The use of an algal bioindicator in the assessment of different chemical remediation strategies for PAH-contaminated soils and sediments

ROTONDO L; MORA V; TEMPORETTI P; BEAMUD G.; PEDROZO, F.L.

Journal of Environmental Chemical Engineering

Science Direct

Año: 2023 vol. 11

2213-2929

Polycyclicaromatic hydrocarbons (PAHs) are ubiquitous petroleum-derived pollutants thattend to accumulate in soils and sediments. Among the in situ chemical oxidationtechnologies applied at PAH-contaminated sites are Fenton reagent (FN),persulfate ion (PS) and permanganate ion (PM). The natural phytoplankton of anaquatic environment is useful as a biological indicator of the treatmentefficacy of pollutant degradation. The objective of this work was to assess theuse of an algal species, native from Los Barreales Reservoir (Argentina), as anefficacy indicator of the chemical remediation of PAH-contaminated soils andsediments. Oxidations with FN, PS or PM were carried out on soils and sedimentspreviously contaminated with two types of PAHs (phenanthrene (Ph) or Benzo(a)anthracene(Ba)), analysing pH, residual oxidant, PAH degradation and heterotrophicbacteria abundance in soils or sediments after 7 days. Then, a bioassay wascarried out by incubating the obtained soils or sediments, and the native algaScenedesmus quadricauda (Turpin, Br´ebisson), analysing its abundance after 7 days.S. quadricauda abundance was related to PAH degradation efficacy, residualoxidants and changes in system pH. In this sense, the application of PSproduced the lowest growth of the indicator in assays both with soils andsediments. Fenton reaction results varied depending on the contaminating PAH,with the best percentages of PAH degradation and growth of S. quadricauda forBa. PM oxidation resulted in the best development of the indicator. This studyconstitutes a first approach to the use of S. quadricauda as an efficiencyindicator of soil/sediment chemical remediation.