Video exposure monitoring (VEM) consists of taking video recording of a worker performing a task at the same time while personal monitoring is performed using a direct-reading instrument. The video and the exposure data are then merged and synchronized and analyzed together. The industrial hygienist conducting the VEM is able to identify any high level of exposure and note the time when the excessive level happened. The corresponding task of the worker is then identified based from the video shot taken at the same time as the exposure data. The objective of this thesis was to study the implementation of a low cost means of conducting VEM in workplaces with hazardous chemicals in use, by utilizing commercially-available direct reading instruments, a digital video camera, and either off-the-shelf software or freeware downloadable from the internet. It was intended that VEM done by such means would still have the same ability of conveying workplace exposure results and, at the same time, capable of pinpointing work areas where controls could be initiated to reduce excessive levels of contaminants.

Thesis (M.Tech.:Chiropractic)-Dept. of Chiropractic, Durban Institute of Technology, 2005 126 leaves, Annexures A-N / Emergency medical personnel have a number of occupational risk factors that are listed in the reviewed literature (Davis and Heaney 2000, Volinn 1997 and Andersson 1999) as risk factors for low back pain. Physical lifting and carrying of patients and equipment increases stress on the lower back, while occupational stress and a high level of patient responsibility are mental risk factors (Davis and Heaney, 2000). Emergency medical personnel that spend long hours in response vehicles, ambulances or helicopters are exposed to vibrational stressors and may therefore have an increased risk of low back pain due to this whole body vibration (Palmer et al, 2000). In addition it has been noted that the number of motor vehicle accidents will also increase the risk of low back pain due to mechanical injury (Cassidy et al, 2003). Low back pain could therefore interfere with their ability to carry out their duties, affect their attitude towards patients and colleagues, impact on the level of patient care required of them, and result in increased absenteeism. Persistence of chronic low back with the inability to perform their duties may result in the need to find alternative employment or result in premature dismissal. The objectives of this study were: to determine if emergency medical personnel have a higher risk factor for the development of low back pain due to their occupation than the general population; as well as determine if an increase in the number of years working in the field (i.e. years of exposure) leads to an increased incidence and / or prevalence of low back pain.

Thesis (M.Tech.: Environmental Health)-Dept. ofEnvironmental Health, Durban Institute of Technology, 2005 xv, 144 leaves ; 30 cm / Motivation: Lower back pain (LBP) has been found to affect workers and often result in higher costs to industry than any other musculoskeletal disorder. Traditionally, the most widely investigated risk factors for LBP have been biomechanical demands of the job. By examining LBP, both its prevalence and distribution, it becomes possible to focus on contributory risk factors that bring on its onset. Aim: To identify the selected risk factors associated with prevalence of LBP amongst refuse truck drivers in the eThekwini Municipality, and to evaluate the relationship between the selected risk factors and the prevalence of LBP.

The importance ascribed by a nation to the subject of occupational safety and health is reflective in the growth, sustainability and the national development of an economy. Besides the economic benefits stood to be derived from an occupational safety and health structure that is constantly nurtured, there is also the human rights issue. Less industrialised nations still grapple with fundamental challenges brought about by occupational health and safety, challenges which more advanced nations seem to effortlessly address. Nigeria falls into the former category, hence, the interest of this thesis. The knowledge of this menace has been in the consciousness of stakeholders in Nigeria particularly in the recent past years. However, no significant action has been taken to alleviate the situation. There are instruments that deal with the subject of occupational health and safety but they all seem to have their attendant issues which make them either inoperable or of insignificant benefit to the situation of workers in Nigeria. The tardy attitude of the Nigerian Law makers also does not help the situation. This thesis is therefore of the view that until the period the Nigerian Government is able to get its bearing right in designing a suitable piece of legislation that shall address the challenges caused by occupational health and safety, it is possible to seek an alternative approach that shall serve as a safety net towards the protection of workers particularly those that are most vulnerable. This alternative approach that the thesis proposes is the National Industrial Court of Nigeria (NICN), a Court that recently acquired the status of a superior court of record and conferred with extensive Constitutional powers over occupational safety and health matters amongst others. It is the anticipation of this thesis that the Court shall make a positive impact where legislation had failed to succeed in its bidding.

No description available.

Occupational asthma affects a variety of industry sectors, including agricultural and manufacturing. Currently, asthma pharmaceuticals are delivered via an inhaler and deposited in the respiratory system. The effectiveness of the medication depends partially on where the particle deposits in the lung. The specific aims of this research were to (1) develop a system to measure hygroscopic particle growth under different environmental conditions; (2) determine the accuracy of a hygroscopic growth model during the growth phase of salt particles; and (3) determine whether the large-diameter particles of an aerosol, those that will most likely deposit in the upper airways, can be separated from the smaller particles. Aim 1: A system was developed that satisfied the design criteria to measure particle growth within fractions of a second. The particles growth was measured every 0.03 seconds and had a relative humidity that only varied by a maximum of 1.3% over a 30 second trial. Aim 2: The next step in the research was to determine how well the model compares to reality in the initial growth phase. The model that included the initial growth rate as a saturated solution had a lower root mean square of error (RMSE) than the model that did not include a maximum saturation value. The maximum reduction in RMSE was 0.254. Aim 3: The analysis of a virtual impactor was conducted to see if aerosolized particles can be size separated at a cut point of 2.5 μm. The virtual impactor was designed to have small particles exit the device in one airflow and the large particles exit in a different airflow. Multiple trials were conducted however, there were only two trials that had any size separation between the two exiting flows. From these results, it was determined that large-diameter particles cannot be separated from smaller particles while remaining aerosolized. The cut-point was 2.3 μm, the small particles were split at 50% through both flows, and the flow that was supposed to contain 100% of all of the large particles only contained a maximum of 70%.

Tractors and other self-propelled farm equipment, such as combines, sprayers, and towed grain carts, are often used on public roadways as the primary means for traveling from homestead to homestead or from homestead to a distributer. Increased roadway exposure has led to a growing concern for crashes involving farm equipment on the public roadway. A handful of studies exist examining public roadway crashes involving farm equipment using crash data, but none thus far have evaluated road segment data to identify road-specific risk factors. The objective of this study is to identify if roadway characteristics (traffic density, speed limit, road type, surface type, road width, and shoulder width) affect the risk of a crash involving farm equipment on Iowa public roadways. A retrospective cohort study of Iowa roads was conducted to identify the types of roads that are at an increased risk of having a farm-equipment crash on them. Crash data from the Iowa Department of Transportation (to identify crashes) were spatial linked to Iowa roadway data using Geographic Information Systems (GIS). Logistic regression was used to calculate ORs and 95% CL. Out of 319,705 road segments in Iowa, 0.4% segments (n=1,337) had a farm equipment crash from 2005-2011. The odds of having a farm equipment crash were significantly higher for road segments with increased traffic density and speed limit. Roads with an average daily traffic volume of at least 1,251 vehicles were at a 5.53 times greater odds of having a crash than roads with a daily traffic volume between 0-30 vehicles. (CI: 3.90-7.83). Roads with a posted speed limit between 50mph and 60mph were at a 4.88 times greater odds of having a crash than roads with a posted speed limit of 30mph or less. (CI: 3.85-6.20). Specific roadway characteristics such as roadway and shoulder width were also associated with the risk of a crash. For every 5 foot increase in road width, the odds for a crash decreased by 6 percent (CI: 0.89-0.99) and for every 5 foot increase in shoulder width, the odds of a crash decreased by 8 percent. (CI: 0.86-0.98). Although not statically significant, unpaved roads increased the odds of a crash by 17 percent. (CI: 0.91-1.50) Lastly, it was found that Farm to Market routes increased the odds of a crash by two fold compared to local roads (which make up roughly 67 percent of Iowa public roads). (CI: 1.72-2.43) When the same model was stratified by rurality (urban/rural), it was found that high traffic density leads to a higher risk of a crash in rural areas. Iowa routes and Farm to Market routes had a greater odds of a crash in urban than rural areas, and road and shoulder width were more protective in rural than urban areas. When only using roads with a crash involving an injury versus all other roads as the outcome, Iowa routes and roads with increased speed limits had higher odds for an injury-involved crash, while increased road width were more protective against crashes involving injuries. Findings from the study suggest that several roadway characteristics were associated with farm-equipment crashes. Through administrative and engineering controls, the six static explanatory variables used in this study may be modified to decrease the risk of a farm equipment crash. Speed limit can be modified through administrative controls while traffic density, road and shoulder width, road type, and surface type can be modified through engineering controls. Results from this study provide information that will aid policy-makers in developing safer roads for farm equipment.

Although the production of polychlorinated biphenyl (PCB) technical mixtures has been banned in the U.S. since the 70’s, they remain ubiquitous in the environment, particularly in indoor and ambient air. Due to the presence of PCB’s in air, inhalation is a significant route of exposure. PCBs released from various building materials have been shown to contaminate the indoor air in homes and schools. In the AESOP Study, an epidemiologic study of PCB exposures among school children and their mothers, PCB28 was found in the serum of over 20% of participants. Data are lacking on the absorption, distribution, metabolism, and excretion (ADME) of inhaled PCBs and on the biological fate and dose-specific toxicological endpoints. In order to inform toxicokinetic modeling for risk-assessment, we are conducting ADME toxicological studies with lung exposure to a representative trichlorobiphenyl, and evaluating the uptake from the lung and the distribution, metabolism, and excretion. Male Sprague-Dawley rats were exposed to [14C]PCB28 via intratracheal instillation at two different doses (42 µg/rat and 4.2 µg/rat). Digestive matter from five separate compartments of the gastrointestinal tract and thirty-six tissue types were excised and measured by scintillation counting. Exhaled air and excreta were also collected and analyzed. Measurements for the high dose were made at 12, 25, 50, 100, 200, 400, 720, and 1440 min, and for the low dose at 2, 12, 50, 200, and 720 min post-exposure. Data show that pulmonary uptake exceeded 99% in both doses. [14C]PCB28 entered the blood stream and distributed quickly to all tissues within minutes of dosing. In the high dose, the majority of radioactivity initially went to the muscle and liver, while in the low dose [14C]PCB28 initially distributed to the muscle, esophagus, and trachea, before being redistributed to the skin and adipose tissue, where it accumulated in both doses. In most tissues, elimination was biphasic, consisting of an initial fast phase with a half-life (t1/2) of 7-93 min (high dose) and t1/2 of 6-60 min (low dose), followed by a slower phase with t1/2 of 5-18 hours (high dose) and t1/2 of 3-18 hours (low dose). The metabolism of PCB28 was not extensive, with the parent compound as the major component in liver, kidney, serum, and adipose tissue. Excretion via urine and feces was limited, with 92% (high dose) and 88% (low dose) of radioactivity remaining in the tissues by the end of the time course, primarily in skin and adipose tissue. Low urinary concentration relative to serum, suggested that parent PCB28 in serum would serve as an accurate biomarker for assessment of exposure to inhaled trichlorobiphenyls. The time course and tissue distribution is comparable to [14C]PCB11, while metabolism and excretion of [14C]PCB28 is much less extensive.

This study looked at the effect relative humidity had on respirator performance.

Pesticides are toxic by nature and they pose a serious threat to populations in agricultural communities, particularly to children, and farmers in low-income countries. Children living in agricultural communities may face a higher risk from pesticide exposure in the home environment than children in the general population. Farmers in low-income countries may also have higher risks from increased pesticide exposure due to the use of highly toxic pesticides that are banned in other countries and to unsafe practices and behaviors while handling pesticides. There is a growing body of literature that suggests pesticides, specifically organophosphorus pesticides (OPs), cause neurobehavioral impairment in children and adults. In a fruit orchard community in the U.S. Pacific Northwest, dust was collected from households and analyzed for four types of OPs. Various factors such as housing characteristics and resident behaviors were evaluated to examine their relationships with the OP concentrations in the home dust. School-aged children completed a battery of neurobehavioral tests at two time points, one year apart. The relationship between pesticide exposure, measured with parents’ occupations and a summary OP concentration, and neurobehavioral performance was examined. A cross-sectional study was carried out in The Gambia to identify rural residents’ knowledge about pesticide hazards and practices while handling pesticides. Relationships between participants’ knowledge, characteristics, and practices were examined. Occupational exposure scores were developed to quantify participants’ chronic pesticide exposures using the study’s questionnaire. In addition, participants provided information on neurological symptoms associated with pesticide use and a neurobehavioral test battery was administered to assess cognitive function. The relationships between occupational exposure scores and neurological symptoms and neurobehavioral performance were examined. In the orchard community, OP detection frequencies and concentrations were higher in agricultural households compared to non-agricultural households. Significant associations were found between higher OP concentrations in dust and the following: (1) homes with a parent working in an agricultural field and/or orchard, (2) homes with ≥ 2 agricultural workers living in the home, and (3) homes located in close proximity to an agricultural field or orchard. Having air conditioning in the home had a protective effect on OP concentrations. Results suggested that deficits in learning, or less improvement, on the neurobehavioral tests from the first visit to the second visit were found in agricultural children compared to non-agricultural children. In The Gambia, the majority of participants reported risky practices while handling pesticides such as: not wearing any protective clothing or equipment; mixing with bare hands; applying with their bare hands, plastic bags, or leaves; storing pesticides in the home; inadequately disposing of empty pesticide containers; and wearing shoes into the home after working with pesticides. They also reported having concerns about the adverse effects of pesticides on their health. Participants having had farm or pesticide safety training reported having less risky pesticide handling practices and behaviors. Participants with high occupational exposure scores experienced more symptoms and had worse performance on several of the neurobehavioral tests, including tests of motor function and dexterity, compared to participants with low exposure scores. Results from these studies suggest neurobehavioral impairments were found in participants with higher pesticide exposures compared to participants with lower exposures in the two populations. Further research is needed to identify successful strategies for reducing pesticide exposure in the home environment and while handling pesticides.