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1.
Inhal Toxicol ; 27(5): 262-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25942054

RESUMO

CONTEXT: We had available records on over 300 workers evaluated with the beryllium bronchoalveolar lavage lymphocyte proliferation test (BeBALLPT) at three expert chronic beryllium disease (CBD) diagnostic centers. OBJECTIVE: The objective was to describe the contribution of the BeBALLPT to classification of workers with respect to beryllium sensitization (BeS) and beryllium-induced lung inflammation. METHODS: Company records were used to identify beryllium workers who had undergone diagnostic bronchoscopy with BeBALLPT. Clinical, work and smoking information was abstracted from electronic and paper databases. We analyzed factors influencing BeBALLPT outcome, and its relation to blood-determined BeS and granulomatous inflammation. RESULTS: Positive BeBALLPTs contributed evidence of BeS in subjects without prior positive beryllium blood lymphocyte proliferation tests (BeBLPTs) and of pulmonary inflammation in persons without granulomata evident on lung biopsy. Positive BeBALLPTs were associated with positive BeBLPTs and more strongly with granulomata. The rate of both positive BeBALLPT and granulomata increased with time worked through 4 years and were lower in smoking subjects. The false negative rate of the BeBALLPT was 20%. CONCLUSION: A positive BeBALLPT is closely linked to the presence of granulomata on lung biopsy and can be considered as an indicator of lung inflammation in addition to BeS. The ability to use BeBALLPT as a substitute for the more risky lung biopsy is limited by the BeBALLPT false negative rate and lack of information on the false positive rate. It is not recommended that a positive BeBALLPT be considered sufficient evidence for both lung inflammation and BeS.


Assuntos
Berílio/toxicidade , Líquido da Lavagem Broncoalveolar/citologia , Granuloma do Sistema Respiratório/diagnóstico , Inflamação/diagnóstico , Hipersensibilidade Respiratória/diagnóstico , Adulto , Idoso , Ligas , Broncoscopia , Proliferação de Células/efeitos dos fármacos , Cobre , Feminino , Granuloma do Sistema Respiratório/patologia , Humanos , Inflamação/patologia , Linfócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Níquel , Exposição Ocupacional/efeitos adversos , Valor Preditivo dos Testes , Hipersensibilidade Respiratória/patologia , Adulto Jovem
2.
J Occup Environ Hyg ; 11(12): 781-92, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25357184

RESUMO

Inhalation of beryllium is associated with the development of sensitization; however, dermal exposure may also be important. The primary aim of this study was to elucidate relationships among exposure pathways in four different manufacturing and finishing facilities. Secondary aims were to identify jobs with increased levels of beryllium in air, on skin, and on surfaces; identify potential discrepancies in exposure pathways, and determine if these are related to jobs with previously identified risk. Beryllium was measured in air, on cotton gloves, and on work surfaces. Summary statistics were calculated and correlations among all three measurement types were examined at the facility and job level. Exposure ranking strategies were used to identify jobs with higher exposures. The highest air, glove, and surface measurements were observed in beryllium metal production and beryllium oxide ceramics manufacturing jobs that involved hot processes and handling powders. Two finishing and distribution facilities that handle solid alloy products had lower exposures than the primary production facilities, and there were differences observed among jobs. For all facilities combined, strong correlations were found between air-surface (rp ≥ 0.77), glove-surface (rp ≥ 0.76), and air-glove measurements (rp ≥ 0.69). In jobs where higher risk of beryllium sensitization or disease has been reported, exposure levels for all three measurement types were higher than in jobs with lower risk, though they were not the highest. Some jobs with low air concentrations had higher levels of beryllium on glove and surface wipe samples, suggesting a need to further evaluate the causes of the discrepant levels. Although such correlations provide insight on where beryllium is located throughout the workplace, they cannot identify the direction of the pathways between air, surface, or skin. Ranking strategies helped to identify jobs with the highest combined air, glove, and/or surface exposures. All previously identified high-risk jobs had high air concentrations, dermal mass loading, or both, and none had low dermal and air. We have found that both pathways are relevant. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: a file describing the forms of beryllium materials encountered during production and characteristics of the aerosols by process areas.].


Assuntos
Poluentes Ocupacionais do Ar/análise , Berílio/análise , Metalurgia , Exposição Ocupacional/análise , Aerossóis , Poeira/análise , Monitoramento Ambiental/métodos , Luvas Protetoras , Humanos , Pele
3.
Am J Ind Med ; 56(7): 733-41, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23450749

RESUMO

BACKGROUND: In 2000, a manufacturer of beryllium materials and products introduced a comprehensive program to prevent beryllium sensitization and chronic beryllium disease (CBD). We assessed the program's efficacy in preventing sensitization 9 years after implementation. METHODS: Current and former workers hired since program implementation completed questionnaires and provided blood samples for the beryllium lymphocyte proliferation test (BeLPT). Using these data, as well as company medical surveillance data, we estimated beryllium sensitization prevalence. RESULTS: Cross-sectional prevalence of sensitization was 0.7% (2/298). Combining survey results with surveillance results, a total of seven were identified as sensitized (2.3%). Early Program workers were more likely to be sensitized than Late Program workers; one of the latter was newly identified. All sensitization was identified while participants were employed. One worker was diagnosed with CBD during employment. CONCLUSIONS: The combination of increased respiratory and dermal protection, enclosure and improved ventilation of high-risk processes, dust migration control, improved housekeeping, and worker and management education showed utility in reducing sensitization in the program's first 9 years. The low rate (0.6%, 1/175) among Late Program workers suggests that continuing refinements have provided additional protection against sensitization compared to the program's early years.


Assuntos
Beriliose/prevenção & controle , Imunização , Exposição Ocupacional/efeitos adversos , Saúde Ocupacional , Prevenção Primária/organização & administração , Adulto , Beriliose/epidemiologia , Beriliose/imunologia , Berílio/sangue , Doença Crônica , Estudos Transversais , Feminino , Humanos , Exposição por Inalação , Masculino , Pessoa de Meia-Idade , Prognóstico , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Roupa de Proteção , Medição de Risco , Inquéritos e Questionários , Fatores de Tempo
4.
BMC Public Health ; 10: 5, 2010 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-20047684

RESUMO

BACKGROUND: Up to 12% of beryllium-exposed American workers would test positive on beryllium lymphocyte proliferation test (BeLPT) screening, but the implications of sensitization remain uncertain. METHODS: Seventy two current and former employees of a beryllium manufacturer, including 22 with pathologic changes of chronic beryllium disease (CBD), and 50 without, with a confirmed positive test were followed-up for 7.4 +/-3.1 years. RESULTS: Beyond predicted effects of aging, flow rates and lung volumes changed little from baseline, while DLCO dropped 17.4% of predicted on average. Despite this group decline, only 8 subjects (11.1%) demonstrated physiologic or radiologic abnormalities typical of CBD. Other than baseline status, no clinical or laboratory feature distinguished those who clinically manifested CBD at follow-up from those who did not. CONCLUSIONS: The clinical outlook remains favorable for beryllium-sensitized individuals over the first 5-12 years. However, declines in DLCO may presage further and more serious clinical manifestations in the future. These conclusions are tempered by the possibility of selection bias and other study limitations.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Beriliose/epidemiologia , Berílio/imunologia , Hipersensibilidade/epidemiologia , Exposição Ocupacional/efeitos adversos , Adulto , Beriliose/diagnóstico , Berílio/efeitos adversos , Doença Crônica , Feminino , Seguimentos , Humanos , Hipersensibilidade/diagnóstico , Hipersensibilidade/etiologia , Indústrias , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Fatores de Risco , Estados Unidos/epidemiologia
5.
Public Health Rep ; 124 Suppl 1: 112-24, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19618813

RESUMO

OBJECTIVES: In 2000, 7% of workers at a copper-beryllium facility were beryllium sensitized. Risk was associated with work near a wire annealing/pickling process. The facility then implemented a preventive program including particle migration control, respiratory and dermal protection, and process enclosure. We assessed the program's efficacy in preventing beryllium sensitization. METHODS: In 2000, the facility began testing new hires (program workers) with beryllium lymphocyte proliferation tests (BeLPTs) at hire and at intervals during employment. We compared sensitization incidence rates (IRs) and prevalence rates for workers hired before the program (legacy workers) with rates for program workers, including program worker subgroups. We also examined trends in BeLPTs from a single laboratory. RESULTS: In all, five of 43 legacy workers (IR = 3.8/1,000 person-months) and three of 82 program workers (IR = 1.9/1,000 person-months) were beryllium sensitized, for an incidence rate ratio (IRR) of 2.0 (95% confidence interval [CI] 0.5, 10.1). Two of 37 pre-enclosure program workers (IR = 2.4/1,000 person-months) and one of 45 post-enclosure program workers (IR = 1.4/1,000 person-months) were beryllium sensitized, for IRRs of 1.6 (95% CI 0.3, 11.9) and 2.8 (95% CI 0.4, 66.2), respectively, compared with legacy workers. Test for trend in prevalence rates was significant. Among 2,159 first-draw BeLPTs during 95 months, we identified seven months when high numbers of redraws were required, with one possible misclassification in this facility. CONCLUSIONS: Fewer workers became sensitized after implementation of the preventive program. However, low statistical power due to the facility's small workforce prevents a definitive conclusion about the program's efficacy. These findings have implications for other copper-beryllium facilities, where program components may merit application.


Assuntos
Poluentes Ocupacionais do Ar/intoxicação , Beriliose/prevenção & controle , Berílio/química , Indústria Química/normas , Exposição Ocupacional/prevenção & controle , Gestão da Segurança/métodos , Adulto , Beriliose/etiologia , Berílio/sangue , Cobre/química , Poeira , Segurança de Equipamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/métodos , Avaliação de Programas e Projetos de Saúde , Roupa de Proteção , Equipamentos de Proteção , Fatores de Risco
6.
Occup Environ Med ; 64(2): 134-40, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17043076

RESUMO

BACKGROUND: A 1998 survey at a beryllium oxide ceramics manufacturing facility found that 10% of workers hired in the previous 6 years had beryllium sensitisation as determined by the beryllium lymphocyte proliferation test (BeLPT). In response, the facility implemented an enhanced preventive programme to reduce sensitisation, including increased respiratory and dermal protection and particle migration control. AIM: To assess the programme's effectiveness in preventing sensitisation. METHODS: In 2000, the facility began testing newly hired workers for beryllium sensitisation with the BeLPT at time of hire and during employment. The sensitisation rate and prevalence for workers hired from 2000 to 2004 were compared with that for workers hired from 1993 to 1998, who were tested in the 1998 survey. Facility environmental conditions for both time periods were evaluated. RESULTS: Newly hired workers in both cohorts worked for a mean of 16 months. Of the 97 workers hired from 2000 to 2004 with at least one employment BeLPT result, four had abnormal results at time of hire and one became sensitised during employment. Of the 69 workers hired from 1993 to 1998 and tested in 1998, six were found to be sensitised. The sensitisation rate for the 2000-4 workers was 0.7-2.7/1000 person-months of employment, and that for the 1993-8 workers was 5.6/1000 person-months, at least 2.1 (95% confidence interval (CI) 0.6 to 8.4) and up to 8.2 (95% CI 1.2 to 188.8) times higher than that for the 2000-4 workers. The sensitisation prevalence for the 2000-4 workers was 1% and that for the 1993-8 workers was 8.7%, 8.4 (95% CI 1.04 to 68.49) times higher than that for the 2000-4 workers. Airborne beryllium levels for production workers for the two time periods were similar. CONCLUSIONS: A comprehensive preventive programme reduced beryllium sensitisation in new workers during the first years of employment, despite airborne beryllium levels for production workers that were similar to pre-programme levels.


Assuntos
Beriliose/prevenção & controle , Berílio/análise , Cerâmica , Exposição Ocupacional/prevenção & controle , Adolescente , Adulto , Idoso , Poluentes Ocupacionais do Ar/análise , Beriliose/etiologia , Proliferação de Células , Monitoramento Ambiental/métodos , Humanos , Ativação Linfocitária , Pessoa de Meia-Idade , Exposição Ocupacional/efeitos adversos , Saúde Ocupacional , Avaliação de Programas e Projetos de Saúde , Pele/química
7.
J Occup Environ Med ; 49(1): 96-101, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17215718

RESUMO

OBJECTIVE: Our aim was to reanalyze a nested case-control study of beryllium and lung cancer because we identified analysis and study design issues that could have led to the elevated odds ratios obtained in the study. METHODS: We reanalyzed the data using nontransformed exposure metrics instead of log-transformed metrics used in the publication. We identified and examined effects on estimated odds ratios of imbalances between cases and controls caused by the control selection method. RESULTS: This reanalysis found no elevated odds ratios for any exposure variable. CONCLUSION: : Our conclusions differ from the authors' interpretation that the findings are due to a causal relationship between beryllium exposure and lung cancer. Our alternative explanation is that they may be due to methodological problems that could have been controlled by closer matching of controls to cases. CLINICAL SIGNIFICANCE: This study challenges conclusions made from a large case-control study concerning beryllium-lung cancer associations. Occupational medicine practitioners may want to integrate findings from this study into advice they give beryllium-exposed workers concerned about lung cancer.


Assuntos
Berílio/efeitos adversos , Neoplasias Pulmonares/induzido quimicamente , Doenças Profissionais/induzido quimicamente , Estudos de Casos e Controles , Humanos , Modelos Logísticos , Neoplasias Pulmonares/mortalidade , National Institute for Occupational Safety and Health, U.S. , Doenças Profissionais/mortalidade , Exposição Ocupacional , Razão de Chances , Estados Unidos/epidemiologia
8.
J Occup Environ Med ; 48(2): 204-11, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16474270

RESUMO

OBJECTIVE: Little is known about the risk of sensitization and chronic beryllium disease (CBD) among workers performing limited processing of copper-beryllium alloys downstream of the primary beryllium industry. In this study, we performed a cross-sectional survey of employees at three copper-beryllium alloy distribution centers. METHODS: One hundred workers were invited to be tested for beryllium sensitization using the beryllium blood lymphocyte proliferation test (BeLPT); a sensitized worker was further evaluated for CBD. Available beryllium mass concentration air sampling data were obtained for characterization of airborne exposure. RESULTS: One participant, who had exposure to other forms of beryllium, was found to be sensitized and to have CBD, resulting in a prevalence of sensitization/CBD of 1% for all tested. CONCLUSIONS: The overall prevalence of beryllium sensitization and CBD for workers in these three copper-beryllium alloy distribution centers is lower than for workers in primary beryllium production facilities.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Beriliose/epidemiologia , Berílio/efeitos adversos , Hipersensibilidade Respiratória/induzido quimicamente , Hipersensibilidade Respiratória/epidemiologia , Adulto , Idoso , Poluentes Ocupacionais do Ar/análise , Ligas , Beriliose/patologia , Berílio/análise , Doença Crônica , Cobre , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ocupações , Prevalência , Estados Unidos/epidemiologia
9.
Inhal Toxicol ; 18(11): 901-10, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16864408

RESUMO

Despite more than 20 years of surveillance and epidemiologic studies using the beryllium blood lymphocyte proliferation test (BeBLPT) as a measure of beryllium sensitization (BeS) and as an aid for diagnosing subclinical chronic beryllium disease (CBD), improvements in specific understanding of the inhalation toxicology of CBD have been limited. Although epidemiologic data suggest that BeS and CBD risks vary by process/work activity, it has proven difficult to reach specific conclusions regarding the dose-response relationship between workplace beryllium exposure and BeS or subclinical CBD. One possible reason for this uncertainty could be misclassification of BeS resulting from variation in BeBLPT testing performance. The reliability of the BeBLPT, a biological assay that measures beryllium sensitization, is unknown. To assess the performance of four laboratories that conducted this test, we used data from a medical surveillance program that offered testing for beryllium sensitization with the BeBLPT. The study population was workers exposed to beryllium at various facilities over a 10-year period (1992-2001). Workers with abnormal results were offered diagnostic workups for CBD. Our analyses used a standard statistical technique, statistical process control (SPC), to evaluate test reliability. The study design involved a repeated measures analysis of BeBLPT results generated from the company-wide, longitudinal testing. Analytical methods included use of (1) statistical process control charts that examined temporal patterns of variation for the stimulation index, a measure of cell reactivity to beryllium; (2) correlation analysis that compared prior perceptions of BeBLPT instability to the statistical measures of test variation; and (3) assessment of the variation in the proportion of missing test results and how time periods with more missing data influenced SPC findings. During the period of this study, all laboratories displayed variation in test results that were beyond what would be expected due to chance alone. Patterns of test results suggested that variations were systematic. We conclude that laboratories performing the BeBLPT or other similar biological assays of immunological response could benefit from a statistical approach such as SPC to improve quality management.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Beriliose/diagnóstico , Berílio/efeitos adversos , Ativação Linfocitária/efeitos dos fármacos , Beriliose/imunologia , Beriliose/prevenção & controle , Humanos , Testes Imunológicos/estatística & dados numéricos , Exposição por Inalação , Estudos Longitudinais , Linfócitos/efeitos dos fármacos , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Exposição Ocupacional/efeitos adversos , Controle de Qualidade , Reprodutibilidade dos Testes , Estatística como Assunto/métodos
10.
J Occup Environ Med ; 57(2): 184-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25427172

RESUMO

OBJECTIVE: To describe how smoking correction factors based on comparing worker smoking prevalence with population smoking prevalence are biased if applied to an occupational incidence cohort. METHODS: Relative rates of smoking for shorter-tenure workers derived from occupational cohort lung cancer studies were applied to incidence and prevalence population tenure distributions to calculate relative smoking estimates. RESULTS: High smoking rates in short-tenure workers have little effect on prevalent worker rates (relative smoking estimates, 1.04 and 1.02) and much larger effect in occupational incidence populations (relative smoking estimates, 1.58 and 1.21), which have a much higher proportion of short tenure-workers. CONCLUSIONS: Smoking correction estimates derived from surveys of smoking habits in prevalent workers may introduce bias when applied to incidence workers because of very different proportions of short-tenure workers (length-time biased sampling).


Assuntos
Emprego/estatística & dados numéricos , Neoplasias Pulmonares/mortalidade , Doenças Profissionais/mortalidade , Fumar/epidemiologia , Viés , Estudos de Coortes , Humanos , Incidência , Prevalência , Estatística como Assunto , Fatores de Tempo
11.
J Occup Environ Med ; 57(6): 643-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25647318

RESUMO

PURPOSE: This study explores how highly correlated time variables (occupational cohort time scales) contribute to confounding and ambiguity of interpretation. METHODS: Occupational cohort time scales were identified and organized through simple equations of three time scales (relational triads) and the connections between these triads (time scale web). The behavior of the time scales was examined when constraints were imposed on variable ranges and interrelationships. RESULTS: Constraints on a time scale in a triad create high correlations between the other two time scales. These correlations combine with the connections between relational triads to produce association paths. High correlation between time scales leads to ambiguity of interpretation. CONCLUSIONS: Understanding the properties of occupational cohort time scales, their relational triads, and the time scale web is helpful in understanding the origins of otherwise obscure confounding bias and ambiguity of interpretation.


Assuntos
Estudos de Coortes , Fatores de Confusão Epidemiológicos , Doenças Profissionais/epidemiologia , Saúde Ocupacional , Fatores Etários , Berílio/efeitos adversos , Modificador do Efeito Epidemiológico , Humanos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/mortalidade , Exposição Ocupacional
13.
J Occup Environ Med ; 55(7): 839-45, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23787574

RESUMO

OBJECTIVE: Common variation is a statistical process-control term for variability associated with usual operating conditions. Special variation occurs when usual operating conditions are disrupted. The objective was to explore the implications for preventive occupational medicine practice of common and special variation in air-level exposure. METHODS: Illustrations are derived from US and UK beryllium facility databases. RESULTS: Special variation may be missed in finite sampling sets, giving a very inaccurate indication of the highest air levels experienced on the job. Depending on the toxicologic model, failure to assess special variation influences the meaningfulness of aspects of occupational prevention, from medical surveillance through risk management. CONCLUSIONS: Jobs and tasks should be characterized for special variation in addition to traditional air sampling. Both special variation and common variation should be considered in occupational medicine preventive practice.


Assuntos
Poluentes Ocupacionais do Ar/análise , Berílio/análise , Monitoramento Ambiental/métodos , Indústrias , Exposição Ocupacional/análise , Beriliose/prevenção & controle , Bases de Dados Factuais , Humanos , Modelos Estatísticos , Exposição Ocupacional/estatística & dados numéricos , Saúde Ocupacional , Vigilância da População , Reprodutibilidade dos Testes , Medição de Risco , Gestão de Riscos , Reino Unido , Estados Unidos
14.
Scand J Work Environ Health ; 38(3): 270-81, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21877099

RESUMO

OBJECTIVES: Exposure-response relations for beryllium sensitization (BeS) and chronic beryllium disease (CBD) using aerosol mass concentration have been inconsistent, although process-related risks found in most studies suggest that exposure-dependent risks exist. We examined exposure-response relations using personal exposure estimates in a beryllium worker cohort with limited work tenure to minimize exposure misclassification. METHODS: The population comprised workers employed in 1999 with six years or less tenure. Each completed a work history questionnaire and was evaluated for immunological sensitization and CBD. A job-exposure matrix was combined with work histories to create individual estimates of average, cumulative, and highest-job-worked exposure for total, respirable, and submicron beryllium mass concentrations. We obtained odds ratios from logistic regression models for exposure-response relations, and evaluated process-related risks. RESULTS: Participation was 90.7% (264/291 eligible). Sensitization prevalence was 9.8% (26/264), with 6 sensitized also diagnosed with CBD (2.3%, 6/264). A general pattern of increasing sensitization prevalence was observed as exposure quartile increased. Both total and respirable beryllium mass concentration estimates were positively associated with sensitization (average and highest job), and CBD (cumulative). Increased sensitization prevalence was identified in metal/oxide production, alloy melting and casting, and maintenance, and for CBD in melting and casting. Lower sensitization prevalence was observed in plant-area administrative work. CONCLUSIONS: Sensitization was associated with average and highest job exposures, and CBD was associated with cumulative exposure. Both total and respirable mass concentrations were relevant predictors of risk. New process-related risks were identified in melting and casting and maintenance.


Assuntos
Beriliose/etiologia , Berílio/toxicidade , Indústrias , Exposição por Inalação/efeitos adversos , Exposição Ocupacional/efeitos adversos , Medição de Risco/métodos , Adulto , Poluição do Ar em Ambientes Fechados/efeitos adversos , Beriliose/epidemiologia , Doença Crônica , Intervalos de Confiança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Ocupacional , Razão de Chances , Estatística como Assunto , Fatores de Tempo , Estados Unidos/epidemiologia , Local de Trabalho , Adulto Jovem
15.
J Occup Environ Med ; 53(10): 1187-93, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21926919

RESUMO

OBJECTIVE: Beryllium mine and ore extraction mill workers have low rates of beryllium sensitization and chronic beryllium disease relative to the level of beryllium exposure. The objective was to relate these rates to the solubility and composition of the mine and mill materials. METHOD: Medical surveillance and exposure data were summarized. Dissolution of BeO, ore materials and beryllium hydroxide, Be(OH)(2) was measured in synthetic lung fluid. RESULT: The ore materials were more soluble than BeO at pH 7.2 and similar at pH 4.5. Be(OH)(2) was more soluble than BeO at both pH. Aluminum dissolved along with beryllium from ore materials. CONCLUSION: Higher solubility of beryllium ore materials and Be(OH)(2) at pH 7.2 might shorten particle longevity in the lung. The aluminum content of the ore materials might inhibit the cellular immune response to beryllium.


Assuntos
Poluentes Ocupacionais do Ar/química , Beriliose/etiologia , Berílio/química , Hipersensibilidade/etiologia , Mineração , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Solubilidade , Poluentes Ocupacionais do Ar/efeitos adversos , Poluentes Ocupacionais do Ar/imunologia , Silicatos de Alumínio/efeitos adversos , Silicatos de Alumínio/química , Silicatos de Alumínio/imunologia , Berílio/efeitos adversos , Berílio/imunologia , Proliferação de Células , Células Cultivadas , Humanos , Linfócitos/efeitos dos fármacos , Fatores de Risco
17.
J Occup Environ Med ; 52(5): 505-12, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20431418

RESUMO

OBJECTIVE: We evaluated a workplace preventive program's effectiveness, which emphasized skin and respiratory protection, workplace cleanliness, and beryllium migration control in lowering beryllium sensitization. METHODS: We compared sensitization prevalence and incidence rates for workers hired before and after the program using available cross sectional and longitudinal surveillance data. RESULTS: Sensitization prevalence was 8.9% for the Pre-Program Group and 2.1% for the Program Group. The sensitization incidence rate was 3.7/1000 person-months for the Pre-Program Group and 1.7/1000 person-months for the Program Group. After making adjustments for potential selection and information bias, sensitization prevalence for the Pre-Program Group was 3.8 times higher (95% CI = 1.5 to 9.3) than the Program Group. The sensitization incidence rate ratio comparing the Pre-Program Group to the Program Group was 1.6 (95% CI = 0.8 to 3.6). CONCLUSIONS: This preventive program reduced the prevalence of but did not eliminate beryllium sensitization.


Assuntos
Ligas , Berílio/efeitos adversos , Indústrias , Exposição Ocupacional/prevenção & controle , Óxidos , Estudos Transversais , Feminino , Humanos , Masculino
18.
J Occup Environ Med ; 51(4): 480-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19322110

RESUMO

OBJECTIVE: The objective was to assess highly confounded patterns in a standardized mortality ratio (SMR) analysis of lung cancer in beryllium worker cohorts. METHODS: We used Cox proportional hazards single- and multi-variate models to assess confounding and the SMR patterns. RESULTS: We confirmed the lack of association of lung cancer with time worked. We could not confirm the original study's finding of lung cancer highly associated with earlier plants and or with workers hired in the 1940s compared to the 1950s. The pattern of higher rates of lung cancer with increasing latency was attenuated when covariates were added to the model. We could not exclude that the lower SMR and hazard ratios for workers hired in the 1960s might be related to assumed lower beryllium exposures. CONCLUSION: The patterns observed provide little support for an association of lung cancer with beryllium work factors. This result is likely due to the absence in the original study of a significant overall excess of lung cancer after smoking adjustment.


Assuntos
Berílio/toxicidade , Neoplasias Pulmonares/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Carcinoma de Pequenas Células do Pulmão/induzido quimicamente , Adulto , Estudos de Coortes , Humanos , Neoplasias Pulmonares/mortalidade , Pessoa de Meia-Idade , Exposição Ocupacional/estatística & dados numéricos , Ohio/epidemiologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Carcinoma de Pequenas Células do Pulmão/mortalidade , Análise de Sobrevida , Estados Unidos/epidemiologia , Adulto Jovem
19.
J Occup Environ Med ; 50(12): 1343-50, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19092488

RESUMO

OBJECTIVE: We followed a cohort of 136 beryllium oxide ceramics workers from 1992 to 2003, including those who left employment, for beryllium sensitization and chronic beryllium disease (CBD). METHODS: We invited the cohort's participation in current worker surveys in 1992, 1998, 2000, and 2002-2003, and in former worker surveys in 2000-2001 and 2003. We calculated 11-year cumulative incidences (after 1992 initial survey) of sensitization and CBD, both crude and corrected for interval censoring; and period prevalences (including 1992 findings), crude and corrected. RESULTS: In 1992, point prevalences were 6% sensitized and 4% CBD. We obtained follow-up on 83% of 128 not sensitized in 1992. Crude cumulative incidences for sensitization and CBD were 13% and 9%, respectively; corrected were 15% and 11%. Crude period prevalences for sensitization and CBD were 16% and 11%, respectively; corrected were 20% and 14%. Corrected period prevalences for pre-1992 machining work were 30% and 20%. CONCLUSIONS: With repeated testing over 11 years, total sensitization and CBD in this cohort were triple initial 1992 survey results.


Assuntos
Beriliose/epidemiologia , Berílio/efeitos adversos , Hipersensibilidade/epidemiologia , Exposição Ocupacional/efeitos adversos , Adulto , Idoso , Beriliose/sangue , Berílio/sangue , Broncoscópios , Cerâmica , Indústria Química , Doença Crônica , Estudos de Coortes , Feminino , Humanos , Hipersensibilidade/etiologia , Incidência , Linfócitos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fumar/epidemiologia , Inquéritos e Questionários
20.
J Occup Environ Med ; 49(9): 953-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17848851

RESUMO

OBJECTIVE: To test whether a frequently used cohort-nested case-control study design exaggerated exposure-response relationships because of unrecognized study design bias. Our aim was to evaluate empirically the performance of this complex study design. METHODS: We applied the design from one such study to a closely related cohort using randomly selected probands as cases. Values for average exposures were assigned to probands equal to, greater than, and less than those assigned to controls (matches). RESULTS: Under certain lag scenarios, the nested study design produced higher average exposure in probands compared with their matches, even when this was clearly not the case. CONCLUSIONS: Empirical evaluation demonstrated that the study design produced a biased case-control lagged exposure difference under the null hypothesis and could not distinguish qualitatively between null and alternate hypotheses. Empirical evaluation provided a useful check on results generated from a complex study design. It gave useful insight into the behavior of the index study design that was not otherwise readily deducible.


Assuntos
Berílio/toxicidade , Projetos de Pesquisa Epidemiológica , Neoplasias Pulmonares/mortalidade , Exposição Ocupacional/análise , Adulto , Fatores Etários , Viés , Estudos de Casos e Controles , Estudos de Coortes , Pesquisa Empírica , Humanos , Neoplasias Pulmonares/induzido quimicamente , Pessoa de Meia-Idade , Exposição Ocupacional/estatística & dados numéricos , Distribuição Aleatória , Estudos de Amostragem , Estatística como Assunto , Fatores de Tempo
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