Volatile Organic Compounds and Trihalomethanes/MTBE (Whole Blood)
Volatile organic compounds (VOCs) are a large group of chemicals that have been used as solvents, degreasers, and cleaning agents in industry and consumer products. Many of the VOCs were found to contaminate ground water and drinking water sources. Because of human health concerns, these VOCs have been banned or restricted from most uses.
The halogenated solvents are VOCs consisting of a hydrocarbon chain or one hydrocarbon substituted with one or more chlorine or bromine atoms. Most of these chemicals are used as degreasers and solvents in various products, such as paint. In the past, 1,1,1-trichloroethane was used as a dry cleaning agent, insect fumigant, and solvent in consumer products. Methylene chloride, tetrachloroethene, and trichloroethene are other VOCs that were widely used in the past.
Benzene, toluene, ethylbenzene, xylene, and styrene, collectively referred to as BTEXS, are components of tobacco smoke. Along with 2,5-dimethylfuran, these VOCs are usually detected in the blood of cigarette smokers at higher levels than in non-smokers. Chlorobenzene (monochlorobenzene) and the three dichlorobenzenes are halogenated aromatic hydrocarbons primarily used in industrial and chemical synthetic processes. Chlorobenzene has been used to produce DDT, phenol, and nitrobenzene. The dichlorobenzenes are also chemical intermediates in the synthesis of dyes, pesticides, and other industrial products. 1,4-Dichlorobenzene (para-dichlorobenzene) is used also as a moth repellent and as a deodorizer. Disinfection by-products (DBP), including bromodichloromethane, dibromochloromethane, bromoform, and chloroform are formed when chlorine interacts with natural organic materials found in water. Primary sources of DBPs are chlorinated drinking water and recreational water bodies, such as swimming pools.
The prevalence of disinfection by-products in drinking water supplies has raised concerns about possible adverse health effects from chronic exposure to these potentially carcinogenic compounds. Methyl-tert-butyl ether (MTBE) was used as an additive to replace lead in gasoline, but its use was banned after widespread ground water contamination was discovered.
Inhalation is the most common VOC route of exposure in the general population, including indoor sources such as paints, adhesives, cleaning solutions, and aerosolized insecticide sprays; industries producing these solvents; and contaminated waste disposal sites. Drinking water may contribute to exposure when underground drinking water supplies are contaminated. After they are absorbed in the body, VOCs are rapidly eliminated in exhaled breath, or may be rapidly metabolized and eliminated in the urine.
Participants aged 18 years and older, who met the regular one-half subsample selection criteria, were included in this special subsample. Additionally, to oversample adult smokers, those participants aged 18 years and older, not in the regular one-half subsample, who smoked at least 100 cigarettes in their entire lifetime (SMQ020=1) and now smoke cigarettes every day (SMQ040=1), were also included in this special subsample.
An automated analytical method was developed using capillary gas chromatography (GC) and mass spectrometry (MS) with selected-ion monitoring (SIM) detection and isotope-dilution. This method quantifies levels of individual VOCs and Trihalomethanes (THMs) and methyl tert-butyl ether (MTBE) in whole blood to low-parts-per-trillion range. Because non-occupationally exposed individuals have blood VOC concentrations within this range, this method is applicable for determining these quantities and investigating cases of sustained or recent low-level exposure.
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 2015-2016 cycle.
Volatile Organic Compounds (VOCs) & Trihalomethanes/MTBE Laboratory Procedure Manual (September 2018)
Whole blood specimens were processed, stored, and shipped to 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 Procedures Manual (LPM). Vials are stored under appropriate refrigerated (2-8°C) conditions until they are shipped to 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 on “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 Division of Laboratory Services’ quality control and quality
assurance performance criteria for accuracy and precision, similar to the
Westgard rules (Caudill et al., 2008).
The data were reviewed. Incomplete data or improbable values were sent to the performing laboratory for confirmation.
Refer to the 2015-2016 Laboratory Data Overview for general information on NHANES laboratory data.
Volatile Toxicant Questionnaire
A volatile toxicant questionnaire (VTQ) was administered on the mobile examination center (MEC), by trained interviewers, using the Computer-Assisted Personal Interview (CAPI) system. The VTQ section includes data about the SP’s home, activities, amount of time spent in various locations, and exposure to different chemicals over the past 48 hours. This questionnaire data can be used in conjunction with the VOC laboratory dataset and found in the Volatile Toxicant Data File in the NHANES 2015-2016 Questionnaire Data section.
Subsample Weights
Whole blood VOCs were measured in a one-half subsample of participants 18 years and older. 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.
Demographic and Other Related Variables
The analysis of NHANES laboratory data must be conducted using the appropriate survey design and demographic variables. The NHANES 2015-2016 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, the time of venipuncture, and the conditions precluding 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
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 name ending in “LC” (ex., LBD2DFLC) indicates whether the result was below the limit of detection: “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 lower limit of detection (ex., LBD2DFLC=1), an imputed fill value was placed in the analyte results field. This value is the lower limit of detection divided by square root of 2 (LLOD/sqrt [2]). The other variable prefixed LBX (ex., LBX2DF) provides the analytic result for that analyte. All data are rounded to three significant figures or three decimal places, whichever is less precise.
Lower Limit of Detection (LLOD, in ng/mL) for Whole Blood VOCs:
VARIABLE NAME |
SAS LABEL |
LLOD |
LBX2DF |
Blood 2,5-Dimethylfuran (ng/mL) |
0.011 |
LBX4CE |
Blood 1,1,1,2-Tetrachloroethane (ng/mL) |
0.040 |
LBXV06 |
Blood Hexane (ng/mL) |
0.122 |
LBXV07N |
Blood Heptane (ng/mL) |
0.100 |
LBXV08N |
Blood Octane (ng/mL) |
0.100 |
LBXV1D |
Blood 1,2-Dichlorobenzene (ng/mL) |
0.025 |
LBXV2A |
Blood 1,2-Dichloroethane (ng/mL) |
0.010 |
LBXV3B |
Blood 1,3-Dichlorobenzene (ng/mL) |
0.025 |
LBXV4C |
Blood Tetrachloroethene (ng/mL) |
0.048 |
LBXVBF |
Blood Bromoform (ng/mL) |
0.008 |
LBXVBM |
Blood Bromodichloromethane (ng/mL) |
0.006 |
LBXVBZ |
Blood Benzene (ng/mL) |
0.024 |
LBXVBZN |
Blood Benzonitrile (ng/mL) |
0.150 |
LBXVC6 |
Blood Cyclohexane (ng/mL) |
0.020 |
LBXVCB |
Blood Chlorobenzene (ng/mL) |
0.011 |
LBXVCF |
Blood Chloroform (ng/mL) |
0.008 |
LBXVCM |
Blood Dibromochloromethane (ng/mL) |
0.005 |
LBXVCT |
Blood Carbon Tetrachloride (ng/mL) |
0.005 |
LBXVDB |
Blood 1,4-Dichlorobenzene (ng/mL) |
0.040 |
LBXVDE |
Blood 1,2-Dibromoethane (ng/ml) |
0.015 |
LBXVDEE |
Blood Diethyl Ether (ng/mL) |
0.040 |
LBXVDX |
Blood 1,4-Dioxane (ng/mL) |
0.500 |
LBXVEA |
Blood Ethyl Acetate (ng/mL) |
0.158 |
LBXVEB |
Blood Ethylbenzene (ng/mL) |
0.024 |
LBXVEC |
Blood Chloroethane (ng/mL) |
0.045 |
LBXVFN |
Blood Furan (ng/ml) |
0.025 |
LBXVIBN |
Blood Isobutyronitrile (ng/mL) |
0.040 |
LBXVIPB |
Blood Isopropylbenzene (ng/ml) |
0.040 |
LBXVMC |
Blood Methylene Chloride (ng/mL) |
0.250 |
LBXVMCP |
Blood Methylcyclopentane (ng/mL) |
0.020 |
LBXVME |
Blood MTBE (ng/mL) |
0.010 |
LBXVNB |
Blood Nitrobenzene (ng/mL) |
0.320 |
LBXVOX |
Blood o-Xylene (ng/mL) |
0.024 |
LBXVTC |
Blood Trichloroethene (ng/mL) |
0.012 |
LBXVTE |
Blood 1,1,1-Trichloroethane (ng/mL) |
0.010 |
LBXVTFT |
Blood ααα-Trifluorotoluene (ng/mL) |
0.040 |
LBXVTHF |
Blood Tetrahydrofuran (ng/mL) |
0.125 |
LBXVTO |
Blood Toluene (ng/mL) |
0.025 |
LBXVTP |
Blood 1,2,3-Trichloropropane (ng/ml) |
0.040 |
LBXVVB |
Blood Vinyl Bromide (ng/mL) |
0.045 |
LBXVXY |
Blood m-/p-Xylene (ng/mL) |
0.034 |
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.
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
5744.883139 to 533055.09127 | Range of Values | 3017 | 3017 | |
0 | No Lab Result | 249 | 3266 | |
. | Missing | 0 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.008 to 1.45 | Range of Values | 3010 | 3010 | |
. | Missing | 256 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 874 | 874 | |
1 | Below lower detection limit | 2136 | 3010 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 3010 | |
. | Missing | 256 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.028 | 0.028 | 3009 | 3009 | |
. | Missing | 257 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 0 | 0 | |
1 | Below lower detection limit | 3009 | 3009 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 3009 | |
. | Missing | 257 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.086 to 20.9 | Range of Values | 2772 | 2772 | |
. | Missing | 494 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 19 | 19 | |
1 | Below lower detection limit | 2753 | 2772 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2772 | |
. | Missing | 494 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.071 to 3.54 | Range of Values | 2914 | 2914 | |
. | Missing | 352 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 33 | 33 | |
1 | Below lower detection limit | 2881 | 2914 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2914 | |
. | Missing | 352 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.071 to 1.58 | Range of Values | 2928 | 2928 | |
. | Missing | 338 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 10 | 10 | |
1 | Below lower detection limit | 2918 | 2928 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2928 | |
. | Missing | 338 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.018 to 0.092 | Range of Values | 2935 | 2935 | |
. | Missing | 331 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 1 | 1 | |
1 | Below lower detection limit | 2934 | 2935 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2935 | |
. | Missing | 331 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.007 to 0.109 | Range of Values | 2970 | 2970 | |
. | Missing | 296 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 101 | 101 | |
1 | Below lower detection limit | 2869 | 2970 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2970 | |
. | Missing | 296 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.018 to 0.018 | Range of Values | 2970 | 2970 | |
. | Missing | 296 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 0 | 0 | |
1 | Below lower detection limit | 2970 | 2970 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2970 | |
. | Missing | 296 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.034 to 16 | Range of Values | 3017 | 3017 | |
. | Missing | 249 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 190 | 190 | |
1 | Below lower detection limit | 2827 | 3017 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 3017 | |
. | Missing | 249 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.006 to 0.139 | Range of Values | 2969 | 2969 | |
. | Missing | 297 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 271 | 271 | |
1 | Below lower detection limit | 2698 | 2969 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2969 | |
. | Missing | 297 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.004 to 0.068 | Range of Values | 3003 | 3003 | |
. | Missing | 263 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 528 | 528 | |
1 | Below lower detection limit | 2475 | 3003 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 3003 | |
. | Missing | 263 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.017 to 2.75 | Range of Values | 2966 | 2966 | |
. | Missing | 300 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 1441 | 1441 | |
1 | Below lower detection limit | 1525 | 2966 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2966 | |
. | Missing | 300 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.106 to 1.92 | Range of Values | 2959 | 2959 | |
. | Missing | 307 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 271 | 271 | |
1 | Below lower detection limit | 2688 | 2959 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2959 | |
. | Missing | 307 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.014 to 12.7 | Range of Values | 2896 | 2896 | |
. | Missing | 370 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 48 | 48 | |
1 | Below lower detection limit | 2848 | 2896 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2896 | |
. | Missing | 370 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.008 to 0.043 | Range of Values | 2996 | 2996 | |
. | Missing | 270 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 2 | 2 | |
1 | Below lower detection limit | 2994 | 2996 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2996 | |
. | Missing | 270 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.006 to 0.619 | Range of Values | 2905 | 2905 | |
. | Missing | 361 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 1688 | 1688 | |
1 | Below lower detection limit | 1217 | 2905 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2905 | |
. | Missing | 361 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.004 to 0.071 | Range of Values | 3014 | 3014 | |
. | Missing | 252 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 441 | 441 | |
1 | Below lower detection limit | 2573 | 3014 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 3014 | |
. | Missing | 252 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.004 to 0.018 | Range of Values | 2994 | 2994 | |
. | Missing | 272 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 21 | 21 | |
1 | Below lower detection limit | 2973 | 2994 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2994 | |
. | Missing | 272 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.028 to 115 | Range of Values | 2995 | 2995 | |
. | Missing | 271 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 1595 | 1595 | |
1 | Below lower detection limit | 1400 | 2995 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2995 | |
. | Missing | 271 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.011 | 0.011 | 2906 | 2906 | |
. | Missing | 360 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 0 | 0 | |
1 | Below lower detection limit | 2906 | 2906 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2906 | |
. | Missing | 360 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.028 to 0.564 | Range of Values | 2961 | 2961 | |
. | Missing | 305 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 8 | 8 | |
1 | Below lower detection limit | 2953 | 2961 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2961 | |
. | Missing | 305 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.354 to 0.354 | Range of Values | 2884 | 2884 | |
. | Missing | 382 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 0 | 0 | |
1 | Below lower detection limit | 2884 | 2884 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2884 | |
. | Missing | 382 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.112 to 142 | Range of Values | 2893 | 2893 | |
. | Missing | 373 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 75 | 75 | |
1 | Below lower detection limit | 2818 | 2893 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2893 | |
. | Missing | 373 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.017 to 11.2 | Range of Values | 2988 | 2988 | |
. | Missing | 278 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 1095 | 1095 | |
1 | Below lower detection limit | 1893 | 2988 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2988 | |
. | Missing | 278 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.032 to 0.505 | Range of Values | 2976 | 2976 | |
. | Missing | 290 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 7 | 7 | |
1 | Below lower detection limit | 2969 | 2976 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2976 | |
. | Missing | 290 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.018 to 0.605 | Range of Values | 3017 | 3017 | |
. | Missing | 249 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 718 | 718 | |
1 | Below lower detection limit | 2299 | 3017 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 3017 | |
. | Missing | 249 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.028 to 1.04 | Range of Values | 2938 | 2938 | |
. | Missing | 328 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 387 | 387 | |
1 | Below lower detection limit | 2551 | 2938 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2938 | |
. | Missing | 328 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.028 to 0.182 | Range of Values | 2983 | 2983 | |
. | Missing | 283 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 9 | 9 | |
1 | Below lower detection limit | 2974 | 2983 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2983 | |
. | Missing | 283 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.177 to 32.8 | Range of Values | 2953 | 2953 | |
. | Missing | 313 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 13 | 13 | |
1 | Below lower detection limit | 2940 | 2953 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2953 | |
. | Missing | 313 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.007 to 0.107 | Range of Values | 2786 | 2786 | |
. | Missing | 480 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 133 | 133 | |
1 | Below lower detection limit | 2653 | 2786 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2786 | |
. | Missing | 480 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.014 to 33.1 | Range of Values | 2835 | 2835 | |
. | Missing | 431 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 54 | 54 | |
1 | Below lower detection limit | 2781 | 2835 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2835 | |
. | Missing | 431 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.226 to 0.226 | Range of Values | 2969 | 2969 | |
. | Missing | 297 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 0 | 0 | |
1 | Below lower detection limit | 2969 | 2969 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2969 | |
. | Missing | 297 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.017 to 6.56 | Range of Values | 2994 | 2994 | |
. | Missing | 272 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 1007 | 1007 | |
1 | Below lower detection limit | 1987 | 2994 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2994 | |
. | Missing | 272 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.008 to 0.15 | Range of Values | 3017 | 3017 | |
. | Missing | 249 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 20 | 20 | |
1 | Below lower detection limit | 2997 | 3017 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 3017 | |
. | Missing | 249 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.007 to 1.09 | Range of Values | 3006 | 3006 | |
. | Missing | 260 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 22 | 22 | |
1 | Below lower detection limit | 2984 | 3006 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 3006 | |
. | Missing | 260 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.028 to 0.028 | Range of Values | 3002 | 3002 | |
. | Missing | 264 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 0 | 0 | |
1 | Below lower detection limit | 3002 | 3002 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 3002 | |
. | Missing | 264 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.088 to 1.22 | Range of Values | 2920 | 2920 | |
. | Missing | 346 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 20 | 20 | |
1 | Below lower detection limit | 2900 | 2920 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2920 | |
. | Missing | 346 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.018 to 18.1 | Range of Values | 2998 | 2998 | |
. | Missing | 268 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 2907 | 2907 | |
1 | Below lower detection limit | 91 | 2998 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2998 | |
. | Missing | 268 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.028 to 0.028 | Range of Values | 2963 | 2963 | |
. | Missing | 303 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 0 | 0 | |
1 | Below lower detection limit | 2963 | 2963 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2963 | |
. | Missing | 303 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.032 to 0.032 | Range of Values | 2993 | 2993 | |
. | Missing | 273 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 0 | 0 | |
1 | Below lower detection limit | 2993 | 2993 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 2993 | |
. | Missing | 273 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0.024 to 30.5 | Range of Values | 3013 | 3013 | |
. | Missing | 253 | 3266 |
Code or Value | Value Description | Count | Cumulative | Skip to Item |
---|---|---|---|---|
0 | At or above detection limit | 2047 | 2047 | |
1 | Below lower detection limit | 966 | 3013 | |
2 | Detectable result and exceeds the calibrated range of assay | 0 | 3013 | |
. | Missing | 253 | 3266 |