Occurrence of quaternary ammonium compounds (QACs) and their application as a tracer for sewage derived pollution in urban estuarine sediments

Biodegradation of benzalkonium chlorides singly and in mixtures by a Pseudomonas sp. isolated from returned activated sludge

“…A preliminary biodegradation experiment was conducted to find suitable concentrations for BDDA, BDTA and their mixture. BDDA or BDTA were not degraded after 14 days of incubation in pure medium when present at con- While the individual concentration of BACs in sewage sludge or sediment samples is typically less than 10 mg kg −1 [6], the total concentration of QACs can be up to 15 times higher [4].…”

“…QACs can therefore enter the aquatic environment via the suspended organic matter in wastewater effluent [4], and the terrestrial environment through the application of biosolids as a soil amendment for crop production [5]. Total concentrations ranging from 22 to 167 mg kg −1 have been measured for QACs in biosolids [4,6].…”

Quaternary ammonium compounds (QACs): A review on occurrence, fate and toxicity in the environment

“…The main sources of QACs released into the environment are the discharge of effluents and sludge from sewage treatment plants (STPs) (Clara et al, 2007;Martinez-Carballo et al, 2007a, 2007bMerino et al, 2003a;Li et al, 2014). Other local point sources, such as hospitals, laundry wastewater (Kümmerer et al, 1997;Kreuzinger et al, 2007), and roof runoff ( Van de Voorde et al, 2012) also lead to its presence in the environment.…”

Quaternary ammonium compounds in soil: implications for antibiotic resistance development

“…For extractions procedures that need to be developed for soil sample screening, there are several recent multi-compound protocols for sewage-sludge available, which can serve as a point of reference (Martínez-Carballo et al 2007a;Li and Brownawell 2009;Li et al 2014a;Ruan et al 2014). Ruan et al (Ruan et al 2014) reported lowest limits of quantitation between 1 and 4 ng g -1 and presented the most versatile method.…”

“…However, this removal is partly caused by sorption to sludge. Total QAAC concentrations determined in the eight available studies on sewage sludge reach the mg kg -1 level (Gerike et al 1994;Fernández et al 1996;Merino et al 2003b; UBA Wien 2005;Martínez-Carballo et al 2007b;Kaj et al 2014;Li et al 2014b;Ruan et al 2014) with a median of 59 mg kg -1 and a mean of 220 mg kg -1 (SI Figure S3). The maximum content reported was 8 g kg -1 for DTDMAC (DADMAC-C14-C18) in an anaerobic sludge (Gerike et al 1994) but this concentration should be considered with caution due to the colorimetric detection procedure as disulfine blue complexes form and likely a result in overestimation.…”