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1.
J Expo Anal Environ Epidemiol ; 11(2): 103-15, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11409003

RESUMO

Personal exposures, indoor and outdoor concentrations, and questionnaire data were collected in three retirement center settings, supporting broader particulate matter (PM)--health studies of elderly populations. The studies varied geographically and temporally, with populations studied in Baltimore, MD in the summer of 1998, and Fresno, CA in the winter and spring of 1999. The sequential nature of the studies and the relatively rapid review of the mass concentration data after each segment provided the opportunity to modify the experimental designs, including the information collected from activity diary and baseline questionnaires and influencing factors (e.g., heating, ventilation, and air-conditioning (HVAC) system operation, door and window openings, air exchange rate) measurements. This paper highlights both PM2.5 and PM10 personal exposure data and interrelationships across the three retirement center settings, and identifies the most probable influencing factors. The current limited availability of questionnaire results, and chemical speciation data beyond mass concentration for these studies, provided only limited capability to estimate personal exposures from models and apportion the personal exposure collections to their sources. The mean personal PM2.5 exposures for the elderly in three retirement centers were found to be consistently higher than the paired apartment concentrations by 50% to 68%, even though different facility types and geographic locations were represented. Mean personal-to-outdoor ratios were found to 0.70, 0.82, and 1.10, and appeared to be influenced by the time doors and windows were open and aggressive particle removal by the HVAC systems. Essentially identical computed mean PM2.5 personal clouds of 3 micrograms/m3 were determined for two of the studies. The proposed significant contributing factors to these personal clouds were resuspended particles from carpeting, collection of body dander and clothing fibers, personal proximity to open doors and windows, and elevated PM levels in nonapartment indoor microenvironments.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Exposição Ambiental , Habitação para Idosos , Aerossóis , Fatores Etários , Idoso , Monitoramento Ambiental , Humanos , Tamanho da Partícula , Estações do Ano , Temperatura , Ventilação
2.
J Air Waste Manag Assoc ; 50(11): 1887-96, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11111333

RESUMO

Two collaborative studies have been conducted by the U.S. Environmental Protection Agency (EPA) National Exposure Research Laboratory (NERL) and National Health and Environmental Effects Research Laboratory to determine personal exposures and physiological responses to particulate matter (PM) of elderly persons living in a retirement facility in Fresno, CA. Measurements of PM and other criteria air pollutants were made inside selected individual residences within the retirement facility and at a central outdoor site on the premises. In addition, personal PM exposure monitoring was conducted for a subset of the participants, and ambient PM monitoring data were available for comparison from the NERL PM research monitoring platform in central Fresno. Both a winter (February 1-28, 1999) and a spring (April 19-May 16, 1999) study were completed so that seasonal effects could be evaluated. During the spring study, a more robust personal exposure component was added, as well as a more detailed evaluation of physical factors, such as air-exchange rate, that are known to influence the penetration of particles into the indoor environment. In this paper, comparisons are made among measured personal PM exposures and PM mass concentrations measured at the NERL Fresno Platform site, outside on the premises of the retirement facility, and inside selected residential apartments at the facility during the two 28-day study periods. The arithmetic daily mean personal PM2.5 exposure during the winter study period was 13.3 micrograms/m3, compared with 9.7, 20.5, and 21.7 micrograms/m3 for daily mean overall apartment, outdoor, and ambient (i.e., platform) concentrations, respectively. The daily mean personal PM2.5 exposure during the spring study period was 11.1 micrograms/m3, compared with 8.0, 10.1, and 8.6 micrograms/m3 for the daily mean apartment, outdoor, and ambient concentrations, respectively.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar/análise , Idoso , California , Exposição Ambiental/análise , Humanos , Fatores de Tempo
3.
J Air Waste Manag Assoc ; 50(7): 1125-32, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10939206

RESUMO

In population exposure studies, personal exposure to PM is typically measured as a 12- to 24-hr integrated mass concentration. To better understand short-term variation in personal PM exposure, continuous (1-min averaging time) nephelometers were worn by 15 participants as part of two U.S. Environmental Protection Agency (EPA) longitudinal PM exposure studies conducted in Baltimore County, MD, and Fresno, CA. Participants also wore inertial impactor samplers (24-hr integrated filter samples) and recorded their daily activities in 15-min intervals. In Baltimore, the nephelometers correlated well (R2 = 0.66) with the PM2.5 impactors. Time-series plots of personal nephelometer data showed each participant's PM exposure to consist of a series of peaks of relatively short duration. Activities corresponding to a significant instrument response included cooking, outdoor activities, transportation, laundry, cleaning, shopping, gardening, moving between microenvironments, and removing/putting on the instrument. On average, 63-66% of the daily PM exposure occurred indoors at home (about 2/3 of which occurred during waking hours), primarily due to the large amount of time spent in that location (an average of 72-77%). Although not a reference method for measuring mass concentration, the nephelometer did help identify PM sources and the relative contribution of those sources to an individual's personal exposure.


Assuntos
Atividades Cotidianas , Poluição do Ar/análise , Idoso , Envelhecimento , Monitoramento Ambiental/métodos , Feminino , Humanos , Masculino , Nefelometria e Turbidimetria , Tamanho da Partícula
4.
Environ Health Perspect ; 108(6): 475-86, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10856019

RESUMO

We review the factors influencing children's exposure to environmental contaminants and the data available to characterize and assess that exposure. Children's activity pattern data requirements are demonstrated in the context of the algorithms used to estimate exposure by inhalation, dermal contact, and ingestion. Currently, data on children's exposures and activities are insufficient to adequately assess multimedia exposures to environmental contaminants. As a result, regulators use a series of default assumptions and exposure factors when conducting exposure assessments. Data to reduce uncertainty in the assumptions and exposure estimates are needed to ensure chemicals are regulated appropriately to protect children's health. To improve the database, advancement in the following general areas of research is required: identification of appropriate age/developmental benchmarks for categorizing children in exposure assessment; development and improvement of methods for monitoring children's exposures and activities; collection of activity pattern data for children (especially young children) required to assess exposure by all routes; collection of data on concentrations of environmental contaminants, biomarkers, and transfer coefficients that can be used as inputs to aggregate exposure models.


Assuntos
Proteção da Criança , Exposição Ambiental , Xenobióticos/efeitos adversos , Administração Cutânea , Administração Oral , Adolescente , Algoritmos , Biomarcadores/análise , Criança , Pré-Escolar , Bases de Dados Factuais , Humanos , Lactente , Recém-Nascido , Exposição por Inalação
5.
J Expo Anal Environ Epidemiol ; 10(6 Pt 2): 638-49, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11138656

RESUMO

In implementing the Food Quality Protection Act (FQPA) the U.S. Environmental Protection Agency (USEPA) has adopted a policy that the exposure factors and models used to assess and predict exposure to pesticides should generally be conservative. Some elements of exposure assessments for FQPA are screening level--they are both uncertain and conservative. If more realistic assessments are to be conducted, then research is required to reduce uncertainty associated with the factors and models used in the exposure assessments. To develop the strategy for conducting this research, critical exposure pathways and factors were identified, and the quality and quantity of data associated with default assumptions for exposure factors were evaluated. Then, based on our current understanding of the pathways that are potentially most important and most uncertain, significant research requirements were identified and prioritized to improve the data available and assumptions used to assess children's aggregate exposure to pesticides. Based on the results of these efforts, four priority research areas were identified: (1) pesticide use patterns in microenvironments where children spend time, (2) temporal and spatial distribution of pesticides following application in a residential setting, (3) dermal and nondietary ingestion exposure assessment methods and exposure factors, (4) dietary exposure assessment methods and exposure factors for infants and young children. The National Exposure Research Laboratory (NERL) research strategy in support of FQPA is designed to address these priority research needs.


Assuntos
Exposição Ambiental , Habitação , Modelos Teóricos , Praguicidas/efeitos adversos , Administração Cutânea , Adolescente , Criança , Proteção da Criança , Pré-Escolar , Dieta , Contaminação de Alimentos , Humanos , Lactente , Recém-Nascido , Praguicidas/análise , Medição de Risco , Fatores de Tempo
6.
J Expo Anal Environ Epidemiol ; 10(6 Pt 2): 723-31, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11138664

RESUMO

Children are the most susceptible population to lead exposure because of three interacting factors; they have more opportunity for contact with lead sources due to their activities, lead absorption occurs more readily in a child compared to an adult, and the child's development is more vulnerable to lead than adults. Low levels of lead in the blood have been shown to cause adverse health effects; the level of concern for children is currently 10 microg/dl. The contribution of dietary exposure of lead to increased blood lead levels (PbB) is not well characterized. This study was conducted to measure potential dietary lead intakes of children 2 to 3 years of age who live in homes contaminated with environmental lead. Objectives were to estimate lead intakes for children consuming food in contaminated environments, recognizing unstructured eating patterns and to investigate if correlations exist between daily dietary exposure and measured PbB. Dietary exposure was evaluated by collecting samples that were typical of the foods the young children ate in their homes. A 24-h duplicate of all foods plus sentinel foods, i.e., individual items used to represent foods contaminated during handling, were collected from 48 children. Ten homes were revisited to obtain information on the variation in daily dietary intakes. Drinking water was evaluated both as part of the segregated beverage sample composite and by itself. Additional information collected included lead concentrations from hand wipes, floor wipes, and venous blood, and questionnaire responses from the caregiver on activities potentially related to exposure. Activities and hygiene practices of the children and contamination of foods in their environment influences total dietary intake. Estimated mean dietary intakes of lead (29.2 microg Pb/day) were more than three times the measured 24-h duplicate-diet levels (8.37 microg Pb/day), which were almost six times higher than current national estimates (1.40 microg Pb/day). Statistically significant correlations were observed between floor wipes and foods contacting contaminated surfaces, hand wipes and foods contacting contaminated hands and surfaces, and hand wipes and floor wipes. This study indicates that the dietary pathway of exposure to lead is impacted by eating activities of children living in lead-contaminated environments and that analysis of foods themselves is not enough to determine excess dietary exposures that are occurring.


Assuntos
Dieta , Exposição Ambiental/análise , Contaminação de Alimentos , Chumbo/análise , Atividades Cotidianas , Proteção da Criança , Pré-Escolar , Comportamento Alimentar , Feminino , Habitação , Humanos , Higiene , Chumbo/efeitos adversos , Masculino , Abastecimento de Água
7.
J Expo Anal Environ Epidemiol ; 7(1): 17-36, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9076608

RESUMO

Dietary ingestion may be a significant pathway of human exposure to many potentially toxic chemicals. The U.S. Environmental Protection Agency-National Human Exposure Laboratory has made the development of methods for measuring personal dietary exposures a high priority for its dietary exposure research program. Of particular interest was the testing of methods that could be applied in the general population as one component of multipathway exposure measurement studies. This paper describes a controlled pilot study that was conducted to evaluate procedures for collecting and processing duplicate diet samples. Nine adult and three child participants volunteered to provide dietary information for 28 days, and duplicate portions of all foods consumed daily for seven consecutive days. Sample collection procedures were evaluated for participant collection and segregation of solid and liquid foods, and for identification and separation of high-fat and low-fat foods. Methods for compositing and homogenizing mixed diet samples were tested. Food records and questionnaires were tested to document the collected food and to evaluate procedures for assessing dietary changes and collection bias. Participant time and monetary needs were evaluated along with the approach for training and providing support to study participants. Participants were able to collect 96% of the meals they consumed, even with 33% of the meals consumed away from home. Food consumed in social settings was the most difficult to collect, and participants were unable or unwilling to collect foods in some social settings. Noncollection of meals and food items increased after the third day of collection. Mixed diet samples were successfully homogenized, with 1%-11% mean relative standard deviations for moisture, fat, protein, and ash analysis in replicate sample aliquots. The laboratory-measured caloric content of collected foods was an average of 12% (range: -24% to 36%) lower than estimates of energy intake using a food diary and 16% lower than estimated energy expenditure values.


Assuntos
Registros de Dieta , Inquéritos sobre Dietas , Análise de Alimentos/normas , Adolescente , Adulto , Pré-Escolar , Participação da Comunidade/psicologia , Participação da Comunidade/estatística & dados numéricos , Ingestão de Alimentos/psicologia , Ingestão de Energia , Métodos Epidemiológicos , Feminino , Análise de Alimentos/métodos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Reprodutibilidade dos Testes , Autoavaliação (Psicologia) , Estados Unidos
8.
J Expo Anal Environ Epidemiol ; 7(1): 61-80, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9076610

RESUMO

As part of total human exposure measurements performed on six farms in Iowa and North Carolina during the Agricultural Health Pilot Study, a household duplicate diet, several locally grown foods, an applicator meal, a child duplicate diet, and drinking water samples were collected. The pilot study was designed to test refined and newly developed protocols and analytical methods for collection and analyses of dietary samples to evaluate dietary exposure to farmers and their families in the household associated with current and former applications of pesticides. The household duplicate diet protocol was generally effective as a first step in measuring potential exposures of household members. The analytical methods used were capable of measuring 29 of the 33 targeted Agricultural Health Pilot Study pesticides in dietary samples. Collections were made during a pesticide nonapplication and application monitoring period. Pesticides in the foods and beverages of the participants were quantified at sub-ppb to 30-ppb levels in both the Iowa and North Carolina farms. Increased levels (20 ppb) of the pesticide being applied during the monitoring period were found in the applicator's meal. Dieldrin was persistent in the foods consumed on one Iowa farm. No pesticides were found in drinking water samples. The results show potential dietary exposures exceeding expected values exist to the farmers and their families for several of the pesticides in this study, particularly to those being applied and to the persistent pesticides in the environment.


Assuntos
Agricultura , Exposição Ambiental/análise , Contaminação de Alimentos/análise , Saúde Ocupacional , Resíduos de Praguicidas/isolamento & purificação , Adulto , Criança , Registros de Dieta , Monitoramento Ambiental , Saúde da Família , Humanos , Iowa , Estudos Longitudinais , Concentração Máxima Permitida , North Carolina , Exposição Ocupacional/análise , Projetos Piloto , Valores de Referência , Abastecimento de Água/análise
9.
J Expo Anal Environ Epidemiol ; 7(1): 37-59, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9076609

RESUMO

Dietary uptake may be a significant pathway of exposure to contaminants. As such, dietary exposure assessments should be considered an important part of the total exposure assessment process. The objective of this work was to develop reliable methods that are applicable to a wide range of base/neutral and carbamate-type pesticides in duplicate diet samples collected as part of dietary exposure assessment studies. The resulting method needed to be sensitive to concentrations below 1 ng/g, accurate and precise, and as simple and cost effective as possible. As a first step, information was gathered on current methods for measuring pesticides in foods. Although the literature methods could serve as a starting point, few had been applied to duplicate diet samples and detection limits were generally high (10 to 100 ng/g). Experimental work was performed to evaluate individual extraction, cleanup, and analysis procedures; link the most promising procedures into analysis methods; and generate performance data on the final method. The final method used Soxhlet extraction with solvent partitioning and gel permeation chromatography cleanup. Gas chromatography/mass spectrometry was used for the analysis of base/neutral pesticides. High performance liquid chromatography analysis was used for the analysis of carbamate pesticides. Results of performance testing showed good accuracy (recovery > 70%), precision (% RSD < 25%), and sensitivity (method detection limits < 1.0 ng/g) for most pesticides targeted for study.


Assuntos
Exposição Ambiental/análise , Análise de Alimentos/normas , Contaminação de Alimentos/análise , Resíduos de Praguicidas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Registros de Dieta , Métodos Epidemiológicos , Análise de Alimentos/métodos , Análise de Alimentos/estatística & dados numéricos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Resíduos de Praguicidas/química , Reprodutibilidade dos Testes , Fatores de Tempo
11.
Health Phys ; 58(2): 147-55, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2298570

RESUMO

Results are presented from a statewide survey that measured annual 222Rn concentrations in over 2000 single-family, owner-occupied homes in New York state. The participants were selected by a random-digit-dialing telephone interview approach developed by Mitofsky-Waksberg which allows inferences to be made from the sample to the statewide population. After completing a telephone questionnaire and agreeing to have their homes monitored, eligible households were mailed alpha-track detectors with instructions to place one detector in the main living area for 2 mo (during the winter heating season), a second in the main living area for 1 y, and a third in the basement (if applicable) for 1 y. The statewide median concentration for the heating-season, living-area readings was 31.6 Bq m-3, with a median of 24.0 Bq m-3 for the annual living-area readings and 51.8 for the annual basement readings. For the state, approximately 95% of the living-area concentrations and 86% of the basement concentrations were below 148 Bq m-3 (4 pCi L-1). In addition, only 1.4% of the readings in the basement were above 740 Bq m-3 (20 pCi L-1).


Assuntos
Habitação , Poluentes Radioativos/análise , Radônio/análise , Calefação , New York , Monitoramento de Radiação/métodos , Distribuição Aleatória
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