Table of Contents

Component Description

Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) [coplanar and several mono-ortho-substituted PCBs] are similar classes of chlorinated aromatic chemicals that are produced as contaminants or byproducts. They have no known commercial or natural use. Dioxins are produced primarily during the incineration or burning of waste; the bleaching processes used in pulp and paper mills; and the chemical syntheses of trichlorophenoxyacetic acid, hexachlorophene, vinyl chloride, trichlorophenol, and pentachlorophenol. Both the synthesis and heat-related degradation of PCBs will produce PCDF by-products. PCBs are chlorinated aromatic hydrocarbon chemicals that were once synthesized for use as heat-exchanger, transformer, and hydraulic fluids, and also used as additives to paints, oils, window caulking, and floor tiles.

Production of PCBs peaked in the early 1970s and was banned in the United States after 1979. Together with the PCDDs and PCDFs, cPCBs and mPCBs are often referred to as “dioxin-like” chemicals because they act in the body through a similar mechanism.

In the environment, these dioxin-like chemicals are persistent and usually occur as a mixture of congeners (i.e., compounds that differ by the numbers and positions of chlorine atoms attached to the dibenzo-p-dioxin, dibenzofuran, or biphenyl structures). The general population is exposed to low levels of these dioxin-like chemicals primarily through ingestion of high-fat foods such as dairy products, eggs, and animal fats, and some fish and wildlife.

Eligible Sample

Examined participants aged 12 years and older from a one-third sample were eligible.

Description of Laboratory Methodology

The 17 PCDDs/PCDFs, and four cPCBs were measured in serum by gas chromatography/isotope-dilution high-resolution mass spectrometry (GC/ID-HRMS). The analytical method for PCDDs/PCDFs/cPCB is described in Patterson et al., 1990 and Turner et al., 1994. The method for PCBs is described in Sjodin et al., 2004 and Barr et al., 2003.

Refer to the Laboratory Method Files section for a detailed description of the laboratory methods used.

There were no changes to the lab method, lab equipment, or lab site for this component in the NHANES 2005-2006 cycle. However, the samples were measured in a pooled fashion for 2005-2006 rather than individual measurements.

Laboratory Quality Assurance and Monitoring

Serum samples were processed, stored and shipped to the Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA for analysis. 

Detailed instructions on specimen collection and processing are discussed in the NHANES Laboratory Procedure Manual (LPM). Vials are stored under appropriate frozen (-30oC) conditions until they were shipped to the National Center for Environmental Health for testing. 

The NHANES quality assurance and quality control (QA/QC) protocols meet the 1988 Clinical Laboratory Improvement Act mandates. Detailed QA/QC instructions are discussed in the NHANES LPM.

Mobile Examination Centers (MECs)

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

Analytical Laboratories

NHANES uses several methods to monitor the quality of the analyses performed by the contract laboratories. In the MEC, these methods include performing blind split samples collected during “dry run” sessions. In addition, contract laboratories randomly perform repeat testing on 2% of all specimens.

NCHS developed and distributed a quality control protocol for all CDC and contract laboratories, which outlined the use of Westgard rules (Westgard, et al. 1981) when running NHANES specimens. Progress reports containing any problems encountered during shipping or receipt of specimens, summary statistics for each control pool, QC graphs, instrument calibration, reagents, and any special considerations are submitted to NCHS quarterly. The reports are reviewed for trends or shifts in the data. 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 Sciences’ quality control and quality assurance performance criteria for accuracy and precision, similar to the Westgard rules (Caudill, et al. 2008).

Data Processing and Editing

The data were reviewed. Incomplete data or improbable values were sent to the performing laboratory for confirmation.

Analytic Notes

Refer to the 2005-2006 Laboratory Data Overview for general information on NHANES laboratory data.

Please refer to the NHANES Analytic Guidelines and the on-line NHANES Tutorial for details on the use of sample weights and analytic issues.

Subsample Weights

The original pooled-sample weight created for this file released in July 2013 was not correctly stratified to the U.S population total. This new file contains the corrected sample weight (WTSMSMPA). No changes or corrections were made to the lab analyte data in this new release. Any analyses of the data using the old public use data file should be repeated using the corrected sample weight on this file.

Dioxins and furans were measured in a one third subsample of persons 12 years and over, and samples were pooled in groups of 8 samples per pool within 32 demographic groups. The analysis of NHANES 2005-2006 pooled-sample data must be conducted with the basic demographic variables provided in this data file. This pooled-sample data file cannot be linked to other NHANES 2005-2006 data. Because each sample person does not have an equal probability of selection, sample weighting is needed to produce correct population estimates of means, percentiles, and other descriptive statistics.

Samples were pooled in groups of 8 samples per pool within 40 demographic groups. The analysis of NHANES 2005-2006 pooled-sample data must be conducted with the basic demographic variables provided in this data file. This pooled-sample data file cannot be linked to other NHANES 2005-2006 data. Because each sample person does not have an equal probability of selection, sample weighting is needed to produce correct population estimates of means, percentiles, and other descriptive statistics.

The pooled-sample weights required to produce estimates from these data are included in this data file.  The analysis of pooled-samples from survey data is a relatively new field of study, and there is currently no established method to produce variance estimates for these pooled results.   These data cannot be analyzed using software designed for complex surveys because design features are not available. 

Rationale and Methods Used to Create Pooled Results

The Centers for Disease Control and Prevention (CDC) provide an ongoing assessment of the US population's exposure to environmental chemicals by using Biomonitoring in conjunction with CDC's National Health and Nutrition Examination Survey (NHANES). Characterizing the distributions of concentrations of environmental compounds or their metabolites in the US population is a primary objective of CDC's Biomonitoring program. Historically, this characterization has been based on individual measurements of these compounds in body fluid or tissue from representative samples of the population. Pooling samples allows for larger sample volumes, which can result in lower limits of detection and reduces the number of measurements and costs. For the first time in NHANES 2005-2006, a weighted pooled-sample design was implemented to facilitate pooling samples before making analytical measurements (pooled results were not weighted in NHANES 2001-2002). Table 1 lists the IUPAC (International Union of Pure and Applied Chemistry (IUPAC) names, common abbreviation, and NHANES variable name for the analytes included in this data file.

Pools were prepared from serum collected from a random one-third subset of the NHANES 2005–2006 participants aged 12 years and older. Samples were pooled based on gender, race and Hispanic origin, and age. To implement the pooled-sample design, each participant sample was identified as belonging to one of 32 demographic groups based on race and Hispanic origin (non-Hispanic white: NHW, non-Hispanic black: NHB, Mexican American: MA,: OTHER, not non-Hispanic black, non-Hispanic white or Mexican-American), gender (Male, Female), and age group (12-19, 20-39, 40-59, and 60+ years of age and older). Eight (8) samples were included in each pool. The number of pools created for each of the 32 demographic groups varied depending on the total number of individual samples available in a demographic group. The one-third subset of NHANES 2005-2006 represents 2345 individual samples, but because the pooled-sample design requires that all samples be of sufficient volume and that there be the same number of samples in each pool, only 1973 samples were available to create 247 pools with 8 samples per pool.  See more details on pool sample formation and exceptions in Table 2. The variable SAMPLEID denotes the identification number for each pool and ranges from 1 through 247. Please refer to the Pooled-Sample Technical Support file (POOLTF_D) for detailed information on individual participants included in each pool.

In order to incorporate sample weighting into the pooled-sample design it was necessary to use a different volume of material from each sample contributing to a pool. The volume chosen for each sample in a pool was based on the ratio of its sampling weight to the sum of the sampling weights of all samples in the pool. To physically accomplish the pooling in the laboratory required that the ratio of the largest to the smallest sampling weight of samples in the same pool be no larger than about 4 or 5. The individual samples were sorted/stratified by sampling weight within each of the 32 demographic groups and pools were formed with sampling weights adjacent to one another in the sorted list. The number of samples in the one-third subset, the number of samples available, the number of these samples that were usable, and the number of pools formed in each demographic group are presented in Table 2. Once the pools were created, summed sampling weights were further adjusted to account for the unused samples. These adjusted summed sampling weights are represented by the variable named WTSMSMPA.

Demographic and Other Related Variables

The analysis of NHANES laboratory data must be conducted using the appropriate survey design and demographic variables. The NHANES 2005-2006 Demographics File contains demographic data, health indicators, and other related information collected during household interviews as well as the 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.

The Fasting Questionnaire File includes auxiliary information, such as fasting status, length of fast and the time of venipuncture.

This laboratory data file can be linked to the other NHANES data files using the unique survey participant identifier (i.e., SEQN).

Detection Limits 

In the dataset, the whole weight detection limit (fg/g serum) is a variable and dependent on the available sample size, however, the variation in sample size was low.  Three variables are provided for each of these analytes.  The variable name ending in “LC” (ex., LBDD01LC) indicates whether the result was below the limit of detection: the value “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 varibale ending in “LA” (ex., LBCD01LA) is the lipid adjusted detection limits in ng/g lipid, because the lipid levels are measured in individual pools/specimens.  The third variable prefixed LBC (ex., LBCD01) provides the analytic result for that analyte.  For analytes with analytic results below the lower limit of detection (ex., LBDD01LC= 1), an imputed fill value was placed in the analyte results field. This value is the lower limit of detection divided by the square root of 2 (LLOD/sqrt[2]). The lower limit of detection (LLOD in pg/g serum and ng/g lipid) for DOX: 

Table 1. NHANES Variable name, common abbreviation and International Union of Pure and Applied Chemistry (IUPAC) name for each analyte reported. Maximum limit of detection (MLOD) expressed as pg/g serum and ng/g lipid.

  Table 1. NHANES Variable name, common abbreviation and International Union of Pure and Applied Chemistry (IUPAC) name for each analyte reported. Maximum limit of detection (MLOD) expressed as pg/g serum and ng/g lipid.

 

Table 2. Number of subjects per demographic group in the NHANES 2005–2006 one-third subsample, number of individual serum samples available, number of usable samples, and number of pools formed from usable samples.

Table 2. Number of subjects per demographic group in the NHANES 2005–2006 one-third subsample, number of individual serum samples available, number of usable samples, and number of pools formed from usable samples.

1 Value of this categorical variable in the data set.
2 With only 23 usable samples, two 8 sample pools and one 7 sample pool were created.
3 With only 6 usable samples, one 6 sample pool was created.  

Methodological Considerations for analysis

The analysis of pooled-samples from survey data is a relatively new field of study, and there is currently no established method to produce variance estimates for these pooled results. These data cannot be analyzed using software designed for complex surveys because design features are not available.

There are a few pooled-sample methodological publications, which address issues related to the following topics (See References).

• Variance estimation and bias correction when pooling samples from log-normally distributed populations (Caudill, 2010a; Caudill, 2010b; Caudill et al., 2007; Li et al., 2014);
• Models that incorporate measurement error when analyzing pooled-samples from normally or log-normally distributed populations (Caudill, 2010a);
• Incorporation of sample weighting into a pooled-sample design (Caudill, 2012; Caudill, 2010a; Li et al., 2014);
• Estimation of standard errors and confidence limits for point estimates from pooled-samples (Caudill, 2012; Caudill, 2010a; Li et al., 2014; Caudill, 2015).

References

Codebook and Frequencies

SAMPLEID - Pool identification number

Variable Name:
SAMPLEID
SAS Label:
Pool identification number
English Text:
Pool identification number
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 to 247 Range of Values 247 247
. Missing 0 247

RIAGENDR - Gender

Variable Name:
RIAGENDR
SAS Label:
Gender
English Text:
Gender
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Male 114 114
2 Female 133 247
. Missing 0 247

ETHNICTY - Ethnicity - Recode

Variable Name:
ETHNICTY
SAS Label:
Ethnicity - Recode
English Text:
Ethnicity - Recode
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Non-Hispanic White 104 104
2 Non-Hispanic Black 62 166
3 Mexican American 62 228
4 Other Hispanic & Non-Hispanic Multi-Racial 19 247
. Missing 0 247

RIDAGGRP - Age at Screening Adjudicated - Recode

Variable Name:
RIDAGGRP
SAS Label:
Age at Screening Adjudicated - Recode
English Text:
Age at Screening Adjudicated - Recode
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 12-19 78 78
2 20-39 66 144
3 40-59 52 196
4 60+ 51 247
. Missing 0 247

RIANSMP - Number of samples in a pool

Variable Name:
RIANSMP
SAS Label:
Number of samples in a pool
English Text:
Number of samples in a pool
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
6 to 8 Range of Values 247 247
. Missing 0 247

WTSMSMPA - Adjust sum sampling weights in same pool

Variable Name:
WTSMSMPA
SAS Label:
Adjust sum sampling weights in same pool
English Text:
Adjusted sum sampling weights in same pool
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
59702.062036 to 3228037.3031 Range of Values 247 247
. Missing 0 247

LBCD01 - 1,2,3,7,8-pncdd (fg/g)

Variable Name:
LBCD01
SAS Label:
1,2,3,7,8-pncdd (fg/g)
English Text:
1,2,3,7,8-Pentachlorodibenzo-p-dioxin (pncdd) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1.59 to 106 Range of Values 246 246
. Missing 1 247

LBCD02 - 1,2,3,4,7,8-hxcdd (fg/g)

Variable Name:
LBCD02
SAS Label:
1,2,3,4,7,8-hxcdd (fg/g)
English Text:
1,2,3,4,7,8-Hexachlorodibenzo-p-dioxin (hxcdd)(fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.392 to 112 Range of Values 246 246
. Missing 1 247

LBCD03 - 1,2,3,6,7,8-hxcdd (fg/g)

Variable Name:
LBCD03
SAS Label:
1,2,3,6,7,8-hxcdd (fg/g)
English Text:
1,2,3,6,7,8-Hexachlorodibenzo-p-dioxin (hxcdd)(fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.312 to 627 Range of Values 246 246
. Missing 1 247

LBCD04 - 1,2,3,7,8,9-hxcdd (fg/g)

Variable Name:
LBCD04
SAS Label:
1,2,3,7,8,9-hxcdd (fg/g)
English Text:
1,2,3,7,8,9-Hexachlorodibenzo-p-dioxin (hxcdd) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.206 to 79.3 Range of Values 246 246
. Missing 1 247

LBCD05 - 1,2,3,4,6,7,8-hpcdd (fg/g)

Variable Name:
LBCD05
SAS Label:
1,2,3,4,6,7,8-hpcdd (fg/g)
English Text:
1,2,3,4,6,7,8-Heptachlororodibenzo-p-dioxin (hpcdd) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
42.5 to 759 Range of Values 246 246
. Missing 1 247

LBCD07 - 1,2,3,4,6,7,8,9-ocdd (fg/g)

Variable Name:
LBCD07
SAS Label:
1,2,3,4,6,7,8,9-ocdd (fg/g)
English Text:
1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin (ocdd) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
319 to 9590 Range of Values 246 246
. Missing 1 247

LBCF01 - 2,3,7,8,-Tetrachlorofuran (tcdf) (fg/g)

Variable Name:
LBCF01
SAS Label:
2,3,7,8,-Tetrachlorofuran (tcdf) (fg/g)
English Text:
2,3,7,8-Tetrachlorodibenzofuran (tcdf) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.648 to 12.1 Range of Values 246 246
. Missing 1 247

LBCF02 - 1,2,3,7,8-Pentachlorofuran(pncdf)(fg/g)

Variable Name:
LBCF02
SAS Label:
1,2,3,7,8-Pentachlorofuran(pncdf)(fg/g)
English Text:
1,2,3,7,8-Pentachlorodibenzofuran (pncdf) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1.17 to 11.7 Range of Values 246 246
. Missing 1 247

LBCF03 - 2,3,4,7,8-Pentachlorofuran(pncdf)(fg/g)

Variable Name:
LBCF03
SAS Label:
2,3,4,7,8-Pentachlorofuran(pncdf)(fg/g)
English Text:
2,3,4,7,8-Pentachlorodibenzofuran (pncdf) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1.31 to 135 Range of Values 246 246
. Missing 1 247

LBCF04 - 1,2,3,4,7,8-Hexachlorofuran(hcxdf)(fg/g)

Variable Name:
LBCF04
SAS Label:
1,2,3,4,7,8-Hexachlorofuran(hcxdf)(fg/g)
English Text:
1,2,3,4,7,8-Hexachlorodibenzofuran (hcxdf) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.765 to 83.9 Range of Values 246 246
. Missing 1 247

LBCF05 - 1,2,3,6,7,8-Hexachlorofuran(hxcdf)(fg/g)

Variable Name:
LBCF05
SAS Label:
1,2,3,6,7,8-Hexachlorofuran(hxcdf)(fg/g)
English Text:
1,2,3,6,7,8-Hexachlorodibenzofuran (hxcdf) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.269 to 69.3 Range of Values 246 246
. Missing 1 247

LBCF06 - 1,2,3,7,8,9-Hexachlorodifuran (fg/g)

Variable Name:
LBCF06
SAS Label:
1,2,3,7,8,9-Hexachlorodifuran (fg/g)
English Text:
1,2,3,7,8,9-Hexachlorodibenzofuran (hxcdf) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.506 to 1.93 Range of Values 246 246
. Missing 1 247

LBCF07 - 2,3,4,6,7,8,-Hexchlorofuran(hxcdf)(fg/g)

Variable Name:
LBCF07
SAS Label:
2,3,4,6,7,8,-Hexchlorofuran(hxcdf)(fg/g)
English Text:
2,3,4,6,7,8-Hexchlorodibenzofuran (hxcdf) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.29 to 27.6 Range of Values 246 246
. Missing 1 247

LBCF08 - 1,2,3,4,6,7,8-Heptachlorodifuran (fg/g)

Variable Name:
LBCF08
SAS Label:
1,2,3,4,6,7,8-Heptachlorodifuran (fg/g)
English Text:
1,2,3,4,6,7,8-Heptachlorodibenzofuran (hpcdf) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
19.5 to 137 Range of Values 246 246
. Missing 1 247

LBCF09 - 1,2,3,4,7,8,9-Heptachlorodifuran (fg/g)

Variable Name:
LBCF09
SAS Label:
1,2,3,4,7,8,9-Heptachlorodifuran (fg/g)
English Text:
1,2,3,4,7,8,9-Heptachlorodibenzofuran (hpcdf) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.486 to 3.68 Range of Values 246 246
. Missing 1 247

LBCF10 - 1,2,3,4,6,7,8,9-Octachlorodifuran (fg/g)

Variable Name:
LBCF10
SAS Label:
1,2,3,4,6,7,8,9-Octachlorodifuran (fg/g)
English Text:
1,2,3,4,6,7,8,9-ocdf lipid adjusted(pg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
3.51 to 108 Range of Values 246 246
. Missing 1 247

LBCHXC - 3,3',4,4',5,5'-hexachlorobiphenyl(fg/g)

Variable Name:
LBCHXC
SAS Label:
3,3',4,4',5,5'-hexachlorobiphenyl(fg/g)
English Text:
3,3',4,4',5,5'-hexachlorobiphenyl (hxcb) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
3.52 to 463 Range of Values 246 246
. Missing 1 247

LBCPCB - 3,3',4,4',5-Pentachlorobiphenyl (fg/g)

Variable Name:
LBCPCB
SAS Label:
3,3',4,4',5-Pentachlorobiphenyl (fg/g)
English Text:
3,3',4,4',5-Pentachlorobiphenyl (pncb) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
17.7 to 1270 Range of Values 246 246
. Missing 1 247

LBCTC2 - 3,4,4',5-Tetrachlorobiphenyl(tcb)(fg/g)

Variable Name:
LBCTC2
SAS Label:
3,4,4',5-Tetrachlorobiphenyl(tcb)(fg/g)
English Text:
3,4,4',5-Tetrachlorobiphenyl (tcb) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
4.79 to 79.3 Range of Values 246 246
. Missing 1 247

LBCTCD - 2,3,7,8-Tetrachloro-p-dioxn(tcdd)(fg/g)

Variable Name:
LBCTCD
SAS Label:
2,3,7,8-Tetrachloro-p-dioxn(tcdd)(fg/g)
English Text:
2,3,7,8-Tetrachlorodienzo-p-dioxin (tcdd) (fg/g)
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1.09 to 75.9 Range of Values 246 246
. Missing 1 247

LBCD01LA - 1,2,3,7,8-pncdd lipid adjusted (pg/g)

Variable Name:
LBCD01LA
SAS Label:
1,2,3,7,8-pncdd lipid adjusted (pg/g)
English Text:
1,2,3,7,8-Pentachlorodibenzo-p-dioxin (pncdd) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.187 to 17.3 Range of Values 246 246
. Missing 1 247

LBCD02LA - 1,2,3,4,7,8-hxcdd lipid adjusted (pg/g)

Variable Name:
LBCD02LA
SAS Label:
1,2,3,4,7,8-hxcdd lipid adjusted (pg/g)
English Text:
1,2,3,4,7,8-Hexachlorodibenzo-p-dioxin (hxcdd) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.0462 to 18.3 Range of Values 246 246
. Missing 1 247

LBCD03LA - 1,2,3,6,7,8-hxcdd lipid adjusted (pg/g)

Variable Name:
LBCD03LA
SAS Label:
1,2,3,6,7,8-hxcdd lipid adjusted (pg/g)
English Text:
1,2,3,6,7,8-Hexachlorodibenzo-p-dioxin (hxcdd) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.0509 to 90 Range of Values 246 246
. Missing 1 247

LBCD04LA - 1,2,3,7,8,9-hxcdd lipid adjusted (pg/g)

Variable Name:
LBCD04LA
SAS Label:
1,2,3,7,8,9-hxcdd lipid adjusted (pg/g)
English Text:
1,2,3,7,8,9-Hexachlorodibenzo-p-dioxin (hxcdd) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.0243 to 11.7 Range of Values 246 246
. Missing 1 247

LBCD05LA - 1,2,3,4,6,7,8-hpcdd lipid adjusted(pg/g)

Variable Name:
LBCD05LA
SAS Label:
1,2,3,4,6,7,8-hpcdd lipid adjusted(pg/g)
English Text:
1,2,3,4,6,7,8-Heptachlororodibenzo-p-dioxin (hpcdd) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
8.37 to 112 Range of Values 246 246
. Missing 1 247

LBCD07LA - 1,2,3,4,6,7,8,9-ocdd lipid adjusted(pg/g

Variable Name:
LBCD07LA
SAS Label:
1,2,3,4,6,7,8,9-ocdd lipid adjusted(pg/g
English Text:
1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin (ocdd) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
62.8 to 1350 Range of Values 246 246
. Missing 1 247

LBCF01LA - 2,3,7,8-tcdf lipid adjusted (pg/g)

Variable Name:
LBCF01LA
SAS Label:
2,3,7,8-tcdf lipid adjusted (pg/g)
English Text:
2,3,7,8-Tetrachlorodibenzofuran (tcdf) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.0733 to 1.43 Range of Values 246 246
. Missing 1 247

LBCF02LA - 1,2,3,7,8-pncdf lipid adjusted (pg/g)

Variable Name:
LBCF02LA
SAS Label:
1,2,3,7,8-pncdf lipid adjusted (pg/g)
English Text:
1,2,3,7,8-Pentachlorodibenzofuran (pncdf) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.133 to 1.31 Range of Values 246 246
. Missing 1 247

LBCF03LA - 2,3,4,7,8-pncdf lipid adjusted (pg/g)

Variable Name:
LBCF03LA
SAS Label:
2,3,4,7,8-pncdf lipid adjusted (pg/g)
English Text:
2,3,4,7,8-Pentachlorodibenzofuran (pncdf) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.226 to 20 Range of Values 246 246
. Missing 1 247

LBCF04LA - 1,2,3,4,7,8-hcxdf lipid adjusted (pg/g)

Variable Name:
LBCF04LA
SAS Label:
1,2,3,4,7,8-hcxdf lipid adjusted (pg/g)
English Text:
1,2,3,4,7,8-Hexachlorodibenzofuran (hcxdf) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.0899 to 12.4 Range of Values 246 246
. Missing 1 247

LBCF05LA - 1,2,3,6,7,8-hxcdf lipid adjusted (pg/g)

Variable Name:
LBCF05LA
SAS Label:
1,2,3,6,7,8-hxcdf lipid adjusted (pg/g)
English Text:
1,2,3,6,7,8-Hexachlorodibenzofuran (hxcdf) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.0316 to 9.58 Range of Values 246 246
. Missing 1 247

LBCF06LA - 1,2,3,7,8,9-hxcdf lipid adjusted (pg/g)

Variable Name:
LBCF06LA
SAS Label:
1,2,3,7,8,9-hxcdf lipid adjusted (pg/g)
English Text:
1,2,3,7,8,9-Hexachlorodibenzofuran (hxcdf) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.0566 to 0.25 Range of Values 246 246
. Missing 1 247

LBCF07LA - 2,3,4,6,7,8-hxcdf lipid adjusted (pg/g)

Variable Name:
LBCF07LA
SAS Label:
2,3,4,6,7,8-hxcdf lipid adjusted (pg/g)
English Text:
2,3,4,6,7,8-Hexchlorodibenzofuran (hxcdf) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.034 to 4.51 Range of Values 246 246
. Missing 1 247

LBCF08LA - 1,2,3,4,6,7,8-hpcdf lipid adjusted(pg/g)

Variable Name:
LBCF08LA
SAS Label:
1,2,3,4,6,7,8-hpcdf lipid adjusted(pg/g)
English Text:
1,2,3,4,6,7,8-Heptachlorodibenzofuran (hpcdf) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
2.71 to 27.7 Range of Values 246 246
. Missing 1 247

LBCF09LA - 1,2,3,4,7,8,9-hpcdf lipid adjusted(pg/g)

Variable Name:
LBCF09LA
SAS Label:
1,2,3,4,7,8,9-hpcdf lipid adjusted(pg/g)
English Text:
1,2,3,4,7,8,9-Heptachlorodibenzofuran (Hpcdf) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.0543 to 0.602 Range of Values 246 246
. Missing 1 247

LBCF10LA - 1,2,3,4,6,7,8,9-ocdf lipid adjusted(pg/g

Variable Name:
LBCF10LA
SAS Label:
1,2,3,4,6,7,8,9-ocdf lipid adjusted(pg/g
English Text:
1,2,3,4,6,7,8,9-Octachlorodibenzofuran (ocdf) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.385 to 16.1 Range of Values 246 246
. Missing 1 247

LBCHXCLA - 3,3',4,4',5,5'-hxcb Lipid adjusted(pg/g)

Variable Name:
LBCHXCLA
SAS Label:
3,3',4,4',5,5'-hxcb Lipid adjusted(pg/g)
English Text:
3,3',4,4',5,5'-hexachlorobiphenyl (hxcb) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.564 to 68.5 Range of Values 246 246
. Missing 1 247

LBCPCBLA - 3,3',4,4',5-pncb lipid adjusted (pg/g)

Variable Name:
LBCPCBLA
SAS Label:
3,3',4,4',5-pncb lipid adjusted (pg/g)
English Text:
3,3',4,4',5-Pentachlorobiphenyl (pncb) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
3.72 to 188 Range of Values 246 246
. Missing 1 247

LBCTC2LA - 3,4,4',5-tcb lipid adjusted (pg/g)

Variable Name:
LBCTC2LA
SAS Label:
3,4,4',5-tcb lipid adjusted (pg/g)
English Text:
3,4,4',5-Tetrachlorobiphenyl (tcb) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.602 to 11.6 Range of Values 246 246
. Missing 1 247

LBCTCDLA - 2,3,7,8-tcdd lipid adjusted (pg/g)

Variable Name:
LBCTCDLA
SAS Label:
2,3,7,8-tcdd lipid adjusted (pg/g)
English Text:
2,3,7,8-Tetrachlorodienzo-p-dioxin (tcdd) Lipid Adjusted
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.121 to 11.2 Range of Values 246 246
. Missing 1 247

LBDD01LC - 1,2,3,7,8-pncdd comment code

Variable Name:
LBDD01LC
SAS Label:
1,2,3,7,8-pncdd comment code
English Text:
1,2,3,7,8-Pentachlorodibenzo-p-dioxin (pncdd) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 221 221
1 Below lower detection limit 25 246
. Missing 1 247

LBDD02LC - 1,2,3,4,7,8-hxcdd comment code

Variable Name:
LBDD02LC
SAS Label:
1,2,3,4,7,8-hxcdd comment code
English Text:
1,2,3,4,7,8-Hexachlorodibenzo-p-dioxin (hxcdd) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 159 159
1 Below lower detection limit 87 246
. Missing 1 247

LBDD03LC - 1,2,3,6,7,8-hxcdd comment code

Variable Name:
LBDD03LC
SAS Label:
1,2,3,6,7,8-hxcdd comment code
English Text:
1,2,3,6,7,8-Hexachlorodibenzo-p-dioxin (hxcdd) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 234 234
1 Below lower detection limit 12 246
. Missing 1 247

LBDD04LC - 1,2,3,7,8,9-hxcdd comment code

Variable Name:
LBDD04LC
SAS Label:
1,2,3,7,8,9-hxcdd comment code
English Text:
1,2,3,7,8,9-Hexachlorodibenzo-p-dioxin (hxcdd) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 199 199
1 Below lower detection limit 47 246
. Missing 1 247

LBDD05LC - 1,2,3,4,6,7,8-hpcdd comment code

Variable Name:
LBDD05LC
SAS Label:
1,2,3,4,6,7,8-hpcdd comment code
English Text:
1,2,3,4,6,7,8-Heptachlororodibenzo-p-dioxin (hpcdd) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 246 246
1 Below lower detection limit 0 246
. Missing 1 247

LBDD07LC - 1,2,3,4,6,7,8,9-ocdd comment code

Variable Name:
LBDD07LC
SAS Label:
1,2,3,4,6,7,8,9-ocdd comment code
English Text:
1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin (ocdd) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 246 246
1 Below lower detection limit 0 246
. Missing 1 247

LBDF01LC - 2,3,7,8-tcdf comment code

Variable Name:
LBDF01LC
SAS Label:
2,3,7,8-tcdf comment code
English Text:
2,3,7,8-Tetrachlorodibenzofuran (tcdf) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 19 19
1 Below lower detection limit 227 246
. Missing 1 247

LBDF02LC - 1,2,3,7,8-pncdf comment code

Variable Name:
LBDF02LC
SAS Label:
1,2,3,7,8-pncdf comment code
English Text:
1,2,3,7,8-Pentachlorodibenzofuran (pncdf) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 41 41
1 Below lower detection limit 205 246
. Missing 1 247

LBDF03LC - 2,3,4,7,8-pncdf comment code

Variable Name:
LBDF03LC
SAS Label:
2,3,4,7,8-pncdf comment code
English Text:
2,3,4,7,8-Pentachlorodibenzofuran (pncdf) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 238 238
1 Below lower detection limit 8 246
. Missing 1 247

LBDF04LC - 1,2,3,4,7,8-hcxdf comment code

Variable Name:
LBDF04LC
SAS Label:
1,2,3,4,7,8-hcxdf comment code
English Text:
1,2,3,4,7,8-Hexachlorodibenzofuran (hcxdf) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 242 242
1 Below lower detection limit 4 246
. Missing 1 247

LBDF05LC - 1,2,3,6,7,8-hxcdf comment code

Variable Name:
LBDF05LC
SAS Label:
1,2,3,6,7,8-hxcdf comment code
English Text:
1,2,3,6,7,8-Hexachlorodibenzofuran (hxcdf) specimen code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 240 240
1 Below lower detection limit 6 246
. Missing 1 247

LBDF06LC - 1,2,3,7,8,9-hxcdf comment code

Variable Name:
LBDF06LC
SAS Label:
1,2,3,7,8,9-hxcdf comment code
English Text:
1,2,3,7,8,9-Hexachlorodibenzofuran (hxcdf) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 1 1
1 Below lower detection limit 245 246
. Missing 1 247

LBDF07LC - 2,3,4,6,7,8-hxcdf comment code

Variable Name:
LBDF07LC
SAS Label:
2,3,4,6,7,8-hxcdf comment code
English Text:
2,3,4,6,7,8-Hexchlorodibenzofuran (hxcdf) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 191 191
1 Below lower detection limit 55 246
. Missing 1 247

LBDF08LC - 1,2,3,4,6,7,8-hpcdf comment code

Variable Name:
LBDF08LC
SAS Label:
1,2,3,4,6,7,8-hpcdf comment code
English Text:
1,2,3,4,6,7,8-Heptachlorodibenzofuran (hpcdf) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 246 246
1 Below lower detection limit 0 246
. Missing 1 247

LBDF09LC - 1,2,3,4,7,8,9-hpcdf comment code

Variable Name:
LBDF09LC
SAS Label:
1,2,3,4,7,8,9-hpcdf comment code
English Text:
1,2,3,4,7,8,9-Heptachlorodibenzofuran (hpcdf) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 3 3
1 Below lower detection limit 243 246
. Missing 1 247

LBDF10LC - 1,2,3,4,6,7,8,9-ocdf comment code

Variable Name:
LBDF10LC
SAS Label:
1,2,3,4,6,7,8,9-ocdf comment code
English Text:
1,2,3,4,6,7,8,9-Octachlorodibenzofuran (ocdf) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 153 153
1 Below lower detection limit 93 246
. Missing 1 247

LBDHXCLC - 3,3',4,4',5,5'-hxcb comment code

Variable Name:
LBDHXCLC
SAS Label:
3,3',4,4',5,5'-hxcb comment code
English Text:
3,3',4,4',5,5'-hexachlorobiphenyl (hxcb) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 245 245
1 Below lower detection limit 1 246
. Missing 1 247

LBDPCBLC - 3,3',4,4',5-pncb comment code

Variable Name:
LBDPCBLC
SAS Label:
3,3',4,4',5-pncb comment code
English Text:
3,3',4,4',5-Pentachlorobiphenyl (pncb) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 246 246
1 Below lower detection limit 0 246
. Missing 1 247

LBDTC2LC - 3,4,4',5-tcb comment code

Variable Name:
LBDTC2LC
SAS Label:
3,4,4',5-tcb comment code
English Text:
3,4,4',5-Tetrachlorobiphenyl (tcb) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 207 207
1 Below lower detection limit 39 246
. Missing 1 247

LBDTCDLC - 2,3,7,8-tcdd comment code

Variable Name:
LBDTCDLC
SAS Label:
2,3,7,8-tcdd comment code
English Text:
2,3,7,8-Tetrachlorodienzo-p-dioxin (tcdd) comment code
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 130 130
1 Below lower detection limit 116 246
. Missing 1 247