Table of Contents

Locator Record

Title: Polyaromatic Hydrocarbons (L31PAH_C )
Contact Number: 1-866-441-NCHS
Years of Content: 2003 - 2004
First Published: January, 2008
Revised: July, 2009
Access Constraints: None
Use Constraints: None
Geographic Coverage: National
Subject:Polyaromatic Hydrocarbons
Record Source: NHANES 2003 - 2004
Survey Methodology: NHANES 2003 - 2004 is a stratified multistage probability sample of the civilian non-institutionalized population of the U.S.
Medium: NHANES Web site; SAS transport files

Component Description

Urinary Polycyclic Aromatic Hydrocarbons (PAHs)

PAHs constitute a group of chemicals which are formed during the incomplete combustion of coal, oil and gas, garbage, and other organic substances. These compounds require metabolic activation prior to their interactions with cellular macromolecules. PAHs are ubiquitous; thus, exposure to them is widespread. In general, people are exposed to mixtures of PAHs, the sources of which include vehicle exhausts, asphalt roads, coal, coal tar, wild fires, agricultural burning, charbroiled foods, and hazardous waste sites. PAHs enter the body quickly and easily by all routes of exposure and are readily and predominantly metabolized to hydroxylated metabolites as well as glucuronide metabolites. These metabolites are excellent indicators of exposure to the parent PAHs. Although background level ranges of PAHs in air and water are known, the equivalent metabolite background levels in humans are not known. Because of increased epidemiologic data relating PAH exposure to cancer incidence, biomonitoring PAH metabolites in humans is very important.

Eligible Sample

Participants aged 6 years and older who met the subsample requirements.

Description of Laboratory Methodology

The specific analytes measured in this method are monohydroxy-PAH (OH-PAH). The procedure involves enzymatic hydrolysis of urine, extraction, derivatization and analysis using capillary gas chromatog-raphy combined with high resolution mass spectrometry (GC-HRMS). This method uses isotope dilution with carbon-13 labeled internal standards. Ions from each analyte and each carbon-13 labeled internal standard are monitored, and the abundances of each ion are measured. The ratios of these ions are used as criteria for evaluating the data. By evaluating these analytes in urine, a measurement of the body burden from PAH exposure is obtained.

Laboratory Quality Assurance and Monitoring

Urine specimens are processed, stored, and shipped to the Division of Environmental Health Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention for analysis.

Detailed specimen collection and processing instructions are discussed in the NHANES Laboratory/Medical Technologists Procedures Manual (LPM). Vials are stored under appropriate frozen (–20°C) conditions until they are shipped to National Center for Environmental Health for testing.

Mobile Examination Centers (MECs)

Laboratory team performance is monitored using several techniques. NCHS and contract consultants use a structured quality assurance evaluation during unscheduled visits to evaluate both the quality of the laboratory work and the quality-control procedures. Each laboratory staff person is observed for equipment operation, specimen collection and preparation; testing procedures and constructive feedback are given to each staff. Formal retraining sessions are conducted annually to ensure that required skill levels were maintained.

The NHANES QA/QC protocols meet the 1988 Clinical Laboratory Improvement Act mandates. Detailed QA/QC instructions are discussed in the NHANES LPM.

Analytical Laboratories

NHANES uses several methods to monitor the quality of the analyses performed by the laboratories. NCEH developed and distributed a quality control protocol for all the laboratories which outlined the Westgard rules used when running NHANES specimens. Summary statistics for each control pool, QC graphs, and any special considerations are submitted to NCHS. NCHS reviewed the data for trends or shifts. The laboratories are required to explain any identified areas of concern.

All QC procedures recommended by the manufacturers were followed. Reported results for all assays meet the Division of Laboratory Science’s quality control and quality assurance performance criteria for accuracy and precision (similar to specifications outlined by Westgard 1981).

Analytic Notes

Subsample weights

Measures of urinary PAHs were measured in a one third subsample of persons 6 years and over. Special sample weights are required to analyze these data properly. Specific sample weights for this subsample are included in this data file and should be used when analyzing these data.

Variance estimation

The analysis of NHANES 2003-2004 laboratory data must be conducted with the key survey design and basic demographic variables. The NHANES 2003-2004 Demographic Data File contains demographic and sample design variables. The recommended procedure for variance estimation requires use of stratum and PSU variables (SDMVSTRA and SDMVPSU, respectively) in the demographic data file.

Links to NHANES Data Files

This laboratory data file can be linked to the other NHANES 2003-2004 data files using the unique survey participant identifier SEQN.

Detection Limits

The detection limits were constant for all of the analytes in the data set. Two variables are provided for each of these analytes. The variable named URD___LC indicates whether the result was below the limit of detection. There are two values: “0” and “1”. “0” means that the result was at or above the limit of detection. “1” indicates that the result was below the limit of detection. The other variable named URX___ provides the analytic result for that analyte. In cases, where the result was below the limit of detection, the value for that variable is the detection limit divided by the square root of two.

Please refer to the Analytic Guidelines for further details on the use of sample weights and other analytic issues.

References

Codebook and Frequencies

SEQN - Respondent sequence number

Variable Name:
SEQN
SAS Label:
Respondent sequence number
English Text:
Respondent sequence number.
Target:
Both males and females 6 YEARS - 150 YEARS

WTSB2YR - Two-year MEC weights of subsample B

Variable Name:
WTSB2YR
SAS Label:
Two-year MEC weights of subsample B
English Text:
Two-year MEC weights of subsample B
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 to 435025.30254 Range of Values 2697 2697
. Missing 0 2697

URXP01 - 1-napthol (ng/L)

Variable Name:
URXP01
SAS Label:
1-napthol (ng/L)
English Text:
1-napthol (ng/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
33 to 733192.9 Range of Values 2595 2595
. Missing 102 2697

URDP01LC - 1-napthol comment code

Variable Name:
URDP01LC
SAS Label:
1-napthol comment code
English Text:
1-napthol comment code
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 2593 2593
1 Below lower detection limit 2 2595
. Missing 102 2697

URXP02 - 2-napthol (ng/L)

Variable Name:
URXP02
SAS Label:
2-napthol (ng/L)
English Text:
2-napthol(ng/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
71 to 345240.8 Range of Values 2575 2575
. Missing 122 2697

URDP02LC - 2-napthol comment code

Variable Name:
URDP02LC
SAS Label:
2-napthol comment code
English Text:
2-napthol comment code
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 2575 2575
1 Below lower detection limit 0 2575
. Missing 122 2697

URXP03 - 3-fluorene (ng/L)

Variable Name:
URXP03
SAS Label:
3-fluorene (ng/L)
English Text:
3-fluorene (ng/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
3.5 to 7006.6 Range of Values 2502 2502
. Missing 195 2697

URDP03LC - 3-fluorene comment code

Variable Name:
URDP03LC
SAS Label:
3-fluorene comment code
English Text:
3-fluorene comment code
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 2496 2496
1 Below lower detection limit 6 2502
. Missing 195 2697

URXP04 - 2-fluorene (ng/L)

Variable Name:
URXP04
SAS Label:
2-fluorene (ng/L)
English Text:
2-fluorene (ng/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
10 to 9987.7 Range of Values 2521 2521
. Missing 176 2697

URDP04LC - 2-fluorene comment code

Variable Name:
URDP04LC
SAS Label:
2-fluorene comment code
English Text:
2-fluorene comment code
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 2521 2521
1 Below lower detection limit 0 2521
. Missing 176 2697

URXP05 - 3-phenanthrene (ng/L)

Variable Name:
URXP05
SAS Label:
3-phenanthrene (ng/L)
English Text:
3-phenanthrene (ng/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
3.5 to 21153.2 Range of Values 2426 2426
. Missing 271 2697

URDP05LC - 3-phenanthrene comment code

Variable Name:
URDP05LC
SAS Label:
3-phenanthrene comment code
English Text:
3-phenanthrene comment code
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 2420 2420
1 Below lower detection limit 6 2426
. Missing 271 2697

URXP06 - 1-phenanthrene (ng/L)

Variable Name:
URXP06
SAS Label:
1-phenanthrene (ng/L)
English Text:
1-phenanthrene (ng/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
3.5 to 8826.3 Range of Values 2496 2496
. Missing 201 2697

URDP06LC - 1-phenanthrene comment code

Variable Name:
URDP06LC
SAS Label:
1-phenanthrene comment code
English Text:
1-phenanthrene comment code
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 2495 2495
1 Below lower detection limit 1 2496
. Missing 201 2697

URXP07 - 2-phenanthrene (ng/L)

Variable Name:
URXP07
SAS Label:
2-phenanthrene (ng/L)
English Text:
2-phenanthrene (ng/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
3.5 to 5877.4 Range of Values 2512 2512
. Missing 185 2697

URDP07LC - 2-phenanthrene comment code

Variable Name:
URDP07LC
SAS Label:
2-phenanthrene comment code
English Text:
2-phenanthrene comment code
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 2481 2481
1 Below lower detection limit 31 2512
. Missing 185 2697

URXP10 - 1-pyrene (ng/L)

Variable Name:
URXP10
SAS Label:
1-pyrene (ng/L)
English Text:
1-pyrene (ng/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
3.5 to 4354 Range of Values 2515 2515
. Missing 182 2697

URDP10LC - 1-pyrene comment code

Variable Name:
URDP10LC
SAS Label:
1-pyrene comment code
English Text:
1-pyrene comment code
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 2499 2499
1 Below lower detection limit 16 2515
. Missing 182 2697

URXP17 - 9-fluorene (ng/L)

Variable Name:
URXP17
SAS Label:
9-fluorene (ng/L)
English Text:
9-fluorene (ng/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
9.2 to 23952.8 Range of Values 2504 2504
. Missing 193 2697

URDP17LC - 9-fluorene comment code

Variable Name:
URDP17LC
SAS Label:
9-fluorene comment code
English Text:
9-fluorene comment code
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 2504 2504
1 Below lower detection limit 0 2504
. Missing 193 2697

URXP19 - 4-phenanthrene (ng/L)

Variable Name:
URXP19
SAS Label:
4-phenanthrene (ng/L)
English Text:
4-phenanthrene (ng/L)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
3.5 to 880.4 Range of Values 2443 2443
. Missing 254 2697

URDP19LC - 4-phenanthrene comment code

Variable Name:
URDP19LC
SAS Label:
4-phenanthrene comment code
English Text:
4-phenanthrene comment code
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 2230 2230
1 Below lower detection limit 213 2443
. Missing 254 2697

URXUCR - Creatinine, urine (mg/dL)

Variable Name:
URXUCR
SAS Label:
Creatinine, urine (mg/dL)
English Text:
Creatinine, urine (mg/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
9 to 882 Range of Values 2623 2623
. Missing 74 2697