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Development of a nematode offspring counting assay for rapid and simple soil toxicity assessment
2018
Kim, Shin Woong | Moon, Jongmin | Jeong, Seung-Woo | An, Youn-Joo
Since the introduction of standardized nematode toxicity assays by the American Society for Testing and Materials (ASTM) and International Organization for Standardization (ISO), many studies have reported their use. Given that the currently used standardized nematode toxicity assays have certain limitations, in this study, we examined the use of a novel nematode offspring counting assay for evaluating soil ecotoxicity based on a previous soil-agar isolation method used to recover live adult nematodes. In this new assay, adult Caenorhabditis elegans were exposed to soil using a standardized toxicity assay procedure, and the resulting offspring in test soils attracted by a microbial food source in agar plates were counted. This method differs from previously used assays in terms of its endpoint, namely, the number of nematode offspring. The applicability of the bioassay was demonstrated using metal-spiked soils, which revealed metal concentration-dependent responses, and with 36 field soil samples characterized by different physicochemical properties and containing various metals. Principal component analysis revealed that texture fraction (clay, sand, and silt) and electrical conductivity values were the main factors influencing the nematode offspring counting assay, and these findings warrant further investigation. The nematode offspring counting assay is a rapid and simple process that can provide multi-directional toxicity assessment when used in conjunction with other standard methods.
Mostrar más [+] Menos [-]A Review of Socio-acoustic Surveys for Soundscape Studies
2018
Engel, Margret Sibylle | Fiebig, André | Pfaffenbach, Carmella | Fels, Janina
PURPOSE OF REVIEW: This article reviews the literature and presents the current status of the use of socio-acoustic surveys in soundscape studies, through the indication of appropriate question formats, types, and topics for each data collection method (soundwalks, interviews, listening tests, and focus group) for the involved public and acoustic stimuli. RECENT FINDINGS: The ISO 12913-2 establishes ways of data collection and reporting requirements for soundscape studies (International Organization for Standartization 2017), including the triangulation technique. This standard recommends some data collection methods, like soundwalks and interviews. Even so, some authors are using different methods to collect data, such as focus group and listening tests. This study investigated through 52 peer-reviewed papers published on the last 20 years the current status of socio-acoustic studies regarding question topics and types, used stimuli, and characteristics about the participants, using the four major adopted data collection methods in soundscape studies: soundwalks, interviews, listening tests, and focus group. Some topics like “soundscape quality” and “sound sources identification and evaluation” are common in the recent studies, as well as the adoption of some question types such as semantic differential scale, the staple scale, and ranking order scale.
Mostrar más [+] Menos [-]Public awareness and attitudes towards naval sonar mitigation for cetacean conservation: A preliminary case study in Fairfax County, Virginia (the DC Metro area)
2011
Zirbel, K. | Balint, P. | Parsons, E.C.M.
The potential impacts of naval sonar on cetaceans has led to a series of court cases and statements of concern by international organizations. However, there has been no research conducted on attitudes of the general public with respect to this issue. To investigate this, a preliminary public survey was conducted in Fairfax, Virginia (the Washington, DC Metro region). The majority of the public sampled believed that naval sonar impacted marine mammals (51.3%), that the US Navy should not be exempt from environmental regulations in time of peace (75.2%), and that sonar use should be moderated if it impacts cetaceans (75.8%). Individuals who were conservative, Republican, and have served in the military were more likely to believe the Navy should be exempt from marine mammal protection regulations. In addition, expert interviews were conducted to gain opinions on the potential ramifications of the recent US Supreme Court case on naval sonar mitigation.
Mostrar más [+] Menos [-]Correlation Analysis of Heavy Metals Contents of Malva sylvestris L. plant and Its Extracts from Polluted and Non-polluted Locations in Niš, Republic of Serbia
2019
Kostic, Danijela | Arsić, Biljana | Ranđelović, Saša | Pavlović, Aleksandra | Tošić, Snežana | Stojanović, Gordana
Malva sylvestris L. is a widely consumed edible-medicinal plant growing all around the world. The aim of our study was the determination of the concentration levels of heavy metals in M. sylvestris L. samples and their extracts from polluted and non-polluted locations in Niš, Republic of Serbia. The analysis of heavy metals was performed by the AAS (Atomic Absorption Spectroscopy) method from soil, plants, and extracts. The heavy metals content (Fe, Cu, Mn, Ni, Pb, Zn, and Cd) in the soil and plants from the contaminated site is increased, but the coefficients of metal uptake are not significantly different in plants from polluted and non-polluted areas. The highest content of metals was found in aqueous, then water-alcoholic, and the smallest content was determined in alcoholic solutions. The content of the tested metals is within the limits recommended by international organizations, so the plant and its extracts can be safely used.
Mostrar más [+] Menos [-]Removal of Heavy Metals Using Rhamnolipid Biosurfactant on Manganese Nodules
2019
Lee, Aleum | Kim, Kyoungrean
The objective of this study is to identify the feasibility of using rhamnolipid biosurfactant to remediate heavy metals contained in manganese nodules collected from the Clarion-Clipperton Fracture Zone, Pacific Ocean. Deep-sea manganese nodules may represent one of the most important future natural resources for heavy metals due to the depletion of resources on land. Since international marine environment guidelines for deep-sea mining will be set up by international organisations in the 2020s, remediation technologies are urgently required for deep-sea mining tailings. We show that rhamnolipid biosurfactant is an environmentally friendly substance and can be successfully used for the remediation of heavy metals in deep-sea mining tailings under various reaction conditions. Rhamnolipids therefore represent a useful extracting agent for heavy metals in deep-sea mining tailings. The removal of nickel (Ni), copper (Cu), and cadmium (Cd) would be enhanced in the presence of rhamnolipids with specific reaction times and concentrations. Future actual remediation technologies should be developed using rhamnolipid biosurfactant on the basis of these results.
Mostrar más [+] Menos [-]Quantification of polychlorinated biphenyl contamination using human placenta as biomarker from Punjab Province, Pakistan
2018
Naqvi, Anber | Qadir, Abdul | Mahmood, Adeel | Baqar, Mujtaba | Aslam, Iqra | Sajid, Farhan | Mumtaz, Mehvish | Li, Jun | Zhang, Gan
The present study biomonitored the placental polychlorinated biphenyl (PCB) concentrations in women from Punjab Province, Pakistan, that provides the pioneer data for occurrence and body burden of PCBs in placental tissues from South Asian women. The ∑₃₄PCB concentrations in placental tissues were ranged from 20.2 to 115.98 ng/g lipid weight (lip. wt.), with predominance of tetra-PCB (54.67%). The levels of ∑₈DL-PCBs and ∑₆-indicator PCBs were ranged from 2.03 to 27.64 ng/g (lip. wt.) and 1.71 to 30.8 ng/g (lip. wt.), respectively. The WHO-TEQ2005 values for DL-PCBs were ranged from 1.18 × 10⁻⁵ to 0.067 ng/g (lip. wt.), with highest value evaluated for CB-126. The estimated daily intake (EDI) for DL-PCBs was ranged from 9.27 × 10⁻⁸ to 5.25 × 10⁻⁴ pg WHO-TEQ/kg body weight (bw), which was within the tolerable daily intake (TDI) values established by international organizations. The spatial distribution patterns of Σ₃₄PCB concentrations from study area have shown relative higher concentrations in samples from urban and industrial cities than rural areas, and industrial and urban releases along with e-waste handling were recognized as vital PCB sources in the environment. In order to ascertain the transplacental transfer of PCBs, the fetal growth parameters were correlated with the ∑₃₄PCB concentrations in placental tissues. The relationship between ∑₃₄PCB concentrations in placental tissues and infant’s anthropometric measures through multiple linear regression showed a negative correlation of infant’s body weight (R² = 0.0728), crown to heel length (R² = 0.068), head circumference (R² = 0.0342), chest circumference (R² = 0.0001), and mid arm circumference (R² = 0.0096) that noticeably highlights the inhibited fetal anthropometric development associated with maternal PCB bioaccumulation. Hence, an immediate elimination of ongoing PCB addition in the studied area has been emphasized and further investigations are suggested to appropriately manage the public and neonatal health risks in the region.
Mostrar más [+] Menos [-]Can toxicants used against cotton mealybug Phenacoccus solenopsis be compatible with an encyrtid parasitoid Aenasius bambawalei under laboratory conditions?
2017
Badshah, Hayat | Ullah, Farman | Calatayud, Paul Andre | Ullah, Hidayat | Ahmad, Bashir
The cotton mealybug, Phenacoccus solenopsis Tinsley (Sternorrhyncha: Pseudococcidae) is a serious pest of various cultivated plants in Pakistan. Recent reports show that the parasitoid Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae) is a good biocontrol agent of the pest. Compatibleness is important in any IPM programme, and the insecticide used must have little or no effects on the biological control agent. This study investigated the compatibility of neem treatments and a commercial insecticide, imidacloprid on A. bambawalei. Bioassays were laid out in a completely randomized design (CRD) under laboratory conditions. Results showed that the adult stage of the parasitoid was more susceptible to the commercial insecticide imidacloprid than the concealed pupal stage. Moreover, on the basis of the International Organization for Biological Control (IOBC) toxicity categories of the commercial insecticide, imidacloprid was moderately toxic throughout the study period (Ex >80%) while neem was slightly toxic after 24 h of use (Ex <80%). Results also suggest that A. bambawalei release should be delayed for at least 1 week after neem treatments. Because imidacloprid destroys A. bambawalei, it might cause resurgence of P. solenopsis; thus, farmers should avoid integrating the insecticide in the control of P. solenopsis.
Mostrar más [+] Menos [-]Characteristics and trends on global environmental monitoring research: a bibliometric analysis based on Science Citation Index Expanded
2017
Zhang, Di | Fu, Hui-Zhen | Ho, Yuh-Shan
A bibliometric analysis based on the Science Citation Index Expanded from Web of Science was carried out to provide insights into research activities and trends of the environmental monitoring from 1993 to 2012. Study emphases covered publication outputs, language, categories, journals, countries/territories, institutions, words, and hot issues. The results indicated that the annual output of environmental monitoring publications increased steadily. The environmental sciences and analytical chemistry were the two most common categories. Environmental Monitoring and Assessment published the most articles. The USA and the UK ranked in the top two in terms of all five indicators. The U.S. Environmental Protection Agency took the leading position of the institutions in terms of publication output. The synthesized analysis by words in title, author keywords, and KeyWords Plus provided important clues for hot issues. Researchers paid more attention on water environment monitoring than other environmental factors. The contaminants including organic contaminants, heavy metal, and radiation were most common research focuses, and the organic contaminants and heavy metal of the degree of concern were gradually rising. Sensor and biosensor played an important role in the field of environmental monitoring devices. In addition to conventional device detection method, the remote sensing, GIS, and wireless sensor networks were the mainstream environmental monitoring methods. The international organization, social awareness, and the countries’ positive and effective political and policies promoted the published articles.
Mostrar más [+] Menos [-]Chemical Leasing business models and corporate social responsibility
2014
Moser, Frank | Jakl, Thomas | Joas, Reihard | Dondi, Francesco
Chemical Leasing is a service-oriented business model that shifts the focus from increasing sales volume of chemicals towards a value-added approach. Recent pilot projects have shown the economic benefits of introducing Chemical Leasing business models in a broad range of sectors. A decade after its introduction, the promotion of Chemical Leasing is still predominantly done by the public sector and international organizations. We show in this paper that awareness-raising activities to disseminate information on this innovative business model mainly focus on the economic benefits. We argue that selling Chemical Leasing business models solely on the grounds of economic and ecological considerations falls short of branding it as a corporate social responsibility initiative, which, for this paper, is defined as a stakeholder-oriented concept that extends beyond the organization’s boundaries and is driven by an ethical understanding of the organization’s responsibility for the impact of its business activities. For the analysis of Chemical Leasing business models, we introduce two case studies from the water purification and metal degreasing fields, focusing on employees and local communities as two specific stakeholder groups of the company introducing Chemical Leasing. The paper seeks to demonstrate that Chemical Leasing business models can be branded as a corporate social responsibility initiative by outlining the vast potential of Chemical Leasing to improve occupational health and safety and to strengthen the ability of companies to protect the environment from the adverse effects of the chemicals they apply.
Mostrar más [+] Menos [-]Tripartite equilibrium strategy for a carbon tax setting problem in air passenger transport
2018
Xu, Jiuping | Qiu, Rui | Tao, Zhimiao | Xie, Heping
Carbon emissions in air passenger transport have become increasing serious with the rapidly development of aviation industry. Combined with a tripartite equilibrium strategy, this paper proposes a multi-level multi-objective model for an air passenger transport carbon tax setting problem (CTSP) among an international organization, an airline and passengers with the fuzzy uncertainty. The proposed model is simplified to an equivalent crisp model by a weighted sum procedure and a Karush-Kuhn-Tucker (KKT) transformation method. To solve the equivalent crisp model, a fuzzy logic controlled genetic algorithm with entropy-Bolitzmann selection (FLC-GA with EBS) is designed as an integrated solution method. Then, a numerical example is provided to demonstrate the practicality and efficiency of the optimization method. Results show that the cap tax mechanism is an important part of air passenger trans’port carbon emission mitigation and thus, it should be effectively applied to air passenger transport. These results also indicate that the proposed method can provide efficient ways of mitigating carbon emissions for air passenger transport, and therefore assist decision makers in formulating relevant strategies under multiple scenarios.
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