The extraction of microplastics from complex environmental matrices, such as sewage sludge, has proven challenging because of their high organic content. A common procedure for the extraction of microplastics from sludge involves conducting a chemical digestion to reduce the amount of organic matter in the sample, followed by a density separation of microplastics. In order to increase the reliability of the density-based separation, an optimisation of the chemical digestion is needed. The aim of this study was to maximise the total solids and carbon content reduction of sludge by optimising the sodium dodecyl sulphate (SDS) pretreatment and the duration of HO digestion. A reduction in total solids by 95.6% and in carbon content by 98.1% were achieved with the optimised digestion method, which involved an application of 1% SDS and a 2-day HO treatment in the first digestion step. The inclusion of the SDS pretreatment significantly increased the reduction of total solids and carbon content. The optimised digestion process had no significant visible effects on tested reference microplastics and provided an extraction efficiency of 84% for 150 μm reference microspheres and 72% for 650 μm long microfibres. To enable the application of the optimised digestion process to other types of sludges, the consumption of SDS and HO were also presented as per grams of organic matter in the untreated sludge.
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http://dx.doi.org/10.1016/j.scitotenv.2022.154777 | DOI Listing |
Environ Sci Process Impacts
January 2025
Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, Parsons Laboratory, 15 Vassar Street, Cambridge, Massachusetts 02139, USA.
The high salinity and organic content in oil and gas wastewaters can cause ion suppression during liquid chromatography mass spectrometry (LC/MS) analysis, diminishing the sensitivity and accuracy of measurements in available methods. This suppression is severe for low molecular weight organic compounds such as ethanolamines (, monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), -methyldiethanolamine (MDEA), and ,-ethyldiethanolamine (EDEA)). Here, we deployed solid phase extraction (SPE), mixed-mode LC, triple quadrupole MS with positive electrospray ionization (ESI), and a suite of stable isotope standards (, one per target compound) to correct for ion suppression by salts and organic matter, SPE losses, and instrument variability.
View Article and Find Full Text PDFJ Mass Spectrom
February 2025
FTMS Laboratory for Human Health Research, Department of Chemistry, North Carolina State University, Raleigh, North Carolina, USA.
Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a class of emerging contaminants that have been in use industrially since the 1940s. Their long-term and extensive commercial use has led to their ubiquitous presence in the environment. The ability to measure the bioconcentration and distribution of PFAS in the tissue of aquatic organisms helps elucidate the persistence of PFAS as well as environmental impacts.
View Article and Find Full Text PDFCochrane Database Syst Rev
January 2025
Cochrane Kidney and Transplant, Centre for Kidney Research, The Children's Hospital at Westmead, Westmead, Australia.
Background: Cytomegalovirus (CMV) is a significant cause of morbidity and death in solid organ transplant recipients. Pre-emptive treatment of patients with CMV viraemia using antiviral agents has been suggested as an alternative to routine prophylaxis to prevent CMV disease. This is an update of a Cochrane review first published in 2006 and updated in 2013.
View Article and Find Full Text PDFInorg Chem
January 2025
State Key Laboratory of Molecular & Process Engineering, SINOPEC Research Institute of Petroleum Processing, Beijing 100083, China.
The ZSM-5 zeolite is the key active component in high-severity fluid catalytic cracking (FCC) catalysts and is routinely activated by phosphorus compounds in industrial production. To date, however, the detailed structure and function of the introduced phosphorus still remain ambiguous, which hampers the rational design of highly efficient catalysts. In this work, using advanced solid-state NMR techniques, we have quantitatively identified a total of seven types of P-containing complexes in P-modified ZSM-5 zeolite and clearly revealed their structure, location, and catalytic role.
View Article and Find Full Text PDFEmergencias
December 2024
Servicio de Análisis Clínicos, Hospital Universitario Santa Lucía, Cartagena, Murcia, España.
Objective: To analyze the usefulness of mean mid-regional pro-adrenomedullin (MR-proADM) level to stratify risk in emergency department patients with solid tumors attended for febrile neutropenia after chemotherapy. To compare risk prediction with MR-proADM to that of conventional biomarkers and scores on the Multinational Association for Supportive Care in Cancer (MASCC) score.
Methods: Prospective observational cohort study enrolling patients with solid tumors who developed febrile neutropenia after chemotherapy.
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