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171.

Background, aims, and scope

Formaldehyde (FA) is a harmful chemical, which is classified as carcinogenic to humans (Group 1) by the International Agency for Research on Cancer. Solutions of FA that are used to preserve cadavers in research and education morphological institutes represent a risk to occupational health of professionals and students. During the dissection of cadavers in the anatomy laboratories, FA vapors are emitted, resulting in the exposure of students and their instructors to elevated levels of FA. The World Health Organization recommends an air quality guideline value of 0.1 mg m?3 for exposure to FA. The limit of occupational exposure adopted by the Brazilian legislation (2.3 mg m?3) is markedly higher than those adopted by institutions of other countries around the world. The purpose of this study was to determine the levels of personal exposure and the area concentration of FA in the morphology department of the Federal Fluminense University, Brazil, and investigate and compare the relationship between them.

Methods

Four rooms distributed in the three floors of the Morphology Department were evaluated: the embalming laboratory, the anatomy laboratories, the corridor of the teachers?? rooms, and the entrance hall. Thirty-six samples in total were collected in the second semester of 2010 and first semester of 2011. The air sampling and FA analysis were performed according to the EPA TO-11A Protocol, using a diffusive sampling device for carbonyl compounds. Personal samples were collected from monitors using a sampling device pinned on each person??s lapel. The samples were analyzed using rapid resolution liquid chromatography with UV-DAD detection at 360 nm.

Results and discussion

The concentrations of FA ranged from 0.20 and 0.18 mg m?3 in the corridor between the teachers?? rooms, 0.03 to 0.37 mg m?3 in the entrance hall, 0.22 to 2.07 mg m?3 in the anatomy laboratory, 2.21 to 2.52 mg m?3, in the embalming room. The levels found in the corridor between the teachers?? rooms and in the entrance hall were lower than in other compartments because of their large distances to the sources of FA and better ventilation. The other rooms presented higher levels of FA because of the activities carried there (embalming and dissection procedures). Even in the rooms that showed the lowest levels of FA, the values found were higher than those established by all international guideline limits, except the Brazilian legislation limit, although, the concentration level in the embalming room was even greater than the Brazilian guideline. These concentrations are 100?C1,000-fold higher than those reported in an FA outdoor study. The exposure levels of monitors and students ranged from 1.89 to 4.82 mg m?3, indicating that current practices at the Morphology Department at the university would represent a health risk. The simultaneous monitoring of area concentrations and personal exposure showed that the characteristics of classes and of cadavers?? parts, the number of students in the room and even the activities of the monitors influence the FA concentrations.

Conclusion

This study revealed that the concentration of FA was low in the ventilated areas of the Morphology Department, and that the personal exposure when the person was close to the cadavers during the dissection procedure was higher than the mean FA concentration. This should be considered in the risk assessment of FA during these activities without effective protection equipment. It is suggested that the Brazilian legislation of exposure to formaldehyde requires an urgent update considering international legislation.  相似文献   
172.
The production of solid organic waste (SOW) such as sewage sludge (SS) or municipal solid waste (MSW) has been continuously increasing in Europe since the beginning of the 1990'. Today, the European Union encourages the stabilization of these wastes using biologic processes such as anaerobic digestion and/or composting to produce bio-energy and organic fertilizers. However, the design and management of such biologic processes require knowledge about the quantity and quality of the organic matter (OM) contained in the SOW. The current methods to characterize SOW are tedious, time-consuming and often insufficiently informative. In this paper, we assess the potential of solid-phase fluorescence (SPF) spectroscopy to quickly provide a relevant characterization of SOW. First, we tested well known model compounds (tryptophan, bovine serum albumin, lignin and humic acid) and biologic matrix (Escherichia coli) in three dimensional solid-phase fluorescence (3D-SPF) spectroscopy. We recorded fluorescence spectra from proteinaceous samples but we could not record the fluorescence emitted by lignin and humic acid powders. For SOW samples, fluorescence spectra were successfully recorded for MSW and most of its sub-components (foods, cardboard) but impossible for SS, sludge compost (SC) and ligno-cellulosic wastes. Based on visual observations and additional assays, we concluded that the presence of highly light-absorptive chemical structures in such dark-colored samples was responsible for this limitation. For such samples, i.e. lignin, humic acid, SS, SC and ligno-cellulosic wastes, we show that laser induced fluorescence (LIF) spectroscopy enables the acquisition of 2D fluorescence spectra.  相似文献   
173.
Fe-Co3O4 thin film with different amounts of Fe have been used for the electro-oxidation of phenol in alkaline medium at room temperature. The electrodes were prepared by coating stainless steel supports with successive layers of the oxides, obtained by thermal decomposition at 673 K. The electrolysis was carried out at constant potential and the phenol disappearance, during the electrolysis, was monitored by UV-Vis absorbance measurements between 250 and 500 nm. After 3 h of electrolysis, the intermediates were identified by comparing the HPLC data and UV-Vis spectra to those from pure standards. The results indicate that the same oxidation products are formed on the different prepared electrodes, namely the decomposition products of phenol such as benzoquinone, hydroquinone and cathecol in basic medium. Simulated results show clearly the decrease of the amount of phenolic species with the electrolysis time. An enhancement of the phenol removal is observed with the presence of iron in the oxide. Under the operating conditions, around 30% of the initial phenol has been removed at ca. 3 h and the complete degradation is obtained after 54 h of electrolysis, when Fe-Co3O4 thin film with 10% of Fe is used as anode.  相似文献   
174.
INTRODUCTION: Flowing of the acid mine drainage may contaminate the adjacent water bodies causing substantial changes in the aquatic ecosystem. This aspect is the most relevant problem in the southern of Santa Catarina once the contaminated areas are inserted in the watershed of the Araranguá, Urussanga, and Tubar?o rivers, increasing the need for recovery studies. These areas are between Criciúma, I?ara, Urussanga, Siderópolis, Lauro Müller, Orleans, and Alfredo Wagner towns where a conservation unit exist called the Environmental Preservation Area of Baleia Franca. Aiming to compare the kinetics of the ash derived from burning coal and to neutralize acid mine drainage, different neutralizer, limestone, fly, and bottom ash, was mounted on a pilot scale experiment. DISCUSSION: The transport parameters showed the same order of infiltration and dispersion: fly ash < bottom ash < limestone. The order of measured alkalinity was: limestone < fly ash < bottom ash, with pH values of 9.34, 12.07, and 12.25, respectively. The limestone kinetics of acidic drainage neutralization was first order with reaction rate constant k?=?0.0963 min(-1), bottom ash was 3/4 with k?=?0.0723 mol(1/4) L(-1/4) min(-1), and the fly ash had higher order kinetics, 4/3, with reaction rate constant k?=?27.122 L(1/3) mol(-1/3) min(-1). However, by mathematical modeling, it was found that due to a combination of transport and kinetics, only limestone treatment reached a pH above 6 within 5 years, corresponding to the ideal as planned.  相似文献   
175.
This study investigated whether perinatal exposure to diuron [3-(3,4-dichlorophenyl)-1-1-dimethylurea] might exert adverse effects on rat lymphoid organs. Pregnant Sprague-Dawley (SD) rats were exposed to diuron at 500, 750 or 1250 ppm in the diet from gestational days (GD) 12–21 and during lactation. At postnatal day (PND) 42, male pups were euthanized and thymus, spleen, mesenteric lymph node and femur were collected for histopathological analysis. Food consumption and body weight gain were significantly reduced in dams exposed to 1250 ppm during gestation period. Also, Diuron at 750 and 1250 ppm produced: (1) increased relative spleen weight associated histologically with severe congestion in red pulp, (2) enhanced extramedullary hematopoiesis and hemosiderosis as well as (3) depletion of lymphoid follicles in white pulp. Flow cytometric analysis revealed a significant reduction in B lymphocytes (CD45RA+) in male pups but T lymphocytes (CD4+, CD8+ and CD4+/CD8+) were not markedly affected. Thus, data suggest that Diuron-induced maternal toxicity in dams exposed to high dose and perinatal exposure to this herbicide produced spleen toxicity as evidenced by a reduction in B lymphocyte number in male SD pups.  相似文献   
176.
177.
Financial barriers are often cited as the principle impediment to the adoption of energy efficiency measures. Since 1976, the US Department of Energy's Weatherisation Assistance Programme (WAP) has provided state block grants for no-cost, low-income energy efficiency retrofits. Yet, millions of low-income American households lack affordable, reliable, and efficient energy access. The American Recovery and Reinvestment Act of 2009 boosted WAP's annual appropriation from $230 million to $5 billion, requiring states to explore innovate approaches to quickly increasing programme participation. Community-based energy programmes have shown success for overcoming various barriers and increasing participation in the adoption of energy technologies. This case study explores a community-based approach to scaling WAP-funded energy efficiency retrofits in a cluster of five urban, low-income, majority African-American neighbourhoods, known as the Green Impact Zone (GIZ), in Kansas City, Missouri. Findings from interviews with GIZ stakeholders suggest that local context is important to how energy efficiency participation barriers manifest. The targeted, community-based approach to WAP created institutional capabilities for increased recognition of participation challenges and facilitated opportunities for alternative solutions that may otherwise have been overlooked under the standard self-referral implementation of WAP. Lastly, effective implementation of WAP required policy workarounds that recognised the unique characteristics and needs of the target community.  相似文献   
178.
Using mussels as monitoring tools we measured water quality in Sydney Harbour during a large scale, multi-year remediation project of the Sydney Tar Ponds (STPs); one of Canada's most contaminated sites. Chemical contaminants were measured in blue mussels (Mytilus edulis) in Sydney Harbour, which were used as monitoring tools to assess the spatio-temporal distribution of polycyclic aromatic hydrocarbons (PAHs); polychlorinated biphenyls (PCBs); metals (As, Cd, Cu, Hg, Pb, Zn) and lipid content during baseline and 3 years of remediation. The overall spatio-temporal distribution of chemicals in mussels was also compared to contaminants in other marine indicators (e.g., sediment, water and crab tissue). Measured metal concentrations in mussels showed some minor temporal variability (4 years), but these did not appear to be directly related to remediation activities, with the highest concentrations of As, Hg and Zn measured at reference stations. Most measured contaminants showed stable or potentially decreasing concentrations during the study, except Pb and Zn. Individual PAH compounds were mostly undetected during baseline and remediation, except for fluoranthene and pyrene. Concentrations of fluoranthene in mussels and deep water samples were moderately related. Generally, PCBs were undetected (<0.05 μg g?1), except during year 2 remediation at some near-field stations. Contaminants measured during this study were at much lower concentrations than previously reported in other studies of mussels in Sydney Harbour and eastern Canada. This is likely due to the ongoing natural recovery of Sydney Harbour and to a lesser extent because of the environmental mitigation protection measures implemented during remediation activities at the STPs. The lack of detection of most individual PAHs and PCBs, plus relatively low bio-accumulation of metals observed during baseline and remediation attest to the effectiveness of using mussels as monitoring tools for environmental quality.  相似文献   
179.
In this study, particulate matter (PM) were characterized from a place impacted by heavy-duty vehicles (Bus Station) fuelled with diesel/biodiesel fuel blend (B3) in the city of Londrina, Brazil. Sixteen priority polycyclic aromatic hydrocarbons (PAH) concentrations were analyzed in the samples by their association with atmospheric PM, mass size distributions and major ions (fluorite, chloride, bromide, nitrate, phosphate, sulfate, nitrite, oxalate; fumarate, formate, succinate and acetate; lithium, sodium, potassium, magnesium, calcium and ammonium). Results indicate that major ions represented 21.2% particulate matter mass. Nitrate, sulfate, and ammonium, respectively, presented the highest concentration levels, indicating that biodiesel may also be a significant source for these ions, especially nitrate. Dibenzo[a,h]anthracene and indeno[1,2,3,-cd]pyrene were the main PAH found, and a higher fraction of PAH particles was found in diameters lower than 0.25 μm in Londrina bus station. The fine and ultrafine particles were dominant among the PM evaluated, suggesting that biodiesel decreases the total PAH emission. However, it does also increase the fraction of fine and ultrafine particles when compared to diesel.  相似文献   
180.
For many millennia humans and reptiles have interacted, but the attitude of humans towards these animals has depended on culture, environment, and personal experience. At least 719 reptile species are known to occur in Brazil and about 11% of this fauna has been exploited for many different purposes, including bushmeat, leather, ornamental and magic/religious uses, and as folk medicines. Brazil can therefore serve as an interesting case study for better understanding reptile use by human societies, and the present paper catalogues some of the reptile species being used in Brazil and discusses implications for their conservation. A literature review indicated that 81 reptile species are culturally important in this country, with 47 (58%) species having multiple uses, 54 being used for medicinal purposes, 38 as food, 28 for ornamental or decorative purposes, 20 used in magic/religious practices, 18 as pets, and 40 are commonly killed when they come into contact with humans. Regarding their conservation status, 30 (37.5%) are included on State's Red List, Brazilian Red List or the IUCN Red List. There are many forms of interaction between reptiles and humans in Brazil-although most of them are quite negative in terms of wildlife conservation-which reinforces the importance of understanding such uses and interactions in the context of protecting reptiles in Brazil. A better understanding of the cultural, social, and traditional roles of these reptiles is fundamental to establishing management plans for their sustainable use.  相似文献   
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