A pilot study on the association between job stress and repeated measures of immunological biomarkers in female nurses.

OBJECTIVE: To evaluate the immunosuppressive effects of job stress in female nurses, an 8-month longitudinal study was conducted at a major university hospital. METHODS: Four groups of ten subjects each were constructed to represent high versus low objective stress and high versus low subjective stress based on their responses to a job stress questionnaire and objective stress ratings of the hospital's work units. Number of white blood cells (i.e., T cells, B cells, and natural killer cells), and lymphocytic proliferation to mitogens (concanavalin A, phytohemagglutinin, and pokeweed) and toxoid (tetanus) were measured by flow cytometry and radioimmunoassay. Serum levels of hydrocortisol, IL-1ß, IFN-γ, and TNF-α, and salivary IgA were measured by enzyme-linked immunosorbent assay. The data were analyzed by repeated measures analysis of variance controlling for age and smoking. RESULTS: The level of white blood cells was lower among high objective stress group (median: 7,170/m(3); range: 5,386-10,057) compared with that among low objective stress group (8,063; 5,888-9,875) (P = 0.03), however, no other cellular blood variables were found to be significant. In terms of humoral immuno-biomarkers, the level of TNF-α was moderately lower among high objective stress group (1.7 ng/ml; 0.3-2.7) compared with that among low objective stress group (2.2; 0.5-3.5) (P = 0.07), whereas the level of total sIgA was significantly higher among higher objective stress group (72.9 end-point titer/mg/ml/min; 14.4-153.4) compared with that among low objective stress group (44.8; 9.9-123.8) (P = 0.02). CONCLUSION: The results of the study suggest that psychological job stress affects the levels of some immunological biomarkers in female nurses.

General principles of medical surveillance: implications for workers potentially exposed to nanomaterials.

OBJECTIVE: As potential occupational exposure to nanomaterials becomes more prevalent, it is important that the principles of medical surveillance be considered for workers in the nanotechnology industry. METHODS: The principles of medical surveillance are reviewed to further the discussion of occupational health surveillance for workers exposed to nanomaterials. RESULTS: Because of the rapid evolution of nanotechnology, information may not be available to make a well-informed determination of all factors needed to evaluate risk of health effects from occupational exposure to nanomaterials. CONCLUSION: Every workplace dealing with engineered nanomaterials should conduct hazard and exposure assessments as part of an overall surveillance needs assessment for nanotechnology workers. In workplaces where risk is felt to be present, or at least cannot be ruled out, initiation of medical surveillance is prudent to protect workers' health.

Nanomaterials and worker health: medical surveillance, exposure registries, and epidemiologic research.

OBJECTIVE: This article provides an overview of the issues that arise with medical surveillance, exposure registration, and epidemiologic research involving nanomaterial workers. METHODS: An occupational health perspective is applied to detecting risks in nanomaterial workers individually and as a group. RESULTS: General principles for medical surveillance, exposure registration, and epidemiologic research are identified. A model Nanomaterial Worker Health Study is for consideration. CONCLUSIONS: The Nanomaterial Worker Health Study can be developed as a tangible action in assuring the public that steps are being taken to learn of any adverse effects from exposure to nanomaterials.

Medical surveillance, exposure registries, and epidemiologic research for workers exposed to nanomaterials.

While there is a growing body of information about hazards of nanomaterials, little is known about the risks to workers exposed to them. However, workers are the first people in society that are being exposed to the growing inventory of "nano-enabled" products in commerce. The number of workers involved in the investigation, manufacture, production, and disposal of these types of products is growing. Although toxicologic research is still the highest priority, it is time to actively anticipate the health needs of workers. To date, precautionary risk management approaches have been widely advocated. Now there is a need to initiate an evolving process to identify the issues in medical surveillance, utilization of exposure registries, and the conduct of epidemiologic research. Each of these are related complex endeavors that build on the toxicologic evidence and extent of exposure. There is a need to assess the scientific basis and research needs for determining early functional changes, organ system and disease responses for use in targeted medical surveillance. There is also need for development of criteria for extrapolating toxicological data in biological systems to predict the risk of adverse outcomes in humans. In the meantime, exposure registries may be pivotal in helping societies act in the face of uncertainty in a precautionary manner, but legal, ethical, and logistical issues need resolution. Epidemiologic research will build on these efforts and may ultimately contribute critical definitive rationale for medical screening, risk assessment and management.

Clinical use of immunoassays in assessing exposure to fungi and potential health effects related to fungal exposure.

OBJECTIVE: To review and summarize current evidence regarding the proper role of immunoassays in clinical assessments of exposure to fungi and health effects related to fungal exposure. DATA SOURCES: We reviewed relevant scientific investigations and previously published reviews concerning this topic. STUDY SELECTION: The authors' clinical, laboratory, and public health experiences were used to evaluate relevant data for scientific merit. RESULTS: Testing to determine the presence of IgE to specific fungi may be a useful component of a complete clinical evaluation in the diagnosis of illnesses that can be caused by immediate hypersensitivity such as allergic rhinitis and asthma. Detection of IgG to specific fungi has been used as a marker of exposure to agents that may cause illnesses such as hypersensitivity pneumonitis. However, the ubiquitous nature of many fungi and the lack of specificity of fungal antigens limit the usefulness of these types of tests in the evaluation of potential building-related illness and fungal exposure. Specific serologic tests (such as tests for cryptococcal antigen, coccidioidal antibody, and Histoplasma antigen) have been shown to be useful in the diagnosis of some fungal infections, but these are the exception not the rule. CONCLUSIONS: There is currently not enough scientific evidence to support the routine clinical use of immunoassays as a primary means of assessing environmental fungal exposure or health effects related to fungal exposure. Health care providers who care for persons expressing concerns about the relationship of symptoms to potential exposure to fungi are advised to use immunoassay results with care and only as an adjunct to a comprehensive approach to patient care.