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September 22, 2010

Mr. Richard Krock

The Vinyl Institute

1737 King Street, Suite 390

Alexandria, VA, 22314

RE: Status of Method Development for Analysis of Hazardous Air Pollutants (HAPs)

Dear Mr. Krock:

The purpose of this letter is to advise you of the current status of the Method Development Project that 

Environmental Chemistry, Inc. (ECI) is conducting for The Vinyl Institute (VI). As you know, our focused method 

development/validation work was triggered by the observation of several VI members that EPA Method 8260 for solids 

(like PVC resin) did not appear to recover nearly as much vinyl chloride (VC) as Method 107. Method 107 was developed 

specifically for VC in PVC resin to ensure quantitative recovery. The difference between standard Method 8260 and 

concurrent Method 107 data was substantial – 8260 appears to recover only about 10-20% of the amount measured by 

Method 107. At the same time, several other HAPs were being detected as present in PVC resin via Method 8260, and 

there are significant questions about the recovery of these other HAPs from a PVC resin matrix.

Goals of the first phase of the method development project included:

1. Based on initial work done at Accutest, OxyVinyls and Westlake laboratories, as well as a limited instrument 

manufacturer literature search, there appeared to be an opportunity to modify Method 107 and/or Method 

8260 to analyze for most (all?) of the VI HAPs list using Method 8260. Thus, experimentation with sample 

pretreatments and Method 8260 analysis parameters was deemed a high priority.

2. Since it is believed that the group of water soluble HAPs could be analyzed via a single method, namely EPA 

Method 8015, experimentation using mixtures of the aldehydes and methanol are to be analyzed by direct 

aqueous injection Method 8015. It is also believed that these highly water soluble HAPs are partitioned 

mainly to the water phase of the slurry stripper PVC discharge, so recovery from PVC resin may not be 

important. Work will be conducted to determine if these water soluble HAPs are partitioned such that the 

amount of these HAPs in the water phase of the slurry stripper discharge can be used to represent the 

amount in the whole slurry stripper discharge.

3. Alternative methods may be appropriate for selected HAPs on the VI list. Initial work done by the OxyVinyls 

lab indicates that a colorimetric method may be selective and sensitive for formaldehyde, a water soluble 

HAP. The colorimetric method, in conjunction with a few EPA approved NCASI methods, will be evaluated as 

alternative methods to the more complex EPA Method 8315 (derivatization followed by liquid 

chromatography).

4. Review the data on hydroquinone (HQ), recognizing that it is in equilibrium with another HAP, benzoquinone 

(BQ) and prepare standards of both HQ and BQ to evaluate their analytical method response.

5. Other methods may be evaluated if the above investigations do not prove to be fruitful.

ECI began evaluation of different sample introduction techniques for Method 8260 on August 5, 2010. The 

purpose of this study was to gather additional information to determine if other sample introduction techniques such as 

Static Headspace or Dynamic Purge Methods are likely to yield better recovery than is currently obtained when analyzing 

resin samples by Method 8260 following methanol extraction. 

Initial evaluation of three different sample introduction techniques by Method 8260 was performed and from this 

data, a fourth technique was derived and subjected to further evaluation as described below.
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HAPS40 Method: Pre-treat for one hour at 90 degrees C in a hot block prior to loading in Autosampler and purging at 40 

degrees C using Method 8260 purge conditions. This technique is similar to the protocol presented by Georgia Gulf, ETC 

Lab. Note: Although the sample is heated to 90 for one hour, it cools down after being removed from the hot block. 

HAPS90 Method: This method is the same as HAPS40, except a 90 degree C purge temperature is used after 

pretreatment instead of 40 degrees. Note: Although the sample is heated to 90 for one hour, it cools down after being 

removed from the hot block prior to being purged at 90.

HAPD Method: This method uses a one hour continuous purge time at 90 degrees C.

A review of the calibration data from the HAPS40 and HAPS90 methods presented some initial concerns. These 

include:

Hydroquinone or Benzoquinone were not detected. 

Formaldehyde was removed from the compound list because Method 8260 does not scan to a low enough mass 

range to detect formaldehyde.

1,1,2,2 Tetrachloroethane was not present and appears to have converted to Trichloroethene. The pre-treatment 

step is most likely responsible for this occurrence since it did not occur when the instrument was calibrated using 

standard 8260 conditions with 40 degree purge temperature.

Vinyl acetate exhibited inconsistent response. This is possibly a result of the pre-treatment step as well, based on 

the calibration results obtained using regular 8260 conditions. 

Vinyl chloride and Acetaldehyde do not yield complete chromatographic peak separation but the quantitation ions 

are different, so co-elution should not be an issue when identifying and reporting compounds in samples.

Internal standard (IS) recovery was comparable to regular 8260 so the pre-treatment step does not appear to 

affect IS results. 

All other compounds were detected with no apparent issues.

Inconsistent response for 1,1,2,2-Tetrachloroethane was observed (converted to Trichloroethene).

Acetaldehyde, Vinyl acetate, 1,3-Butadiene,and Acetophenone all exhibited poor average response factors when 

compared to other compounds and to average response factors obtained under routine 8260 analysis. 

There was a noticeable decrease in the response factor for standard concentrations at and above 100 ppb for 

Vinyl chloride and other compounds. This would suggest that it may be necessary to calibrate over a lower 

concentration range when using the pre-treatment step.

ECI was unable to establish an acceptable calibration for the HAPD one hour continuous purge method. Several 

issues were encountered:

Results of triplicate (analysis of 3 different standards of same concentration, not consecutive runs of the same 

standard) analyses are not consistent.

Internal standard response is inconsistent.

Poor chromatography on early eluting peaks that will cause identification and quantitation problems with 1,3 

Butadiene. 

No recovery of Vinyl acetate, Vinyl bromide, Vinyl chloride, Methyl chloride and Ethyl chloride.

All retention times for internal standards, surrogate standards, and compounds of interest were approximately one 

minute later than in regular 8260 method.

It was suspected that the early eluting compounds were being pushed off the trap before the GC run starts due to 

the extended purge time and volume. A study was performed to determine the effect of purge time on the response for 

the compounds of interest. It was believed that the 60 minute continuous purge method at 90 degrees (HAPSD) was not 

working due to a loss of analytes, including vinyl chloride, as the purge time increased. Purge times between 15 and 60 

minutes were tested to determine the affect of purge time on analyte response. 
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The data clearly showed a reduction in response as the purge time is increased. In general, the response for 

lighter, early eluting compounds such as Vinyl Chloride, Acetaldehyde, and Chloromethane decreased significantly as 

purge time increased. From Method 8260, we know that total purge volume (purge flow rate times purge time) is a critical 

factor in the ability to obtain consistent acceptable response to the wide range of volatile compounds. The lab reduced 

the purge flow rate during a 60 minute purge time at 90 degrees to achieve a total purge volume similar to that normally 

used during Method 8260 analysis. Although some analytes showed higher response at the 60 minute purge time at 10 

mL/minute, lower response for compounds such as Chloromethane, Vinyl chloride, Chloroethane, Bromoethene, 1,1-

Dichloroethene, and Chloroform indicates that the response was not sufficient to support calibration for these six 

compounds.

8260 HM: Hybridization of Techniques Described in EPA Methods 5021, 5030, 5035

Upon evaluation of the information obtained from the various techniques and the purge times and purge flow data,

the lab established a five point calibration using the following pretreatment and purging conditions:

Sample Pre-Heat Temperature: @90 degrees 

Sample Pre-Heat Time: 60 minutes

Purge Temperature: @90 degrees 

Purge Time: 9 minutes 

Purge Flow: 40 mL/minute 

GC/MS Settings: Same as used during routine Method 8260 analysis

Note: No cooling occurred between the Sample Pre-Heat and Purge Start Time. The sample was preheated by 

the Autosampler directly in the purge tube and purging was initiated and continued at 90 degrees.

A Stripper Wet Cake (wet PVC resin from filtration of slurry stripper discharge) sample was analyzed three 

consecutive times (same sample aliquot analyzed over again) to evaluate recovery efficiency. The sample was placed in 

a 40 mL vial, pre-heated, and purged directly in the vial. After the first and second analysis runs, the sample was cooled 

to room temperature. Additional internal and surrogate standards were added through the septa with a small gauge 

needle as specified in EPA Method 5035. The results of the three consecutive runs using 0.5 gram of sample are shown 

in the attached table. Runs were made using 0.5 gram of sample and 1 gram of sample. The runs using 1 gram of 

sample exhibited erratic internal standard response, inconsistent results, and poor chromatography and were not 

evaluated.

Acetaldehyde and Chloroethane exhibited poor chromatographic behavior in the second and third runs using 0.5 

gram of sample. Slight retention time shifts were observed for Vinyl Chloride and Chloroethane in the first run. These 

shifts may have been due to the concentrations present. Results for Vinyl Chloride and Chloroethane in Run 1 are 

reported as estimated concentrations above the calibration range. The 200 ppb standard in the calibration curve was 

dropped from the calibration curve for Vinyl Chloride because the response factor was inconsistent with the response 

factor obtained at lower concentrations. It is possible that this reflects an error in the standard preparation or is an issue 

that can be solved with increased familiarity and experience with the new operating conditions.

It will be necessary to determine how results above the calibration range will be handled. While it is possible to 

accurately weigh sample weights less than 0.5 gram, consideration will need to be given to the impact on representative 

sub-sampling. Further work to investigate the acetaldehyde results is also recommended. Due to the poor 

chromatography associated with the second and third runs, it is unclear at this point if acetaldehyde was truly not 

recovered in the first run or if its presence in the second and third runs is an "artifact" or potential degradation by-product 

caused by the sequential heating and cooling (between runs) process. 1,1-Dichloroethane also shows higher 

concentrations in the second and third run than were expected. Acetophenone and 1,2-Dichloroethane show incomplete 

recovery in the first run, but are absent in the third run.

The result obtained for vinyl chloride was compared to the result provided for Method 107. The lab also analyzed 

the sample using traditional Method 8260 via methanol extraction. All methods were run on the same sample on the 

same day. Results were corrected to dry weight basis using the moisture results obtained by the lab that submitted the 

sample. 
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The results obtained by the Traditional Method 8260 (methanol extraction) were almost 10 times lower than the 

results obtained by Method 107. The results obtained by the Modified Method 8260 were 56 -69% of the value obtained 

by Method 107, depending on whether the first run or total of all runs are used for calculating the results from the Modified

Method 8260.

Dispersion resin and suspension resin from two other facilities were also analyzed. Evaluation of surrogate 

standard and internal standard response indicate that the method developed should work on various resin types. It also 

appears that the method developed can be used to analyze slurry samples without separation of the two phases if a 

homogenous subsample can be obtained.

Conclusion

The following modifications to the Sample Introduction Technique for Method 8260 appeared to yield the best 

success across the entire list of HAPs for the four techniques evaluated:

Pre-Heat Temperature: @90 degrees 

Pre-Heat Time: 60 minutes

Purge Temperature: @90 degrees 

Purge Time: 9 minutes 

Purge Flow: 40 mL/minute 

Initial data indicate recovery may be 5-10 times higher for Vinyl chloride than is obtained when analyzed using 

methanol extraction and Method 8260. The result of the split sample for Vinyl chloride was closer to what was obtained 

by the Benchmark Method 107 than has been seen in the past when results obtained from methanol extractions are 

compared to results from Method 107. However, multiple data points will be needed to determine if this is indeed the 

case.

Recommendations for Further Study Method 8260

Because of the multiple variations of modification to Method 8260 that were attempted, it was not possible to fully 

evaluate the performance of the final method modifications during this first phase of the method development study. 

Additional work should be conducted to further evaluate method performance using these conditions.

Further evaluation of chromatography and integration parameters to optimize calibration results.

Determine significance of surrogate recovery results for Toluene d8 and 4-Bromofluorobenzene. These are lower 

than would normally be expected in 8260, but might be associated with absorption into the resin.

Determine if the concentrations in the second and third extractions of the same sample are significant or if 

recovery in the first extraction is sufficient. This would prevent interference from potential 

degradation/decomposition reactions that are thought to be occurring due to sequential heating and cooling 

cycles. It is unlikely that recovery for compounds such as Acetaldehyde and Isopropylbenzene would be zero in 

the initial analysis based on prior performance data from Method 8260. The recovery data for 1,1-Dichlorethane 

and 1,2-Dichloroethane from the first analysis in the sequence was also unexpected and needs further research 

to determine if this is an anomaly. The poor chromatography for compounds in the second and third runs 

indicates that something unusual is occurring upon sequential analysis of the same sample aliquot. 

It is suspected that the retention time shifts that were observed for Vinyl chloride and Chloroethane during the first 

analysis sequence was due to the concentrations present in the sample relative to the calibration standard. 

Further evaluation of the chromatograms will confirm this idea.

Determine precision of analysis from replicate analysis of the same sample for suspension resin, dispersion resin, 

and slurry resin.

Perform a Method Detection Limit (MDL) study.

Determine minimum amount of sample that can be used (which will establish upper working range of method). It 

has already been determined that there is also an upper limit to the sample amount that can be used.
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Acetophenone appeared to demonstrate good performance using an extended purge time. A decision should be 

made whether or not to pursue this option as an alternative to Method 8270. The recovery of Acetophenone in 

the first of three consecutive extractions using the 60 minute Pre-treat method was 39% of the total from three 

consecutive extractions. Acetophenone was not detected in the third consecutive extraction. The QC targets that 

were adopted from Method 8270 were 35-119% recovery. Additional work to determine potential for carryover 

and reproducibility using Modified Method 8260 may be warranted.

Hydroquinone and Benzoquinone were not detected during Method 8260 analysis. However, because of the 

number of different pre-treatment options being evaluated, ECI did not determine if pH adjustment would affect 

the ability to analyze these compounds by purge and trap. Since method performance of Method 8270 is known 

to yield poor recoveries for these analytes, it would be worthwhile to run at least one standard at a basic pH using 

the 60/90 Pre-Heat option.

Collect additional samples to be analyzed by EPA Method 8260 (methanol extract) and the 60/90 Pre-Heat 

Sample Introduction Technique to determine if the initial finding of improved recovery is statistically significant. A 

minimum of 20 samples would be needed to perform statistical evaluation of the data.

Water Soluble HAPs (Methanol, Acetaldehyde, Formaldehyde, Acetophenone)

ECI also performed evaluations of Method 8015 and the colorimetric procedure for Formaldehyde. The 

evaluation for these methods/compounds was conducted in an attempt to determine if the HAPs are so preferentially 

partitioned to the water phase (including that washed off the resin particles with a water rinse/extraction), that the amount 

of them in the solid resin phase is negligible. This would allow future analysis of the water phase of the slurry without 

needing to perform a separate solvent extract of the solid resin phase. No conclusions have been reached due to 

analytical problems encountered upon method development for these compounds using Method 8015.

Thank you very much for the opportunity to work with the Vinyl Institute on this project. ECI will prepare a final 

report of this first phase of the method development and submit to the VI on or before October 2, 2010. If you have any 

questions, please contact me at 713-666-0020 or via e-mail at nthomey@envchem.com.

Sincerely,

Nan Thomey

President
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Results of Method 8260 HM

Hybridization of Techniques Described in EPA Methods 5021, 5030, 5035

Modified Method 8260, Consecutive Purge, 

60 minute Pre-Heat at 90o, 9 Minute Purge @ 90o

With Comparison to Methods 107 and 8260 Methanol Extracts

Stripper Stripper Stripper Total

% 

Rec % Rec % Rec

Total 

of 3 

Runs

Method 

107

Method

8260 

Methanol 

Extract

Wet Cake 

Run 1

Wet 

Cake 

Run 2

Wet Cake 

Run 3 Runs 1-3

Run 

1

Run

2

Run

3

ppm, 

Dry 

Wt

ppm, 

Dry Wt

ppm, Dry 

Wt.

Chloromethane ND ND ND ND

Acetaldehyde ND 1090 RP 725 RP 1815 0 60 39.9

Vinyl chloride 1300 ER 300 ND 1600 81.2 18.8 0 2.9 4.2 0.481

1,3- Butadiene ND ND ND ND

Chloroethane 2070 ER 624 P 210 RP 2904 71.2 21.5 7.2

Bromoethene ND ND ND ND

1,1- Dichloroethene ND ND ND ND

1,1- Dichloroethane 194 155 101 450 43.1 34.4 22.4

Vinyl Acetate ND ND ND ND

2-Chloro- 1,3-butadiene ND ND ND ND

Chloroform ND ND ND ND

1,2- Dichloroethane 133 87 ND 220 60.4 39.5 0

Benzene ND ND ND ND

Toluene ND ND ND ND

m-Xylene, p-Xylene ND ND ND ND

o-Xylene ND ND ND ND

1,1,2,2-Tetrachloroethane ND ND ND ND

Isopropylbenzene ND 91 52 143 0 63.6 36.4

Acetophenone 2090 3260 ND 5350 39.1 60.9 0

Dibromofluoromethane, SR 94 71 63

Toluene, d8 SR 62 67 79

4-Bromofluorobenzene, SR 32 78 88

E - Reading above highest Calibration Standard (Have not determined Upper Linear Range or best way to handle dilutions.

R- Retention Time Shift

P - Poor Chromatography

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