns, mainly due to the potential risks to human health and the environment
Rice husk ash (RHA) is a residue originating from the burning of rice husk, showing high resistance, insolubility in water, and a granular and porous structure, presenting itself as an adsorbent material (Ngah & Hanafiah, 2008). In view of these aspects, the present study evaluated the potential of Bacillus thuringiensis biofilters and adsorbent substrates for removal of the natural estrogen 17β-estradiol (E2) in aqueous solutions
A strain containing the bacterium Bacillus thuringiensis was provided by the Liberato Salzano Vieira da Cunha Technical School Foundation (LIBERATO), Novo Hamburgo city, Rio Grande do Sul State, Brazil, where it was kept in glycerol medium in an ultrafreezer at -80 °C

Summary

Introduction

The number of emerging contaminants and endocrine disruptors released into the aquatic environment is growing continuously and has been raising worldwide concerns, mainly due to the potential risks to human health and the environment These compounds comprise natural and synthetic hormones, pharmaceutical and personal care products, pesticides, illicit drugs, and other industrial chemicals (Campos, Queiroz, & Roston, 2019; Riva et al, 2018). There are three forms of natural estrogen (estrone, 17β-estradiol, and estriol), 17βestradiol or E2 has the highest biologically active estrogenic activity (Nazari & Suja, 2016) This type of estrogen is excreted through feces and urine (human and animal), is persistent in the environment, and can accumulate in soil, sediment, sludge, and along the food chain. Some studies have verified the presence of E2 in different environmental matrices in Brazil (Campanha et al, 2015; Montagner et al, 2019)

Methods

Results

Conclusion