California Code of Regulations › Title 22 - Social Security › Division 4.5 - Environmental Health Standards for the Management of Hazardous Waste › Chapter 11 - Identification and Listing of Hazardous Waste › Appendix XI - Organic Lead Test Method

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
1.0 Scope and Application.
1.1 This method is used to determine the sum of organic lead
				  compounds ("organolead") in liquids, solids or sludges. The method detection
				  limit for a 50 g sample is 0.5 µg/g (as lead); the method detection limit
				  for 200 ml water samples is 0.1 mg/l (as lead).
2.0 Summary of Method.
2.1 Organolead is separated from the sample matrix by
				  extraction with xylene. The organolead in the extract is reacted with Aliquat
				  336 and iodine and the solution is made up to volume with MIBK. Lead contained
				  in this mixture is determined by flame atomic absorption spectrometry (FAAS).
				  If the original sample is completely soluble in xylene, the extraction step is
				  omitted.
3.0 Safety.
3.1 Some organic lead compounds are volatile and toxic.
				  Therefore, samples must be processed in a well-ventilated hood. Antiknock lead
				  compounds are particularly poisonous and must not be inhaled or ingested or
				  come into contact with the skin. Antiknock lead compounds should never be
				  exposed to elevated temperatures (above 50°C) or to acids and oxidizing
				  agents. Whenever organic lead compounds are handled outside of a
				  well-ventilated hood, protective respiratory equipment, protective clothing and
				  rubber gloves must be worn. The material safety data sheets (MSDS) for
				  organolead standards must be read.
3.2 The solvents used in this method are flammable. Proper
				  precautions must be taken to prevent contact with sparks or open flames (other
				  than the AAS flame).
4.0 Interferences.
4.1 To reduce loss of organic lead compounds which are very
				  volatile and sensitive to oxygen, samples must not be exposed to elevated
				  temperatures or to air for extended periods of time. Such losses shall be
				  minimized by adhering to the sample collection, preservation and handling
				  procedures in subdivisions
				  7.2 -
				  7.4 and
				  8.1.1 of this appendix.
4.2 If the samples are moist, there may be poor wettability
				  with xylene.
5.0 Apparatus and Materials.
5.1 flame atomic absorption spectrometer (FAA spectrometer)
				  with background corrector and recorder or integrator;
5.2 lead hollow cathode lamp or electrodeless discharge
				  lamp;
5.3 nebulizer with impact bead; the standard rubber gasket in
				  the nebulizer must be replaced with a cork gasket because the organic solvents
				  used in this method attack rubber;
5.4 air, acetylene and appropriate AAS burner head;
5.5 erlenmeyer flasks, 250 ml and 100 ml, with ground glass
				  stoppers;
5.6 mechanical shaker;
5.7 glass filter funnel and filter paper (Whatman #40, #42 or
				  equivalent);
5.8 separatory funnels, 250 ml capacity;
5.9 volumetric flasks, 250 ml, 100 ml, and 50 ml.
6.0 Reagents.
All solvents and reagents must be at least analytical reagent
				  grade, if available.
6.1 xylene (use p-xylene if available);
6.2 methyl isobutyl ketone (MIBK,
				  4-methyl-2-pentanone);
6.3 iodine solution: dissolve 3.0 g of elemental iodine in
				  toluene and make up to 100 ml with the same solvent. Store in a brown bottle in
				  a refrigerator;
6.4 Aliquat 336 (Tri-capryl methyl ammonium chloride),
				  available from Aldrich, Milwaukee, WI, or from McKesson Co., Minneapolis, MN.
				  Aliquat is a registered trademark of Henkel Corporation. Prepare two solutions,
				  one containing 10 percent weight to volume ratio (w/v) and one containing 1
				  percent (w/v) in MIBK. Store in a refrigerator;
6.5 anhydrous sodium sulfate, granular;
6.6 lead chloride, crystals. Dry at 105°C for 3 hours
				  before use.
6.6.1 Prepare a stock solution containing 1000 mg/l of lead
				  (Pb) by dissolving 0.3356 g of lead chloride in 10 percent Aliquat 336 in MIBK
				  and dilute to 250 ml. Store in a brown bottle in a refrigerator.
6.6.2 Prepare an intermediate Pb standard by pipetting 10 ml
				  of the stock standard into a volumetric flask and diluting to 100 ml with a 40
				  percent volume to volume ratio (v/v) solution of xylene in MIBK. Store in a
				  brown bottle in a refrigerator;
6.7 sodium chloride (NaCl).
7.0 Sample Collection, Preservation, and Handling.
7.1 For safety precautions, see subdivision
				  3.0 of this appendix.
7.2 Liquid samples must be collected in amber glass bottles
				  (preferably 500 ml size) with Teflon-lined caps without leaving any headspace.
				  During sampling, contact of the sample with air must be minimized.
7.3 Solid samples must be collected in glass jars (preferably
				  250 ml size) with airtight, Teflon-lined lids. The jars must be filled to
				  capacity.
7.4 All samples must be transported and stored at
				  refrigerator temperature (approximately 5°C.).
8.0 Procedure.The order of addition of the reagents must be
				  followed explicitly. Aliquat 336 must not be added before the addition of
				  iodine because it retards the formation of the alkyl lead iodide-Aliquat 336
				  complex, giving erroneous results.
8.1 Extraction of Solid and Sludge Samples.
8.1.1 Weigh out (to the nearest 0.1 g) about 50 g of
				  homogenized sample into an Erlenmeyer flask, add 100 ml of xylene, stopper the
				  flask and shake on a mechanical shaker for 30 minutes (min). The extraction
				  efficiency may vary depending on the moisture content of the sample. Stirring
				  of the sample with a mechanical or magnetic stirrer must not be substituted for
				  shaking since it can result in loss of organolead due to oxidation by air
				  oxygen. For the same reason, extraction times of more than 30 min must be
				  avoided.
8.1.2 After extraction, filter the xylene phase through
				  filter paper holding about 10 g of anhydrous sodium sulfate.
8.1.3 Pipet 20 ml of MIBK and 20 ml of the filtered extract
				  into a 50 ml volumetric flask and mix.
8.1.4 To the same flask, add 0.1 ml of iodine solution and
				  mix again. Let react for approximately 1 min.
8.1.5 To the same flask, add 5 ml of 1 percent Aliquat 336 in
				  MIBK, dilute to volume with MIBK and mix.
8.2 Extraction of Liquid Samples.
8.2.1 Place 200 ml of the sample and 50 ml of xylene into a
				  separatory funnel, close the funnel and shake for 1 - 2 min. Allow 5 - 10 min
				  for phase separation. If less than 200 ml of sample is available, the
				  miscibility with xylene may be tested with a smaller aliquot.
8.2.2 If a single liquid phase is obtained (i.e., if the
				  sample is completely soluble in xylene), discard the sample/xylene mixture and
				  pipet 20 ml of neat sample into a 50 ml volumetric flask, add 20 ml of MIBK,
				  mix, and continue as described in subdivision
				  8.1.4 above.
8.2.3 If an emulsion is obtained which requires more time for
				  phase separation, add about 5 g of NaCl to the separatory funnel, shake
				  briefly, and let the mixture settle for 20 min.
8.2.4 After separation of the xylene phase from the sample
				  solvent phase (e.g., water), drain off the lower phase into a second separatory
				  funnel and collect the xylene extract in a 100 ml flask with ground glass
				  stopper.
8.2.5 Add 25 ml of xylene to the sample solvent phase, shake
				  for 1-2 min and allow 5 - 10 min for phase separation.
8.2.6 Repeat subdivision
				  8.2.4, adding the xylene phase to
				  the first extract. Then repeat sudivisions 8.2.5 and 8.2.4 with another 25 ml
				  of xylene.
8.2.7 Filter the combined extract through filter paper
				  holding about 10 g of anhydrous sodium sulfate.
8.2.8 Pipet 20 ml of MIBK and 20 ml of the filtered extract
				  into a 50 ml volumetric flask and mix. Continue as described in subdivision
				  8.1.4 above.
8.3 Standard and Blank Preparation.
Prepare a blank and a minimum of three appropriate working
				  standards from the intermediate organolead standard containing 100 mg/l as
				  Pb.
8.3.1 Place 40 ml of xylene into a 100 ml volumetric flask
				  and add the correct amount of the 100 mg/l standard to prepare the desired
				  concentration.
8.3.2 Immediately add 0.2 ml of iodine solution and mix
				  well.
8.3.3 Add 10 ml of 1 percent Aliquat 336 solution, dilute to
				  volume with MIBK and mix well.
8.3.4 The blank is prepared in the same way as the
				  calibration standards (subdivisions
				  8.3.1 -
				  8.3.3 of this appendix), except
				  that no organolead intermediate standard is added.
8.4 Flame Atomic Absorption Measurements.
Since certain organolead compounds are very volatile, their
				  vapors may remain in the nebulizer or drain tube for considerable periods of
				  time and affect subsequent readings. Therefore, sufficient time must be allowed
				  between readings for all vapors to clear the system. Analyzing a blank between
				  samples can check on the system.
8.4.1 The FAA spectrometer is set up according to the
				  manufacturer's instructions. The nebulizer is equipped with the impact bead and
				  a cork gasket is installed. Ensure that the drain tube to the waste container
				  drains properly. Tygon tubing is affected by the organic solvents used in this
				  method and drainage properties will be different from those observed with
				  aqueous samples. If desired, a waste container dedicated to receive organolead
				  waste may be connected.
8.4.2 While aspirating water into the flame, adjust the
				  acetylene flow to 8.5 l/min and the air flow to 25 l/min.
8.4.3 Aspirate MIBK containing 40 percent xylene into the
				  flame, reduce the acetylene flow to approximately 4.8 l/min and fine adjust to
				  produce an even flame with no yellow luminescence.
8.4.4 Measure the absorbance of the method blank, working
				  standards, and samples.
8.4.5 If sample readings fall outside the calibrated range,
				  the solutions to be aspirated into the nebulizer must be diluted with a 40
				  percent (v/v) solution of xylene in MIBK and analyzed again.
9.0 Calculations.
Depending on the type of sample analyzed and the method of
				  sample preparation, one of the following three formulas is used to calculate
				  the concentration of organolead in the sample:
9.1 solid and sludge samples:
Conc (µg/g) = FAA-Result (mg/l) x (100ml/W (g)) x
				  (50ml/20ml) x F
where W (g) is the sample mass in grams (usually 50 g) and F
				  is the dilution factor;
9.2 liquid samples not soluble in xylene:
Conc (mg/l) = FAA-Result (mg/l) x (100ml/V (ml)) x
				  (50ml/20ml) x F
where V (ml) is the sample volume in ml (usually 200 ml) and
				  F is the dilution factor;
9.3 xylene-soluble liquid samples:
Conc (mg/l) = FAA-Result (mg/l) x (100ml/V (ml)) x
				  (50ml/20ml) x F
where V (ml) is the sample volume in ml (usually 20 ml) and F
				  is the dilution factor.
10.0 Quality Control.
10.1 Analyze a method blank along with each batch of ten
				  samples (or less). If the blank indicates a significant contamination (more
				  than twice the method detection limit), repeat all procedures with samples and
				  blank.
10.2 Analyze a duplicate sample with each batch of ten
				  samples or less.
10.3 Analyze a spiked sample with each batch of ten samples
				  or less. The level of spiking must be about twenty times the method detection
				  limit. If the sample contains measurable organic lead, the spike level must be
				  at least four times the measured level.
10.4 Leaded gasoline with known concentration of organolead
				  must be used as spiking solution for all sample types.
11.0 Method Performance.
11.1 The analysis of four replicates of water samples spiked
				  with leaded gasoline gave a mean result of 3.23 mg/l, a standard deviation of
				  0.032 mg/l, and a relative standard deviation (RSD) of 0.99%. The mean recovery
				  was 3.23 mg/l for a recovery of 67.7%.
11.2 The instrument detection limit (IDL) was determined by
				  the analysis of eleven replicates, blanks and standards. The IDL was based on
				  three times the standard deviation which was 0.09 mg/l.
11.3 The analysis of six replicates of soil samples spiked
				  with gasoline gave a mean result of 3.16 mg/kg, a standard deviation of 0.025
				  mg/kg, and a RSD of 0.80%. The mean recovery was 3.16 mg/kg for a 66.2%
				  recovery.
1. New section
				  filed 5-24-91; effective 7-1-91 (Register 91, No.
				  22).
Note: Authority cited: Sections
					 208
					 and
					 25141,
					 Health and Safety Code. Reference: Section
					 25141,
					 Health and Safety Code.