1,1,2,2-TETRACHLOROETHANE
MW: 167.85
Cl2 CHCHCl2 METHOD: 2562, Issue 1
CAS: 79-34-5
RTECS: KI8575000
EVALUATION: PARTIAL
OSHA : 5 ppm (skin) NIOSH: 1 ppm; carcinogen; Group I Pesticide ACGIH: 1 ppm
2562
PROPERTIES:
Issue 1: 15 March 2003
liquid; d 1.586 g/mL @ 25 °C; BP 146.5 °C; MP G 44 °C; VP 0.8 kPa (6 mm Hg; 0.8% v/v) @ 25 °C; nonflammable
(1 ppm = 6.86 mg/m3 @ NTP)
SYNONYMS: acetylene tetrachloride; bonoform; 1,1-dichloro-2,2-dichloroethane
SAMPLING SAMPLER:
SOLID SORBENT TUBE (Anasorb CMS; 100/50 mg)
FLOW RATE:
0.01-0.2 L/min
VOL-MIN: -MAX:
3 L @ 5 ppm 30 L
SHIPMENT:
Routine
SAMPLE STABILITY:
28 days at 25 °C
BLANKS:
2 to 10 field blanks per set
MEASUREMENT TECHNIQUE:
GAS CHROMATOGRAPHY, FID
ANALYTE:
1,1,2,2-tetrachloroethane
DESORPTION:
1 mL CS2 ; stand 30 min
INJECTION VOLUME:
1 µL
TEMPERATURE -INJECTION: 250 °C -DETECTOR: 300 °C -COLUMN: 40 °C (1 min), 10 °C/min to 175 °C CARRIER GAS:
He, 2.8 mL/min
COLUMN:
Capillary, fused silica, 30 m x 0.32mm ID, 1.0-µm film, 100% dimethyl polysiloxane or equivalent
CALIBRATION:
Standard solutions of analyte in CS 2
OVERALL PRECISION (Ö r T ): Not determined
RANGE:
2.1 to 285.5 µg per sample [1]
ACCURACY:
ESTIMATED LOD: 0.6 µg per sample [1]
ACCURACY RANGE STUDIED:
Not studied
BIAS:
Not determined
Not determined
PRECISION ( þ r ):
1.6% @ 38.1 to 253.8 µg per sample [1]
APPLICABILITY: The working range is 0.031 to 4.17 ppm (0.21 to 28.6 mg/m3 ) for a 10-L air sample [1].
INTERFERENCES: Any compound with a similar retention time under these analytical conditions is considered to be an interference.
OTHER METHODS: This method updates NIOSH Method 1019 [2] through the use of a capillary column, incorporation of Anasorb CMS sorbent tubes, and lowered sampling and analytical range with accompanying lower LOD/LOQ values [1].
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition 1,1,2,2-TET RAC HLO RO ETH ANE : MET HO D 256 2, Issue 1, dated 15 M arch 200 3 - Page 2 o f 4 REAGENTS:
EQUIPMENT:
1. Carbon disulfide (CS 2), chrom ato graphic qua lity.* 2. 1,1,2,2-T etrac hloroetha ne, re age nt gra de.* 3. Desorption efficiency (DE) stock solution, 12.7 mg/mL. Dilute 80 µL of 1,1,2,2-tetrachloroethane to 10 mL with CS 2. 4. Helium, purified 5. Hydrogen, prepurified 6. Air, filtered, compressed
1. Sam pler: glass tube, 7 cm long, 6-mm OD, 4-m m ID, glass-sealed ends with plastic caps, containing two sections of 100/50 An asorb CMS (front = 100 mg; back = 50 mg) separated by a 2-m m glass wool plug. Another glass wool plug precedes the front section and a 3-mm urethane foam plug follows the back section. (SKC 226121, or equivalent). 2. Personal sa m pling pum p, 0.01 to 0.2 L/m in, with flexible connecting tubing. 3. Gas chrom atograph, flam e ionization detector, integrator, and column. 4. Vials, 2-mL, PTFE-lined caps. 5. Syringes, 10-µL, rea dab le to 0.1 µL, 25-µL, read able to 0.5 µ L, and 10 00-µ L, rea dab le to 1 µL. 6. Volumetric flasks, 10-mL. 7. Pipet, TD, 1-mL.
- See SPECIAL PRECAUTIONS
SPE CIAL PRECAUTIONS: 1,1,2,2-Tetrachloroethane is a powerful narcotic, liver poison, and suspected carcinogen, and can be abso rbed throu gh the sk in [3, 4]. Carbon disulfide is toxic and a serious fire and explosion hazard (flash point = - 30 °C). W ork with these substances only in a hood. SAMPLING: 1. 2. 3. 4.
Calibrate each personal sampling pump with a representative sampler in line. Break ends of the sampler imm ediately before sampling. Attach sampler to personal sampling pump with flexible tubing. Sam ple at a n ac curately kn own flow ra te betwee n 0.01 an d 0.2 L/m in for a total sam ple size of 3 to 30 L. Ca p the sam plers. Pac k secu rely for shipm ent.
SAMPLE PREPARATION: 5. 6. 7.
Place front and back sorbent sections of the sampler tube in separate vials. Discard glass wool plugs. Add 1.0 mL CS 2 to each vial. C ap each vial. Allow to stand 30 min with occasional agitation.
CALIBRATION AND QUALITY CONTRO L: 8.
9.
Calibrate daily with at least six working standards from below the LOD to 10x the LOQ. a. Add a specific amount of 1,1,2,2-tetrachloroethane to CS 2 in 10-m L volum etric flas ks and dilute to th e m ark. Us e serial dilutions as needed to obta in 1,1,2 ,2-tetrachloroeth ane concentratio ns in the ran ge needed. Additional standards m ay be added to exte nd the calibra tion curve , if necess ary. b. Analyze with calibration standards, sam ples, and blanks (s teps 11 and 12). c. Prepare c alibration graph (pe ak area vs. µg 1,1,2,2-tetrachloroethane). Determine desorption efficiency (DE) at least once for each lot of sorbent used for sampling in the range of interest. Prepare three tubes at each of five concentrations plus three media blanks. a. Rem ove and disca rd back sorbent sec tion of a med ia blank sam pler. b. Injec t a kn own am oun t (2 to 25 µL ) of D E sto ck solution, or a serial dilution thereof, directly onto the front sorbent section with a microliter syringe. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition 1,1,2,2-TET RAC HLO RO ETH ANE : MET HO D 256 2, Issue 1, dated 15 M arch 200 3 - Page 3 o f 4
10.
c. Cap the tube. Allow to stand for 24 hours. d. Deso rb (steps 5 through 7 ) and analyze with working standards (steps 11 and 12). e. Prepare a graph of DE vs. µg 1,1,2,2-tetrachloroethane recovered. Analyze three quality control blind spikes and three analyst spikes to ensure that the calibration graph and DE graph are w ithin the lim its set b y the qu ality assu ranc e po licy and a re co nsistent with the results given in the section entitled “Evaluation of Method”.
MEASUREMENT: 11.
12.
Set gas chromatograph according to manufacturer’s recomm endations and to conditions given on page 25 62-1. Inject sam ple aliquot m anually using solvent flush techn ique or with an autosam pler. NOTE: If peak area is above the linear range of the working standards, dilute an aliquot of the desorbed liquid with CS 2, reanalyze and apply the appropriate dilution fa cto r in calculations. Measure peak area.
CALCULATIONS: 13.
14.
De term ine the m ass , :g (corrected for DE) of 1,1,2,2-tetrachloroethane found in the sample front (W f) and back (W b) sorbent sections an d in the average m edia blank front (B f) and back (B b) sorbent sections. NO TE: If W b > W f/10, report breakthrough and possible sample loss. Calculate conce ntration, C, of 1,1,2,2-tetrachloroethane in the air volume sam pled, V (L):
NO TE : :g/L / m g/m 3
EVALUATION OF METHOD: NMAM 1019, Issue 1 and Issue 2: The 4 th edition Method 1019 is 2 nd edition NMAM Method S124 in the 4 th edition format . Method S124 was issued on May 9, 1975 [5], and validated with generated atmospheres which were calibrated by gas chromatography [6]. Average recovery was 106 % at 5 pp m . Breakthrough did not occur after sampling 4 h at 0.185 L /m in from an atm osp here con taining 101 m g/m 3 in dry air. Desorption efficiency for SKC Lot 104 petroleum-based charcoal was 0.83, 0.87, and 0.88 at 160, 320, and 640 µg 1,1,2,2-tetrachloroethane per sample, resp ective ly. Lower recoveries w ere o bse rved for coco nut shell charcoal (S KC Lot 105). In subsequent work, 1,1 ,2,2 -tetrachloroethane was observed to degrade rapidly into trichloroethylene during storage on Pittsburgh activated carbon: 19% converted during one day and 63% converted during eight days at ambient conditions [7]. Therefore, the analyte is sensitive to the sorbent type; only the recomm ended sorbent sh ould be used. B reak through at high rela tive hum idity w as not tes ted , nor was sam ple sta bility. NMAM 2562, Issue 1 Initial work to update the NMAM method 1019 resu lted in an average reco very of 88.4% over a ran ge o f 38.1 to 253 .8 µg from the petroleum cha rcoal [1]. In order to see if the overall desorption efficiency of 1,1,2,2tetrachloroethane could be improved at these lower levels, the sorbent was changed from petroleum charcoal to Anaso rb CM S. Deso rption efficiency using Ana sorb CMS (SKC Lot 1879) was 91, 85, 88, and 91% at 38, 76, 165, and 254 µg 1,1,2,2-tetrachloroethane per sample, respectively. The limit of detection was found to be 0.6 µg per sam ple. A recovery of 87% was obtained at a level of 165 µg a fter storage for 28 days at am bient conditions [1].
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition 1,1,2,2-TET RAC HLO RO ETH ANE : MET HO D 256 2, Issue 1, dated 15 M arch 200 3 - Page 4 o f 4 REFERENCES: [1] Boss e RA , Pendergras s SM [2001]. 1,1,2,2-Tetrachloroethane Ba ckup Data R eport, Novem ber. [2] NIOSH [1994]. 1,1,2,2 Tetrachloroethane: Method 1019. In Eller PM, Cassinelli ME, eds. NIOSH Manual of Analytical Methods 4 th ed. Cincinnati, OH: U.S. Departmen t of H ealth and H um an Servic es, Pu blic He alth Service, Centers for D isease C ontro l and P reve ntion, N ationa l Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 94-113. [3] NIOSH [1976]. NIOSH criteria for a recomm ended standard: occupational exposure to 1,1,2,2tetrachloroethane. Cin cinnati, OH : U.S. Departm ent of He alth, Ed uca tion an d W elfare , Pub lic Health Services and Mental Health Adm inistration , National Ins titute for Occupational Safety and Health, DHEW (NIOSH) Publication No. 77-1216), available as PB 273-802 from NT IS, Springfield, VA 22161. [4] NIOSH/OSHA Occupation Health Guidelines for Chemical Hazards, U.S. Department fo Health and Hum an Services, Publ. (NIOS H) 81-12 3 (1981), available as Stock #PB83-154609 from NT IS, Springfield, VA 22161. [5] NIOSH Ma nua l of Analytical Metho ds, 2 nd ed., Vol. 2, S124, U.S. Department of Health, Education, and W elfare, Publ. (NIOSH) 77 -157-B (197 7). [6] Docum entation of the NIOSH Validation Tests, S124, U.S. Department of Health, Education, and W elfare, Publ. (NIOSH) 77-185 (1977), available as Stock No. PB 274-248 from NTIS, Springfield, VA 22161 [7] Arnold, J. Internal mem o (NIOSH, unpublished, May 8, 1984)
METHOD WRITTEN BY: Rebecca A. Bosse and Stephanie M. Pendergrass, NIOSH, DART
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition