2025
A longitudinal study of mass loads of quaternary ammonium compounds in sludge associated with COVID-19 Stringency Index indicators in Beijing, China
Thapa B, Sapkota S, Chen J, Zunong J, Asihaer Y, Khattab N, Li M, Ding D, Vermund S, Shu M, Hu Y. A longitudinal study of mass loads of quaternary ammonium compounds in sludge associated with COVID-19 Stringency Index indicators in Beijing, China. Environmental Chemistry And Ecotoxicology 2025, 7: 39-49. DOI: 10.1016/j.enceco.2024.10.004.Peer-Reviewed Original ResearchDialkyldimethylammonium chlorideWastewater treatment plantsTreatment plantsContainment policiesQuaternary ammonium compoundsSludge specimensChromatography-tandem mass spectrometryCOVID-19 containment policiesLiquid chromatography-tandem mass spectrometryWorkplace closuresSBACSludgeBackward estimationIncreasing trendQuaternary ammonium compounds' concentration
2024
Longitudinal mass loads of phthalate esters in sewage sludge and their association with public health and social measures for COVID-19 control in Beijing
Sapkota S, Thapa B, Chen J, Zunong J, Asihaer Y, Li M, Ji X, Ding D, Li H, Ma B, Vermund S, Shu M, Hu Y. Longitudinal mass loads of phthalate esters in sewage sludge and their association with public health and social measures for COVID-19 control in Beijing. Ecotoxicology And Environmental Safety 2024, 282: 116756. PMID: 39029222, DOI: 10.1016/j.ecoenv.2024.116756.Peer-Reviewed Original ResearchPopulation-normalized mass loadsPhthalate estersExposure to environmental contaminantsSewage sludge samplesBis(2-ethylhexyl) phthalateMunicipal wastewater treatment plantWastewater treatment plantsSewage sludgeEnvironmental contaminationSludge samplesTreatment plantsBis(2-ethylhexylPeak concentrationsPhthalateSewagePublic healthDEHPGC/MS analysisMPAEsMass loadingExpanding body of literatureConcentrationMono(2-ethyl-5-oxohexyl) phthalate