analysis of benzene and other vocs in consumer beverages ... · analysis of benzene and other vocs...

A Presentation by OI Analytical

Analysis of Benzene and Other VOCs in Consumer Beverages and Table-Ready Food

by Purge-and-Trap

A World of Solutions

Overview

• This presentation discusses the recent reports of benzene in some consumer beverages and includes the following information:– Introduction– Project definition– Analytical method and instrumentation– Sample preparation– Results from beverages and table-ready foods– Results from non-food consumer products– Conclusion and contact information

Introduction

• In November 2005, the FDA received reports that benzene, a human carcinogen, was present at low concentrations in some soft drinks containing benzoate salts and ascorbic acid.

• A resulting FDA survey of 100 products found that most of the beverages sampled contained either no detectable (ND) benzene or levels well below the USEPA water quality standard of 5 ppb.– There is no quality standard for benzene in consumer

beverages.– WHO water standard for benzene is 10 ppb.

• Four of the beverages tested in this survey contained benzene at levels above 5 ppb.

Source: http://www.fda.gov

Introduction (cont.)

• FDA’s Total Diet Study (TDS) results from 1995 to 2001 indicated that the levels of benzene may be higher.– Studies are underway to determine why the two sets of

test results were different.• Benzene has also been found in consumer beverages

internationally in the UK, Australia, and New Zealand.• The 2005 survey test results indicate that benzene

levels can be highly variable from lot to lot and may depend on factors such as time at elevated temperatures and exposure to light.

• Manufacturers are currently reformulating products that have been identified as containing greater than 5 ppb benzene.

Source: http://www.fda.gov

Project Definition

• An analytical method is demonstrated for the determination of benzene and other volatile organic compounds (VOCs) in consumer beverages and selected table-ready food products.

• Instrumentation included:– Eclipse 4660 P&T Sample Concentrator– Model 4552 Water/Soil Autosampler

• Naturally occurring VOCs, as well as contaminant residues from various sources (processing and packaging, flavor additives, breakdown products, etc.), can be determined by this method.

Overview of the Analytical Method

• VOC extraction, concentration, and introduction was performed by closed system purge-and-trap (P&T).– More sensitive than headspace methods– Lower detection limits– Cryogenic focusing is not necessary

• Compound speciation by gas chromatography• Detection and identification by mass spectrometry

– Scan or SIM mode• Quantitation using Internal Standard (IS)

Sample Introduction Instrumentation

Eclipse 4660 P&TSample Concentrator

Model 4552 Water/Soil Autosampler

Interior Model 4552 Water/Soil Autosampler

Standardvessels

Equilibriumblock

Watersyringe

Sample tray(cooling optional)

“Water” modesamplingstation

“Soil” modesamplingstation

“Water” Mode vs. “Soil” Mode

Beverage in the “Soil” sampling

station did not foam

• For this project, all samples were purged using the “Soil” mode on the Model 4552 Autosampler.

• This technique minimized loss of VOCs in the solid food products and

• Minimized foaming of the beverage samples.– Beverages foamed

excessively when purged in the “Water“ mode

Sample Purging in “Soil” Mode

• Internal standards and water are added to the sample in a sealed 40-mL VOA vial.

• The sample matrix is heated and stirred to improve purge efficiency.

• Purge gas sweeps the VOCs out of the matrix.

• VOCs are then collected at the top of the double sleeve needle and transferred to the trap for concentration.

VOCs carriedto trap

Purge gas IN

Sample stirred and heated to improve purge efficiency

Purge gas extracts

VOCs from the matrix

VOCs collected at top of the

double sleeve needle

Beverage Sample Preparation

• Samples were cooled to 4°C prior to sampling.• A syringe was used to transfer 5 mL from the original

container to the 40-mL VOA vial.– Magnetic stir bar added to VOA vial

• The syringe was flushed with sample first.• Care was taken to minimize foaming during transfer.• Internal standards were added to vial with 5-mL DI

water at the autosampler.

Syringe used for sample transfer

Beverage Sample Preparation (cont.)

ColorlessCarbonated

Drink

PinkLemonade

OrangeSoda

DietCola

PineappleDrink

Cola

Instrument Conditions - Beverages

GC Agilent 6890N

Inlet 220°C, split 35:1

Column* Rtx-624, 30 m x 0.25 mm ID x 1.4 µm film, 0.8 mL/min column flow (He)

Oven 45°C (hold 4.3 min)12°C/min to 100°C (no hold)25°C/min to 250°C (hold 5.3 min)

MS Agilent 5975

Mode Scan, 35 to 260 amuSIM; m/z 78, 77, and 51

*Any standard VOC column can be used

VOCs in Consumer Beverages (cont.)

Diet ColaBenzene (7.2 min)

0.1 ppb

ColaBenzene (7.2 min)

0.1 ppb

Orange SodaBenzene (7.2 min)

0.1 ppb

Pineapple SodaBenzene (7.2 min)

0.2 ppb

VOCs in Consumer Beverages (cont.)

Iced Tea CitrusBenzene (7.2 min)

0.2 ppb

Pink LemonadeBenzene (7.2 min)

0.1 ppb

Root BeerBenzene (7.2 min)

0.7 ppb

Colorless Carbonated BeverageBenzene (7.2 min)

0.2 ppb

Details: Benzene in Root Beer

Results of NISTLibrary Search on

peak at RT 7.26 min

TIC

BenzeneRT = 7.26 min

• Benzene was detected in the root beer sample at a concentration of 0.7 ppb.

• The benzene was quantified using Fluorobenzene as the IS; the benzene quantitation ion was m/z 78.

• Compound identity was confirmed by comparison to a reference spectrum in the NIST Library.

EICP

0.7 ppb Benzene(m/z 78,77,and 51)

Fluorobenzene(IS)

Beverage Ingredients

Sodium Benzoate Citric Acid

Ascorbic Acid

Phosphate Benzoate

Potassium Benzoate

Phosphoric Acid

Pineapple Soda X X

Iced Tea Citrus X X X

Pink Lemonade X X

Orange Soda #1 X X X

Orange Soda #2 X X X

Colorless Carbonated Beverage #1 X X

Colorless Carbonated Beverage #2 X X

Cola #1 X

Cola #2 X

Diet Cola X X

Root Beer X X X

Summary: Benzene in Beverages

• Benzene was found in most of the consumer beverages at concentrations well below the USEPA 5-ppb limit for benzene in drinking water.

• MS Scan and SIM modes produced equivalent results.

• The model 4552 Water/Soil Autosampler was operated in the “Soil” mode to minimize foaming of the carbonated beverages.

• All beverage samples were analyzed using the Eclipse 4660 P&T Sample Concentrator.

Solid Sample Preparation

• Samples were frozen and either chopped or blended.

• Approximately 5 grams were weighed into 40-mL VOA vial with stir bar.

• The Model 4552 Water/Soil Autosampler was used to add Internal Standards with 5 mL water prior to purging.

Food Samples in VOA Vials

HotDogs

PotatoChips

Fast FoodBurger

PizzaCereal

Instrument Conditions – Table-Ready Food

GC Agilent 6890N

Inlet 200°C, split 10:1

Column* DB-VRX, 60 m x 0.25 mm ID x 1.4 µm film, 1 mL/min column flow (He)

Oven 35°C (hold 6 min)6°C/min to 175°C (no hold)10°C/min to 220°C (hold 2 min)

MS Agilent 5973

Mode Scan, 35 to 260 amu

*Any standard VOC column can be used, including 30- and 20-m columns

VOCs in Table-Ready Foods

Benzene (15.0 min)1.7 ppb

Breakfast CerealBenzene (15.0 min)

0.8 ppb

Hot Dogs


Potato ChipsBenzene (15.0 min)

1.7 ppb

Fast-Food Hamburger

VOCs in Table-Ready Foods (cont.)


Pepperoni PizzaBenzene (15.0 min)

Not Detected

Butter


Cheddar CheeseBenzene (15.0 min)

2.4 ppb

Ground Beef

VOCs in Table-Ready Foods (cont.)


Peanut ButterBenzene (15.0 min)

2.8 ppb

Strawberries


Diet Cola

Summary: Benzene in Table-Ready Food

• Benzene was found in most of the table-ready foods at concentrations ranging from ND in the Butter to 2.8 ppb in the Strawberries.– Slightly higher than in the beverages– There are no specified EPA or FDA standards for

benzene in table-ready foods• The model 4552 Water/Soil Autosampler was

operated in the “Soil” mode.• All of the samples were analyzed using the

Eclipse 4660 P&T Sample Concentrator.

Non-Food Consumer Products

• The same technique can be used to determine VOC content in non-food consumer products.

• Analytes of interest include flavor and fragrance compounds.

• Matrices that can be analyzed using this approach include toothpaste, shampoo, etc.

TIC of VOCs in 2.16 g Toothpaste

5.00 10.00 15.00 20.00 25.00 30.00 35.00 40.000

1000000

2000000

3000000

4000000

5000000

6000000

7000000

8000000

9000000

1e+07

1.1e+07

1.2e+07

1.3e+07

1.4e+07

1.5e+07

1.6e+07

1.7e+07

1.8e+07

1.9e+07

2e+07

2.1e+07

2.2e+07

2.3e+07

Time-->

Abundance

TIC: TTHPST02.D

Linalool

MentholMethyl

Salicylate

Anethole

Linalyl Acetate

Carvone

Selected Spectra From Toothpaste

20 30 40 50 60 70 80 90 1001101201301401501601701801902002100

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

Scan 4773 (29.168 min): SHMP001.D71 93

43 55

80121

136107

154 207

20 30 40 50 60 70 80 90 1001101201301401501601701801902002100

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

#114489: 1,6-Octadien-3-ol, 3,7-dimethyl-71

41

93

55

80

28121

105 136154

Linalool

40 60 80 100 120 140 160 180 200 220 240 2600

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

Average of 31.367 to 31.409 min.: TTHPST02.D9581

71

123

41 55138

109

207155 191170 253181

40 60 80 100 120 140 160 180 200 220 240 2600

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

#114614: Cyclohexanol, 5-methyl-2-(1-methylethyl)-, [1S-(1.a71

8141

9555

123138109

Menthol

20 40 60 80 100 120 140 160 180 200 220 240 2600

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

Average of 32.176 to 32.260 min.: TTHPST02.D120

92

152

65

3953

81 137109 207191177 253163 219 239

20 40 60 80 100 120 140 160 180 200 220 240 2600

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

#120911: Methyl Salicylate120

92

15239

65

532976 137

Methyl Salicylate

TIC of VOCs in 0.51 g Shampoo

5.00 10.00 15.00 20.00 25.00 30.00 35.00 40.000

1000000

2000000

3000000

4000000

5000000

6000000

7000000

8000000

9000000

1e+07

1.1e+07

1.2e+07

1.3e+07

1.4e+07

1.5e+07

1.6e+07

1.7e+07

1.8e+07

1.9e+07

2e+07

2.1e+07

2.2e+07

2.3e+07

2.4e+07

Time-->

Abundance

TIC: SHMP001.D

Ethyl-2-methyl Butyrate

LinaloolBenzyl Acetate

Selected Spectra From Shampoo

Ethyl-2-Methyl Butyrate

10 20 30 40 50 60 70 80 90 100 110 120 1300

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

Average of 19.380 to 19.475 min.: 10MLWTR.D71

43

88

60

10111637 53 80 127

10 20 30 40 50 60 70 80 90 100 110 120 1300

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

#24311: Butanoic acid, ethyl ester7143

29 88

60

10115 11637

Linalool

20 30 40 50 60 70 80 90 1001101201301401501601701801902002100

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

Scan 4773 (29.168 min): SHMP001.D71 93

43 55

80121

136107

154 207

20 30 40 50 60 70 80 90 1001101201301401501601701801902002100

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

#114489: 1,6-Octadien-3-ol, 3,7-dimethyl-71

41

93

55

80

28121

105 136154

Benzyl Acetate

20 40 60 80 100 120 140 160 180 200 220 2400

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

Scan 5118 (30.980 min): SHMP001.D108

91

150

7943

65

20754 135121 167 191 253180

20 40 60 80 100 120 140 160 180 200 220 2400

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

#119765: Acetic acid, phenylmethyl ester108

9143

15079

65

15 27 54 135121

TIC of VOCs in 10 mL Flavored Water

6.00 8.0010.0012.0014.0016.0018.0020.0022.0024.0026.0028.0030.0032.000

1000000

2000000

3000000

4000000

5000000

6000000

7000000

8000000

9000000

1e+07

1.1e+07

1.2e+07

1.3e+07

1.4e+07

1.5e+07

1.6e+07

1.7e+07

1.8e+07

Time-->

Abundance

TIC: 10MLWTR.D

Ethyl Butyrate

cis-3-Hexenol

Citral (Z)

Citral

Selected Spectra From Flavored Water

Ethyl butyrate

10 20 30 40 50 60 70 80 90 100 110 120 1300

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance


43

88

60

10111637 53 80 127

10 20 30 40 50 60 70 80 90 100 110 120 1300

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

#24311: Butanoic acid, ethyl ester7143

29 88

60

10115 11637

cis-3-Hexenol

20 30 40 50 60 70 80 90 1001101201301401501601701801902002100

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance


41

82

55

100 115 141 207

20 30 40 50 60 70 80 90 1001101201301401501601701801902002100

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

#108738: 3-Hexen-1-ol, (Z)-41

67

5582

31

100

Citral

40 60 80 100 120 140 160 180 200 220 240 2600

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance


41

84

94109 13753 123

152207191177 253163

40 60 80 100 120 140 160 180 200 220 240 2600

1000

2000

3000

4000

5000

6000

7000

8000

9000

m/z-->

Abundance

#114142: 2,6-Octadienal, 3,7-dimethyl-69

41

84

9453 137109 123

152

Summary: VOCs in Non-Food Products

• The VOCs detected in the non-food consumer products were primarily flavor and fragrance compounds.– Identification by comparison to NIST Library spectra

• The model 4552 Water/Soil Autosampler was operated in the “Soil” mode.

• All of the samples were analyzed using the Eclipse 4660 P&T Sample Concentrator.

Conclusion

• The Model 4660 Eclipse P&T Sample Concentrator and Model 4552 Water/Soil Autosampler can be used to test for low levels of benzene and other VOCs in beverages, table-ready foods, and non-food consumer products.

• All of the beverage and food samples tested for this project were either ND for benzene or contained benzene at concentrations below the USEPA water quality level of 5 ppb.

• For information on the Eclipse P&T Sample Concentrator and the 4552 Water/Soil Autosampler, contact your OI Account Representative or call 979-690-1711.

Publication Number 2658

analysis of benzene and other vocs in consumer beverages ... · analysis of benzene and other vocs...

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