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The National Human Exposure Assessment Survey study in Arizona (AZ NHEXAS) sampled trace metals in multimedia in and outside of 176 representative homes in Arizona. PM10 was collected using low-flow impactors indoors and out. Primary metals evaluated from monitoring of indoor and outdoor air were lead, cadmium, chromium, nickel, and arsenic. Secondary metals were also evaluated. They were analyzed using gas chromatography-inductively coupled plasma/atomic emission spectroscopy (GC-ICP/AES). Air concentrations of metals do not contribute appreciable amounts to total concentrations of metals, and none were above levels of concern. Measurements were made of selected pesticides (primarily chlorpyrifos and diazinon) from particulate matter (PM10) filters obtained indoors and outdoors. Indoor air pesticide exposures represent about 254570360f the total exposure to these pesticides. The highest 1060305370f exposures were related to questions about pesticide usage, at home and at work. [ABSTRACT FROM AUTHOR]

The objective of the National Human Exposure Assessment Survey (NHEXAS) in Arizona is to determine the multimedia distribution of total human exposure to environmental pollutants in the classes of metals, pesticides, and volatile organic compounds (VOCs) for the population of Arizona. This was accomplished by studying a probability-based sample of the total population in Arizona with a nested design for the different stages of sampling (954 Stage I, 505 Stage II, and 179 Stage III participants). This report compares the study population demographics with those from the U.S. Census and provides preliminary data on the distributions of the example pollutant for each class, lead for metals, chlorpyrifos for pesticides, and benzene for metals. The probability-based sample age and gender demographics compare reasonably well with the Census data (1990 Census and 1996 Census Estimate). The race/ethnicity compared less well with 21% Hispanics in the 1996 Census Estimate and 42% Hispanics in the entire NHEXAS-Arizona sample and 30% Hispanics as Stage III participants for this study. The chemical analyses of the various media (yard soil, foundation soil, house dust, indoor air, outdoor air, drinking water, food, and beverage) show generally low levels of the representative pollutants. The 50th percentiles of the distributions are generally near or below the analytical detection limits, and applicable Federal action limits were rarely exceeded.

Data entry and management are critical components of all large survey projects; data quality objectives must be met and data must be quickly and readily accessible. We developed a comprehensive system for data entry and management utilizing scannable forms with bubble fields and handwriting recognition. This 'Mass Data Massage' (MDM) system had three components: (1) form creation and database definition; (2) programming of data dictionaries for documentation and preliminary logic and range checks; and (3) data entry, management and documentation using the 'Mass Data Cleaning Program' (MDCP). Scannable forms were written in Teleform, where the data field definition, variable names and ranges were defined as the form was created. Completed forms were returned from the field, subjected to final field quality control (QC) checks, and transferred to the data management section. They were batched and coded as necessary. Once a batch of data was scanned and visually verified, the operator called up the menu for the MDCP. The MDCP had 31 program modules with 500-1200 lines of code each. The operator could select and run the appropriate dictionary on each data batch 'correcting' apparent errors in responses. This process was iterative until the data batch passed all dictionary checks. Proposed 'changes' were forwarded to the data coordinator (DC) for acceptance or rejection. After all errors had been resolved, each data batch was subjected to a 10% quality assurance (QA) check. The original data batch and associated file of applied changes were archived. Time expenditure using the scanning approach varied with the number of questions and the types of responses (handwritten or bubble fields). One-page forms took 42-60% of the time needed for hand entry; forms longer than 10 pages took 35-38% of the time. Use of faster machines will further speed the process. The main advantage of the system was the reduction of systematic errors. Scanning alone reduced errors found on 995 NHEXAS Baseline Questionnaires. Overall, the dictionary identified 0.55% errors on the scanned forms. Ten percent QC checks, performed on corrected batches ready for appendage to the master database, revealed an overall error rate of 0.02%. Similar checks on a laboratory form scanned from numeric handwriting detected 0.3% errors following dictionary application and 0.2% errors during the 10% QA check. This system was faster, more accurate, and more cost-effective than hand entry of data. A batch of data that took >1 week to process using the hand entry method was processed within 1 day using MDM. Human coding of specific answers and the final verification were the most time-consuming processes.

NHEXAS AZ is a multimedia, multipathway exposure assessment survey designed to evaluate metals and other analytes. This paper reports the analyte-specific concentration distributions in each of the media examined (air, soil, house dust, food, beverage, and water), for various methodologies used (inductively coupled plasma-atomic emission spectroscopy and hydride generation-atomic absorption spectroscopy). Results are reported for the five primary metals (Pb, As, Cd, Cr, and Ni). Ingestion was the most important pathway of exposure. Metal concentrations in air were very low (ng/m3) and found only above the 90th percentile. Metals were commonly found in house dust and soil. Exposure transfer coefficients minimize the importance of this component for those over the age of 6 years. When ranked by exposure, food, beverage, and water appeared to be the primary contributors of metal exposure in NHEXAS AZ. For instance, at the 90th percentile, Pb was undetected in air, found at 131 and 118 microg/m3 in floor dust and soil, respectively, and measured at 16 microg/kg in food, 7.1 microg/kg in beverage, and 2.0 and 1.3 microg/l in drinking and tap water, respectively. We calculated preliminary estimates of total exposure (microg/day) for each participant and examined them independently by age, gender, and ethnicity as reported by the subjects in the NHEXAS questionnaire. At the 90th percentile for Pb, total exposures were 64 microg/day across all subjects (n=176); adult men (n=55) had the greatest exposure (73 microg/day) and children (n=35) the least (37 microg/day). Hispanics (n=54) had greater exposure to Pb (68 microg/day) than non-Hispanics (n=119; 50 microg/day), whereas non-Hispanics had greater exposure for all other metals reported. These results have implications related to environmental justice. The NHEXAS project provides information to make informed decisions for protecting and promoting appropriate public health policy.

Diurnal variability in peak expiratory flow (PEF) has been an accepted clinical method in the management of asthma and the evaluation of occupational asthma. In this paper, the basis for this usage together with other clinical and epidemiological applications is discussed. The measured characteristics of PEF diurnal variability are described in asthmatics and asymptomatic subjects, showing the greater variability in asthmatics, and the "morning dip" related to circadian rhythm. PEF measured by pneumotachograph and the mini-Wright meter are shown to be in good agreement, but PEF measured by the latter and other small PEF meters is different in terms of absolute values, and both intraindividual variability within test sets and diurnally. The use of PEF meters, and the daily diaries in which the subject or patient records PEF and related factors are described.

The objective of this proposed Phase I field study is to determine the distributions of total human exposures to multimedia pollutants in the classes of metals, pesticides, and volatile organic compounds (VOCs). This will be achieved by studying a proportion-based sample of the total population in Arizona with a nested design for the different stages of sampling. Specific objectives are: (1) to document the occurrence, distribution, and determinants of total exposures in the general population; (2) to characterize the 90th percentiles of total exposures to each pollutant; (3) to monitor geographic and temporal trends of the multimedia exposures; (4) to evaluate the different media, personal, time-activity, and geographical factors that contribute to current total exposure; (5) to evaluate biomarkers in blood and urine for the target pollutants; (6) to perform evaluations of relationships between exposure reports, environmental measurements, and biomarkers of the target pollutants; (7) to predict total exposures; and (8) to assess total exposures in minority and disadvantaged subsets of the population. The latter is particularly feasible in Arizona due to the large proportions of such population subgroups. The proportionate-based population sampling of households within blocks will occur in Stage 1; the target is 1,200 such households. They will be interviewed utilizing National Human Exposure Assessment Survey (NHEXAS) questionnaires. In Stage 2, additional questionnaires will be completed; environmental sampling will take place in 450-900 households representatively selected from the respondents. Environmental sampling will include: metals in dust, soil, outside air, and some tap water; pesticides in dust, soil, and some tap water; total VOCs in air. In Stage 3, a subset of representative households will be reevaluated for metals, pesticides, and VOCs using methods with greater resolution and reliability; subjects in these households will be asked to complete questionnaires and provide biological samples. Follow-up temporal evaluations will be performed in a randomly selected subset of homes evaluated during this stage.

Relationships between respiratory health and environmental conditions (pollen, pollution and meteorology) are investigated in 204 subjects in four symptom groups in four geographical clusters in Tucson. Techniques used are principal components, factor and path analysis. Daily respiratory symptoms and peak expiratory flows were recorded during a three-year period. Ambient pollutants, meteorological conditions and pollen types were monitored in or near the clusters. Factor-based scales, which are climate and season specific, are developed for the environmental variables. Three pollutant/meteorological scales represent 'Summer', 'Winter', and 'Humidity'. Four pollen scales represent early and late spring, summer and fall pollen types. Relationships between environmental variables, respiratory symptoms and peak expiratory flow are analyzed with path diagrams, after accounting for age, sex, smoking habits and stove type. The different effects of the environment on asthmatics, allergics and airways obstructive disease subjects have been demonstrated. Many relationships were found between environmental factors and respiratory responses. The pollutant and meteorological variables are related to respiratory symptoms and peak flow directly as well as through interactions with pollen types. Some of the largest positive coefficients are seen in association with seasonal pollen types, specifically, rhinitis and dyspnoea.