Table of Contents

Locator Record

Title: Perfluorinated Chemicals (Surplus Sera) (SSPFC_A )
Contact Number: 1-866-441-NCHS
Years of Content: 1999 - 2000
First Published: October, 2006
Revised: September, 2012
Access Constraints: None
Use Constraints: None
Geographic Coverage: National
Subject:Perfluorinated Chemicals (Surplus Sera)
Record Source: NHANES 1999 - 2000
Survey Methodology: NHANES 1999 - 2000 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

The primary objective of this study was to characterize serum concentrations of selected perfluorinated chemicals ( PFCs), including perfluoroctanoate (PFOA) and perfluorooctanesulfonate (PFOS), in a representative random 1/3 subset of the non-occupationally exposed US population from NHANES 1999-2000, so that we could obtain national population levels for these compounds over this two-year period.

Eligible Sample

Participants aged 12 years and older who do not meet any of the exclusion criteria were eligible.

Description of Laboratory Methodology

The measurements of PFCs were performed at the Division of Laboratory Sciences (DLS), National Center for Environmental Health (NCEH), Centers for Disease Control and Prevention (CDC). Through a multiple reaction monitoring experiment, the following analytes were measured: perfluorooctane sulfonamide (PFOSA), 2-(N-ethyl-perfluorooctane sulfonamido) acetic acid (Et-PFOSA-AcOH), 2-(N-methyl-perfluorooctane sulfonamido) acetic acid (Me-PFOSA-AcOH), perfluorohexane sulfonic acid (PFHxS), PFOS, PFOA, perfluorohexanoic acid (PFHxA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDeA), perfluoroundecanoic acid (PFUA), and perfluorododecanoic acid (PFDoA). The analytical method used has been described in detail (Kuklenyik et al. 2005). Briefly, without protein precipitation, only dilution with 0.1 M formic acid, one aliquot of 100 μL of serum was injected into a commercial column switching system allowing for concentration of the analytes on a C18 solid-phase extraction column. This column was placed automatically in front of a C8 analytical high-performance liquid chromatography column for chromatographic separation of the analytes. Detection and quantification were done using negative-ion TurboIonSpray ionization, a variant of electrospray ionization, tandem mass spectrometry. Three isotope-labeled internal standards were used for quantification: 18O2-PFOSA, 18O2-PFOS, and 13C2-PFOA. To compensate for the lack of isotope-labeled internal standards for the other analytes and account for matrix effects, the calibration standards were spiked into calf serum. Spiked serum was analyzed repeatedly to determine the limit of detection (LOD), accuracy, and precision of the method. LOD was calculated as 3S0, where S0 is the standard deviation as the concentration approaches zero (Taylor 1987). LOD was 0.2 nanograms per milliliter (ng/mL), except for PFHxS (0.1 ng/mL) and PFOSA (0.05 ng/mL). The standard accuracies (77%-109%) and their relative standard deviations (5%-24%) were obtained at three spike levels (LOD, 1.25 ng/mL and 12.5 ng/mL) (Kuklenyik et al. 2005). To correct for the endogenous PFOS present in the calf serum, we increased the calculated PFOS concentrations by 0.6 ng/mL. No corrections were applied to the other PFC.concentrations (Kuklenyik et al. 2005).

Data Processing and Editing

Specimens were processed, stored, and shipped to DLS, NCEH, CDC (Atlanta, Georgia). Detailed specimen collection and processing instructions are discussed in the NHANES LPM. Read the LABDOC file for detailed data processing and editing protocols. The analytical method is described in detail in a peer-reviewed publication (Kuklenyik et al. 2005).

Laboratory Quality Assurance and Monitoring

CDC’s laboratory is CLIA ‘88 certified and practices all quality control (QC) and assurance procedures dictated by this certification. Serum concentrations of PFCs currently have no known clinical significance other than indicating exposure to PFCs prior to specimen collection in 1999-2000. Therefore, no reports will be forwarded to NHANES survey participants.

QC procedures included the daily analysis of characterized serum pools and the periodic analysis of proficiency testing materials. Low-concentration (QCL; ~3 ng/mL to ~9 ng/mL, depending upon the analyte) and high-concentration (QCH; ~10 ng/mL to ~30 ng/mL, depending upon the analyte) QC materials were prepared from a base calf serum pool, dispensed in 3-mL aliquots and stored at −20 °C. QC materials were characterized through repeated measurements spanning at least 3 weeks, to define the mean concentrations and the 95% and 99% control limits of PFCs. The coefficients of variation of 30 repeated measurements for each serum pool ranged between 6% and 16% for all analytes (Kuklenyik et al. 2005). Each analytical batch of NHANES samples also included 9 calibration standards, 2 QCH, 2 QCL, 2 reagent blanks, and 1 serum blank. The concentrations of the two QCH and the two QCL were averaged to obtain one measurement of QCH and of QCL per batch; these concentrations were evaluated using standard statistical probability rules.

Analytic Notes

The analysis of NHANES 1999–2000 PFCs data must be conducted with the key survey design and basic demographic variables. The NHANES 1999–2000 Household Questionnaire Data files contain demographic data, health indicators, and other related information collected during household interviews. They also contain all survey design variables and sample weights. The phlebotomy file includes auxiliary information such as the conditions precluding venipuncture. The household questionnaire and phlebotomy files may be linked to the laboratory data file using the unique survey participant identifier SEQN.

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 1 YEARS - 150 YEARS

SEPAHLC - Surplus sera EPAH comment code

Variable Name:
SEPAHLC
SAS Label:
Surplus sera EPAH comment code
English Text:
Surplus sera EPAH comment code
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 1483 1483
1 Below lower detection limit 108 1591
. Missing 0 1591

SEPAH - Surplus sera EPAH result (ng/ml)

Variable Name:
SEPAH
SAS Label:
Surplus sera EPAH result (ng/ml)
English Text:
Surplus sera 2-(N-ethyl-perfluorooctane sulfonamido) acetate (EPAH) result (ng/ml)
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.2 to 24.6 Range of Values 1591 1591
. Missing 0 1591

SMPAHLC - Surplus sera MPAH comment code

Variable Name:
SMPAHLC
SAS Label:
Surplus sera MPAH comment code
English Text:
Surplus sera MPAH comment code
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 1553 1553
1 Below lower detection limit 38 1591
. Missing 0 1591

SMPAH - Surplus sera MPAH result (ng/ml)

Variable Name:
SMPAH
SAS Label:
Surplus sera MPAH result (ng/ml)
English Text:
Surplus sera 2-(N-methyl-perfluorooctane sulfonamido) acetate (MPAH) result (ng/ml)
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.2 to 38.4 Range of Values 1591 1591
. Missing 0 1591

SPFDELC - Surplus sera PFDE comment code

Variable Name:
SPFDELC
SAS Label:
Surplus sera PFDE comment code
English Text:
Surplus sera PFDE comment code
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 480 480
1 Below lower detection limit 1111 1591
. Missing 0 1591

SPFDE - Surplus sera PFDE result (ng/ml)

Variable Name:
SPFDE
SAS Label:
Surplus sera PFDE result (ng/ml)
English Text:
Surplus sera perfluorodecanoate (PFDE) result (ng/ml)
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.2 to 7.8 Range of Values 1591 1591
. Missing 0 1591

SPFDOLC - Surplus sera PFDO comment code

Variable Name:
SPFDOLC
SAS Label:
Surplus sera PFDO comment code
English Text:
Surplus sera PFDO comment code
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 11 11
1 Below lower detection limit 1580 1591
. Missing 0 1591

SPFDO - Surplus sera PFDO result (ng/ml)

Variable Name:
SPFDO
SAS Label:
Surplus sera PFDO result (ng/ml)
English Text:
Surplus sera perfluorododecanoate (PFDO) result (ng/ml)
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.2 to 1 Range of Values 1591 1591
. Missing 0 1591

SPFHPLC - Surplus sera PFHP comment code

Variable Name:
SPFHPLC
SAS Label:
Surplus sera PFHP comment code
English Text:
Surplus sera PFHP comment code
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 224 224
1 Below lower detection limit 1367 1591
. Missing 0 1591

SPFHP - Surplus sera PFHP result (ng/ml)

Variable Name:
SPFHP
SAS Label:
Surplus sera PFHP result (ng/ml)
English Text:
Surplus sera perfluoroheptanoate (PFHP) result (ng/ml)
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.4 to 4.2 Range of Values 1591 1591
. Missing 0 1591

SPFHSLC - Surplus sera PFHS comment code

Variable Name:
SPFHSLC
SAS Label:
Surplus sera PFHS comment code
English Text:
Surplus sera PFHS comment code
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 1587 1587
1 Below lower detection limit 4 1591
. Missing 0 1591

SPFHS - Surplus sera PFHS result (ng/ml)

Variable Name:
SPFHS
SAS Label:
Surplus sera PFHS result (ng/ml)
English Text:
Surplus sera perfluorohexane sulfonate (PFHS) result (ng/ml)
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.1 to 46.5 Range of Values 1591 1591
. Missing 0 1591

SPFNALC - Surplus sera PFNA comment code

Variable Name:
SPFNALC
SAS Label:
Surplus sera PFNA comment code
English Text:
Surplus sera PFNA comment code
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 1524 1524
1 Below lower detection limit 67 1591
. Missing 0 1591

SPFNA - Surplus sera PFNA result (ng/ml)

Variable Name:
SPFNA
SAS Label:
Surplus sera PFNA result (ng/ml)
English Text:
Surplus sera perfluorononanoate (PFNA) result (ng/ml)
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.1 to 13.7 Range of Values 1591 1591
. Missing 0 1591

SPFOALC - Surplus sera PFOA comment code

Variable Name:
SPFOALC
SAS Label:
Surplus sera PFOA comment code
English Text:
Surplus sera PFOA comment code
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 1590 1590
1 Below lower detection limit 1 1591
. Missing 0 1591

SPFOA - Surplus sera PFOA result (ng/ml)

Variable Name:
SPFOA
SAS Label:
Surplus sera PFOA result (ng/ml)
English Text:
Surplus sera perfluorooctanoate (PFOA) result (ng/ml)
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.1 to 123 Range of Values 1591 1591
. Missing 0 1591

SPFOSLC - Surplus sera PFOS comment code

Variable Name:
SPFOSLC
SAS Label:
Surplus sera PFOS comment code
English Text:
Surplus sera PFOS comment code
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 1591 1591
1 Below lower detection limit 0 1591
. Missing 0 1591

SPFOS - Surplus sera PFOS result (ng/ml)

Variable Name:
SPFOS
SAS Label:
Surplus sera PFOS result (ng/ml)
English Text:
Surplus sera perfluorooctane sulfonate (PFOS) result (ng/ml)
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.3 to 298 Range of Values 1591 1591
. Missing 0 1591

SPFSALC - Surplus sera PFSA comment code

Variable Name:
SPFSALC
SAS Label:
Surplus sera PFSA comment code
English Text:
Surplus sera PFSA comment code
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 1556 1556
1 Below lower detection limit 35 1591
. Missing 0 1591

SPFSA - Surplus sera PFSA result (ng/ml)

Variable Name:
SPFSA
SAS Label:
Surplus sera PFSA result (ng/ml)
English Text:
Surplus sera perfluorooctane sulfonamide (PFSA) result (ng/ml)
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.1 to 9.6 Range of Values 1591 1591
. Missing 0 1591

SPFUALC - Surplus sera PFUA comment code

Variable Name:
SPFUALC
SAS Label:
Surplus sera PFUA comment code
English Text:
Surplus sera PFUA comment code
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above the detection limit 237 237
1 Below lower detection limit 1354 1591
. Missing 0 1591

SPFUA - Surplus sera PFUA result (ng/ml)

Variable Name:
SPFUA
SAS Label:
Surplus sera PFUA result (ng/ml)
English Text:
Surplus sera perfluoroundecanoate (PFUA) result (ng/ml)
Target:
Both males and females 1 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.2 to 4 Range of Values 1591 1591
. Missing 0 1591