United States
Environmental Protection
Agency
Environmental Monitoring and
Support Laboratory
Cincinnati OH 45268
Research and Development
EPA/600/S4-85/052 Dec. 1985
&EPA Project Summary
Standardization of EPA
Method 8610
T. F. Cole, A. Riggin, and S. V. Lucas
U.S. EPA Method 8610, "Total Aro-
matics by Ultraviolet Absorption" was
evaluated in conjunction with U.S. EPA
Method 3560, "Reverse Phase Cartridge
Extraction" for the separation and qual-
itative determination of the presence or
absence of visible or ultraviolet ab-
sorbing organic compounds listed in
Appendix VIII of the Resource Conser-
vation and Recovery Act (RCRA). A data
base of the visible and ultraviolet (UV)
spectral data for these compounds was
developed and used to estimate detec-
tion limits of Appendix VIII organic
compounds which absorb UV or visible
light in the region 220 to 700 nm. The
reverse phase cartridge extraction pro-
cedure of Method 3560 was evaluated
for its ability to separate polar and non-
polar subsets of 21 Method 8610 ana-
lytes by the use of methanol and hex-
ane eluents. The extraction procedure
was found to be unsuitable for group
separation in its present form, and
needs further study in order to evaluate
the behavior of individual analytes such
as acids, bases, and polynuclear aro-
matic compounds. The spectrophoto-
metric determinative technique of
Method 8610 was found to be very sen-
sitive for a majority of the compounds
in the range of 220 to 400 nm, but re-
quires further evaluation with a variety
of groundwater samples in order to
study the matrix effects of groundwa-
ter on the sensitivity of the method.
This Project Summary was devel-
oped by EPA's Environmental Monitor-
ing and Support Laboratory, Cincinnati,
OH, to announce key findings of the
research project that is fully docu-
mented in a separate report of the same
title (see Project Report ordering infor-
mation at back).
Introduction
The Environmental Protection
Agency (EPA) has proposed an amend-
ment (October 1,1984 Federal Register)
to its hazardous waste regulations
under the Resource Conservation and
Recovery Act (RCRA) consisting of a hi-
erarchical analysis procedure for
groundwater testing. The proposed hi-
• erarchical procedure would allow haz-
ardous waste facility operators to
quickly screen groundwater samples for
compounds of concern using relatively
inexpensive methods, thus reducing
their overall testing burden for regu-
lated pollutants witho'ut jeopardizing
environmental protection.
One of the proposed methods in-
cluded in the hierarchical analysis pro-
tocol is Method 8610, "Total Aromatics
by Ultraviolet Absorption." When used
in conjunction with Method 3560,
"Reverse Phase Cartridge Extraction,"
Method 8610 is intended to enable oper-
ators of hazardous waste facilities to
cost effectively monitor groundwater
beneath their facilities for a large num-
ber of regulated compounds and make
decisions for advanced testing.
In an effort to evaluate the usefulness
of Methods 3560 and 8610, EPA con-
tracted Battelle's Columbus Laborato-
ries, under Contract Number 68-03-
1760, to conduct a research program to:
(1) generate a data base of ultraviolet
and visible spectral data for Method
8610 analytes; (2) evaluate Method
3560 for the collection and separation of
polar and nonpolar Method 8610 ana-
lytes; and (3) evaluate Method 8610 for
the analysis of total aromatic com-
pounds.
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Evaluation of Method 8610
The work completed under the evalu-
ation of U.S. EPA Method 8610 was con-
ducted in three segments: (1) acquisi-
tion of reference spectral data on both
polar and nonpolar aromatic com-
pounds and the development of a data
base of this information; (2) the devel-
opment of a subset of Method 8610 ana-
lytes for verification of the literature in-
formation and for estimated detection
limit (EDL) evaluation; and (3) determi-
nations of UV/visible spectra of com-
mercially available method analytes for
which no literature data was available.
Development of the UV and
Visible Spectral Database
A data base of physical properties and
spectral data of the 90 polar and 39 non-
polar organic analytes listed in Method
8610 was created using Lotus 1,2,3 soft-
ware and an IBM personal computer.
The spectral information has been pre-
sented in 10 nm windows to aid in the
potential development of further refine-
ments to the method. Files for this data
base were stored on 5-1/4" floppy disks.
Except for polychlorinated biphenyls
(PCBs), physical and spectral data for
analytes which consisted of a group of
isomers were searched as individual
isomers. Since PCBs include 208 indi-
vidual isomers, the literature search
was directed only towards the thirteen
common commercial formulations
(Aroclors). Of the 90 polar compounds
listed in Method 8610, at least two dif-
ferent literature sources of spectral data
were found for 70 compounds, and one
literature reference was found for 11
compounds. No spectral information
was available for the remaining nine
compounds. For the 39 nonpolar ana-
lytes, at least two different literature
sources of spectral data were found for
each compound (except PCBs).
Evaluation of Detection Limits
Methanol solutions containing 0, 2.5,
5, 25 and 50 ppm of benzene were used
to assess the signal to noise and detec-
tion limit capabilities of both the Gary 14
and the Gary 17D scanning spectropho-
tometers. For the Gary 14, an absor-
bance reading of 0.05 to 0.1 absorbjnce
units was necessary to distinguish a
positive response from the normal
background noise level (about 0.01 au)
of this instrument. Similar data ob-
tained on the Gary 17D indicated that
an absorbance reading of 0.005 is read-
ily discernable from the background ab-
sorbance of the reagent blank and is
well above the noise level of this instru-
ment. Thus, a scanning spectrophoto-
meter with performance characteristics
equal to or better than the Gary 17D
would be required to meet the proposed
decision level of 0.005 au in Method
8610.
EDLs were computed using 0.005 au
as the detection limit value and by mak-
ing several assumptions with respect to
the method and compounds under con-
sideration: (1) a 100 mL aqueous sam-
ple, (2) a Method 3560 elution volume of
5.0 ml of methanol or hexane and anal-
ysis without further concentration,
(3) quantitative recovery in a single
5.0 mL eluate, and (4) use of an average
molecular weight of 200 g/mole. EDLs
estimated for these conditions versus
molar absorptivities are presented in
Table 1.
Evaluation of Method 3560
The reverse phase cartridge extrac-
tion procedure of Method 3560 was
evaluated with a subset of compounds
chosen from the Method 8610 analyte
list. The extraction procedure was eval-
uated for elution solvent order and for
effectiveness of the reverse phase car-
tridge cleanup and equilibration
scheme. The subset compounds from
Method 8610 were evaluated for their
elution characteristics and percent re-
coveries with a modified solvent elution
scheme.
Column Cleanup Evaluation
UV spectra of methanol washes of
6-mL C18 columns (Baker-10 SPE)
showed that the cleanup procedure
prior to the use of the GIS columns as
supplied by the manufacturer is essen-
tial. Since Method 3560 specifies the
generation of both methanol and hex-
ane elutes, the proper cleanup steps are
5 mL of hexane followed by 5 mL of
methanol and, finally, 10 mL of reagent
water to prepare the column for the
aqueous sample. One problem with 1
original Method 3560 procedure v\
the use of hexane as the first eluti
solvent after column extraction 01
100 mL aqueous sample. Since hexa
is a much stronger reverse phase s
vent than methanol, a second eluti
with methanol would be superfluo
and no polarity separation could
achieved. Furthermore, since hexane
not miscible with water, the residi
water on the column packing could p
vent efficient elution of the colunr
These expected problems were inde
observed when the specified hexar
methanol order was used. Therefoi
the order was reversed to the corre
one (methanol/hexane) for all the spi
recovery experiments performed.
Evaluation of Solvent Elution
of Selected Compounds
Selected compounds were individ
ally spiked directly onto pre-clean<
cartridges using 10 (jil of methanol. Tl
columns were then serially eluted wi
5 mL each of reagent water, methani
hexane, and a second hexane elutio
and the UV spectrum of each 5 mL el
ate was recorded. The second hexat
elution was used to determine wheth
complete elution from the column w;
achieved. The compounds were spikt
directly onto the columns rather the
into a 100 mL water sample to sep
rately examine elution characteristics <
the 5 nonpolar and 15 polar compounc
tested. The results of this elution evali
ation are presented in Table 2. Thes
results suggest a number of conclt
sions regarding the application (
Method 3560 to Method 8610 analytei
• The extraction/elution procedui
used is not capable of group separ;
tion into polar and nonpolar con
pounds, as evidenced by the fai
that all five of the nonpolar con
pounds of Table 2 were at least pa
tially present in the methane
Table 1. Estimated Detection Limits of Method 8610 Compounds Based on Molar Absorpth
ities
Absorptivity
Range (e)
W2 - W3
W3 - W4
W4 - W5
Unavailable
EDL, ng/L of
Groundwaterlal
500
50
5
Number of
Compounds In
the Given Flange
Polar
4
37
39
W
Nonpolo
9
6
23
1
MEDLs are based on average molecular weight of 200, a concentration factor of 20, and a minimur
absorption of 0.005 au for detection.
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Table 2. Recovery by Solvent Elution of Selected Polar and Nonpolar Aromatic Compounds Spiked Onto Reverse Phase Cartridges
Percent Recovered in Given Elution Solvent
Compound
Amount Spiked,
\igper
Cartridge
Reagent
Water Rinse
Methanol
Eluent
First Hexane
Eluent
Second
Hexane
Eluent
Total
Percent Recovery
Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 2 Average
Nonpolar Aromatic Compounds
Benzene 368
Dibenzo(a,j)acridine 9.2
1,3-Dichlorobenzene 2,580
Fluoranthene 10
Methoxychlor 27
Polar Aromatic Compounds
la)
21
11
62
57
74
21
11
62
51
74
18
4
15
50
40
15
5
30
54
43
10
13
49
15
77
115
114
MDash (-) indicates compound not detected in given fraction or replicate.
">'0n/y one replicate for aniline.
>c>The hexane fractions were inadvertantly not collected, partially explaining the relatively low average recovery shown.
49
16
92
111
117
49
16
84
113
116
Acetophenone
Aniline
Butylbenzylphthalate
3,3 ' -dichlorobenzidine
<2,4-Dichlorophenoxy)acetic acid
2,4-Dimethylphenol
2,4-Dinitrophenol
2,6-Dinitrotoluene
1,2-Diphenylhydrazine
Methylparathion
1,4-Naphthoquinone
Pyridine
Strychnine
Thioacetamide
2,4,6-Trichlorophenol
20
10
23
11
26
28
20
20
25
35
23
40
20
7.4
88
-
8
-
-
19
-
-
13
-
-
-
-
-
83
-
-
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T. F. Cole, A. Riggin, and S. V. Lucas are with Battelle, Columbus Laboratories.
Columbus, OH 43201 -2693.
FredK. Kawahara is the EPA Project Officer (see below).
The complete report, entitled "Standardization of EPA Method 8610," (Order No.
PB 85-247 013; Cost: $ 16.95, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Environmental Monitoring and Support Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $300
EPA/600/S4-85/052
OOOQ329
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