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5 Application of the Master Analytical Scheme to Polar Organic Compounds in Drinking Water A. W. Garrison and E. D. Pellizzari Downloaded by FUDAN UNIV on January 24, 2017 | http://pubs.acs.org Publication Date: December 15, 1986 | doi: 10.1021/ba-1987-0214.ch005

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Environmental Research Laboratory, U.S. Environmental Protection Agency, Athens, G A 30613 Research Triangle Institute, Research Triangle Park, NC 27709 1

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The U.S. Environmental Protection Agency Master Analytical Scheme (MAS) for Organic Compounds in Water provides for comprehensive qualitative-quantitative analysis of gas chromatοgraphable organic compounds in many types of water. This chapter emphasizes the analysis of polar and ionic organic compounds—the more water-soluble compounds in the MAS repertoire—in raw and treated drinking water. Mean recoveries from drinking water made by using the MAS protocols that handle polar and ionic compounds were as follows: 84% for neu tral water-soluble organic compounds (25 compounds spiked at 1 μg/L), 89% for extractable semivolatile strong acids (24 com pounds spiked at 50-100 μg/L), 82% for volatile strong acids (18 compounds spiked at 0.3 μg/L), and 81% for strong primary and secondary amines (11 compounds spiked at 35 μg/L). The proto col for nonvolatile acids has not yet been applied to spiked drink ing water, but recoveries should be higher than the average of 85% (14 compounds spiked at 50 μg/L) obtained for these acids in industrial-municipal effluents. O R G A N I C C O N T A M I N A N T S I N W A T E R can be divided into three groups: 1, volatile (gas chromatographable) nonpolar; 2, polar of intermediate volatility; and 3, nonvolatile polar. This grouping roughly parallels Neal's (J) division of contaminants into three classes: 1, lipid soluble with molecular weight ( M W ) < 500; 2, more water soluble with M W < 500; and 3, lipid soluble and water soluble with M W > 500. A n y differences i n categorization are the result of current analytical opera tional limitations; for example, most contaminants in Neal's first group 0065-2393/87/0214/0083$06.00/0 © 1987 American Chemical Society

Suffet and Malaiyandi; Organic Pollutants in Water Advances in Chemistry; American Chemical Society: Washington, DC, 1986.

Downloaded by FUDAN UNIV on January 24, 2017 | http://pubs.acs.org Publication Date: December 15, 1986 | doi: 10.1021/ba-1987-0214.ch005

84

O R G A N I C P O L L U T A N T S IN W A T E R

axe best separated b y gas chromatography ( G C ) , but as the M W increases f r o m 300 to 500, volatility decreases so that high-performance liquid chromatography ( H P L C ) often becomes the preferred technique. The third groups in both classification schemes are limited to H P L C separation. This chapter is limited to compounds in group 2 of both classifications, that is, polar, even ionic, water-soluble compounds of M W < 500 that are less lipid-soluble than those of group 1. These polar compounds, in most cases, are volatile enough for G C separation or can be made volatile enough b y derivatization. H o w e v e r , some of M W < 500 are still not volatile enough for G C under any conditions; these must be separated b y H P L C . These compounds are covered elsewhere in this book (2). T h e U . S . E n v i r o n m e n t a l Protection Agency ( U S E P A ) Master Analytical Scheme ( M A S ) for Organic C o m p o u n d s in Water (3) provides for comprehensive qualitative-quantitative analysis of most gas chromatographable organic compounds in many types of water. These compounds include the purgeable and solvent-extractable, relatively nonpolar, lipid-soluble compounds. They also include the more water-soluble polar and ionic compounds that usually cannot be isolated from water with conventional solvent extraction and are usually not gas chromatographable without derivatization. Again, this chapter is limited to polar and ionic compounds, in raw and treated drinking water, that are amenable to M A S analysis.

MAS Protocols Figure 1 is a f l o w diagram of M A S procedures. The polar compounds discussed here are covered b y six protocols: 1. N E W S : neutral, water-soluble, low-molecular-weight compounds concentrated b y azeotropic distillation then isolated b y a heated purge and trap procedure (alcohols, aldehydes, nitriles, etc.). 2. E S S A : extractable, semivolatile, strong acids extracted at p H 1 (less volatile carboxylic acids, strong phenols, etc.). 3. V O S A : volatile, strong acids isolated on anion-exchange resin (volatile carboxylic acids, generally < C - 9 ) . 4. N O V A : nonvolatile, strong acids isolated on anion-exchange resin (certain carboxylic acids, sulfonic acids, etc.). 5. S A M - P T and S A M - S : strong amines isolated on cationexchange resin (primary, tertiary, and secondary amines, primarily aliphatic). 6. W A B N - S C : weak acids, bases, and neutrals isolated at p H 8.0 on X A D - 4 resin (weak phenols, anilines, and a wide variety of neutral compounds).


5.

GARRISON A N D PELLIZZARI

85

Polar Organic Compounds

A l l protocol extracts or isolates are analyzed b y capillary column G C - m a s s spectrometry ( G C - M S ) ; all except the N E W S and W A B N must be derivatized before analysis.


Recovery, Precision, and Sensitivity During development of the M A S , extensive recovery studies were conducted to verify protocols and to f o r m a data bank for future use in quantitative analysis. T w o hundred and seventeen different model compounds from a w i d e variety of chemical classes and physical property groups were dosed into drinking water; accuracy (recovery) and precision were determined for each compound and for each class of organic within each analytical protocol. [Recovery data for 327 organics i n several types of water obtained b y using all of the M A S protocols were presented at the 186th meeting of the American C h e m i cal Society in Washington, D C , in September 1983 (4).] Table I shows the summarized recovery data with spiking levels and precision. This table includes, for purposes of comparison with polar compounds, some data for nonpolar compounds [volatile organics (VO) and the neutrals i n W A B N ] ; also, the recoveries for N O V A are not for drinking water. The mean recovery for 217 compounds was 82S>; the mean relative standard deviation (RSD) (for three or more measurements) was 123d. Several observations can be made i n regard to these data: (1) The best recoveries and precision are obtained for V O and E S S A compounds. (2) N E W S organics, a new class of analytes, are Table I. Summary of MAS Recovery Data for Organics in Drinking Water by Protocol Class

Protocol Class

No. of Compounds

Spiking Range (ppb)*

VO NEWS WABN-SC ESSA VOSA SAM-PT and SAM-S Total NOVA

52 25 87 24 18 11 217 14

0.2-1.8 0.8-1.2 0.5-5 50-100 0.3 35 — 50

Nominal Spiking Level (ppb)* 1 1 1 55 0.3 35 — 50

Mean Recovery (%)

Mean RSD (%)

m 84 74 89 82 81 82 85

10 16 12 9 10 12 12 20

b

b

N O T E : For all protocol classes except N O V A , triplicate determinations were made from drinking water. For N O V A , triplicate determinations were made from industrial-municipal effluents. Values indicate level spiked into water sample. These mean recoveries and mean RSDs were calculated from the individual values for the 217 compounds.

a


Suffet and Malaiyandi; Organic Pollutants in Water Advances in Chemistry; American Chemical Society: Washington, DC, 1986. Extract Processing '

Isolation from Aqueous Matrix

\

Addition of Internal Standards

Sample Handling "

Volatiles ·

Derivatization of 5 Fractions ο ESS A methyl esters/ethers ο VOSA benzyl esters ο NOVA methyl esters/ethers ο SAM-PT Schiff bases ο SAM-S pentaf/uorobenzyl amines

Other Ionic Compounds (4 fractions from ion-exchange resins)

• Extractables

• Neutral. Water Soluble, Low Molecular Weight Compounds

•

Purgeab/es (2) Extractables (2) Other Ionic Compounds (3)

•Sorbent Accumulator (WABN-SC) (drinking water only)

•Continuous Flow-under (WABN-FU (emulsion prone samples)

"•Batch Liquid-Liquid (WABN-BL) (separatory funnel)

-^Semivolatile Strong Acids (ESSA)

Volatile Strong Acids (VOSA) Nonvolatile Strong Acids (NOVA) Primary and Tertiary Amines (SAM-PT) Secondary Amines (SAM-S)

ο pHB.O — (3 alterna tive tech niques)

1.0-

Heated Purge and Trap (NEWS)

ο pH

-[o

-Jjô Purge and Trap on Tenax GC (VO)

• Collection (7 Sub-samples) —————— • Storage/preservation m Water quality scouting measurements (conductivity, headspace gas analysis, emulsion index, pH, and chlorine determination)



Y

Quantitative Analysis

Τ

Qualitative Analysis

GC-MS-COMP Analysis — (10 maximum fractions)

.. CGC .. CGC .. CGC

(WABN-BL1. WABN-BL2, WABN-BL3)

Figure 1. Master analytical scheme flow

Manual Calculations Operator Interactive Computer Program (MASQUANT)

*WABN-BL1 *WABN-BL2 *WABN-BL3

thermal de sorption into CGC thermal desorption into CGC CGC CGC CGC CGC CGC CGC

• Computer Searches Manual Interpretation

WABN-BL (Silica — subfractions

VO NEWS ........ ESSA VOSA NOVA SAM-PT SAMS WABN

3 subfractions

of 8 fractions

• Addition of external standard

m Εvaporation/concentration

ο WABN-BL

• Clean-up ofpH 8 extractables (Silica column)



88

ORGANIC POLLUTANTS IN WATER

recovered w e l l with adequate precision. (3) T h e three classes of ionizable compounds that are isolated on ion-exchange resins ( V O S A , S A M , and N O V A ) are recovered well with adequate precision. (4) The lowest recoveries are for the M A S protocol fraction containing the largest number of c o m p o u n d s — W A B N - S C . Comparisons can be made with recoveries f r o m other matrices, especially industrial and municipal effluents. F o r example, recoveries of V O and N E W S compounds are practically the same for drinking water and for effluents; this result indicates the lack of matrix effects. O n the other hand, the t w o classes of ionizable organics, V O S A and S A M , that were studied i n both matrices were recovered significantly better and with better precision f r o m drinking water than f r o m the effluents. Thus, w e deduce that the recoveries of N O V A compounds w i l l be even better in drinking water than the 85% average recovery f r o m effluents. Finally, the relatively poor recovery and precision (742 with R S D of 12?) of W A B N organics f r o m drinking water, b y using the prescribed accumulator-column isolation technique for added sensitivity, are still better than those f r o m the effluents (69* with R S D of 20«), where batch liquid-liquid extraction is used. Recovery data for the separate chemical classes in each M A S protocol are given in Table II. Data are included for all protocols, including those for nonpolar compounds. These data are for all types of water studied, not just drinking water; footnotes to Table II give information on sample matrices and spiking levels. Chapter 1 of the M A S protocols (3) gives recovery values for each individual analyte, including separate values for each analyte in drinking water for each protocol except nonvolatile acids. T h e M A S protocols (3) and experimental reports (5) provide some insight into experimental difficulties that may cause some of the poorer recoveries and precision values of Table II. N o m i n a l detection limits for the M A S as applied to drinking water range from 0.1 Mg/L for V O and N E W S compounds to 5 Mg/L for E S S A compounds.

Conclusions Application of the M A S to drinking water should considerably broaden the scope of organic compounds detected and measured, relative to previously available analytical methods. This conclusion is especially true for the polar compounds of relatively l o w M W ( 2

e d /

| > ζ α

>

·

e

Continued on next page.



Aromatic aldehydes and ketones (o-tolualdehyde; acetophenone) accumulator column batch liquid-liquid Aromatic esters and sulfonates (benzyl acetate, ethyl p-toluenesulfonate) accumulator column batch liquid-liquid Misc. aromatic compounds (nitrobenzene; tetraphenyltin) accumulator column batch liquid-liquid Deuterated standards (dio-xylene; cfe-phenol; dô-aeetophenone; ds-phenylethanol; d^-nitrobenzene; efe-propiophenone; de-naphthalene; cfe-acridine; di2-perylene) accumulator column batch liquid-liquid

Protocol Class Chemical Class (Examples)

74

78 58

47- 89 48- 105

55-93 40-78

6 10

84

92

Mean Recovery (%)

46-87 55-138

88-96 43-105

Recovery Range (%)

6 7

Compounds Studied

Table II. Continued

10 26

13 17

6-24 8-33

4-21 11-40

12 11

12 13

Mean RSD (%)

7-17 3-19

2-17 6-19

RSD Range (%)


d e

d e

d e

Footnotes

Suffet and Malaiyandi; Organic Pollutants in Water Advances in Chemistry; American Chemical Society: Washington, DC, 1986. 2

ESSA Carboxylic acids (benzoic acid; palmitic acid) Phenols (2-nitro-p-cresol; pentachlorophenol) Deuterated standards (di3-heptanoic acid; cfc-benzoic acid) VOSA Volatile carboxylic acids (acrylic acid; 1-octanoic acid) Deuterated standards (ch-butyric acid) NOVA Carboxylic acids (succinic acid; 2,4,5-trichlorophenoxyacetic acid) Sulfonic acids (benzenesulfonic acid; 2-naphthalenesulfonic acid) Misc. nonvolatile acids (benzenephosphoric acid; pentachlorophenol) Deuterated standards (2-naphthalenesulfonic acid-d7-H 0) 63-110 88-100 65-92

46-90 — 42-87 84-110 62-140 —

17 5 2

16 1 6 4 3 1

110

102

96

64

8

65

79

94

89

5

1

—

11-50

7-45

2-45

—

4-34

6-12

4-19

2-20


14

25

23

18

i

i

i

i

h

h

g

g

g

Continued on next page.

4

19

9

8

9


40-98

6 1

58-86

Recovery Range (%)

11

Compounds Studied

75

63

72

Mean Recovery (%)

20-53

12-41

RSD Range (%)

27

36

24

Mean RSD (%)

i

Footnotes

1

g

e

c

Mean recoveries are for triplicate determinations from drinking water, spiked at 0.2-1.8 ppb (nominally 1 ppb), plus triplicate determinations from a 60-40 industrial-municipal waste water, spiked at 30-87 ppb (nominally 50 ppb). "Mean recoveries are for triplicate determinations from drinking water, spiked at 0.8-1.2 ppb (nominally 1 ppb), plus triplicate determinations from a 60-40 industrial-municipal waste water, spiked at 40-63 ppb (nominally 50 ppb). Mean recoveries are for triplicate determinations from 60-40 industrial-municipal waste water only, spiked at 40-63 ppb (nominally 50 ppb). "Mean recoveries are for triplicate determinations from drinking water, spiked at0.5-5 ppb (nominally 1 ppb), using X A D - 4 resin sorbent columns. M e a n recoveries are for triplicate determinations from a 60-40 industrial-municipal waste water or, for about 253? of the total compounds, from reagent water spiked at 15-50 ppb (nominally 25 ppb), using batch liquid-liquid extraction, with cleanup included. ' Mean recoveries are for triplicate determinations from reagent water only, with cleanup step included. (Interferences prevented recovery determinations from waste water.) Mean recoveries are from triplicate determinations from drinking water only, spiked at 50-100 ppb (nominally 55 ppb). Recoveries were not determined from more complex waters. Mean recoveries are for triplicate determinations from drinking water, spiked at 0.3 ppb, plus triplicate determinations from a 60-40 industrial-municipal waste water, spiked at 120 ppb. Mean recoveries are for triplicate determinations from several industrial and municipal effluents. ' Mean recoveries are for triplicate determinations from three industrial and two municipal effluents spiked at 110 ppb, and including, in some cases, triplicate determinations from drinking water spiked at 35 ppb. * Recoveries determined for only one (cfe-butylamùie) of the three internal standards.

0

SAM-PT and SAM-S Primary and tertiary amines (n-butylamine; tri-n-butylamine) Secondary amines (diallylamine; 2-methylpiperidine) Deuterated standards (db-butylamine; eirphenylethylamine; N-ethyl-2-fluorobenzylamine)

Protocol Class Chemical Class (Examples)

Table I I . Continued


5.

GARRISON A N D PELLIZZARI

Volar Organic Compounds

95

Literature Cited


1. Neal, R . A . Environ. Sci. Technol. 1983, 17(3), 113A. 2. Graham, J., Chapter 6 in this book. 3. Pellizzari, E. D. et al. Master Analytical Scheme for Organic Compounds in Water. Part I: Protocols; U.S. Environmental Protection Agency: Athens, GA, 1985; EPA-600/4-84-010a. 4. Pellizzari, E. D.; Garrison, A. W. Prepr. Pap. Am. Chem. Soc. Div. Environ. Chem. 1983, 23(2), 427-430. 5. Pellizzari, E. D. et al. Experimental Development of the Master Analytical Scheme for Organic Compounds in Water. Part I: Text; U.S. Environmental Protection Agency: Athens, GA, 1985; EPA-600/4-85-007a. R E C E I V E D for review August 14, 1985. A C C E P T E D February 13, 1986.


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