Behavior of alkylphenol polyethoxylate metabolites during soil aquifer treatment.
The attenuation of alkylphenol polyethoxylates (APEOs) metabolites was studied at a soil aquifer treatment (SAT) site located in Arizona, USA. Two parcels of water were monitored during infiltration; one parcel was predominantly oxic while the other was predominantly anoxic. In this study, only alkylphenol ethoxycarboxylates (APECs) and carboxyalkylphenol ethoxycarboxylates (CAPECs) were detected, no short-chained APEOs were observed-even under anoxic conditions. APEO metabolites were rapidly (<7 days) removed under both aerobic and anoxic conditions. In general, the length of the ethoxycarboxylate chain decreases with depth--at depths greater than 3m, only alkylphenoxy acetic acids (AP1ECs), carboxyalkylphenoxy acetic acids (CAP1ECs), and alkylphenols (APs) remain. Under aerobic conditions, octylphenol and nonylphenol concentrations decreased by approximately 80% (w/w) within 3m of the ground surface. Under anoxic conditions however, alkylphenol concentrations increased by approximately 200% during the first 1.5m and then decreased during the next 1.5m; overall, under anoxic conditions, alkylphenol concentrations increased by approximately 38% within 3m. During infiltration, APEC and CAPEC concentrations decrease by more than 95% within 3m of SAT. Alternate flooding and drying cycles appear to enhance overall APEO metabolite removal efficiencies.
Montgomery-Brown
John
J
Department of Civil and Environmental Engineering, Terman Engineering Center, Stanford University, Stanford, CA 94305-4020, USA.
Drewes
Jörg E
JE
Fox
Peter
P
Reinhard
Martin
M
D000085:Acetates / Q000032:analysis; D004190:Disasters; D004784:Environmental Monitoring; D010636:Phenols / Q000032:analysis / Q000378:metabolism*; D011108:Polymers; D012989:Soil Pollutants / Q000302:isolation & purification*; D014872:Water Movements; D014881:Water Supply
D000085:Acetates; D010636:Phenols; D011108:Polymers; D012989:Soil Pollutants