Table of Contents

Component Description

Lead is a known environmental toxin that has been shown to deleteriously affect the nervous, hematopoietic, endocrine, renal, and reproductive systems. In young children, lead exposure is a particular hazard because children more readily absorb lead than do adults, and children's developing nervous systems also make them more susceptible to the effects of lead. Since first measuring blood lead during the 1976–1980 survey, NHANES has been the cornerstone for lead exposure surveillance in the U.S.

In 1999, NHANES began to collect dust samples from the homes of children 1–5 years of age to be tested for the presence of lead. Lead in dust is most often the result of old, peeling, or chipping lead-based paint. As part of the household visit, NHANES interviewers collected separate dust-wipe samples from the floor and window sill of one room in the home. Signing of a special informed consent was required prior to the collection.

Eligible Sample

Eligible survey participants were households with children 1–5 years of age.

Description of Laboratory Methodology

The preparation procedure for dust-wipe sample digestion involves the quantitative transfer of the sample from the container into a beaker, and then the subsequent addition of nitric and hydrochloric acids and hot-plate heating. The procedure is described in the Appendix of the Guidelines for the Evaluation and Control of Lead-Based Paint Hazards in Housing. The technique does not involve complete digestion of the sample, but does entail leaching of the lead (Pb) from the collected dust. Recovery of the method is based and evaluated on the results of matrix (wipe) spiked National Institute of Standards and Technology (NIST) quality control samples. The lead content of the digestate is determined by using a PerkinElmer Flame Atomic Absorption Spectrometer (FAAS) Model 5000 or 5100 for all window dust-wipe samples and a PerkinElmer Graphite Furnace Atomic Absorption Spectrometer (GFAAS) Model 5100 for all floor dust-wipe samples. However, a floor dust sample whose value was found to be 5 μg or greater by GFAAS are re-analyzed by FAAS and that value is reported.

Data Processing and Editing

Detailed specimen collection instructions are discussed in the NHANES Household Interview Procedures Manual, Chapter 7. This chapter specifies the procedure to be used for preparation of the window and floor, specimen collection, labeling, and conditions for specimen transport.

Laboratory Quality Assurance and Monitoring

Additional dust samples (either window sill or floor) were taken in 5% of households as part of the quality control procedures. A field blank was also collected. Results from these quality control measures are not included as part of this data file.

For years 2003-2004, the floor samples (n=57) had a 96.6% (+/-3.2%) recovery at an average spike level of 65.41 (sd 12.74) μg. The window sill samples (n=61) revealed a 96.6% (+/-3.7%) recovery at an average spike level of 64.83 (sd 12.44) μg.

Analytic Notes

This data file includes the laboratory values as well as variables related to characteristics of the room where the samples were taken, and other factors relevant to data collection.

DCDINDEX

The variable identifies the index child designated for dust collection. Descriptive data about the home environment and the dust samples were collected for one child in the household. In homes where more than one child aged 1-5 years resided, the descriptive and laboratory data for the index child were assigned to all other children in the age group.

DCDSTAT

This variable indicates which samples are available. In some households, only a single sample (either window sill or floor) was taken. This variable was derived based on final results from the laboratory.

DCD030

The room where the sample was taken was most often the same room where the child spent most of his or her time in the home. In editing this variable, some responses from the “other” category were re-coded to pre-existing categories, and additional categories were created.

DCD070A

Carpet in room selected for sample. Response categories ordering from the original question were reordered for purposes of clarification and consistency.

It is advised that this data file should be combined with additional years of data because data are available on a small subset of the survey population. This data file was designed to be used primarily at the SP level with other data collected in the MEC. Please note, data were retained for persons who took part in the household interview (including dust collection) but were not examined at the MEC.

LBXDFS

Floor sample, lead dust result (μg/sq ft), by GFAAS. All floor dust results are derived from a 1 square foot area, the size of the template used for the sample collection. If a floor sample was collected but the result is missing for LBXDFS, use LBXDFSF. Use LBDDFSLC, laboratory comment code, to determine values below the limit of detection.

LBXDFSF

Floor sample, lead dust result (μg/sq ft) by FAAS. All floor dust results are derived from a 1 square foot area, the size of the template used for the sample collection. If a floor sample was collected but the result is missing for LBXDFSF, use LBXDFS. Use LBDD3LC, laboratory comment code, to determine values below the limit of detection.

LBXDDWS

Window sill sample, lead dust result (μg/sq ft). All window sill dust results were calculated based on the measured length and width of the window sill area. Use LBDDWSLC, laboratory comment code, to determine values below the limit of detection.

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 - 5 YEARS

DCDINDEX - Index child for sampling

Variable Name:
DCDINDEX
SAS Label:
Index child for sampling
English Text:
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Index Child 927 927
2 Other Household Child 340 1267
. Missing 0 1267

DCDSTAT - Dust sample status

Variable Name:
DCDSTAT
SAS Label:
Dust sample status
English Text:
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Floor Only 264 264
2 Window Only 0 264
3 Floor and Window 931 1195
. Missing 72 1267

DCD030 - Room where samples taken

Variable Name:
DCD030
SAS Label:
Room where samples taken
English Text:
Room where samples taken
English Instructions:
ENTER LOCATION OF SAMPLE
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
2 Living Room/Family Room/Den 971 971
3 Dining Room 19 990
4 Kitchen 23 1013
5 Bedroom 155 1168
7 Another room 27 1195
. Missing 72 1267

DCD070A - Room selected was floor carpeted

Variable Name:
DCD070A
SAS Label:
Room selected was floor carpeted
English Text:
Indicates whether floor was carpeted in room-floor sample
English Instructions:
ENTER ROOM CARPET CODE: CAPI EDIT: IF "NO CARPET" (CODE 2) IS SELECTED, NO OTHER CODE MAY BE SELECTED.
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 931 931
2 No 264 1195
. Missing 72 1267

DCQ070B - Room selected had floor mat

Variable Name:
DCQ070B
SAS Label:
Room selected had floor mat
English Text:
Indicates whether mat was found in room-floor sample
English Instructions:
ENTER ROOM CARPET CODE: CAPI EDIT: IF "NO CARPET" (CODE 2) IS SELECTED, NO OTHER CODE MAY BE SELECTED.
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 12 12
2 No 1183 1195
. Missing 72 1267

DCQ070C - Room selected had area rug

Variable Name:
DCQ070C
SAS Label:
Room selected had area rug
English Text:
Indicates whether area rug was found in room-floor sample
English Instructions:
ENTER ROOM CARPET CODE: CAPI EDIT: IF "NO CARPET" (CODE 2) IS SELECTED, NO OTHER CODE MAY BE SELECTED.
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 160 160
2 No 1035 1195
. Missing 72 1267

DCQ070D - Room selected had wall-wall carpeting

Variable Name:
DCQ070D
SAS Label:
Room selected had wall-wall carpeting
English Text:
If there was wall to wall carpet-floor sample
English Instructions:
ENTER ROOM CARPET CODE: CAPI EDIT: IF "NO CARPET" (CODE 2) IS SELECTED, NO OTHER CODE MAY BE SELECTED.
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 813 813
2 No 382 1195
. Missing 72 1267

DCQ090 - Carpet pile depth

Variable Name:
DCQ090
SAS Label:
Carpet pile depth
English Text:
Depth of carpeting-floor sample
English Instructions:
ENTER CARPET PILE DEPTH:
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Low pile 823 823
2 High pile 75 898
3 Not applicable 33 931
. Missing 336 1267

DCQ160 - Surface condition for floor dust sample

Variable Name:
DCQ160
SAS Label:
Surface condition for floor dust sample
English Text:
Surface condition for floor dust sample
English Instructions:
CAPI EDIT: IF "NO CARPET" (CODE 2) HAS BEEN SELECTED IN DCD.070A, DO NOT ALLOW SELECTION OF "CARPETED" (CODE 3) IN DCQ.160.
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Smooth and Cleanable 272 272
2 Not Smooth and Cleanable 23 295
3 Carpet 87 382
. Missing 885 1267

DCQ240 - Window sill finished

Variable Name:
DCQ240
SAS Label:
Window sill finished
English Text:
Window sill finished
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 852 852
2 No 79 931
. Missing 336 1267

DCQ250 - Surface condition for sill dust sample

Variable Name:
DCQ250
SAS Label:
Surface condition for sill dust sample
English Text:
Surface condition for sill dust sample
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Smooth and Cleanable 866 866
2 Not Smooth and Cleanable 65 931
. Missing 336 1267

DCQ400 - Room cleanliness

Variable Name:
DCQ400
SAS Label:
Room cleanliness
English Text:
INTERVIEWER OBSERVATION: ROOM CLEANLINESS
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Dirtier than average 181 181
2 Average 722 903
3 Cleaner than average 291 1194
. Missing 73 1267

DCQ410 - Room clutter

Variable Name:
DCQ410
SAS Label:
Room clutter
English Text:
INTERVIEWER OBSERVATION: ROOM CLUTTER
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Very cluttered (nothing in place) 175 175
2 Average amount of clutter 676 851
3 Organized (nothing out of place) 343 1194
. Missing 73 1267

LBXDFS - Floor, GFAAS (ug/sq.ft.)

Variable Name:
LBXDFS
SAS Label:
Floor, GFAAS (ug/sq.ft.)
English Text:
Floor result in micrograms per square feet by graphite furnace atomic absorption spectrophotometric method.
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.11 to 8.5 Range of Values 1123 1123
. Missing 144 1267

LBXDFSF - Floor, FAAS (ug/sq. ft.)

Variable Name:
LBXDFSF
SAS Label:
Floor, FAAS (ug/sq. ft.)
English Text:
Floor result in micrograms per square feet by flame atomic absorption spectrophotometric method.
English Instructions:
If the floor sample result by the GFAAS method is >5 then it is measured by the FAAS method. Only the FAAS method result is reported.
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1.1 to 126.6 Range of Values 72 72
. Missing 1195 1267

LBDDWS - Window, FAAS (ug/sq. ft.)

Variable Name:
LBDDWS
SAS Label:
Window, FAAS (ug/sq. ft.)
English Text:
Window result in micrograms per square feet by flame atomic absorption spectrophotometric method.
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.65 to 4493.96 Range of Values 931 931
. Missing 336 1267

LBDDFSLC - Lead dust floor (GFAAS) comment code

Variable Name:
LBDDFSLC
SAS Label:
Lead dust floor (GFAAS) comment code
English Text:
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above limit of detection 958 958
1 Below limit of detection 165 1123
. Missing 144 1267

LBDD3LC - Lead dust floor (FAAS) comment code

Variable Name:
LBDD3LC
SAS Label:
Lead dust floor (FAAS) comment code
English Text:
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above limit of detection 72 72
1 Below limit of detection 0 72
. Missing 1195 1267

LBDDWSLC - Lead dust window sill comment code

Variable Name:
LBDDWSLC
SAS Label:
Lead dust window sill comment code
English Text:
Target:
Both males and females 1 YEARS - 5 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 At or above limit of detection 501 501
1 Below limit of detection 430 931
. Missing 336 1267