Nonylphenol ethoxylate (NPE) is used commercially as a non-ionic surfactant in detergent formulation. The nine-mole ethoxylate is the most prevalent isomer used, and it readily biodegrades to form lower mole ethoxylates. Predominantly, the one, two and three ethoxylate moieties, along with nonylphenol (NP), are formed. Nonylphenol has been labeled as a weak endocrine disrupter and therefore the subject of numerous studies.

Reference Method:  in house

Detection Limits:

	Water	Soil
Analyte	Detection Limit	Detection Limit
	(µg/L or ppb)	(µg/g or ppm)
p-nonylphenol	0.01	0.010
p-nonylphenol monoethoxylate	0.02	0.020
p-nonylphenol diethoxylate	0.02	0.020