Glycol Ethers (2554)
GLYCOL ETHERS (1) CH3 OCH2 CHOHCH3 MW: 90.1 (2) CH3 OC3 H6 OC3 H6 OH 148.2 (3) CH3 OCH2 CH(CH3 )COOCH3 132.16 METHOD: 2554
2554
CAS: 107-98-2 34590-94-8 108-65-6
RTECS: UB7700000 JM1575000 AI8925000
EVALUATION: PARTIAL PROPERTIES:
OSHA : See Table I NIOSH: See Table I ACGIH: See Table I
Issue 1: 15 March 2003 See Table I
SYNONYMS: (1) propylene glycol monomethyl ether, 1-methoxy-2-propanol, 2-methoxy-1-methylethanol, propylene glycol methyl ether (2) dipropylene glycol monomethyl ether (3) propylene glycol monomethyl ether acetate, propylene glycol methyl ether acetate, 1-methoxy-2-propyl acetate SAMPLING SAMPLER:
FLOW RATE:
SOLID SORBENT TUBE (Anasorb® 747, 140 mg/70 mg)
3L 25 L (at lower flow rates)
SHIPMENT:
Keep cold, pack securely for shipping
BLANKS:
TECHNIQUE:
GAS CHROMATOGRAPHY, FID
ANALYTE:
See Table I
DESORPTION:
1 mL of methylene chloride/methanol (85:15) for 30 minutes in ultrasonic bath
0.1 to 0.2 L/min
VOL-MIN: -MAX:
SAMPLE STABILITY:
MEASUREMENT
INJECTION VOLUME:
1 :L
14 days @ 5°C for analytes 1 and 3; 7 days @ 5°C for analyte 2
TEMPERATURE -INJECTION: 195°C -DETECTOR: 240°C -COLUMN: 90°C (1 min) to 200°C (10°C/min)
2 to 10 field blanks per set
CARRIER GAS:
Helium, 2.8 mL/min
COLUMN:
Capillary, fused silica, 30 m x 0.32-mm ID; 100% PEG-DA, Stabilwax or equivalent
CALIBRATION:
Solutions of analytes in desorption solvent
RANGE:
(1) 1.5 to 369 :g[3] (2) 3.0 to 375 :g[3] (3) 1.5 to 369 :g[3]
ACCURACY RANGE STUDIED:
Not determined.
BIAS:
Not determined.
OVERALL PRECISION (Ö r T ):
Not determined.
ACCURACY:
Not determined
ESTIMATED LOD: (1) 0.5 :g[3] (2) 1.0 :g[3] (3) 0.5 :g[3] PRECISION ( þ r ):
(1) 0.013[3] (2) 0.031[3] (3) 0.016[3]
APPLICABILITY: The working range for propylene glycol monomethyl ether was 0.041 to 10.0 ppm (0.154 to 36.9 mg/m3 ), for dipropylene glycol monomethyl ether was 0.050 to 6.19 ppm (0.305 to 37.5 mg/m3 ), and propylene glycol monomethyl ether acetate was 0.030 to 6.83 ppm (0.151 to 36.9 mg/m3 ) for a 10 L sample . Other methods used for the collection of these analytes used a different solid sorbent and were evaluated at higher analyte concentrations [1,2]. Collection and DE recovery at levels greater than the working range listed should be equal or better than those achieved using charcoal sorbent tubes. INTERFERENCES: No specific interferences were identified. However, any compound with a similar retention time as the analytes of interest may interfere. OTHER METHODS: OSHA method 99 [1] and OSHA method 101 [2] can also be used for sampling glycol ethers at or above the REL and PEL. NIOSH Method S69, from the 2nd edition of the NIOSH Manual of Analytical Methods, was used previously for the collection and analysis of dipropylene glycol monomethyl ether and had acceptable recovery at a concentrations at or above the REL/PEL [4].
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition GLY CO L ET HER S: ME TH OD 2554, Issue 1, dated 1 5Ma rch 2003 - Page 2 of 4 REAGENTS:
EQUIPMENT:
1. Propylene glycol m ono m ethyl ethe r, reag ent grad e.* 2. Dipropylene glycol monomethyl ether, reagent grad e.* 3. Propylene glycol monomethyl ether acetate, reag ent grade .* 4. Me thylene chloride, chrom atographic gra de.* 5. Me than ol, chrom atog raph ic grade.* 6. Desorbing solution, 15% m ethanol in 85% m ethylene chloride (V/V). 7. Propylene glycol monomethyl ether calibration stock solution, 46.2 mg/m L. Dilute 0.5 mL analyte to 10 mL with desorbing solution. 8. Dipropylene glycol monomethyl ether calibration stock solution, 47.5 mg/m L. Dilute 0.5 mL analyte to 10 mL with desorbing solution. 9. Propylene glycol m ono m ethyl ethe r ace tate calibra tion sto ck solution, 48.5 m g/m L. Dilute 0.5 mL nitrobenzene to 10 mL with desorbing solution. 10. Air, compressed, purified, and filtered. 11. Helium, purified and filtered. 12. Hydrogen, filtered.
1. Sam pler: glass tube, 7 cm long, 6-mm OD, 4mm ID, flame-sealed ends, containing two sections of Anasorb® 747 (140mg/70 mg) sep arate d by a 2 -m m ureth ane foam plug. A silylated glass wool plug precedes the front section. A urethane foam plug follows the back sectio n. T ubes are com m ercially available from SKC, Inc. 2. Personal sampling pump, 0.1 to 0.2 L/min, connected with flexible tubing. 3. Gas chrom atograph, FID, integrator, and 30-m Stabilwax-DA or equivalent capillary column (page 255 4-1). 4. Vials, autosampler, with PTFE-lined caps. 5. Syringes, 10-:L, 25-:L, and 1-mL. 6. Volumetric flasks, 10-mL. 7. Refrigerant packs for shipping.
- See SPECIAL PRECAUTIONS
SPECIAL PRECAUTIONS: Methylene chloride is a carcinogen [3]. Methanol is very flamm able and toxic. Glycol ethers are irritants and hazardous compounds. W ear appropriate protective clothing and work with these compounds in a well-ventilated hood. SAMPLING: 1. Ca librate each pers ona l sam pling pum p with a represe ntative sam pler in line. 2. Break the ends of the sampler imm ediately prior to sampling. Attach sampler to personal sampling pump with flexible tubing. 3. Sam ple at an accurately known flow rate between 0.1 and 0.2 L/min for a total sample size of 10 L. 4. Cap the samplers with plastic (not rubber) caps and pack securely for shipment. Samples should be kept cold.
SAMPLE PREPARATION: 5. Place the front and back sorbent sections of the sampler tube in separate vials. Place the glass wool preceding the front section into the vial containing the front section. Discard the remaining foam plugs. 6. Ad d 1.0 m L of the desorbing solution into each vial. Attach crim p caps to each vial. 7. Plac e the sam ple vials in an u ltrasonic ba th for 3 0 m inutes .
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition GLY CO L ET HER S: ME TH OD 2554, Issue 1, dated 1 5Ma rch 2003 - Page 3 of 4 CALIBRATION AND QUALITY CONTRO L: 8. Calibrate daily with at least s ix workin g stan dards to cover the analytica l ran ge. If necessary, additional standards may be added to extend the calibration curve. a. Add known amounts of analytes to solvent solution in 10-mL volumetric flasks and dilute to the m ark. Mix well. b. Analyze together with samp les and blanks (steps 11 and 12). c. Prepare calibration graph (peak area versus :g an alyte). 9. Dete rm ine desorption efficiency (DE) at least once for each lot of Anasorb 747 used fo r sam pling in the calibration ranges (step 8). a. Prepare three tubes at each of five levels plus three media blanks. b. Inject a known amount of calibration stock solution directly onto the front sorbent section of each Anasorb 747 tube with a microliter syringe. c. Allow the tub es to air equ ilibrate for several m inutes , then cap the ends of ea ch tube a nd a llow to stan d overnight. d. Deso rb (steps 5-7) and a nalyze together with standards and blanks (steps 11 and 12). e. Prepare a graph of DE versus :g analyte recovered. 10. Analyze three quality control blind spikes and three analyst spikes to ensure that the calibration graph and D E graph are in control.
MEASUREMENT: 11. Set gas chromatograph according to manufacturer’s recomm endations and to conditions given on page 2554-1. Inject a 1-:L sample aliquot manually using the solvent flush technique or with an autosam pler. NOTE: If pea k area is abo ve the linear ra nge of the working standard s, dilute w ith solve nt, reanalyze and apply the appropriate dilution factor in the calculations. 12. Measure peak areas.
CALCULATIONS: 13. De term ine the m ass , :g (corrected for D E) of analyte found in the sam ple front (W f) and back (W b) sorbent sec tions, and in the average m edia blank front (B f) and back (B b) sorbent sections. NOTE: If W b > W f/10, report b reak throu gh a nd p oss ible sam ple loss. 14. Calculate conce ntration, C, of analyte in the air volume sam pled, V(L):
NO TE : :g/L = m g/m 3
EVALUATION OF METHOD: In order to obtain improved analyte collection and recove ry results, several procedures were incorporated in the m etho d de velop m ent. These included the use of a s tain less stee l inlet liner in the injection port to reduce the possibility of degradation of analytes, lower injection port and detector temperatures to prevent thermal decomposition of a nalytes, and the use of Anasorb 747 solid sorbent tubes to reduce the possibility of the hydrolysis of the analytes. This m eth od was developed in support of a fie ld survey to iden tify and quan titate glycol ether vapors emitted from heat-cured solder mask paints. This method is applicable when levels below the REL/PEL are expected. The average desorption efficiency (DE) recovery for propylene glycol monomethyl ether was 100.6% (RSD = 1.6), for dipropylene glycol monomethyl ether, was 102.4% (RSD = 1.8), and for propylene glycol
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition GLY CO L ET HER S: ME TH OD 2554, Issue 1, dated 1 5Ma rch 2003 - Page 4 of 4 mon om ethyl ether acetate was 102.0% (RSD = 1.7). The average 14-day storage stability recovery at approxim ate ly 75x the LOQ for propylene glycol monom ethyl ether was 103.1% (RSD = 2.1), for dipropylene glycol monom ethyl ether was 77.7% (RSD = 2.3), and propylene glycol m onom eth yl ether acetate was 95.4% (RSD = 3.7). Samples containing dipropylene glycol monomethyl ether should be analyzed soon after collection to minimize sample loss during storage.
REFERENCES: [1]
[2]
[3] [4] [5]
OSHA [1993]. Propylene Glycol Monomethyl Ethers/Acetate, Method 99. Organic Methods Evaluation Branch, OSHA A nalytical Methods Manual. Salt Lake City, UT: U.S. Department of Labor, O ccupa tional Safety and He alth Adm inistration, OSH A Salt Lake T echnical Cen ter. OSHA [1993]. Dipropylene Glycol Methyl Ether, Method 101. Organic Methods Evaluation Branch, OSHA Analytical Methods Manual. Salt Lake City, UT: U.S. Department of Labor, Occupational Safety and He alth Adm inistration, OSH A Salt Lake T echnical Cen ter. Pendergrass SM [1998]. Backup data report for glycol ethers. Unpublished report. NIOSH/DPSE. NIOSH [1977]. Docum entation of the NIOSH Validation Tests, S69, U.S. Department of Health, Educa tion, and W elfare; Publ. (NIOSH ) 77-185 (197 7). NIOSH Recom mendations for Occupational Safety and Health, U.S. Department of Health and Hum an Services, (NIO SH) P ubl. 92-100 (Janua ry 1992).
METHOD WRITTEN BY: Stephanie M. Pendergrass, NIOSH/DPSE
TABLE 1.
EXPOSURE LIMITS AND PHYSICAL PROPERTIES
Analyte
OSHA PEL (p pm )
NIOSH REL (p pm )
ACG IH TLV (ppm )
mg/m 3 = 1 ppm @ NTP
Physical Properties
Propylene glycol monom ethyl ether
None
100
100
3.75
Liquid; d 0.9234 g/mL @ 20 °C, BP 120.1 °C, VP 1.6 kPa (12 mm Hg) @ 20°C
Dipropylene glycol monom ethyl ether
100
100
100
6.16
Liquid; d 0.9500 g/mL @ 20 °C, BP 189.6 °C, VP 0.05 kPa (0.5 mm Hg) @ 20°C
Propylene glycol monom ethyl ether ace tate
None
None
None
5.40
Liquid; d 0.9700 g/mL @ 20 °C, BP 145.8 °C, VP 0.5 @ 20°C KPa
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition