Chemical Pollutants in Air, Water, Soil, and Solid Wastes Phần 7 pdf

ANALYSIS OF AQUEOUS AND NONAQUEOUS SAMPLES Purge and trap method; ethylbenzene transferred from aqueous to vapor phaseunder helium purge; analyte adsorbed on a sorbent trap; thermally de

Synonym: phenylethane; Formula C8H10; Structure:

MW 106.18; CAS [100-41-4]; used as a solvent and an intermediate to produce styrene monomer; colorless liquid; characteristic aromatic odor; boils at 136°C; vapor pressure 7.1 torr at 21°C; freezes at –95°C; density 0.86 g/mL at 20°C; solubility in water 0.015 g/100 g; readily miscible with organic solvents.

ANALYSIS OF AQUEOUS AND NONAQUEOUS SAMPLES

Purge and trap method; ethylbenzene transferred from aqueous to vapor phaseunder helium purge; analyte adsorbed on a sorbent trap; thermally desorbedout from the sorbent trap backflushed with He onto a GC column for separationfrom other volatile compounds; determined by PID, FID or a mass spectrometer.Solid samples mixed with methanol; a portion of methanol extract spiked into ameasured volume of water (25 mL) in the purging vessel; subjected to purgeand trap concentration and analyzed as above

Alternatively, ethylbenzene thermally desorbed from the solid sample under Hepurge (without any solvent treatment) onto the GC column and analyzed on asuitable detector or by a mass spectrometer as above

detected by PID

SPB-5, VOCOL, DB-624, or equivalent; packed column: 1% SP-1000 on bopack B (60/80 mesh) or equivalent

3.33

350 HANDBOOK OF ENVIRONMENTAL ANALYSIS

1,4-difluo-robenzene (m/z 114, 63,88)

analyzed within 7 days Samples preserved with 1:1 HCl (0.2 mLacid/40 mL sample) may be analyzed in 14 days

AIR ANALYSIS

Air drawn through a sorbent tube packed with coconut shell charcoal (100 mg/50

analyzed by GC-FID (NIOSH Method 1501, 1984); recommended air flow rate

100 mL/min; sample volume 20 L

W-AW, Porapak P (50/80 mesh), or equivalent

Alternatively, air collected in a SUMMA passivated stainless steel canister either

by pressurizing the canister using a sample pump or by preevacuating; canisterthen connected to an analytical system; air transferred to a cryogenically cooledtrap; cryogen removed and temperature raised; analyte revolatilized; separated

on a GC column; determined by PID, FID, or a mass spectrometer (U.S EPAMethod TO-14, 1988)

Alternatively, air drawn through a cartridge packed with either Tenax (1 g) orcarbon molecular sieve (0.5 g); cartridge heated at 350°C under helium purge;analyte transported to the front of a precooled GC column, temperature pro-grammed; ethylbenzene determined on a PID, FID, or a mass spectrometer;recommended air flow rate 0.5 L/min; sample volume 50 L

(1 ppm ethylbenzene in air = 4.34 mg/m3 at NTP)

© 1997 by CRC Press LLC

© 1997 by CRC Press LLC

ETHYL CHLORIDE

Synonym: chloroethane; Formula: C2H5Cl; MW 64.52; CAS [75-00-3]; colorless gas at room temperature with ether-like odor; liquefies at 12.5°C; slightly soluble in water, miscible with organic solvents

ANALYSIS OF AQUEOUS SAMPLES

Aqueous samples subjected to purge and trap extraction; volatile analyte thermally desorbed out from the trap on heating and swept onto a GC column for sepa-ration; detected by HECD, ECD, or MDS; low retention time

• Characteristic masses for GC/MS identification: 64 and 66

• Limit of detection: in the range 0.1 µg/L when detected by HECD for a 5-mL sample aliquot (subject to matrix interference)

• Recommended surrogate/IS: bromochloromethane and ethane-d4

1,2-dichloro-• Samples collected in glass/plastic containers without headspace, ated, and analyzed within 14 days

refriger-See Halogenated Hydrocarbons, Chapter 2.9, for GC columns and conditions and

a detailed discussion

AIR ANALYSIS

The following methods are recommended:

Adsorbed over carbon molecular sieve (~400 mg); desorbed at 350°C into a cryogenically cooled trap; flash evaporated onto a capillary column GC/MS system; recommended sample volume 10 L; flow rate 100 mL/min

Collected in SUMMA passivated canister or a liquid argon trap; transferred onto a precooled GC column; determined by ECD or MSD

3.34

ETHYLENE CHLOROHYDRIN

Synonyms: 2-chloroethanol, 2-chloroethyl alcohol; Formula: C2H5OCI; Structure: Cl–CH2–CH2–OH; MW 80.52; CAS [107-07-3]; used as a solvent for cellulose esters and in making ethylene glycol and ethylene oxide; colorless liquid with a faint ether odor; boils at 129°C; freezes at –67°C; density 1.197 g/mL at 20°C; soluble in water, alcohol, and ether; highly toxic.

ANALYSIS OF AQUEOUS SAMPLE

Purge and trap concentration; sample purged with He under heating; analytedesorbed from the trap by heating and backflushing with He; transferred onto

a GC column for separation; determined by GC-FID or a mass spectrometer

Purging vessel should be heated under He purge

AIR ANALYSIS

Air drawn through a solid sorbent tube containing petroleum charcoal

30 min standing) and analyzed by GC-FID (NIOSH Method 2513, 1985);recommended flow rate 0.1 L/min; sample volume 20 L

(1 ppm ethylene chlorohydrin in air = 3.29 mg/m3 at NTP)

3.35

ETHYLENE DIBROMIDE

Synonyms: 1,2-dibromoethane, EDB; Formula: BrCH2CH2Br; MW 187.88; CAS [106-93-4]; used in fumigant and antiknock gasolines; colorless heavy liquid; chloroform odor; boils at 131°C; freezes at 10°C; vapor pressure 11 torr

at 20°C; density 2.7 g/mL at 25°C; slightly soluble in water (0.4%); miscible with alcohol and ether; irritant and toxic.

ANALYSIS OF AQUEOUS AND NONAQUEOUS SAMPLES

Purge and trap method; aqueous samples purged with He; EDB thermally desorbedfrom the sorbent trap and swept by an inert gas onto a GC column for separationfrom other volatile compounds; analyzed by a halogen-specific detector or amass spectrometer

Solid samples mixed with methanol; methanol extract spiked into water; aqueoussolution subjected to purge and trap extraction and analyzed as above

or equivalent

analyzed within 7 days

AIR ANALYSIS

Air drawn through a sorbent tube containing coconut shell charcoal(100 mg/50 mg); EDB desorbed from the charcoal by treatment with 10 mL99:1 benzene-methanol (allowed to stand for 1 h); the solvent extract analyzed

by GC-ECD (NIOSH Method 1008, 1987); recommended flow rate

100 mL/min; sample volume 10 L

3.36

Air collected in a SUMMA passivated canister under pressure using an additionalpump or at subatmospheric pressure by initially evacuating the canister;sample transferred into a cryogenically cooled trap attached to a GC column;the trap heated; EDB separated on the GC column and determined by a massspectrometer (U.S EPA Method TO-14)

(1 ppm EDB in air = 7.68 mg/m3 at NTP)

© 1997 by CRC Press LLC

© 1997 by CRC Press LLC

ETHYLENE GLYCOL

Synonym: 1,2-ethanediol; Formula: HOCH2CH2OH; MW 62.07; CAS 21-1]; used as antifreeze in cooling and heating systems and in hydraulic brake fluids; colorless liquid; sweet taste; hygroscopic; density 1.11 g/mL; boils at 197.5°C; freezes at –13°C; highly soluble in water, lower alcohols, acetone, and pyridine; toxic.

[107-ANALYSIS OF AQUEOUS AND NONAQUEOUS SAMPLES (SUGGESTED METHOD)

Aqueous samples directly injected onto a GC column and determined by an FID

10, Nukol, or equivalent

10 g soil, sediment, or solid wastes sonicated with 50 mL 2% isopropanol in water;extract injected onto GC column; determined on FID

AIR ANALYSIS

Air drawn through a glass fiber filter and then through a sorbent tube containingsilica gel (520 mg/260 mg), ethylene glycol desorbed out from silica gel with2% isopropanol in water (on 5-min standing); the analyte in eluant determined

by GC-FID (NIOSH Method 5500, 1984); recommended air flow rate0.2 L/min; sample volume 30 L

Chromosorb 101 Any appropriate polar column may be used

3.37

Alternatively, air bubbled through water; aqueous soln of the analyte oxidizedwith periodic acid into formaldehyde; the latter analyzed by chromotropic acidcolorimetric method (Tucker and Deye, 1981)

(1 ppm ethylene glycol in air = 2.54 mg/m3 at NTP)

© 1997 by CRC Press LLC

© 1997 by CRC Press LLC

ETHYLENE OXIDE

Synonyms: 1,2-epoxyethane, oxirane; Formula: C2H4O; Structure:

MW 44.06; unstable, ring cleaves readily; CAS [75-21-8]; used as a fumigant and sterilizing agent, and in the manufacture of many glycol ethers and ethano- lamines; colorless gas with ether-like odor; liquefies at 10.4°C; density 0.88 g/mL

at 10°C; vapor pressure 1095 torr at 20°C; soluble in water and most organic solvents; highly flammable, toxic, and severe irritant.

AIR ANALYSIS

Air drawn through a solid sorbent tube containing HBr-coated petroleum charcoal;bromo derivative of analyte formed desorbed with dimethylformamide (DMF)and analyzed by GC-ECD (NIOSH Method 1614, 1987); recommended airflow 100 mL/min; sample volume 10 L

converted into ethylene glycol; latter measured by GC-FID (Romano andRenner, 1979)

employed in air sampling; glycol formed desorbed with water or a suitableorganic solvent analyzed by GC-FID

technique (Pritts et al., 1982) Air is drawn through a multipart detector tubeconsisting of three reactor tubes: containing periodic acid, xylene, and conc

O

3.38

which then reacts with xylenes to form diaryl methylene compounds The latter

compounds Thus, the color in the detector tube changes from white to reddishbrown and the concentration of the analyte in the range 5 to 1000 ppm may bemonitored from the length of stain formed in the detector tube

(1 ppm ethylene oxide in air = 1.80 mg/m3 at NTP)

© 1997 by CRC Press LLC

© 1997 by CRC Press LLC

Synonyms: methanal, methylene oxide, oxymethane; Formula: HCHO; MW 30.03; CAS[50-00-0]; constitutes about 50% of all aldehydes present in air; released in trace quantities from pressed wood products, burning wood, and synthetic polymers; and automobiles; colorless gas at ambient conditions; pungent suffocating odor; liquefies at –19.5°C; solidifies at –92°C; density 1.07 (air = 1); very soluble in water, soluble in organic solvents; readily polymerizes; flammable, toxic, and carcinogenic (Patnaik, 1992).

WATER ANALYSIS

Aqueous samples analyzed by HPLC using a postcolumn reaction detector; aldehyde separated on a reversed phase C-18 column; derivatized with 3-methyl-2-benzothiazolinone hydrazone and detected at 640 nm (Igawa et al., 1989).(The method was developed for cloud and fogwater analysis.)

pipe-by GC-FID (NIOSH Method 2541, 1989); recommended air flow 200 mL/min;sample volume 15 L

solu-tions; each standard injected into 120 mg portions coated-adsorbent; ative desorbed into toluene and analyzed by GC-FID as above; calibrationcurve constructed (plotting area/height response against concentrations) forquantitation

3.39

Alternatively, air passed through a solid sorbent tube containing lamino)ethanol on Chromosorb 102 or XAD-2; the derivative, 2-benzyloxazo-lidine desorbed with isooctane and analyzed by GC-FID (NIOSH Method 2502,1984)

decom-position and/or polymerization products from derivatizing agent; isooctanesolution may be readily analyzed by GC/MS using a DB-5 capillary column(Patnaik, 1991)

Alternatively, air drawn through a PTFE membrane followed by sodium bisulfitesolution in impingers; impinger solution treated with chromotropic acid and

absorbance measured by a spectrophotometer at 580 nm; a standard calibrationcurve prepared from formaldehyde standard solutions for quantitation (NIOSHMethod 3500, 1989); recommended air flow 500 mL/min; sample volume 50 L

extent

Air drawn through a midget bubbler containing 15 mL Girard T reagent; Girard

T derivative of formaldehyde analyzed by polarography; a calibration curveconstructed (plotting concentration formaldehyde/15 mL Girard T solution vs.diffusion current) for quantitation (NIOSH Method 3501, 1989); recommendedair flow rate 100 mL/min; sample volume 10 L

is –0.99 V

Alternatively, air drawn through Florisil or silica gel adsorbent coated with acidified2,4-dinitrophenylhydrazine (DNPH); the DNPH derivative of formaldehydedesorbed with isooctane, and solvent exchanged to methanol or acetonitrile;the solution analyzed by reverse phase HPLC (U.S EPA Method TO-11, 1988);recommended air flow rate 500 mL/min; sample volume 100 L

Alternatively, a measured volume of air drawn through an impinger containingammonium acetate and 2,4-pentanedione; formaldehyde forms a fluorescencederivative, 3,5-diacetyl-1,4-dihydrolutidine; fluorescence of the solution mea-sured by a filter fluorometer (Dong and Dasgupta, 1987)

(1 ppm formaldehyde in air = 1.23 mg/m3 at NTP)

© 1997 by CRC Press LLC

© 1997 by CRC Press LLC

ANALYSIS OF AQUEOUS SAMPLES

An aliquot of sample is purged with He; the analyte adsorbed over a trap (Tenax

or equivalent); the trap heated under He flow; the analyte desorbed from thetrap and transported onto a GC column for separation from other volatilecompounds and determination by a halogen specific detector (ECD or HECD)

or a mass spectrometer

and 66

analyzed within 14 days of collection

AIR ANALYSIS

Air drawn through coconut shell charcoal (100 mg/50 mg); analyte desorbed into

1020, 1987); flow rate 10 to 50 mL/min; sample volume 1 to 2 L

364 HANDBOOK OF ENVIRONMENTAL ANALYSIS

Air collected in a cryogenic trap under liquid argon; trap warmed; sample ferred onto a precooled GC column; temperature programmed; separated onthe column and determined by FID, halogen specific detector, or GC/MS

trans-(1 ppm freon-113 in air = 7.66 mg/m3 at NTP)

© 1997 by CRC Press LLC

© 1997 by CRC Press LLC

HYDROGEN CYANIDE

Formula: HCN; MW 27.03; CAS [74-90-8]; occurs in the root of certain plants, beet sugar residues, coke oven gas, and tobacco smoke; released during combustion of wool, polyurethane foam, and nylon; produced when metal cya- nides react with dilute mineral acids; colorless or pale liquid or a gas; odor of bitter almond; boils at 25.6°C; solidifies at –13.4°C; density of liquid 0.69 g/mL

at 20˚C and gas 0.95 (air = 1) at 31°C; soluble in water and alcohol, very weakly acidic; dangerously toxic and highly flammable (Patnaik, 1992).

ANALYSIS OF AQUEOUS SAMPLES

liber-ated and collected in NaOH solution; cyanide analyzed by colorimetric or

by ion selective electrode method (See Cyanide, Chapter 2.6)

stain due to HCN

Presence of HCN indicated by color change of 4-(2-pyridylazo) ladium in carbonate-bicarbonate buffer solution from intense red to yellow(Carducci et al., 1982)

toxicological substances; no precision and accuracy data available for ronmental samples of aqueous matrices

envi-AIR ANALYSIS

Air drawn through a solid sorbent tube containing soda lime (600 mb/200 mg);cyanide complex desorbed into deionized water; solution treated with N-chlo-rosuccinimide-succinimide oxidizing reagent; after several minutes standing

3.41

366 HANDBOOK OF ENVIRONMENTAL ANALYSIS

barbituric acid-pyridine coupling reagent added; color development measured

at 580 nm by a spectrophotometer; concentration determined from a calibrationstandard (NIOSH Method 6010, 1989); recommended flow rate 100 mL/min;sample volume 50 L

N-chloro-succinimide; stirred to dissolve; volume adjusted to 1 L; stable for 6 months

if refrigerated

slowly with stirring; adjust volume to 100 mL; stable for 2 months ifrefrigerated

(NIOSH Method 7904, 1984)

•

stoichi-ometric factor 1.04)

interference is eliminated by special treatment with EDTA

solution; HCN converted into NaCN; content of impinger transferred into a

overnight in an oven; NaCN hydrolyzed into sodium formate; contents cooledand diluted to 50 mL; formate ion analyzed by ion chromatography (Dolzine

et al., 1982)

(factor for converting formate ion to HCN 0.60, sample solution 50 mL)

ANALYSIS OF AQUEOUS AND NONAQUEOUS SAMPLES

Aqueous samples serially extracted with methylene chloride; the extract trated and analyzed by GC/MS

53, and 55

Soxhlett extracted with methylene chloride; extract concentrated and analyzed

368 HANDBOOK OF ENVIRONMENTAL ANALYSIS

extract analyzed by HPLC using an UV detector at 290 nm (NIOSH Method

5004, 1984); recommended air flow rate 2 L/min; sample volume 100 L

Partisil 10-ODS) at ambient temperature, 400 to 600 psi; mobile phase 1%acetic acid in water, 1 mL/min; calibration standard: same as above

not vapor, as its vapor pressure is too low

© 1997 by CRC Press LLC

© 1997 by CRC Press LLC

HYDROGEN SULFIDE

Formula: H2S; MW 34.08; CAS [7783-06-4]; ocurs in natural gas and sewer gas; formed when metal sulfides react with dilute mineral acids; colorless gas with rotten egg odor; liquefies at –60.2°C; solidifies at 85.5°C; slightly soluble

in water (4000 mg/L at 20°C); aqueous solution unstable, absorbs oxygen and decomposes to sulfur; highly toxic and flammable.

AIR ANALYSIS

photorateometric analyzer

stains of PbS detected by photocells (Kimbell, 1982); color ranges fromlight yellow to silvery black; extremely high signal amplification required

to measure stains far too light in color for rapid and continuous

as Vapor Gard); color changes from white to brown-black; dosage exposuremeasured from the length of stain in the indicator tube

(1 ppm H2S in air = 1.39 mg/m3 at NTP)

3.43

ANALYSIS OF AQUEOUS AND NONAQUEOUS SAMPLES

Aqueous samples extracted with methylene chloride; extract concentrated andsolvent exchanged to hexane; florisil cleanup (for removal of interferences);extract analyzed on GC-FID or GC/MS

Soils, sediments, or solid wastes extracted with methylene chloride by sonication

or Soxhlett extraction; extract concentrated; exchanged to hexane (if florisilcleanup required); analyzed by GC-FID or GC/MS

and then with acetone/methylene chloride (1:9) mixture; analyte eluted intothe latter fraction

or 3% SP-2100 on Supelcoport (100/120 mesh) or equivalent; capillary: fusedsilica capillary column, such as PTE-5, SPB-5, DB-5, Rtx-5, or equivalent

1-fluoronaphthalene

of collection and analyzed within 40 days of extraction

Synonym: marsh gas; Formula CH4; MW 16.04; CAS [74-82-8]; prime constituent of natural gas; formed from petroleum cracking, decay of animal and plant remains, and anaerobic fermentation of municipality landfill contents; occurs in marshy pools, landfill gas, and leachate from the landfill; colorless and odorless gas; lighter than air; gas density 0.717 g/L; liquefies at –161.4°C; soluble

in organic solvents, slightly soluble in water (25 mg/L); flammable gas.

ANALYSIS OF AQUEOUS SAMPLES AND SLUDGE DIGESTER GAS

Samples from wells are collected using a pump sufficiently submerged Sludge digester gas samples are collected in sealed containers, such as glass sampling bulbs with three-way stopcocks The containers are flushed with the digester gas or the gases from the aqueous samples to purge out air from the containers, prior to sample collection Analytical methodologies are similar for both the aqueous and the sludge digester gas samples Gas chromatographic method, discussed separately below under “Air Analysis,” is also applicable.

A measured volume of sample transferred into an Orsat-type gas-analysis tus; sample equilibrated to atmospheric pressure by adjusting leveling bulb;

oxidation assembly or a slow combustion pipet assembly by controlled electrical

determined to measure the fraction of methane originally present

Methane in aqueous sample determined by direct readout combustible gas detector,available commercially

above the solution (Henry’s law) Methane catalytically oxidizes on a heatedplatinum filament, that is part of a Wheatstone bridge The heat generatedincreases the electrical resistance of the filament which is measured andcompared against calibrated standards

3.45

374 HANDBOOK OF ENVIRONMENTAL ANALYSIS

interference can be reduced by adding solid NaOH to the container beforesampling

AIR ANALYSIS

Air collected in Tedlar bag; an aliquot of sample injected onto the GC column atambient temperature; determined by TCD or FID

2000 ppm Also, the sample volume for packed column injection should be

Carboxen 1004, Haye Sep Q, Carbosieve, Carbosphere, silica gel, activatedalumina, or any other equivalent material Fused silica nonpolar capillarycolumn may be used for low sample volume

Alternatively, sample may be analyzed by GC/MS (using a capillary column) undercryogenic conditions

(1 ppm methane in air = 0.66 mg/m3 at NTP)

© 1997 by CRC Press LLC

© 1997 by CRC Press LLC

374

METHYL BROMIDE

Synonym: bromomethane; Formula; (CH3Br; MW 94.95; CAS [74-83-9]; colorless gas with a chloroform-like smell at high concentrations; liquefies at 3.5°C; slightly soluble in water; miscible with organic solvents.

ANALYSIS OF AQUEOUS SAMPLES

Aqueous samples subjected to purge and trap extraction; volatile analyte adsorbed

on the sorbent trap thermally desorbed and swept with helium onto a GC columnfor separation; detected by HECD, ECD, FID or MSD; low retention time

a 5-mL sample aliquot (subject to matrix interference)

refriger-ated, and analyzed within 14 days

See Halogenated Hydrocarbons, Chapter 2.9 for GC columns and conditions andfor a detailed discussion

AIR ANALYSIS

The following methods are recommended:

Carbon molecular sieve adsorption; desorption at 350°C into a cryogenicallycooled troop; flash evaporated onto a capillary column GC/MS system; recom-mended sample volume 10 L; flow rate 100 mL/min

Collected in SUMMA passivated canister; transferred into a cryogenically cooledtrap attached to a GC column; determined by ECD or MSD

Precision and accuracy of the above methods not established.

(1 ppm methyl bromide in air = ~3.9 mg/m3 at NTP)

3.46

METHYL CHLORIDE

Synonym: chloromethane; Formula: CH3Cl; MW 50.49; CAS [74-87-3]; colorless gas with a faint sweet odor; freezes at –32.7°C; slightly soluble in water; miscible with organic solvents.

ANALYSIS OF AQUEOUS AND NONAQUEOUS SAMPLES

Aqueous samples subjected to purge and trap extraction; sample aliquot purgedunder helium flow; highly volatile methyl chloride transferred from aqueousmatrix to vapor phase; absorbed on a sorbent trap; analyte thermally desorbedand swept onto a GC column for separation; detected by HECD, ECD, FID orMSD; low retention time

Soils, solid waste, or sludges mixed with water or methanol; the aqueous extract

or a solution of methanol extract spiked into water; subjected to purge and trapconcentration and analyzed as above

as above

5-mL sample aliquot (subject to matrix interference)

and analyzed within 14 days

See under Halogenated Hydrocarbons, Chapter 2.9 for GC columns and conditionsand for a detailed discussion

AIR ANALYSIS

Collected in a SUMMA passivated canister under pressure using an additionalpump or at subatmospheric pressure by initially evacuating the canister; the airtransferred into a cryogenically cooled trap attached to a GC column; the trap

3.47