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Assessment of Total Mercury in Hair, Urine and Fingernails of Small–Scale Gold Miners in the Amansie West District, Ghana Full text
2019
Edward Ebow Kwaansa-Ansah | Edward Kwaku Armah | Francis Opoku
Background. Mercury (Hg) is a heavy metal that can cause several adverse health effects based on its form (organic, inorganic or elemental), duration and pathway of exposure. Measurement of mercury present in human biological media is often used to assess human exposure to mercury at mining sites. Objectives. The aim of the present study was to measure the concentrations of total mercury in urine, hair, and fingernails of miners and inhabitants of Amansie West District, Ghana. Methods. Concentrations of total mercury were measured in sixty–eight miners and twelve non–miners in the study area using cold vapor atomic absorption spectrophotometry with an automatic mercury analyzer (HG 5000). Results. Total mercury in nails and hair of smelter miners was 3.32 ± 0.36 and 6.59 ± 0.01 μg/g, respectively. Total mercury concentrations in hair samples obtained from smelter miners were above the 1 μg/g guideline set by the United States Environmental Protection Agency (USEPA). Moreover, the total mercury concentration in urine samples was 6.97 ± 0.06 μg/L, far below the >25 μg/L level considered to be a high level of mercury contamination. The total mercury accrued by the individuals was not dependent on age, but was positively associated with duration of stay. Conclusions. Based on the total mercury (THg) levels analyzed in the biological media, artisanal gold mining activities in Amansie West District are on the increase with a potential risk of developing chronic effects. However, the majority of the population, particularly those engaged in artisanal small–scale gold mining, are unmindful of the hazards posed by the use of mercury in mining operations. The results showed that THg in urine, hair, and fingernails more efficiently distinguished mercury exposure in people close to mining and Hg pollution sources than in people living far from the mining sites. Further education on cleaner artisanal gold mining processes could help to minimize the impact of mercury use and exposure on human health and the environment. Participant Consent. Obtained Ethics Approval. This study was approved by the Ghana Environmental Protection Agency and the Ministry of Local Government and Rural Development in Manso Nkwanta. Competing Interests. The authors declare no competing financial interests.
Show more [+] Less [-]Effect of Polycyclic Aromatic Hydrocarbons Exposure on Sperm DNA in Idiopathic Male Infertility Full text
2019
Aziza A. Saad | Tarek Hussein | Amany El-Sikaily | Mohamed A. Abdel-Mohsen | El-Hassan Mokhamer | Amany I. Youssef | Jihan Mohammed
Background. Biological mechanisms contribute to the relationship between polycyclic aromatic hydrocarbon (PAH) exposure and infertility in males by altering semen quality. Objectives. The aim of the present study was to evaluate the impact of PAHs on male infertility using the sperm chromatin dispersion test (Halo sperm assay). Methods. Sixty-six (66) infertile males under 45 years of age were examined for the determination of urinary metabolite and oxidative stress by measuring lipid peroxidation and antioxidant activity of glutathione and glutathione-s-transferase, as well as hormonal activity of follicle stimulating hormone (FSH), testosterone and prolactin and semen quality. Results. There was an increased level of urinary metabolite of 1-hydroxy pyrene, 1-hydroxy naphthalene and 2-hydroxy naphthalene in the urine of the infertile group. In addition, elevated concentrations of malondialdehyde coincided with a decreased level of antioxidants, leading to oxidative stress in the infertile group. Semen samples showed 30% sperm deoxyribonucleic acid (DNA) fragmentation. Conclusions. The data provide strong evidence of a statistical threshold for semen samples containing 30% sperm DNA fragmentation resulting in a reduced level of pregnancy success. Participant consent. Obtained Ethics Approval. Study approval was given by the ethics committee of Alexandria University (United States Department of Health and Human Services, institutional review board registration (IRB), IORG0008812 Medical Research Institute, expires 4/8/2019, OMB No: 0990-0279). Competing Interests. The authors declare no competing financial interests.
Show more [+] Less [-]Neurobehavioral Effects of Organic Solvents Exposure Among Wood Furniture Makers in Ile-Ife, Osun State, Southwestern Nigeria Full text
2019
Patrick Ayodeji Akinyemi | Caleb Aderemi Adegbenro | Temitope Olumuyiwa Ojo | Olanrewaju Elugbaju
Background. Furniture making industries are small scale businesses that commonly use organic solvents. There has been minimal focus on the health effects of this chemical hazard on the nervous system among furniture makers in Nigeria. Objectives. The present study aimed to assess the association between organic solvents exposure and neurobehavioral status of furniture makers, using electronic technicians as a comparison group. Methods. A comparative cross-sectional study design was employed. A sample size of 108 was calculated for each group. A semi-structured interviewer-administered questionnaire was used to obtain data on the socio-demographic variables and use of personal protective equipment (PPE). A proforma was developed to collect neurobehavioral assessment data. A checklist was used to assess the furniture makers' workshops. Air was sampled from all of the workshops in both the study and comparison groups to determine the concentration of total volatile organic compounds (TVOCs). Results. The use of PPE was poor in both the study and comparison groups, with no significant difference between them (34.4% and 37.7% respectively). Total volatile organic compound and formaldehyde (HCHO) concentrations were significantly higher at the furniture makers' workshops compared with electronic technicians (p<0.001) for both chemicals. The 8-hour time-weighted average of TVOC was also higher in the furniture makers' workshops (4.4±0.6 mg/m3) compared with the control group (0.3±0.3 mg/m3). The neurobehavioral symptoms score was significantly higher among the study group relative to the comparison group (p<0.001). There was a significant difference in the outcome of the auditory verbal learning test, total recall (p=0.005), and delayed recall (p=0.003). There was no significant association between solvent exposure index and findings from the simple reaction time test Conclusions. Poor compliance with the use of PPE among furniture makers may increase their exposure to organic solvents. There were more neurobehavioral changes in the furniture makers with a higher exposure index. Measures are needed to educate artisans about workrelated chemical hazards and ensure compliance with basic occupational safety and hygiene standards. Participant Consent. Obtained Ethics Approval. Ethics approval was obtained from the Health Research and Ethics Committee of the Institute of Public Health, Obafemi Awolowo University (IPH/OAU/12/1049). Competing Interests. The authors declare no competing financial interests.
Show more [+] Less [-]Pollution and Perceptions of Lead in Automobile Repair Shops in Dhaka, Bangladesh Full text
2019
Md. Kawser Uddin | Ahmad Kamruzzaman Majumder | Md. Sahadat Hossain | Abdullah Al Nayeem
Background. Lead acid batteries are widely used, dependable, and inexpensive. Lead from these batteries can contaminate the surrounding ecosystem due to improper disposal and contribute to lead poisoning. Lead poisoning is an important public health issue that can cause adverse human health impacts. Objectives. The present study aimed to assess exposure to lead released from automobile repair shops handling lead acid batteries in the city of Dhaka, Bangladesh, as well as shop owner and worker perceptions of lead pollution. Methods. Ten dust samples were collected for atomic absorption spectrophotometer analysis to determine the concentration of lead. In addition, a questionnaire survey (N=75) was conducted to determine the level of knowledge of lead exposure and associated risks. Results. Lead contamination was found in all dust samples, with lead concentrations ranging from 11.40 ppm to greater than 1000 ppm. In addition, 80% of respondents did not have any knowledge about the harmful effects of lead pollution. Conclusions. The present study suggests the importance of defining permissible air lead levels and improving worker education on lead pollution. Ethics Approval. The study was approved by the Ethics Committee of the Department of Environmental Science, Stamford University, Bangladesh. Competing Interests. The authors declare no competing financial interests.
Show more [+] Less [-]Comparison of the Contaminants in the Wastewater Produced in the Ex Situ Underground Ortho- and Meta-Lignite Gasification Full text
2019
Kapusta, Krzysztof | Stańczyk, Krzysztof | Wiatowski, Marian
This work comprises results of the laboratory tests on formation and potential release of contaminants from underground gasification of lignites. Four large scale and multi-day trials were carried out using ex-situ gasification facilities. Two different kinds of lignite were tested, i.e. Velenje lignite (Slovenia) and Oltenia lignite (Romania). Gasification tests were conducted in the artificial coal seams under two distinct pressure regimes—atmospheric and high pressure regime (35 bar and 10 bar for the Velenje and Oltenia samples respectively). The UCG wastewater samples were periodically collected from the gas purification module to measure the rate of the wastewater and contaminants production at each phase of the experiment and to assess the effect of gasification pressure and lignite physicochemical properties. The group of target contaminants included: phenols, aromatic hydrocarbons, and some non-specific water parameters. The effect of gasification pressure was confirmed, especially for BTEX and phenols and significant drops in the contents of these compounds were observed at elevated pressures. The effect of pressure was more pronounced for the geologically older coal (Velenje), i.e. drop in the average concentrations from 1994 μg/l (atmospheric) to 804 μg/l (35 bar) and from 733 mg/l (atmospheric) to 17 mg/l (35 bar) for BTEX and total phenols, respectively. The differences in the macromolecular structure and ash content of the both coals were found to be the main reason behind the differences in the contents of organic and inorganic species respectively. The study also shown that composition of UCG wastewaters significantly varied over the time of the particular experiments, which reflected changes in the gasification thermodynamic conditions and development of oxidation and pyrolysis zones. During the atmospheric gasification experiments, the values of BTEX for the Velenje lignite dropped from 3434 μg/l to 1364 μg/l and for the Oltenia lignite from 1833 μg/l to 978 μg/l. A similar downward trend in the concentrations of BTEX was observed for the pressurized experiments. For the Velenje trial a drop from 1111.6 μg/l to 211.2 μg/l and for the Oltenia - from 1695 μg/l to 688 μg/l was observed. Concentrations of phenolic compounds during the atmospheric gasification experiments varied significantly during both atmospheric trials and no significant trends were noticed.
Show more [+] Less [-]Optimization of Coagulation/Flocculation Treatment of Brewery Wastewater Employing Organic Flocculant Based of Vegetable Tannin Full text
2019
Tonhato Junior, Alcides | Hasan, Salah Din Mahmud | Sebastien, Nyamien Yahaut
The brewing industry is an important sector in the world economy, and its production process generates a large amount of wastewater. It is essential the proper treatment of this wastewater and a significant amount of biomass may be recovered by coagulation/flocculation process. When using vegetable tannin as an organic flocculant, biomass can be used in the preparation of organic fertilizer, unlike what would occur if a metal base flocculant was used, some of which are considered to be toxic. This work presents a study on the use of vegetable tannin as flocculant agent (Tanfloc SL) for the treatment of brewery wastewater, which also contains microalgae originated from an aerated pond of a local brewery industry. Experiments of coagulation/flocculation and sedimentation were carried out using jar test equipment. A sequential 2² factorial design and two-factor Doehlert design were used to determine the optimum levels of pH and tannin concentration for turbidity and apparent color removals from the wastewater. The higher efficiency results in the biomass separation were obtained by employing 0.23 mL L⁻¹ of vegetable tannin at pH = 4.9, resulting in the substantial removal of approximately 99% of turbidity and apparent color. The removals of biomass and nutrient components were also evaluated: N-NH⁴⁺ (80.8%), N-NO₂- (83.6%), N-NO₃ (56.9%), total phosphorus (82.3%), orthophosphate (76.2%), COD (96.5%), BOD (69.4%), and total solids (40.8%). The Tanfloc SL showed to be efficient in flocculation of the brewery effluent, allowing the reuse of water in industry and the recovered biomass material containing nutrients in agriculture.
Show more [+] Less [-]Effectivity–ecosphere–economics in nZEB retrofit procedures Full text
2019
Ryńska, Elżbieta | Koźmińska, Urszula | Rucińska, Joanna
Sustainable development has by now become an element deeply integrated in the everyday design. It has many shades and may be found under many names. We speak about resiliency in design and procurement of passive, ecologic, plus energy, or nZEB buildings. Nevertheless, if we look closely, we may distinguish certain characteristic ideas. First, sustainable development of societies and urbanization processes should be consistent on a deeper level than presently, and be included within design processes, organization, and planning, as well as modernization and redevelopment procedures of existing urban tissue. Secondly, urbanization should be perceived holistically, as an interaction and harmonious development of both natural and manmade environments, with solutions based on the best technical and technological standards available. Lastly, described ideas are achievable only, if we include continuous cooperation between urban planners, architects, specialist consultants, as well as energy-efficient interdisciplinary solutions to achieve high standard energy measures. One of the thresholds is economic feasibility; the other is health and well-being of the users which should always be discussed as a priority. This paper—outside a brief theoretical approach to initial procedures in design management—will dwell on transformation and modernization of an existing building belonging to the Warsaw University of Technology, one of the oldest universities in Poland, its founding dating back to the beginning of the twentieth century. In 2015, a Nordic Finance Mechanism grant dedicated to the nZEB technology transfer from Norway to Poland was awarded to a group of researchers from Warsaw University of Technology and NTNU Trondheim. The main aim of the project is implementation of nZEB knowledge in Poland, as well as preparation of two integrated concept designs for public (University) buildings as exemplary case studies which could act as the benchmarks for other public buildings.
Show more [+] Less [-]Microbial Origin of Excreted DNA in Particular Fractions of Extracellular Polymers (EPS) in Aerobic Granules Full text
2019
Rusanowska, Paulina | Cydzik-Kwiatkowska, Agnieszka | Wojnowska-Baryła, Irena
The study investigated species composition and polysaccharides, proteins, and eDNA content in EPS fractions (soluble, Sol-EPS; loosely bound, LB-EPS; tightly bound, TB-EPS) in nitrifying aerobic granules from reactor operated at a high load of nitrogen 0.5 kg TKN/(m³ × day). In the study, polysaccharides predominated in Sol-EPS, whereas proteins were the main component of bound EPS. eDNA was only detectable in TB-EPS. In Sol-EPS, eDNA originating from Pseudomonales predominated; species belonging to Pseudomonales produce glue-like polysaccharides that enable surface colonization. In all EPS fractions, high abundance of Acinetobacter sp. was noted. In TB-EPS, Thauera sp. was present in high abundance (25.6%) that produce polymers ensuring compact granule structure and that participate in many key metabolic processes for nitrogen conversions in wastewater treatment plants such as heterotrophic nitrification or denitrification. The study indicates that each EPS fraction in aerobic granules represents micro-environment facilitating the growth of species that produce a component of EPS with function essential for surrounding cells.
Show more [+] Less [-]In Situ Synthesis and Photocatalytic Properties of Titanium Dioxide Nanoparticles on Cotton Fabrics Full text
2019
Bao, Zhanxia | Wang, Shuhua | Yu, Xiaoying | Gao, Yindong | Wen, Zeling
In this paper, nanosized titanium dioxide as catalysts for degrading dye wastewater was in situ synthesized on the surface of cotton fabrics used tetrabutyl titanate as precursor. The morphology and structure of prepared catalysts were characterized by scanning electron microscopy, energy-dispersive spectrometer, and X-ray diffraction. The characterization results showed that anatase nanosized titanium dioxide was successfully synthesized in situ on cotton fabrics and had excellent dispersibility. Subsequently, the effects of irradiation time, catalyst dosage, dye concentration, initial pH value of dye, hydrogen peroxide dosage, and dye type on dye degradation rate were investigated one by one by a photocatalytic performance test. The test results indicated that the degradation rates of methylene blue, methyl orange, and rhodamine B were 90.4%, 81.4%, and 58.3%, separately, at catalyst dosage of 4.8 g/L, initial dye concentration of 10 mg/L, pH of 7, and hydrogen peroxide dosage of 0.24 mol/L, after 4 h of UV irradiation.
Show more [+] Less [-]Presence of Pesticides and Toxicity Assessment of Agricultural Soils in the Quintana Roo Mayan Zone, Mexico Using Biomarkers in Earthworms (Eisenia fetida) Full text
2019
Andrade-Herrera, Moises | Escalona-Segura, Griselda | González-Jáuregui, Mauricio | Reyna-Hurtado, Rafael A. | Vargas-Contreras, Jorge A. | Rendón-von Osten, Jaime
Agriculture intensification and the use of pesticides have led to biodiversity loss due to soil toxic compounds. Thus, soil contamination studies are important to understand the negative effects in the physicochemical interactions. The use of biomarkers through bioindicators is a useful tool for assessing toxicity in agricultural environments complemented with the determination of pesticides. The objectives of this study were to determine the presence of organochlorine (OCPs) and organophosphate (OPPs) pesticides and the soil’s potential toxicity in agricultural fields with different crops from the center of Quintana Roo State, using a set of enzymatic biomarkers (BMs), such as acetylcholinesterase (AChE), glutathione-S-Transferase (GST), and catalase (CAT) on earthworms (Eisenia fetida). Earthworms were exposed for 96 h on nine different agricultural soils as well as on a reference soil from a conservation area. Within all samples of soils, only OCPs were detected in low concentrations (ranged from non-detected to 1.40 ppm). However, no correlation was observed between these pesticides and the BMs activity. AChE and CAT activity was significantly inhibited in at least one agricultural soil if compared to the conservation area, while no significant differences of GST were observed. The AChE activity observed suggests the presence of anticholinergic substances (that were neither detected nor determined analytically) in the sampled soils. The characterization of oxidative stress BMs was not correlated with the OCPs analyzed. Our results demonstrate that further studies of toxicity under field conditions are required, given the complexity of environmental conditions outside the laboratory.
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