Significance and Use
This Practice has been developed in support of the US EPA Office of Water, Office of Science and Technology by the Chicago Regional Laboratory (CRL).
Nonylphenol (NP) and Octylphenol (OP) have been shown to have toxic effects in aquatic organisms. The prominent source of NP and OP is from common commercial surfactants which are longer chain APEOs. The most widely used surfactant is nonylphenol polyethoxylate (NPnEO) which has an average ethoxylate chain length of nine. The APEOs are readily biodegraded to form NP1EO, NP2EO, nonylphenol carboxylate (NPEC) and NP. NP will also biodegrade, but may be released into environmental waters directly at trace levels. This Practice screens for the longer chain APEOs which may enter the STP at elevated levels and may cause a STP to violate its permitted discharge concentration of nonylphenol.
1.1 This procedure covers the determination of nonylphenol polyethoxylates (NPnEO, 3 ≤ n ≤ 18) and octylphenol polyethoxylates (OPnEO, 2 ≤ n ≤ 12) in water by Single Reaction Monitoring (SRM) Liquid Chromatography/ Tandem Mass Spectrometry (LC/MS/MS) using direct injection liquid chromatography (LC) and detected with tandem mass spectrometry (MS/MS) detection. This is a screening Practice with qualified quantitative data to check for the presence of longer chain ethoxylates in a water sample.
1.1.1 All data are qualified because neat standards of each alkylphenol ethoxylate (APEO) are not available and the synthesis and characterization of these neat standards would be very expensive. The Igepal® Brand standards, which contain a mixture of various chain lengths of the alkylphenol ethoxylates (APEOs), were used. The mixture was characterized in-house assuming the instrument response at an optimum electrospray ionization cone and collision voltage for each APEO was the same. This assumption, which may not be accurate, is used to determine qualified amounts of each ethoxylate in the standards. The n-Nonylphenol diethoxylate (n- NP2EO) surrogate was available as a neat characterized standard, therefore, this concentration and recovery data was not estimated. APEOs are not regulated by the EPA, but nonylphenol, a breakdown product of NPnEOs, is regulated for fresh and saltwater dischargers. A request by a sewage treatment plant (STP) was made to make this Practice available through ASTM in order to screen for the influent or effluent from sources of APEOs coming into the STP. The interest lies in stopping the source of the longer chain APEOs from entering the STP in order to meet effluent guidelines. Based upon the above, this is a Practice rather than a Standard Method. A comparison between samples is possible using this Practice to determine which has a higher concentration of APEOs.
1.2 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 The estimated screening range shown in Table 1 was calculated from the concentration of the Level 1 and 7 calibration standards shown in Table 4. These numbers are qualified, as explained in Section 1, and must be reported as such. Figs. 1-5 show the SRM chromatograms of each analyte at the Level 1 concentration with the signal to noise (S/N) ratio. This is a screening Practice and method detection limits are not given. The S/N ratio for each analyte at the Level 1 concentration must be at least 5:1 for adequate sensitivity. If the instrument can not meet the criteria, the screening limit must be raised to an acceptable level.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
TABLE 1 Estimated Screening Range
|Analyte||Estimated Screening |
|15.6-250 (Not Estimated)|
FIG. 1 SRM Chromatograms NP3EO-NP8EO
FIG. 2 SRM Chromatograms NP9EO-NP14EO
FIG. 3 SRM Chromatograms NP15EO-NP18EO and n-NP2EO
FIG. 4 SRM Chromatograms OP2EO-OP7EO
FIG. 5 SRM Chromatograms OP8EO-OP12EO
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D1193 Specification for Reagent Water
D2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water
D3694 Practices for Preparation of Sample Containers and for Preservation of Organic Constituents
D3856 Guide for Management Systems in Laboratories Engaged in Analysis of Water
D5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analysis
E2554 Practice for Estimating and Monitoring the Uncertainty of Test Results of a Test Method in a Single Laboratory Using a Control Sample Program
EPASW-846 Test Methods for Evaluating Solid Waste, Physical/Chemical Methods
Alkylphenols ; Ethoxylates; Liquid Chromatography; Mass Spectrometry;
ICS Number Code 71.100.40 (Surface active agents)
ASTM International is a member of CrossRef.
Citing ASTM Standards
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