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Understanding the complex interplay of genetic and environmental factors in disease etiology and the role of gene-environment interactions (GEIs) across human development stages is important. We review the state of GEI research, including challenges in measuring environmental factors and advantages of GEI analysis in understanding disease mechanisms. We discuss the evolution of GEI studies from candidate gene-environment studies to genome-wide interaction studies (GWISs) and the role of multi-omics in mediating GEI effects. We review advancements in GEI analysis methods and the importance of large-scale datasets. We also address the translation of GEI findings into precision environmental health (PEH), showcasing real-world applications in healthcare and disease prevention. Additionally, we highlight societal considerations in GEI research, including environmental justice, the return of results to participants, and data privacy. Overall, we underscore the significance of GEI for disease prediction and prevention and advocate for integrating the exposome into PEH omics studies.
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Saúde Ambiental , Interação Gene-Ambiente , Medicina de Precisão , Humanos , Medicina de Precisão/métodos , Estudo de Associação Genômica Ampla , Exposição Ambiental/efeitos adversosRESUMO
OBJECTIVE: To examine the frequency of, and risk factors for, disease flare following COVID-19 vaccination in patients with systemic rheumatic disease (SRD). METHODS: An international study was conducted from 2 April to 16 August 2021, using an online survey of 5619 adults with SRD for adverse events following COVID-19 vaccination, including flares of disease requiring a change in treatment. We examined risk factors identified a priori based on published associations with SRD activity and SARS-CoV-2 severity, including demographics, SRD type, comorbidities, vaccine type, cessation of immunosuppressive medications around vaccination and history of reactions to non-COVID-19 vaccines, using multivariable logistic regression. RESULTS: Flares requiring a change in treatment following COVID-19 vaccination were reported by 4.9% of patients. Compared with rheumatoid arthritis, certain SRD, including systemic lupus erythematosus (OR 1.51, 95% CI 1.03, 2.20), psoriatic arthritis (OR 1.95, 95% CI 1.20, 3.18) and polymyalgia rheumatica (OR 1.94, 95% CI 1.08, 2.48) were associated with higher odds of flare, while idiopathic inflammatory myopathies were associated with lower odds for flare (OR 0.54, 95% CI 0.31-0.96). The Oxford-AstraZeneca vaccine was associated with higher odds of flare relative to the Pfizer-BioNTech vaccine (OR 1.44, 95% CI 1.07, 1.95), as were a prior reaction to a non-COVID-19 vaccine (OR 2.50, 95% CI 1.76, 3.54) and female sex (OR 2.71, 95% CI 1.55, 4.72). CONCLUSION: SRD flares requiring changes in treatment following COVID-19 vaccination were uncommon in this large international study. Several potential risk factors, as well as differences by disease type, warrant further examination in prospective cohorts.
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Vacinas contra COVID-19 , COVID-19 , Doenças Reumáticas , Adulto , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/classificação , Feminino , Humanos , Masculino , Estudos Prospectivos , Doenças Reumáticas/complicações , Autorrelato , Exacerbação dos Sintomas , Vacinação/efeitos adversosRESUMO
Importance: Exposure to hydrocarbons, fine particulate matter (PM2.5), and other chemicals from the April 20, 2010, Deepwater Horizon disaster may be associated with increased blood pressure and newly detected hypertension among oil spill response and cleanup workers. Objective: To determine whether participation in cleanup activities following the disaster was associated with increased risk of developing hypertension. Design, Setting, and Participants: This cohort study was conducted via telephone interviews and in-person home exams. Participants were 6846 adults who had worked on the oil spill cleanup (workers) and 1505 others who had completed required safety training but did not do cleanup work (nonworkers). Eligible participants did not have diagnosed hypertension at the time of the oil spill. Statistical analyses were performed from June 2018 to December 2021. Exposures: Engagement in cleanup activities following the Deepwater Horizon oil spill disaster, job classes, quintiles of cumulative total hydrocarbons exposure level, potential exposure to burning or flaring oil, and estimated PM2.5 were examined. Main Outcomes and Measures: Systolic and diastolic blood pressure measurements were collected during home exams from 2011 to 2013 using automated oscillometric monitors. Newly detected hypertension was defined as antihypertensive medication use or elevated blood pressure since the spill. Log binomial regression was used to calculate prevalence ratios (PR) and 95% CIs for associations between cleanup exposures and hypertension. Multivariable linear regression was used to estimate exposure effects on continuous blood pressure levels. Results: Of 8351 participants included in this study, 6484 (77.6%) were male, 517 (6.2%) were Hispanic, 2859 (34.2%) were non-Hispanic Black, and 4418 (52.9%) were non-Hispanic White; the mean (SD) age was 41.9 (12.5) years at enrollment. Among workers, the prevalence of newly detected hypertension was elevated in all quintiles (Q) of cumulative total hydrocarbons above the first quintile (PR for Q3, 1.29 [95% CI, 1.13-1.46], PR for Q4, 1.25 [95% CI, 1.10-1.43], and PR for Q5, 1.31 [95% CI, 1.15-1.50]). Both exposure to burning and/or flaring oil and gas (PR, 1.16 [95% CI, 1.02-1.33]) and PM2.5 from burning (PR, 1.26 [95% CI, 0.89-1.71]) for the highest exposure category were associated with increased risk of newly detected hypertension, as were several types of oil spill work including cleanup on water (PR, 1.34 [95% CI, 1.08-1.66]) and response work (PR, 1.51 [95% CI, 1.20-1.90]). Conclusions and Relevance: Oil spill exposures were associated with newly detected hypertension after the Deepwater Horizon disaster. These findings suggest that blood pressure screening should be considered for workers with occupational hydrocarbon exposures.
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Desastres , Hipertensão/epidemiologia , Exposição Ocupacional/estatística & dados numéricos , Poluição por Petróleo/estatística & dados numéricos , Adulto , Pressão Sanguínea/fisiologia , Estudos de Coortes , Recuperação e Remediação Ambiental , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
INTRODUCTION: The 2010 Deepwater Horizon (DWH) disaster exposed tens of thousands of oil spill response and cleanup (OSRC) workers to hydrocarbons and other hazardous chemicals. Some hydrocarbons, such as toluene and hexane, have been found to have acute adverse effects on the central nervous system in occupational settings. However, no studies have examined the association between oil spill exposures and neurobehavioral function. METHODS: We used data from the Gulf Long-term Follow-up Study, a cohort of adults who worked on the DWH response and cleanup. Total hydrocarbon (THC) exposure attributed to oil spill cleanup work was estimated from a job-exposure matrix linking air measurement data to detailed cleanup work histories. Participants were also categorized into 6 job categories, or OSRC classes, based on their activity with the highest exposure. Neurobehavioral performance was assessed at a clinical exam 4-6 years after the spill. We used multivariable linear regression to evaluate relationships of ordinal THC levels and OSRC classes with 16 neurobehavioral outcomes. RESULTS: We found limited evidence of associations between THC levels or OSRC classes and decreased neurobehavioral function, including attention, memory, and executive function. Workers exposed to ≥3â¯ppm THC scored significantly worse (difference1.0-2.9ppmâ¯=â¯-0.39, 95% confidence interval (CI)â¯=â¯-0.74, -0.04) than workers exposed to <0.30â¯ppm THC for the digit span forward count test. There was also a possible threshold effect above 1â¯ppm THC for symbol digit test total errors (difference1.0-2.9ppmâ¯=â¯-0.56 (95% CIâ¯=â¯-1.13, -0.003), difference≥3.0ppmâ¯=â¯-0.55 (95% CIâ¯=â¯-1.20, 0.10)). Associations appeared to be stronger in men than in women. A summary latency measure suggested an association between more highly exposed jobs (especially support of operations workers) and decreased neurobehavioral function. CONCLUSION: OSRC-related exposures were associated with modest decreases in neurobehavioral function, especially attention, memory, and executive function.
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Doenças do Sistema Nervoso/epidemiologia , Exposição Ocupacional/estatística & dados numéricos , Poluição por Petróleo/estatística & dados numéricos , Adulto , Desastres , Feminino , Seguimentos , Golfo do México , Humanos , Hidrocarbonetos , MasculinoRESUMO
Research conducted in the wake of a disaster can provide information to help mitigate health consequences, support future recovery efforts, and improve resilience. However, a number of barriers have prevented time-sensitive research responses following previous disasters. Furthermore, large-scale disasters present their own special challenges due to the number of people exposed to disaster conditions, the number of groups engaged in disaster response, and the logistical challenges of rapidly planning and implementing a large study. In this case study, we illustrate the challenges in planning and conducting a large-scale post-disaster research study by drawing on our experience in establishing the Gulf Long-term Follow-up (GuLF) Study following the 2010 Deepwater Horizon disaster. We describe considerations in identifying at-risk populations and appropriate comparison groups, garnering support for the study from different stakeholders, obtaining timely scientific and ethics review, measuring and characterizing complex exposures, and addressing evolving community health concerns and unmet medical needs. We also describe the NIH Disaster Research Response (DR2) Program, which provides a suite of resources, including data collection tools, research protocols, institutional review board guidance, and training materials to enable the development and implementation of time-critical studies following disasters and public health emergencies. In describing our experiences related to the GuLF Study and the ongoing efforts through the NIH DR2 Program, we aim to help improve the timeliness, quality, and value of future disaster-related data collection and research studies.
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Planejamento em Desastres/organização & administração , Desastres/prevenção & controle , Recuperação e Remediação Ambiental/estatística & dados numéricos , Poluição por Petróleo/estatística & dados numéricos , Humanos , Estudos de Casos Organizacionais , Saúde PúblicaRESUMO
BACKGROUND: Workers involved in the response and clean-up of the 2010 Deepwater Horizon oil spill faced possible exposures to crude oil, burning oil, dispersants and other pollutants in addition to physical and emotional stress. These exposures may have increased risk of myocardial infarction (MI) among oil spill workers. METHODS: Gulf Long-term Follow-up (GuLF) STUDY participants comprise individuals who either participated in the Deepwater Horizon response efforts or registered for safety training but were not hired. Oil spill-related exposures were assessed during enrollment interviews conducted in 2011-2013. We estimated risk ratios (RR) and 95% confidence intervals for the associations of clean-up work characteristics with self-reported nonfatal MI up to three years post-spill. RESULTS: Among 31,109 participants without history of MI prior to the spill, 77% worked on the oil spill. There were 192 self-reported MI during the study period; 151 among workers. Among the full cohort, working on the oil spill clean-up (vs not working on the clean-up) and living in proximity to the oil spill (vs further away) were suggestively associated with a possible increased risk of nonfatal MI [RR: 1.22 (0.86, 1.73) and 1.15 (0.82, 1.60), respectively]. Among oil spill workers, working for > 180 days was associated with MI [RR for > 180 days (vs 1-30 days): 2.05 (1.05, 4.01)], as was stopping working due to heat [RR: 1.99 (1.43, 2.78)]. There were suggestive associations of maximum total hydrocarbon exposure ≥3.00 ppm (vs < 0.30 ppm) [RR: 1.69 (0.90, 3.19)] and working on decontaminating oiled equipment (vs administrative support) [1.72 (0.96, 3.09)] with nonfatal MI. CONCLUSION: This is the first study to assess the associations between oil spill exposures and MI. Results suggest that working on the spill for > 180 days and stopping work due to heat increased risk of nonfatal MI. Future research should evaluate whether the observed associations are related to specific chemical exposures or other stressors associated with the spill.
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Infarto do Miocárdio/epidemiologia , Exposição Ocupacional/efeitos adversos , Poluição por Petróleo/efeitos adversos , Petróleo/efeitos adversos , Poluentes Químicos da Água/efeitos adversos , Adulto , Idoso , Estudos de Coortes , Feminino , Golfo do México , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/induzido quimicamente , Estudos Prospectivos , Autorrelato , Sudeste dos Estados Unidos/epidemiologia , Adulto JovemRESUMO
OBJECTIVE: The aim of this study was to assess the relationship between total hydrocarbon (THC) exposures attributed to oil spill clean-up work and lung function 1 to 3 years after the Deepwater Horizon (DWH) disaster. METHODS: We used data from the GuLF STUDY, a large cohort of adults who worked on response to the DWH disaster and others who were safety trained but did not work. We analyzed data from 6288 workers with two acceptable spirometry tests. We estimated THC exposure levels with a job exposure matrix. We evaluated lung function using the forced expiratory volume in 1âsecond (FEV1; mL), the forced vital capacity (FVC; mL), and the FEV1/FVC ratio (%). RESULTS: Lung function measures did not differ by THC exposure levels among clean-up workers. CONCLUSION: We did not observe an association between THC exposure and lung function among clean-up workers 1 to 3 years following the DWH disaster.
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Poluentes Ocupacionais do Ar/toxicidade , Hidrocarbonetos/toxicidade , Exposição Ocupacional/efeitos adversos , Indústria de Petróleo e Gás , Adulto , Recuperação e Remediação Ambiental , Feminino , Seguimentos , Volume Expiratório Forçado , Golfo do México , Humanos , Masculino , Pessoa de Meia-Idade , Poluição por Petróleo , Estudos Prospectivos , Espirometria , Capacidade VitalRESUMO
BACKGROUND: Little is known about the effects of inhalation exposures on lung function among workers involved in the mitigation of oil spills. Our objective was to determine the relationship between oil spill response work and lung function 1-3 years after the Deepwater Horizon (DWH) disaster. METHODS: We evaluated spirometry for 7,775 adults living in the Gulf states who either participated in DWH response efforts (workers) or received safety training but were not hired (nonworkers). At an enrollment interview, we collected detailed work histories including information on potential exposure to dispersants and burning oil/gas. We assessed forced expiratory volume in 1 second (FEV1; mL), forced vital capacity (FVC; mL), and the ratio (FEV1/FVC%) for differences by broad job classes and exposure to dispersants or burning oil/gas using multivariable linear and modified Poisson regression. RESULTS: We found no differences between workers and nonworkers. Among workers, we observed a small decrement in FEV1 (Beta, -71 mL; 95% confidence interval [CI], -127 to -14) in decontamination workers compared with support workers. Workers with high potential exposure to burning oil/gas had reduced lung function compared with unexposed workers: FEV1 (Beta, -183 mL; 95% CI, -316 to -49) and FEV1/FVC (Beta, -1.93%; 95% CI, -3.50 to -0.36), and an elevated risk of having a FEV1/FVC in the lowest tertile (prevalence ratio, 1.38; 95% CI, 0.99 to 1.92). CONCLUSIONS: While no differences in lung function were found between workers and nonworkers, lung function was reduced among decontamination workers and workers with high exposure to burning oil/gas compared with unexposed workers.
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Desastres , Exposição por Inalação/análise , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/fisiopatologia , Indústria de Petróleo e Gás , Poluição por Petróleo , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sudeste dos Estados Unidos , EspirometriaRESUMO
To address concerns among Gulf Coast residents about ongoing exposures to volatile organic compounds, including benzene, toluene, ethylbenzene, o-xylene, and m-xylene/p-xylene (BTEX), we characterized current blood levels and identified predictors of BTEX among Gulf state residents. We collected questionnaire data on recent exposures and measured blood BTEX levels in a convenience sample of 718 Gulf residents. Because BTEX is rapidly cleared from the body, blood levels represent recent exposures in the past 24 h. We compared participants' levels of blood BTEX to a nationally representative sample. Among nonsmokers we assessed predictors of blood BTEX levels using linear regression, and predicted the risk of elevated BTEX levels using modified Poisson regression. Blood BTEX levels in Gulf residents were similar to national levels. Among nonsmokers, sex and reporting recent smoky/chemical odors predicted blood BTEX. The change in log benzene was -0.26 (95% CI: -0.47, -0.04) and 0.72 (0.02, 1.42) for women and those who reported odors, respectively. Season, time spent away from home, and self-reported residential proximity to Superfund sites (within a half mile) were statistically associated with benzene only, however mean concentration was nearly an order of magnitude below that of cigarette smokers. Among these Gulf residents, smoking was the primary contributor to blood BTEX levels, but other factors were also relevant.
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Hidrocarbonetos Aromáticos/sangue , Fumar/sangue , Compostos Orgânicos Voláteis/sangue , Adulto , Benzeno , Monitoramento Ambiental/métodos , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estações do Ano , Sudeste dos Estados Unidos , Inquéritos e Questionários , Tolueno , Adulto JovemRESUMO
BACKGROUND: The 2010 Deepwater Horizon disaster led to the largest ever marine oil spill. Individuals who worked on the spill were exposed to toxicants and stressors that could lead to adverse effects. OBJECTIVES: The GuLF STUDY was designed to investigate relationships between oil spill exposures and multiple potential physical and mental health effects. METHODS: Participants were recruited by telephone from lists of individuals who worked on the oil spill response and clean-up or received safety training. Enrollment interviews between 2011 and 2013 collected information about spill-related activities, demographics, lifestyle, and health. Exposure measurements taken during the oil spill were used with questionnaire responses to characterize oil exposures of participants. Participants from Gulf states completed a home visit in which biological and environmental samples, anthropometric and clinical measurements, and additional health and lifestyle information were collected. Participants are being followed for changes in health status. RESULTS: Thirty-two thousand six hundred eight individuals enrolled in the cohort, and 11,193 completed a home visit. Most were young (56.2% ≤ 45 years of age), male (80.8%), lived in a Gulf state (82.3%), and worked at least 1 day on the oil spill (76.5%). Workers were involved in response (18.0%), support operations (17.5%), clean-up on water (17.4%) or land (14.6%), decontamination (14.3%), and administrative support (18.3%). Using an ordinal job exposure matrix, 45% had maximum daily total hydrocarbon exposure levels ≥ 1.0 ppm. CONCLUSIONS: The GuLF STUDY provides a unique opportunity to study potential adverse health effects from the Deepwater Horizon oil spill.
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Desastres , Exposição Ocupacional/estatística & dados numéricos , Poluição por Petróleo/estatística & dados numéricos , Golfo do México , Humanos , Estudos ProspectivosRESUMO
The 2010 Deepwater Horizon (DWH) explosion in the Gulf of Mexico led to the largest ever marine oil spill by volume. The GuLF STUDY is investigating possible adverse human health effects associated with oil spill activities. One objective of the study was to utilize biological specimens from study participants to examine spill-related adverse health effects. This study describes the methods for collecting, processing, shipping, and storing specimens during the enrollment phase of the study. GuLF STUDY participants living in Gulf States (Alabama, Florida, Louisiana, Mississippi, and eastern Texas) were eligible to complete a home visit at enrollment, one to three years after the DWH explosion. During this visit, blood, urine, toenail and hair clippings, and house dust samples were collected. Specimens were shipped overnight to a central processing laboratory in containers with cold and ambient temperature compartments. Most blood and urine specimens were then aliquoted and stored in liquid nitrogen vapor or at -80°C, with some samples stored at -20°C. A total of 11,193 participants completed a home visit, and over 99% provided at least one biospecimen. Most participants provided blood (93%), urine (99%), and toenail clippings (89%), and 40% provided hair. Nearly all participants (95%) provided house-dust samples. Most samples were received by the laboratory one (58%) or two (25%) days after collection. These biospecimens enable investigation of a range of biomarkers of spill-related adverse health effects, and possibly some biomarkers of spill-related exposures. The biospecimen collection, handling, and storage protocols were designed to maximize current and future scientific value within logistical and budgetary constraints and might serve as a template for future studies conducted in similar time-critical and geographically dispersed settings.
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Exposição Ocupacional , Poluição por Petróleo/efeitos adversos , Manejo de Espécimes/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Monitoramento Ambiental , Feminino , Seguimentos , Golfo do México , Humanos , Masculino , Pessoa de Meia-Idade , Sudeste dos Estados Unidos , Texas , Adulto JovemRESUMO
BACKGROUND: Although asphalt fume is a recognized irritant, previous studies of acute symptoms during asphalt paving have produced inconsistent results. Between 1994 and 1997, the National Institute for Occupational Safety and Health (NIOSH) evaluated workers at seven sites in six states. METHODS: NIOSH (a) measured exposures of asphalt paving workers to total (TP) and benzene-soluble particulate (BSP), polycyclic aromatic compounds, and other substances; (b) administered symptom questionnaires pre-shift, every 2 hr during the shift, and post-shift to asphalt exposed and nonexposed workers; and (c) measured peak expiratory flow rate (PEFR) of asphalt paving workers when they completed a symptom questionnaire. RESULTS: Full-shift time-weighted average exposures to TP and BSP ranged from 0.01 to 1.30 mg/m(3) and 0.01 to 0.82 mg/m(3), respectively. Most BSP concentrations were <0.50 mg/m(3). Asphalt workers had a higher occurrence rate of throat irritation than nonexposed workers [13% vs. 4%, odds ratio (OR) = 4.0, 95% confidence interval (CI): 1.2-13]. TP, as a continuous variable, was associated with eye (OR = 1.34, 95% CI: 1.12-1.60) and throat (OR = 1.40, 95% CI: 1.06-1.85) symptoms. With TP dichotomous at 0.5 mg/m(3), the ORs and 95% CIs for eye and throat symptoms were 7.5 (1.1-50) and 15 (2.3-103), respectively. BSP, dichotomous at 0.3 mg/m(3), was associated with irritant (eye, nose, or throat) symptoms (OR = 11, 95% CI: 1.5-84). One worker, a smoker, had PEFR-defined bronchial lability, which did not coincide with respiratory symptoms. CONCLUSIONS: Irritant symptoms were associated with TP and BSP concentrations at or below 0.5 mg/m(3).
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Poluentes Ocupacionais do Ar/análise , Oftalmopatias/epidemiologia , Hidrocarbonetos , Exposição por Inalação/análise , Exposição Ocupacional/análise , Doenças Respiratórias/epidemiologia , Doença Aguda , Análise de Variância , Monitoramento Ambiental , Monitoramento Epidemiológico , Oftalmopatias/etiologia , Feminino , Humanos , Modelos Logísticos , Masculino , National Institute for Occupational Safety and Health, U.S. , Tamanho da Partícula , Testes de Função Respiratória , Doenças Respiratórias/etiologia , Estados Unidos/epidemiologiaRESUMO
CONTEXT: Bioterrorist attacks involving letters and mail-handling systems in Washington, DC, resulted in Bacillus anthracis (anthrax) spore contamination in the Hart Senate Office Building and other facilities in the US Capitol's vicinity. OBJECTIVE: To provide information about the nature and extent of indoor secondary aerosolization of B anthracis spores. DESIGN: Stationary and personal air samples, surface dust, and swab samples were collected under semiquiescent (minimal activities) and then simulated active office conditions to estimate secondary aerosolization of B anthracis spores. Nominal size characteristics, airborne concentrations, and surface contamination of B anthracis particles (colony-forming units) were evaluated. RESULTS: Viable B anthracis spores reaerosolized under semiquiescent conditions, with a marked increase in reaerosolization during simulated active office conditions. Increases were observed for B anthracis collected on open sheep blood agar plates (P<.001) and personal air monitors (P =.01) during active office conditions. More than 80% of the B anthracis particles collected on stationary monitors were within an alveolar respirable size range of 0.95 to 3.5 micro m. CONCLUSIONS: Bacillus anthracis spores used in a recent terrorist incident reaerosolized under common office activities. These findings have important implications for appropriate respiratory protection, remediation, and reoccupancy of contaminated office environments.
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Aerossóis , Poluição do Ar em Ambientes Fechados , Bacillus anthracis , Bioterrorismo , Monitoramento Ambiental , Esporos Bacterianos , Local de Trabalho , District of Columbia , Microbiologia Ambiental , Governo Federal , Humanos , United States Government AgenciesRESUMO
BACKGROUND: Nosocomial transmission of Mycobacterium tuberculosis among workers at a 1000-bed inner-city hospital led to an extensive evaluation of this risk among workers with potential exposure to TB patients or laboratory specimens. METHODS: Retrospective cohort study to determine the incidence and risk of tuberculin skin test (TST) conversions among workers employed 1/1/90 to 9/30/92. RESULTS: Personal, community, and occupational risk factors were evaluated in 2,362 workers with potential M. tuberculosis exposure and 886 workers with no known exposure. The 33-month cumulative rate of TST conversion was 5.8% for potentially exposed workers and 2.0% for controls (RR 3.6; 95% CI; 2.2-5.8). Among workers with potential M. tuberculosis exposure, statistically significantly elevated risks were found for nurses, laboratory technicians, pharmacy workers, phlebotomists, housekeepers, clerks, emergency room workers, and emergency responders. CONCLUSIONS: Workers with patient contact and those employed in certain occupational groups were at increased risk for occupational M. tuberculosis infection.