Table 1.

A summary of the analytical methods applied to measure chemical contaminants. ACN = acetonitrile, MeOH = methanol

Method number	Method name (reference)	Analytes	Sampling container and dechlorination agent	Sample holding time	Sample extraction (Solvents/reagents) [LFB/LFM concentration]	Sample analysis	Calibration type
1	USGS Direct Injection (Furlong et al., 2014)	110 pharmaceuticals and personal care products	40 mL VOA vial w/ 100 mg ascorbic acid	96 h	Direct injection of a 100 μL sample aliquot [200 ng/L]	ESI triple quadrupole LC-MS/MS with MRM	Isotope dilution with 20 labeled standards
2	USEPA Pharmaceutical (Batt et al., 2008)	54 human use prescription pharmaceuticals	500 mL amber glass w/ 50 mg ascorbic acid	72 h	SPE with mixed mode OASIS MCX (ACN, MeOH, formic acid, and ammonium hydroxide) [500 ng/L]	ESI triple quadrupole UPLC-MS/MS with MRM	Isotope dilution with 32 labeled standards
3	USEPA Hormone (SI Document 1)	12 steroids, hormones, bisphenol A, atrazine, triclosan	600 mL silanized clear glass w/ 6 mg copper sulfate and 7 mg ascorbic acid	72 h	SPE with C18 Disk (acetone, MeOH, dansyl chloride, hexane, hydroxylamine) [1.7 ng/L]	ESI LC-FTMS with accurate mass	Isotope dilution with 12 labeled standards
4	USGS Antidepressant (Schultz and Furlong, 2008)	11 antidepressant pharmaceuticals and degradates	1-L white polyethylene with 100 mg ascorbic acid	96 h	SPE with OASIS HLB (MeOH, ammonium acetate, acetic acid) [500 ng/L]	ESI hybrid triple quadrupole/ion trap LC-MS/MS with MRM	Isotope dilution with 1 isotopically labeled standard
5	USGS Wastewater (Steven et al., 2002)	63 wastewater contaminants	1-L amber glass with 100 mg ascorbic acid	96 h	SPE with Polystyrene- divinylbenzene (dichloromethane and diethyl ether) [2 μg/L]	GC–MS with capillary chromatography and electron impact ionization	Internal calibration with 6 internal standards and 4 surrogate compounds
6	USGS Pharmaceutical (Cahill et al., 2004)	14 pharmaceuticals	1-L amber glass with 100 mg ascorbic acid	96 h	SPE with OASIS HLB (methanol, trifluoroacetic acid) [250 ng/L]	ESI single quadrupole LC-MS with SRM	Internal calibration with 1 internal standard and 1 surrogate compound