• Component Description
• Eligible Sample
• Description of Laboratory Methodology
• Laboratory Quality Assurance and Monitoring
• Data Processing and Editing
• Analytic Notes
• References
• Codebook
  • SEQN - Respondent sequence number
  • WTSSBG2Y - Surplus specimen B 11-12 2 year weights
  • SSDPHP - Diphenyl phosphate (ug/L)
  • SSDPHPL - Diphenyl phosphate cmt code
  • SSBDCPP - Bis(1,3-dichloro-2-propyl) phos (ug/L)
  • SSBDCPPL - Bis(1,3-dichloro-2-propyl) phos cmt cd
  • SSBCPP - Bis(1-chloro-2-propyl) phosphate (ug/L)
  • SSBCPPL - Bis(1-chloro-2-propyl) phosphate cmt cd
  • SSBCEP - Bis(2-chloroethyl) phosphate (ug/L)
  • SSBCEPL - Bis(2-chloroethyl) phosphate cmt cd
  • SSDCP - Di-cresyl phosphates (ug/L)
  • SSDCPL - Di-cresyl phosphates cmt code
  • SSDBUP - Dibutyl phosphate (ug/L)
  • SSDBUPL - Dibutyl phosphate cmt code
  • SSDBZP - Dibenzyl phosphate (ug/L)
  • SSDBZPL - Dibenzyl phosphate cmt code
  • SSTBBA - 2,3,4,5-tetrabromobenzoic acid (ug/L)
  • SSTBBAL - 2,3,4,5-tetrabromobenzoic acid cmt cd

National Health and Nutrition Examination Survey

2011-2012 Data Documentation, Codebook, and Frequencies

Flame Retardants - Urine (Surplus) (SSFR_G)

Data File: SSFR_G.xpt

First Published: August 2019

Last Revised: April 2022

Component Description

Flame retardants (FRs) are either additive or reactive ingredients applied to household and consumer products to reduce the products flammability, and to meet state and federal fire safety standards and regulations. Until recently, a dominant class of FR additives used for household products was polybrominated diphenyl ethers (PBDEs), which are persistent and can accumulate in the environment (de Wit 2002; Law et al.2006, Stapleton et al. 2012). Flame retardant formulations containing chlorinated and non-chlorinated organophosphates and non-PBDE brominated chemicals have entered consumers’ markets as PBDEs have been phased-out in many countries (van der Veen and de Boer 2012). Some of these non-PBDE compounds used in flame retardant formulations are: triphenyl phosphate, tris(1,3-dichloro-2-propyl) phosphate, tris(1-chloro-2-propyl) phosphate, tris(2-chloroethyl) phosphate, tri-cresyl phosphates, tributyl phosphate, tribenzyl phosphate, and 2-ethylhexyl-2,3,4,5-tetrabromobenzoate. We recently developed a method to measure metabolites of these compounds that can be used as exposure biomarkers: diphenyl phosphate, bis(1,3-dichloro-2-propyl) phosphate), bis(1-chloro-2-propyl) phosphate, bis(2-chloroethyl) phosphate, di-cresyl phosphates, dibutyl phosphate, dibenzyl phosphate, and 2,3,4,5-tetrabromobenzoic acid.

Eligible Sample

One-third subsample of participants aged 6+ years from NHANES 2011-2012 with stored urine.

Description of Laboratory Methodology

The method uses 0.2 mL urine and is based on enzymatic hydrolysis of urinary conjugates of the target analytes, automated off-line solid phase extraction, reversed phase high-performance liquid chromatography separation, and isotope dilution-electrospray ionization tandem mass spectrometry detection (Jayatilaka et al. 2019.

Laboratory Quality Assurance and Monitoring

The analytical measurements were conducted following strict quality control/quality assurance CLIA guidelines. Along with the study samples, each analytical run included high- and low-concentration quality control materials (QCs) and reagent blanks to assure the accuracy and reliability of the data. The concentrations of the high-concentration QCs and the low-concentration QCs, averaged to obtain one measurement of high-concentration QC and low-concentration QC for each run, were evaluated using standard statistical probability rules (Caudill et al. 2008).

Data Processing and Editing

Data were received after all analyses were complete. The data were not edited.

Data Access: All data are publicly available.

Analytic Notes

Detection Limits

The detection limits were constant for all of the analytes in the data set. Two variables are provided for each analyte. The variable name ending in “L” (ex., SSDPHPL) 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. For analytes with analytic results below the limit of detection (ex., SSDPHPL=1), an imputed fill value was placed in the analyte results field. This value is the limit of detection divided by square root of 2 (LOD/√2). The other variable prefixed SS (ex., SSDPHP) provides the analytic result for that analyte.

The limits of detection (LOD, in µg/L) for DPhP, BDCPP, BCPP, BCEtP, DCP, DBuP, DBzP and TBBA are:

Interferences:

Blanks in an analyte results field represent missing values in cases when the presence of interferences precluded obtaining a valid numeric result.

Subsample Weights

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. Previous versions of this data file included a sample weight variable (WTSB2YR) but when observations were removed from this data file, a new sample weight was created, and a new sample weight variable was added to this data file  (WTSSBG2Y). Please refer to the NHANES Analytic Guidelines and the on-line NHANES Tutorial for further details on the use of sample weights and other analytic issues.

References

• Caudill SP, Schleicher RL, Pirkle JL. (2008). Multi-rule quality control for the age-related eye disease study. Statist Med 27: 4094-4106.
• de Wit CA (2002). An overview of brominated flame retardants in the environment. Chemosphere 46 (5):583-624.
• Jayatilaka NK, Restrepo P, Davis Z, Vidal M, Calafat AM, Ospina M. (2019). Quantification of 16 urinary biomarkers of exposure to flame retardants, plasticizers, and organophosphate insecticides by solid phase extraction- high performance liquid chromatography-tandem mass spectrometry. Submitted for publication.
• Law RJ, Allchin CR, de Boer J, Covaci A, Herzke D, Lepom P, et al. (2006). Levels and trends of brominated flame retardants in the European environment. Chemosphere 64:187–208.
• Stapleton HM, Sharma S, Getzinger G, Ferguson PL, Gabriel M, Webster TF, Blum A (2012). Novel and High Volume Use Flame Retardants in US Couches Reflective of the 2005 PentaBDE Phase Out. Environmental Science & Technology 46 (24):13432-13439.
• van der Veen I, de Boer J (2012). Phosphorus flame retardants: Properties, production, environmental occurrence, toxicity and analysis. Chemosphere 88 (10):1119-1153.

Codebook and Frequencies