3 resultados para clean water
em DigitalCommons@The Texas Medical Center
Resumo:
In the last two decades, the significance of lead has been addressed in a number of environmental regulations at the national and state levels. This project investigated the environmental regulations (Clean Air Act and Amendments, 1970-1990 and Clean Water Act of 1977) and their cumulative effects on lead in ambient air and water in the state of Texas. For this purpose, historical records from the Texas Water Development Board, Texas Natural Resources Conservation Commission, and the United States Geological Survey have been assembled and analyzed for temporal and spatial trends. These trends might correspond to the phase out of lead in gasoline and other regulations.^ This study concluded that there is a significant correlation (p $\leq$.001) between environmental regulations of lead in gasoline and the concentration of lead in ambient air. Lead concentrations in ambient air have been reduced by over 90 percent in the past twenty years. An overall significant difference (p $\leq$.001) was found in mean (94, 15 respectively) lead concentrations in surface water between two time periods, one at the beginning of the twenty year period and one at the end of the study period. There has been an overall reduction of lead concentrations in surface water in Texas of approximately 84 percent. However, this reduction cannot be statistically associated with any one regulation. Groundwater data could not be analyzed for lead concentrations because of limitations of reporting data as "less than". Approximately two percent of the groundwater data was analyzed by Oneway ANOVA and no significant difference was found between the means (18, 19 respectively) of two time periods, 1977-1979 and 1988-1990. This data is consistent with the regulations having a contributory affect on declining concentrations, but other factors cannot be ruled out as having added to these declines. This study can also serve as a starting point for a more in-depth study of environmental regulations and their impact on the environment. ^
Resumo:
NORM (Naturally Occurring Radioactive Material) Waste Policies for the nation's oil and gas producing states have been in existence since the 1980's, when Louisiana was the first state to develop a NORM regulatory program in 1989. Since that time, expectations for NORM Waste Policies have evolved, as Health, Safety, Environment, and Social responsibility (HSE & SR) grows increasingly important to the public. Therefore, the oil and gas industry's safety and environmental performance record will face challenges in the future, about its best practices for managing the co-production of NORM wastes. ^ Within the United States, NORM is not federally regulated. The U.S. EPA claims it regulates NORM under CERCLA (superfund) and the Clean Water Act. Though, there are no universally applicable regulations for radium-based NORM waste. Therefore, individual states have taken responsibility for developing NORM regulatory programs, because of the potential radiological risk it can pose to man (bone and lung cancer) and his environment. This has led to inconsistencies in NORM Waste Policies as well as a NORM management gap in both state and federal regulatory structures. ^ Fourteen different NORM regulations and guidelines were compared between Louisiana and Texas, the nation's top two petroleum producing states. Louisiana is the country's top crude oil producer when production from its Federal offshore waters are included, and fourth in crude oil production, behind Texas, Alaska, and California when Federal offshore areas are excluded. Louisiana produces more petroleum products than any state but Texas. For these reasons, a comparative analysis between Louisiana and Texas was undertaken to identify differences in their NORM regulations and guidelines for managing, handling and disposing NORM wastes. Moreover, this analysis was undertaken because Texas is the most explored and drilled worldwide and yet appears to lag behind its neighboring state in terms of its NORM Waste Policy and developing an industry standard for handling, managing and disposing NORM. As a result of this analysis, fourteen recommendations were identified.^
Resumo:
Background. Nosocomial invasive aspergillosis (a highly fatal disease) is an increasing problem for immunocompromised patients. Aspergillus spp. can be transmitted via air (most commonly) and by water. ^ The hypothesis for this prospective study was that there is an association between patient occupancy, housekeeping practices, patients, visitors, and Aspergillus spp. loading. Rooms were sampled as not terminally cleaned (dirty) and terminally cleaned (clean). The secondary hypothesis was that Aspergillus spp. positive samples collected from more than one sampling location within the same patient room represent the same isolate. ^ Methods. Between April and October 2004, 2873 environmental samples (713 air, 607 water, 1256 surface and 297 spore traps) were collected in and around 209 “clean” and “dirty” patient rooms in a large cancer center hospital. Water sources included aerosolized water from patient room showerheads, sinks, drains, and toilets. Bioaerosol samples were from the patient room and from the running shower, flushing toilet, and outside the building. The surface samples included sink and shower drains, showerheads, and air grills. Aspergillus spp. positive samples were also sent for PCR, molecular typing (n = 89). ^ Results. All water samples were negative for Aspergillus spp. There were a total of 130 positive culturable samples (5.1%). The predominant species found was Aspergillus niger. Of the positive culturable samples, 106 (14.9%) were air and 24 (3.8%) were surface. There were 147 spore trap samples, and 49.5% were positive for Aspergillus/Penicillum spp. Of the culturable positive samples sent for PCR, 16 were indistinguishable matches. There was no significant relationship between air and water samples and positive samples from the same room. ^ Conclusion. Primarily patients, visitors and staff bring the Aspergillus spp. into the hospital. The high number of A. niger samples suggests the spores are entering the hospital from outdoors. Eliminating the materials brought to the patient floors from the outside, requiring employees, staff, and visitors to wear cover up over their street clothes, and improved cleaning procedures could further reduce positive samples. Mold strains change frequently; it is probably more significant to understand pathogenicity of viable spores than to commit resources on molecular strain testing on environmental samples alone. ^