How eartworms Eisenia andrei interact with sewage sludge-derived biochar

Authors

  • Vladimír Frišták Department of Chemistry, Trnava university in Trnava
  • Diana Bošanská
  • Jana Fančovičová
  • Martin Pipíška
  • Christoph Pfeifer
  • Gerhard Soja

DOI:

https://doi.org/10.34135/nbc.2027

Keywords:

sewage sludge, biochar, pyrolysis, Earthworms, heavy metal, organic pollutants

Abstract

Pyrolysis of sewage sludge is emerging as a promising method for treating this heterogeneous and highly complex waste with increasing research work. One of the main constraints on the use of sludge-derived biochar as a soil additive are its heterogeneous properties and content of organic and inorganic contaminants. The main objective of our work was to carry out a basic physicochemical characterization of biochar prepared from municipal WWTP sewage sludge (PSM) at 603-615°C by pH, EC, CHN-S analysis, total concentrations of metals and metalloids (As, Cd, Cr, Cu, Ni, Pb, Zn, Fe and Hg), determination of the presence of polycyclic aromatic hydrocarbons (18-PAHs), polychlorinated dibenzo-p-dioxins and dibenzofurans (17-PCDD/Fs) and polychlorinated biphenyls (7-PCBs). The PCM material was tested by short-term avoidance test and long-term cultivation test with earthworms Eisenia andrei. Elemental analysis revealed the concentrations of heavy metals in PSM: Fe (138 g/kg), Zn (2602 mg/kg), Cu (582 mg/kg), Cr (107 mg/kg), Pb (87 mg/kg), Ni (67 mg/kg), As (<1 mg/kg), Hg (<2 mg/kg), Cd (<1 mg/kg). Total extractable concentrations of 17-PCDD/Fs in PSM were lower than quantification limits applied for analysis. Concentration of 7-PCBs in PSM were in case of all studied structures (PCB28, PCB52, PCB101, PCB118, PCB138, PCB153, PCB180) under limit of quantification. There was no relevant evidence of a negative impact of PSM on the behaviour of soil earthworms in avoidance test. PSM did not cause physiological or biochemical stress to earthworms in long-term cultivation test because of higher reproduction activity. 10% PSM amendment caused more than 3-fold higher concentration of bioaccumulated Fe in tissues of Eisenia andrei compared to the value of Fe concentration in the control exposure. Higher concentrations in earthworm tissues cultured in PSM medium were also observed for Cr and Zn. Differences in concentrations of accumulated Cd, Cu, Ni, Pb in earthworms from PSM medium were not statistically significant compared to control. Demonstrating unequivocally the effect of PSM on earthworm behaviour and response requires a longer-term test, as well as a test that reflects realistic environmental conditions where natural aging of pyrolysis materials occurs.

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Published

2024-12-29

How to Cite

Frišták, V., Bošanská, D., Fančovičová, J., Pipíška, M., Pfeifer, C., & Soja, G. (2024). How eartworms Eisenia andrei interact with sewage sludge-derived biochar. Nova Biotechnologica Et Chimica, 23(3), e2027. https://doi.org/10.34135/nbc.2027

Issue

Section

Research Articles