Includes abstract. / Includes bibliographical references (leaves 47-52). / The aim of this study was to investigate the exposure-response relationship between the concentration of inhalable manganese dust and subclinical nervous system outcomes amongst workers in a South African manganese smelter with a view to identifying any exposure threshold below which adverse effects do not occur.

Background: Skin cancer is an increasing worldwide public health concern. Rates of melanoma and skin cancer continue to rise worldwide, creating a significant public health need for detection. In 2003, nearly 54,000 Americans were diagnosed with melanoma with an expected 7,700 deaths. The visual skin exam is an effective secondary prevention tool in detecting melanoma and nonmelanoma skin cancer and may be implemented in occupational medical clinics. Methods: Applying the results of a comprehensive literature review of skin cancer screening efforts in communities and workplaces to occupational medicine. Results: Skin cancer screening efforts have identified high-risk populations for melanoma and nonmelanoma skin cancer and may detect suspicious lesions early. Conclusions: Occupational physicians may be the only healthcare provider with the opportunity to screen a high-risk population, particularly males over age 50. Integrating a skin examination into pre-employment or periodic examinations would expend minimal time and funds while potentially preventing worker morbidity and mortality. Screening for skin cancer at the workplace may also fulfill a public health need. The integration of skin cancer screening into occupational medicine may simultaneously improve worker health and increase the value of the occupational medicine physician.

Over the past 20 years, the "workplace substance abuse prevention industry" has grown enormously in size and has become more sophisticated in its marketing approach. Drug testing alone has become a $6 billion industry. Employee assistance programs are now widely used by employers at significant cost. This thesis presents a brief review of drug use patterns as related to occupational injuries together with a history of workplace testing. Results from studies suggest that drug-free workplace programs are an important public health approach to improving workplace health and safety through early intervention and, quite possibly, substance abuse prevention.

The public health significance of low back pain results from the economic and social burdens it places on industrialized societies. The primary objective of this paper is to create a definition of low back pain recurrence based on present scientific literature. No unified definition has been offered in current research and a universally accepted definition will help advance the study and treatment of low back pain recurrence. The need for a unified definition comes from the fact it is not easy to compare the various studies of recurrent low back pain. This limitation affects the treatment patients are given and the outcomes they experience. Building on our primary objective of creating a unified definition of low back pain we will then take the definition and use it to evaluate available databases (UPMC Health Plan and Workers Compensation) for low back pain recurrence. The definition and the available data will be used to evaluate the costs, both direct (medical and workers compensation) and indirect (related to lost work time, etc, associated with low back pain). This will be useful in comparing the medical and personnel costs aspects of patients with recurrent low back pain to those without recurrent low back pain. By performing this analysis we will be able to estimate the costs savings of effective treatment for low back pain recurrence. Using the definition of low back pain recurrence developed and the data and clinical resources available we will develop an intervention to reduce recurrence rates of work related low back pain. Specific treatment groups will be identified and compared in a prospective analysis to the usual care low back pain patients receive. The results of this aspect of the study will be used to decide if the proposed treatment was able to reduce medical and other costs as predicted when compared to any increased costs specific treatments may entail. Finally, the rationale for a new universally accepted definition of recurrent low back pain will be given. I will then give a brief outline of a step-wise process to be used by future researchers in addressing recurrent low back pain.

In a program announcement in 2005, The Office of Biodefense Research, the National Heart, Lung and Blood Institute, and the National Institutes of Health expressed concern about an issue of significant public health importance: the US population's potential exposure to aerosolized, inhaled harmful chemicals possibly liberated as part of bioterrorism attacks against assembled groups of the civilian populace. The primary stated objective of the program was to encourage research about how the upper respiratory tract and lungs respond to acute exposure to highly toxic chemicals and subsequent inhalation, so that preventive strategies can be improved, antidotes devised to lessen initial irritation of mucosal surfaces, mucosal absorption minimized, and acute lung injury causing pulmonary edema counteracted. In the context of this objective, a review of the basic and applied science of inhalation toxicology was undertaken and a research proposal developed to demonstrate the relevance of an established mouse bioassay, documented to identify and quantify the effects of inhaled agents at all three regions of the respiratory tract, by evaluating the inhalation toxicity of methyl isocyanate, an agent known to affect all three regions of the respiratory tract. Human observational methyl isocyanate exposure data from the Bhopal industrial accident are available, as are experimental animal exposure data, offering the opportunity to further establish the reproducibility and validity of the bioassay. In addition, the mouse biosassay detects effects of inhaled agents at concentrations below those at which histopathological changes occur, enabling the rapid screening of administered treatments and antidotes for effectiveness. This capacity is of fundamental importance in the development of future therapeutic agents. With experience gained in the practical management of the experimental apparatus with the methyl isocyanate proposal, a study using the mouse bioassay to reproduce unpublished data investigating therapeutics against the inhalation toxicity of ricin would be proposed at a future date. Ricin is of outmost importance for biodefense since it is extremely potent and readily available. Furthermore, no antidote or treatment exists against this agent and the unpublished data on possible treatment should be pursued..

Cadmium (Cd) is a heavy metal with public health importance because it is known to present environmental and occupational hazards and a threatening to public health. Cd has negative effects on the liver, kidney, and male fertility. However, relatively little is known about the molecular toxicology of Cd in the epithelial cells of the male reproductive system. Thus, we studied the effects of Cd on the critical metal binging protein, metallothionein-1 (MT-1), in the epididymis of the intact rat. CdCl2 (2 mg/kg/day) was administered for 10 days via minisomotic pumps implanted subcutaneously in mature male rats, and the rats were then sacrificed and their tissues , including the kidney and epididymis, were quickly frozen and examined via immunohistochemistry for MT-1, vacuolar H+ - ATPase (V-ATPase) at confocal microscopic level or MT-1 (Western blot). We observed a significant upregulation of MT-1 expression in kidney proximal tubules by immunofluorescence and Western blot. MT-1 was positive over most of the basal cells (BC) along the epididymal duct and part of the clear cells (CC) in the caudal duct that co-localized with V-ATPase, a CCs marker. MT-1 expression was upregulated in distal caudal CCs after Cd treatment. However, the overall MT-1 expression assayed by Western blot in the epididymal duct decreased after treatment. This study indicated the validity of Cd administration via subcutaneous minipump. MT-1 was upregulated in caudal CCs after Cd treatment. The MT-1 change deserves further investigation.

Despite advances in technology and medicine, safety for working adolescents still challenges 21st century Americans. One would think that by now, in the beginning of the new millennium, America would have cured this disease of child labor that infects its younger population. Yet, injuries still maim and kill Americas working youth. Politicians speak out against child obesity, and both celebrities and ordinary citizens criticize school violence, especially after a Columbine or Virginia Tech massacre. Human rights activists picket clothing lines that depend upon the work of underpaid children in developing countries, and Congress holds hearings to ensure that American consumers do not buy goods produced by these exploited children. However, health care providers, legislators, and the general public often relegate child labor to the back burner. Moreover, many diminish the role of child labor in the United States by viewing child labor as a social, economic, and political problem limited to developing countries. The employment of children in the work force should be in the forefront of domestic health policy because of its social and economic significance to public health. Even though current societal awareness indicates some understanding of the health risks of adolescent workers, statistics continue to show a bleak picture of preventable workplace injuries and fatalities of this vulnerable population. This paper defines child or youth as any individual 17 or younger who engages in some kind of work. In discussing youth employment, the paper does more than just describe child labor laws; it also focuses on the unique traits of this young population and the trends that characterize its employment. This gives an identity to the faceless young men and women who deal with the risks of the industrial and agricultural work places. Once presenting the current statistics on injuries and fatalities incurred by youth in both the industrial and agricultural sectors, the paper compares the similarities and differences in the major industries between youth and adult workers. It then moves into the legal arena, describing what has been done and what still needs to happen to combat child labor problems.

Idiopathic Pulmonary Fibrosis (IPF) is a chronic and progressive form of interstitial lung disease characterized by inflammation and abnormal tissue repair ultimately leading to decreased pulmonary function and death. Risk factors for IPF are largely unknown and medical treatment offers a poor prognosis due to the lack of effective treatment options. Survival outcomes were analyzed for a cohort of 331 patients. The median age at clinical evaluation for IPF was 69 years. Subjects survived an average of 21.82 months after diagnosis, with a higher survival in females than in males. Males had a risk 2.85 times higher than females of death. Subjects older than 69 years of age had a relative risk of dying of 1.6 in comparison to subjects younger than 69 years. Predictors of survival after lung transplant were also analyzed in a cohort of 990 lung transplanted patients. The overall survival was 41.6%, (41.5 % in males, and 41.8 % in females), the average length of the follow up was 45.84 plus or minus 51.98 months (range 0 to 282.47 months). Females tend to live longer than males: 50.75 plus or minus 55.41 months versus 40.64 plus or minus 47.60 months, respectively. Males had a risk of dying during the follow up that was 1.18 (95% CI 1.01-1.40) relative to females, after adjusting for ethnicity, age, smoking status, diagnosis and donor characteristics. Females who had at least one full term pregnancy during their life had better survival rates than females who had no full term pregnancies. Our results of a better survival after lung transplant in females (particularly females with at least one pregnancy) support the hypothesis of a hormonal contribution to survival and of the development of immunotolerance after pregnancy. The public health significance includes the use of the current study as a model in understanding the role of immunity in cancer development. The age-adjusted incidence rate is 555.8 per 100,000 men and 411.3 per 100,000 women per year (2000-2004), and the combined lifetime risk of cancer is approximately 1 in 2. Thus, any further understanding of cancer causes would be worthwhile in cancer prevention and treatment efforts.

BACKGROUND: Occupational epidemiology plays an important role in public health by describing and analyzing environmental and occupational hazards affecting workers, and sometimes the general public. Since the results of occupational epidemiology serve as the background for public policy making as well as individual worker and employer decisions, the accuracy of these studies is quite important. No previous studies have attempted to describe the occupational epidemiology literature. METHODS: This study examines author affiliation, funding source, outcome, and topic in two major occupational health journals published in the United States in order to describe the literature over the past three decades and to find associations between the stated variables. RESULTS: Associations between U.S. industry funded or U.S. industry authored studies and outcome were observed, with an increase in negative outcome (pro-industry) studies as compared to U.S. federally funded or U.S. university authored studies. An overall increase in international sponsoring and performance of occupational epidemiology has also been observed over the past three decades. CONCLUSIONS: The published occupational epidemiology literature in two U.S. journals demonstrated associations between funding source and outcome as well as author affiliation and outcome. Further research is recommended to follow up on the findings of this study.

Background: Recent studies have suggested that aside from the inhalational route, skin exposure may also play an important role in the sensitization to allergens, resulting in adverse allergic respiratory outcomes including asthma in workers exposed to these agents. This appears to be reported more commonly for low molecular weight agents such as isocyanates and some cleaning agents. This study investigated whether skin symptoms, in the presence or absence of allergic sensitization, can predict the development of allergic respiratory outcomes and asthma in bakery workers. Methods: A cohort study investigated 263 bakery workers using a modified ECRHS questionnaire; immunological tests including skin prick tests for common local aeroallergens (ALK-Abello´ A/S, Horsholm, Denmark), Phadiatop and serum-specific IgE to bakery allergens (wheat, rye and fungal α-amylase); and pulmonological tests including spirometry, non-specific bronchial hyperresponsiveness, and fractional exhaled nitric oxide (FeNO), after a 4 year period. Results: Workers’ median age was 32 years (IQR: 26-38), 50% were female, 54% were ever smokers and 32% were atopic. At baseline, 26% of workers were sensitized to bakery allergens, skin symptoms were present in 22% and 11% reported work-related skin symptoms (WRSS). 3 While the incidence of general upper (19%) and lower (22%) respiratory symptoms over the follow-up period were very similar, work-related upper (29%) respiratory symptoms were higher than lower (20%) respiratory symptoms. However, the incidence of allergic sensitization to bakery allergens was only 8% and a new asthma diagnosis present in 4% over this period. In multivariate adjusted (gender, atopy and smoking status) regression models, having a history of skin symptoms was associated with an increased risk of developing work-related lower respiratory symptoms - WRLRS (RR=2.2, 95% CI: 1.03-4.83), while having clinically significant symptoms of eczema or urticaria was associated with an increased risk of reporting general upper respiratory symptoms (RR=5.5, 95% CI: 1.30-24.20) as well as WRLRS (RR= 4.8, 95% CI: 1.60-14.40). Furthermore, WRSS was associated with an increased risk of general upper respiratory symptoms (RR=5.1, 95% CI: 1.31-19.81), WRLRS (RR=4.1, 95% CI: 1.43-11.85) and elevated FeNO levels (FeNO>25ppb: RR=2.9, 95% CI: 1.19-7.28). The association between clinically significant skin symptoms or WRSS and new onset upper or lower respiratory symptoms were modified by use of dermal personal protective equipment. Infrequent or absent glove usage was associated with a higher risk (RR=5.3, 95% CI: 1.54-18.43) of having new onset WRLRS. Conclusion: Skin symptoms, more so if work-related, appear to be associated with future development of general and work-related upper and lower respiratory symptoms and inflammatory markers suggestive of asthma in bakery workers.