Table of Contents

Locator Record

Title: Environmental Pesticides (PP_E )
Contact Number: 1-866-441-NCHS
Years of Content: 2007 - 2008
First Published: October, 2010
Revised: September, 2011
Access Constraints: None
Use Constraints: None
Geographic Coverage: National
Subject:Environmental Pesticides (2,4-dichlorophenol, 2,5-dichlorophenol, ortho-phenylphenol, 2,4,5-trichlorophenol, and 2,4,6-trichlorophenol )
Record Source: NHANES 2007 - 2008
Survey Methodology: NHANES 2007 - 2008 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

Biomonitoring of urinary environmental phenols is used to determine prevalence of human exposure and the relevance of human exposure in public health. The sources of human exposure to these phenolic compounds include industrial pollution, pesticides, food, and drinking water.

Chlorophenols have been used in the wood preservation industry, as intermediates in the production of pesticides, and as disinfectants or fungicides for industrial and indoor home use. Clorophenols are also by-products of waste water and municipal drinking water disinfection with chlorine. The manufacture of other chlorinated aromatic compounds can produce chlorophenols as byproducts. 2,4-Dichlorophenol sources include water chlorination, wood pulp bleaching, pesticide manufacturing, and environmental degradation of the herbicide 2.4-diphenoxyacetic acid. 2,5-Dichlorophenol is a metabolite of 1,4-dichlorobenzene and has industrial uses including dye and chemical synthesis and resin production. 2,4,5- and 2,4,6-Trichlorophenol are metabolites of several organochlorine pesticides. Although they may still be used in production of certain fungicides, these chemicals are no longer commercially manufactured but may occur in small amounts in chlorinated drinking water, and they may be produced during combustion of natural materials or detected in chlorinated waste water. Orthophenylphenol is an antimicrobial agent used in agriculture, with limited use on food crops, but used as a fungicide on ornamental plants and turf and as a wood and paint preservative. Thus, there are numerous sources for human exposure to these chlorophenols, encompassing food, drinking water, pesticide use, and contact with contaminated or treated materials. Measurement of urinary metabolites of chlorophenols is useful to assess recent human exposure.

Eligible Sample

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

Description of Laboratory Methodology

Bisphenol A (BPA) and Alkylphenols (APs) have been previously measured in biological matrixes by using gas chromatography (GC) or high performance liquid chromatography (HPLC) coupled with different detection techniques. To achieve enhanced sensitivity and selectivity, the phenols have been derivatized to alkyl or acyl derivatives before GC-mass spectrometry (GC/MS) analysis. We have developed a sensitive method for measuring BPA, 4-tert-octylphenol (tOP), benzophenone-3 (BP-3), one chlorophenols triclosan, and four parabens. The method uses solid phase extraction (SPE) coupled on-line to HPLC and tandem mass spectrometry (MS/MS). With the use of isotopically labeled internal standards, the detection limits in 100 μL of urine are 0.1-2 nanograms per milliliter (ng/mL), sufficient for measuring urinary levels of phenols in non-occupationally exposed subjects.

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 contract laboratories. In the MEC, these methods include performing blind split samples collected on “dry run” sessions. In addition, contract laboratories randomly perform repeat testing on 2.0% of all specimens.

NCHS developed and distributed a quality control protocol for all the contract laboratories which outlined the Westgard rules used 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 and Westat 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 Environmental Health Laboratory Sciences’ quality control and quality assurance performance criteria for accuracy and precision, similar to specifications outlined by Westgard et al. (1981).

Analytic Notes

Subsample weights

Measures of urinary environmentals 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 laboratory data must be conducted with the key survey design and basic demographic variables. The NHANES 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 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.

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 - Environmental B 2 year weights

Variable Name:
WTSB2YR
SAS Label:
Environmental B 2 year weights
English Text:
Environmental C 2 year weights
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 to 533131.16757 Range of Values 2718 2718
. Missing 0 2718

URX14D - 2,5-dichlorophenol (ug/L) result

Variable Name:
URX14D
SAS Label:
2,5-dichlorophenol (ug/L) result
English Text:
2,5-dichlorophenol (ug/L) result
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.14 to 47200 Range of Values 2604 2604
. Missing 114 2718

URD14DLC - 2,5-dichlorophenol comment

Variable Name:
URD14DLC
SAS Label:
2,5-dichlorophenol comment
English Text:
2,5-dichlorophenol comment
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 2577 2577
1 Below lower detection limit 27 2604
. Missing 114 2718

URXOPP - O-Phenyl phenol (ug/L) result

Variable Name:
URXOPP
SAS Label:
O-Phenyl phenol (ug/L) result
English Text:
O-Phenyl phenol result
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.07 to 20.3 Range of Values 2604 2604
. Missing 114 2718

URDOPPLC - O-Phenyl phenol comment

Variable Name:
URDOPPLC
SAS Label:
O-Phenyl phenol comment
English Text:
O-Phenyl phenol comment
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 337 337
1 Below lower detection limit 2267 2604
. Missing 114 2718

URXDCB - 2,4-dichlorophenol (ug/L) result

Variable Name:
URXDCB
SAS Label:
2,4-dichlorophenol (ug/L) result
English Text:
2,4-dichlorophenol (ug/L) result
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.14 to 933 Range of Values 2604 2604
. Missing 114 2718

URDDCBLC - 2,4-dichlorophenol comment

Variable Name:
URDDCBLC
SAS Label:
2,4-dichlorophenol comment
English Text:
2,4-dichlorophenol comment
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 2380 2380
1 Below lower detection limit 224 2604
. Missing 114 2718

URX1TB - 2,4,5-trichlorophenol (ug/L) result

Variable Name:
URX1TB
SAS Label:
2,4,5-trichlorophenol (ug/L) result
English Text:
2,4,5-trichlorophenol (ug/L) result
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.07 to 6.8 Range of Values 2604 2604
. Missing 114 2718

URD1TBLC - 2,4,5-trichlorophenol comment

Variable Name:
URD1TBLC
SAS Label:
2,4,5-trichlorophenol comment
English Text:
2,4,5-trichlorophenol comment
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 763 763
1 Below lower detection limit 1841 2604
. Missing 114 2718

URX3TB - 2,4,6-trichlorophenol (ug/L) result

Variable Name:
URX3TB
SAS Label:
2,4,6-trichlorophenol (ug/L) result
English Text:
2,4,6-trichlorophenol (ug/L) result
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.35 to 61.8 Range of Values 2604 2604
. Missing 114 2718

URD3TBLC - 2,4,6-trichlorophenol comment

Variable Name:
URD3TBLC
SAS Label:
2,4,6-trichlorophenol comment
English Text:
2,4,6-trichlorophenol comment
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 695 695
1 Below lower detection limit 1909 2604
. Missing 114 2718

URXUCR - Urinary creatinine (mg/dL)

Variable Name:
URXUCR
SAS Label:
Urinary creatinine (mg/dL)
English Text:
Urinary creatinine (mg/dL)
Target:
Both males and females 6 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
5 to 490 Range of Values 2623 2623
. Missing 95 2718