Evidence map›Paper›PMID 41957102›Full record

ArticleScientific reports2026

Efficacy and limitations of the A2O process in simultaneous removal of surfactants and nutrients from municipal wastewater.

Tahereh Zarei Mahmoudabadi, Fahimeh Teimouri, Amir Hossein Bagheri, Sara Jambarsang

Abstract read
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Article in Scientific reports, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors.

Tahereh Zarei MahmoudabadiStudent Research Committee, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Fahimeh TeimouriEnvironmental Sciences and Technology Research Center, Department of Environmental Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. f.teimouri1401@gmail.com.
Amir Hossein BagheriStudent Research Committee, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Sara JambarsangCenter for Healthcare Data Modeling, Department of Biostatistics and Epidemiology, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

This study evaluated the efficacy of the Anaerobic-Anoxic-Oxic (A2O) process for the simultaneous removal of organic pollutants, specifically surfactants (detergents), and nutrients (nitrogen and phosphorus) from municipal wastewater. Sampling was conducted over a 12-month period from September 23, 2023 to September 22, 2024, at a monthly frequency. During each sampling event, grab samples were collected from multiple points within the treatment train: the raw influent wastewater, the influent and effluent streams of the anaerobic, anoxic, and aerobic tanks, and the final effluent from the secondary clarifier. The anionic surfactants (as methylene blue active substances, MBAS), ammonium-nitrogen (NH₄⁺-N), nitrate-nitrogen (NO₃⁻-N), nitrite-nitrogen (NO₂⁻-N), and total phosphorus (TP)—were quantified in accordance with Standard Methods for the Examination of Water and Wastewater. The mean final effluent concentrations were 0.22 ± 0.05 mg/L for linear alkylbenzene sulfonate (LAS), 13.18 ± 3.7 mg/L for nitrate (as NO₃-N), and 4.46 ± 0.18 mg/L for phosphorus (as P). Process performance data indicated that the oxic tank was the primary site for LAS and phosphorus removal, while the anoxic tank facilitated the most significant nitrate reduction. While the Anaerobic-Anoxic-Oxic (A2O) process proficiently removes surfactants and phosphorus via microbial metabolism, its performance in nitrate elimination is constrained. Inadequate denitrification in the anoxic stage, frequently due to a limited biodegradable carbon source or improper redox conditions, indicates a need for process optimization.

Indexed as

PhosphorusSurface-Active AgentsWaste Disposal, FluidWastewaterWater Pollutants, ChemicalWater PurificationAnaerobiosisNitratesNitrogenNitratesNitrogenPhosphorusSurface-Active AgentsWastewaterWater Pollutants, ChemicalBiological processNutrientsSurfactantsWastewater treatment

Identifiers

PMID41957102
PMCPMC13201829

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.