The Missouri Poultry Cohort is a historical cohort investigation of mortality among workers highly exposed to the poultry oncogenic viruses which are suspected cancer causing agents in humans. Workers were also exposed to fumes from PVC-wrapping activities that contain chemicals known or suspected to produce cancer in humans The cohort mortality pattern is similar to what is often observed in occupational studies, where the healthy worker effect takes place As a group, cancer mortality also does not shows excess. However, cancer of bronchus, trachea & lung and cancer of kidney present statistically significant excess when the plants are introduced in the analysis. A positive dose response relationship was found for cancer of bronchus, trachea & lung, and cancer of kidney by means of latency and duration of employment analysis. In lesser extent, some cancers of the lymphopoietic system are also excessive: Lymphosarcoma & Reticulosarcoma, Leukemia & Aleukemia, and Cancer of All Other Lymphopoietic Tissues. Several other cancers also are excessive as cancer of stomach, cancer of large intestine, cancer of pancreas, cancer of bladder, cancer of cervix, cancer of thyroid, and cancer of central nervous system The cohort experienced an excessive mortality of Non-Malignant Respiratory Diseases. From the external causes of death, Motor Vehicle Accidents and Homicides & Other External Causes are also in excess. All other causes of death, covering a broad spectrum of diseases, also presents excess By taking race into consideration in the PMR analysis it was identified that the cancer of bronchus, trachea & lung excess is greater in the nonwhite female group. In lesser extent, it also suggests nonwhite-male excess of cancer of bronchus, trachea & lung The major limitations of this investigation are the relative short time of follow-up, the potential role of confounding factors that were not taken into account in the assessment of risk, and the small number of observed deaths in the cancers of interest The major strengths are the high intensity of chicken oncogenic viruses exposure in a homogeneous population, the assessment of missing information in the SMR analysis, and the consistency of the positive cancer results of this investigation with previous findings from occupational investigations in the Chicken Slaughtering/Processing Industry / acase@tulane.edu

There is growing evidence that natural disasters can trigger technological disasters, and that these joint events (also known as natechs) may pose tremendous risks to regions which are unprepared for such events. The recent floods across Europe in the summer of 2002 and the unprecedented multiple hazardous materials releases triggered by the Turkey earthquake of August 1999 were examples showing the potential danger of a natech disaster occurring near populated areas. However, there is scarce information available on the interactions between natural disasters and simultaneous technological accidents This dissertation provides an overview of the natech problem through the development of five related but independent research studies that identify natech disaster scenarios at industrial facilities subject to natural hazards, documents and analyzes natech incidents and risk management and emergency response practices for earthquake triggered hazardous materials releases during the Turkey earthquake of August 17, 1999, and assess risk management and emergency response for earthquake-induced chemical accidents in the US The dissertation demonstrates that the likelihood of joint natural and technological disasters is high, while preparedness for joint natechs is low Both the study of potential hurricane-triggered hazmat release scenarios and the study of hazmat releases during the Turkey earthquake demonstrated that joint natural disasters and technological disasters act synergistically to produce a much greater threat than either type of hazard alone. Furthermore, the different natural hazards associated with natechs all have the potential to produce a high amount of property damage, economic loss, and a high level of potential health threats to workers and the surrounding communities / acase@tulane.edu

Purpose. To determine the extent to which the MOR and PMR correctly identify true underlying associations between certain occupations/industries and mortality from specific cancers and what the important determinants are that contribute towards valid estimation of risk when they are employed Methodology. A literature review of relevant occupational risk factors for lung cancer, pleural cancer, acute myeloid leukemia and soft tissue sarcoma was conducted to determine the extent to which the study findings were supported by other studies. Death certificate data from 26 states in the United States that routinely code occupation and industry on the death certificates of decedents between 1985 and 1998 were used for this study. Both proportionate mortality and case-control studies were used to investigate the extent to which PMR and MOR were influenced by: (1) the choice of three different reference populations; and (2) reliability of the cause of death information as measured by detection and confirmation rates. It also determined whether the direction of bias remained consistent for cancers with well established (asbestos, benzene) and those with less established (solvents, diesel) carcinogens in certain occupations. Finally, similar but limited analyses were made using industry rather than occupation to determine whether estimates of the MOR and PMR differed Results. The results from the MOR and PMR investigation correctly identified risks for lung cancer, mesothelioma and acute myeloid leukemia, although they did not reflect the estimates published in the literature. An improvement in the odds ratio was observed for only lung and pleural/peritoneal cancer and soft tissue neoplasms when cancers caused by the same exposure under investigation were removed from the control group. In the case of the PMR, the proportionate cancer mortality ratio (PMCR) was an improvement over the PMR since it was possible to control for the healthy worker effect Both the MOR and PMR were influenced by the use of different measures of exposure (occupation titles, industry titles and a combination of both) Conclusions. The choice of reference diseases, type of exposure coding and confirmation and detection rates determines whether the MOR and PMR reliably identify associations between certain occupations and industries and mortality from specific cancers. Investigations based on exclusively on death certificate data ought not to be interpreted without substantial support of other rigorous investigations such as cohort studies, but are a valuable tool in epidemiological investigations for hypothesis generating / acase@tulane.edu

The purpose of this investigation was to explore relationships between accidents and demographic variables, attitudes, values and opinions about safety held by workers, and to compare accident rates (and performance records) of workers. Identification of attitudes toward safety that differentiate safe from unsafe employees could assist organizations in enhancing the safety of the workplace through identification or specialized training of potentially unsafe workers This study utilizes field data, collected by an offshore drilling company, using its Offshore Questionnaire (OQ). Information for the predictor variables (Offshore Questionnaire, Demographics, and BMCT) was provided by the company. Analyses were conducted to evaluate the hypotheses and to examine the dimensions of the OQ The findings in this study serve both to confirm some and contradict other previous findings. Kunce (1967) found a relationship between tenure and accidents. In the present study those positions requiring more experience--and, therefore, tenure--did have a significantly lower accident rate than entry-level positions It would appear that workers in the offshore industry are experiencing some of the same changes that the industry itself is experiencing. Rather than pioneers exploring new frontiers, workers today are experienced, well-trained professionals involved in oil and gas production and extraction. Working offshore is still a risky occupation, however the maturity of the industry allows many of these risks to be anticipated. The identification of these risks, combined with the selection and training of workers, could provide the industry the opportunity to be a safer and more productive workplace / acase@tulane.edu

Findings from a cohort mortality study between 1949-1980 of 28,900 members of a meatcutter's union in Baltimore, Maryland, suggested that certain workers in the meat industry have an excess risk of death from tumors of the hemopoietic/lymphatic systems (HLS). The aim of the present case-control study, nested in the Baltimore cohort study, was to investigate whether any job-categories and related tasks are associated with an excess of death from tumors of the HLS, taking into account length of exposure, as well as potential confounding factors in the assessment of risk While the cohort study was being concluded, all subjects who died from tumors of the HLS in Maryland were identified, and their next-of-kin interviewed by telephone to provide detailed information on history of occupation, lifestyle, diet, medical conditions, use of medications, leisure, etc. Controls were randomly selected from deceased members who had never been diagnosed with cancer of the HLS. Inclusion of controls was restricted to those who had lived at least as long as an assigned case. Additional data from the employment records of the Union and medical charts were used to validate occupational exposures and the cause of death Consistent results were obtained with (1) different statistical approaches viz. unmatched analyses with one control per case (n = 106) or two controls per case (n = 159) and matched analysis with one control per case; and (2) different sources of information including data from the interviews of the next-of-kin and limited data from the Union's records. The main findings are as follows: (1) Increased risks of all tumors of the HLS were observed among workers in the meat industry in general, and in abattoirs, grocery stores/supermarkets, and chicken-slaughtering plants specifically. Workers in meatpacking plants were at decreased risk. (2) Meat-related tasks with high exposure to oncogenic viruses such as butcher, work in kill/dress areas involving slaughtering activities were highly associated with tumors of the HLS. (3) The positive associations between job-categories and specific occupational tasks and tumors of the HLS remained stable after controlling for exposure to pesticides, working/living on pig farms, and exposure to X-rays. (4) The excess risks of tumors of the HLS seen throughout the meat industry, except in meatpacking plants, were mostly due to lymphomas. In supermarkets, myeloid tumors and multiple myeloma also contributed to the excess risk. There was a suggestion also of an increased risk of myeloid leukemia in abattoirs. (5) There was no sex-related difference in the risk of developing all tumors of the HLS in the meat industry in general and within each job-category, except for supermarket workers. In this department, lymphomas and leukemias were predominant in females who are exclusively engaged in wrapping, while multiple myeloma was over-represented in men. (6) The observed risks generally increased for long duration of employment in abattoirs and chicken-slaughtering plants, except in grocery stores/supermarkets where an inverse dose-response relationship, or lack of it was observed. (Abstract shortened by UMI.) / acase@tulane.edu

acase@tulane.edu

Cette thèse examine la question de la santé au travail des agents publics en abattoir dans sa multi-dimensionnalité. Elle livre une analyse du travail dans le secteur public non seulement à partir de son cadre institutionnel, mais aussi des multiples interactions, souvent interdépendantes, entre l’activité, les organisations et la trajectoire de la politique du contrôle en abattoir. Elle bat en brèche à la fois la présomption de qualité au travail dans le secteur public et la forte étanchéité de ce secteur. Elle montre comment les douleurs sont négociées, entre activité quotidienne et dispositifs de déclaration en maladie professionnelle et de reclassement. A partir des années 2000, une part croissante des agents de l’Etat en abattoir souffrent de troubles musculo-squelettiques. Les TMS sont l’occasion pour l’encadrement intermédiaire de négocier avec les abattoirs mais aussi d’énoncer le « vrai travail » des agents en abattoir. La mise sur l'agenda de la santé au travail des agents affectés dans les abattoirs surgit dans le contexte de redéfinition des missions de l'Etat et les évolutions de la politique du contrôle en abattoir contribuent tantôt à faire émerger la santé au travail, tantôt à l’occulter en laissant de côté la question du devenir des agents dont les missions évoluent et dont le métier est susceptible de disparaître. Au croisement de la sociologie des groupes professionnels, de la santé au travail et de la sociologie de l’action publique, le cadre d’analyse propose d’articuler les régulations liées à la santé et aux conditions de travail à celles de l’activité et du métier d’inspecteur lui-même. / This thesis considers the occupational health of public officials in slaughterhouses in its multi-dimensionality. It provides an analysis of work in the public sector, not only from its institutional framework, but also from the many interactions, often interdependent, between the activity, the organizations and the trajectory of food safety policy. It undermines both the presumption of quality at work in the public sector and the strong tightness of this sector. It shows how pain is negotiated, between daily activity and occupational disease reporting and reclassification schemes. From the 2000s, a growing proportion of officials in slaughterhouses suffered from musculoskeletal disorders. MSDs are an opportunity for middle management to negotiate with slaughterhouses, but also to state the "real work" of slaughterhouse agents. The agenda setting of the occupational health of the agents affected in the slaughterhouses arises in the context of redefining the missions of the State and the evolutions of the food safety policy contribute sometimes to make emerge health at work, to overshadow it by leaving aside the question of the future of those officials whose missions evolve and whose profession is liable to disappear. At the crossroads between the sociology of professions, occupational health and the sociology of public action, the analysis framework proposes to articulate the regulations related to health and working conditions to those of the activity and the profession of inspector himself.

Background : Atrazine is an agricultural herbicide used extensively in corn production worldwide. Atrazine is an endocrine disruptor and has been linked to many other deleterious health outcomes. Exposure assessment studies have been carried out in Iowa among farm and non-farm populations. However, commercial pesticide applicators have been left out of those studies. Atrazine is also used in developing countries in grain production. In developing countries there is great concern about acute pesticide poisonings, but chronic exposure to less acutely toxic pesticides has not been studied extensively. This study assessed the in-home contamination of atrazine among commercial pesticide applicators in Iowa and then quantitatively analyzed these results with results from similar studies. Occupational inhalation exposure to atrazine was also assessed in Honduras. Methods : Dust samples were taken from 29 commercial pesticide applicator households in four different locations. This sampling was done once during the atrazine application season and again six months later during winter months to assess atrazine persistence. Occupational and household characteristics were analyzed for associations with atrazine dust levels. Data from two previous studies that analyzed farm and non-farm household dust samples for atrazine were combined with data from the commercial applicator's homes. This new and larger dataset was analyzed to identify which population has the greatest risk for take-home atrazine exposure and what determinants were associated with in-home atrazine dust levels. Lastly, corn production practices in Honduras were evaluated and personal air samples were taken from pesticide applicators during atrazine application to assess inhalation exposure. Results : The first study found that atrazine levels persist into the winter months in the homes of commercial applicators. Atrazine handling (days, pounds, and acres sprayed) were all positively associated with in-home atrazine levels. Commercial applicators that change their shoes inside had higher atrazine levels. More frequent floor cleaning was associated with lower atrazine levels. The second study identified commercial applicators' homes as the most contaminated compared with farmers who apply atrazine to their own land, farmers who hire out atrazine application, and non-farm homes. Farmers that apply their own atrazine also had significantly higher atrazine levels in their homes. The association between atrazine handling and household atrazine levels was highly significant in this study (p < 0.001). In Honduras, atrazine is applied to corn fields with tractor/boom equipment and manual backpack sprayers. Despite applying about one-fifteenth the amount of atrazine, backpack sprayers are exposed to nearly equal amounts of atrazine via inhalation exposure and likely have greater exposure via the dermal route. Among backpack sprayers, which type of spray nozzle used is associated with inhalation exposure. Among tractor/boom applicators, tractor drivers have much lower inhalation exposure than workers who operate and observe the boom. Conclusions : The amount of atrazine handled is the most important determinant for predicting in-home atrazine levels in Iowa. Ubiquitous atrazine contamination and its distribution within homes and among household type provide strong evidence for the take-home pathway. While some improvements have been made in Honduras regarding pesticide application, poor farm workers and small farmers still use antiquated pesticide application techniques which leads to a higher risk of inhalation and dermal exposure.

The overall goals of this dissertation are: 1) to better quantify the spatial heterogeneity of coarse particulate matter (PM10-2.5) and its chemical composition; and 2) to evaluate the performance (accuracy and precision) of passive samplers analyzed by computer-controlled scanning electron microscopy with energy-dispersive X-ray spectroscopy (CCSEM-EDS) for PM10-2.5. For these goals, field studies were conducted over multiple seasons in Cleveland, OH and were the source of data for this dissertation. To achieve the first goal, we characterized spatial variability in the mass and composition of PM10-2.5 in Cleveland, OH with the aid of inexpensive passive samplers. Passive samplers were deployed at 25 optimized sites for three week-long intervals in summer 2008 to characterize spatial variability in components of PM10-2.5. The size and composition of individual particles were determined using CCSEM-EDS. For each sample, this information was used to estimate PM10-2.5 mass and aerosol composition by particle class. The highest PM10-2.5 means were observed at three central industrial urban sites (35.4 Μg m-3, 43.4 Μg m-3, and 47.6 Μg m-3), whereas lower means were observed to the west and east of this area with the lowest means observed at outskirt suburban background sites (12.9 Μg m-3 and 14.7 Μg m-3). Concentration maps for PM10-2.5 and some compositional components of PM10-2.5 (Fe oxide and Ca rich) show an elongated shape of high values stretching from Lake Erie south through the central industrial area, whereas those for other compositional components (e.g., Si/Al rich) are considerably less heterogeneous. The findings from the spatial variability of coarse particles by compositional class analysis, presented in Chapter II of this dissertation, show that the concentrations of some particle classes were substantially more spatially heterogeneous than others. The data suggest that industrial sources located in The Flats district in particular may contribute to the observed concentration variability and heterogeneity. Lastly, percent relative spatial heterogeneity (SH%) is more consistent with spatial heterogeneity as visualized in the concentration surface maps compared to the coefficient of divergence (COD). The second goal was achieved by assessing the performance of passive samplers analyzed by CCSEM-EDS to measure PM10-2.5 (Chapter III) and investigating potential sources of variability in the measurement of PM10-2.5 with passive samplers analyzed by CCSEM-EDS (Chapter IV). Data for these analyses were obtained in studies conducted in summer 2009 and winter 2010. The precision of PM10-2.5 measured with the passive samplers was highly variable and ranged from a low coefficient of variation (CV) of 2.1% to a high CV of 90.8%. Eighty percent of the CVs were less than 40%. This assessment showed the CV for passive samplers was greater than that recommended by the United States Environmental Protection Agency (EPA) guidelines for the Federal Reference Method (FRM). Several CV values were high, exceeding 40% indicating substantially dissimilar results between co-located passive samplers. The overall CV for the passive samplers was 41.2% in 2009 and 33.8% in 2010. The precision when high CVs > 40% (n = 5 of 25) were excluded from the analysis was 24.1% in 2009 and 18.2% for 2010. Despite issues with precision, PM10-2.5 measured with passive samplers agreed well with that measured with FRM samplers with accuracy approaching EPA Federal Equivalent Method (FEM) criteria. The intercept was 1.21 and not statistically significant (p = 3.88). The passive to FRM sampler comparison (1:1) line fell within the 95% confidence interval (CI) for the best-fit linear regression and was statistically significant (p < 0.05). However, several data points had large standard deviations resulting in high variability between co-located passive samplers (n = 3), which extend outside of the 95% CI's. The passive sampler limit of detection (LOD) for the CCSEM method was 2.8 Μg m-3. This study also showed certain samples had higher CVs and that further investigation was needed to better understand the sources of variability in the measurement of PM10-2.5 with passive samplers. Sources of variability observed in the measurement of PM10-2.5 with passive samplers analyzed by CCSEM were explored in Chapter IV of this dissertation. This research suggests mass concentrations greater than 20 Μg m-3 for week long samples are needed on the passive sampler substrate to obtain overall CVs by mass less than 15%. It also suggests that greater than 55 particle counts within a compositional class are needed to reduce analytical CVs to less than 15%. Another finding from this study was increasing the concentration from 6.2 to 10.6 Μg m-3 increases the CCSEM analytical precision by mass 38% and by number 75% for random orientation. Also certain compositional classes appeared problematical for precision of passive sampler measurements. For example, the presence of salt plus moisture introduces challenges for CCSEM analysis through the wetting of salt crystalline particles which dissolve creating a displaced dry deposition pattern of particles upon subsequent evaporation. This process can falsely elevate or reduce the particle count and alter its distribution on the sampling media.

Each hydraulic fracturing well uses up to 5,000 tons of silica-containing sand, or proppant, during its operational lifetime. Over one million wells are currently in operation across the continental United States. The resulting increase in demand resulted in the production of 54 million metric tons of sand for use as hydraulic fracturing proppant in 2015. The goal of this study was to determine the relative risk of occupational exposure to respirable crystalline silica to workers performing tasks associated with mining, processing, and transport of proppant. Sand samples were aerosolized in an enclosed chamber. Bulk and respirable samples were submitted to a commercial lab for silica analysis. A risk ratio was calculated by comparing respirable dust concentrations to the current occupational safety regulations. Raw sand produced higher concentrations of respirable dust and a higher risk ratio (3.2), while processed dust contained higher percentages of respirable crystalline silica but a lower risk ratio (0.5). When vibration was introduced prior to aerosolization, concentrations tended to increase as vibration times increased, resulting in an increase of the associated risk ratio (2.3). Results of the study indicate that workers in sand mines and workers exposed to proppant that has undergone low-frequency vibration are at increased risk of exposure to respirable crystalline silica compared to workers who are exposed to proppant that has not undergone vibration.