Amines, C12-18-alkyldimethyl, N-oxides

Endpoint summary

Additional information

The removal of C12/14 amine oxide from wastewater by sewage treatment was determined in a monitoring study in The Netherlands between May and July, 1996 [Debaere G (1996c)]. Six municipal activated sludge treatment plants in The Netherlands were included. The concentration of C12/14 amine oxide was determined in influent and effluent samples. Samples (raw and treated sewage) were collected from the six municipal activated sludge sewage treatment plants (STP) over three consecutive days. The samples were analysed by FI/MS/MS for both C12 and C14 Amine oxide. The removal of Amine oxide during activated sludge sewage treatment was >95 to >99% at the six plants. The level of Amine oxide in effluent was below detection in all effluent samples (<0.43 µg/L). The amount of Amine oxide in influent ranged between 9-130 ug/L. The BOD removal at the six plants was 96 to >98%.

A second environmental monitoring study was conducted at ten sewage treatment plants (STP) across the[Miami Valley Laboratories (2001)].. The study included the five most common types of STPs found in the: Activated Sludge, Trickling Filter, Lagoon, Rotating Biological Contactor (RBC), and Oxidation Ditch. At each of the ten STPs, samples of influent and effluent were collected for the analysis of Amine Oxide. The monitoring was conducted at STPs located in nine major drainage basins in the

Total AO influent concentrations ranged from 2.3 to 28 ug/L. Total AO effluent concentrations ranged from 0.4 ug/L to 2.91 ug/L.  Percent removal of AO varied widely (63 -97%) among sewage treatment plants (STP) sites sampled. The variability of the influent concentrations appeared to be largely responsible for the inconsistencies in the % removal values. The 5 plants with >90% removal had high influent levels of AO (10.5 -27.8 ug/L), while the 5 plants with <90% removal had low influent levels of AO (2.3 -12.2 ug/L). The highest removals of AO were typically observed at Activated Sludge STP's (up to 97%). The lowest removals (as low as 63%) were observed at Oxidation Ditches. Five of the ten STP samples had AO removal greater than 90%.

The 3 activated sludge (AS) plants had removals of 96, 97, and 75%. The AS plant with the lowest removal (75%) had a low influent concentration of AO (2.9 ug/L). The 2 oxidation ditch (OD) plants had removals of 63 and 64%. One OD plant had a low influent level of AO (2.31 ug/L). The 2 lagoons had removals of 95 and 86%. The plant with lower removal (86%) had a low influent level of AO (6.3 ug/L). The 1 rotating biological contactor plant had a removal of 94%, and the highest influent level of AO (27.8 ug/L). The 2 trickling filter plants had removals of 91 and 82%. The TF plant () with the lower removal (82%) was operating poorly at the time of sampling.