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Smoked cigarette butt leachate impacts survival and behaviour of freshwater invertebrates Texte intégral
2020
Green, Dannielle Senga | Kregting, Louise | Boots, Bas
Smoked cigarette filters a. k.a. “butts”, composed of plastic (e.g. cellulose acetate) are one of the world’s most common litter items. In response to concerns about plastic pollution, biodegradable cellulose filters are being promoted as an environmentally safe alternative, however, once smoked, both contain toxins which can leach once discarded. The impacts of biodegradable butts as littered items on the receiving environment, in comparison with conventional butts has not yet been assessed. A freshwater mesocosm experiment was used to test the effects of leachate from smoked cellulose acetate versus smoked cellulose filters at a range of concentrations (0, 0.2, 1 and 5 butts L⁻¹) on the mortality and behaviour of four freshwater invertebrates (Dreissena polymorpha, Polycelis nigra, Planorbis planorbis and Bithynia tentaculata). Leachate derived from 5 butts L⁻¹ of either type of filter caused 60–100% mortality to all species within 5 days. Leachate derived from 1 butt L⁻¹ of either type resulted in adults being less active than those exposed to no or 0.2 butts L⁻¹ leachate. Cigarette butts, therefore, regardless of their perceived degradability can cause mortality and decreased activity of key freshwater invertebrates and should always be disposed of responsibly.
Afficher plus [+] Moins [-]Emission characteristics and associated assessment of volatile organic compounds from process units in a refinery Texte intégral
2020
Feng, Yunxia | Xiao, Anshan | Jia, Runzhong | Zhu, Shengjie | Gao, Victor | Li, Bo | Shi, Ning | Zou, Bing
The accuracy and reliability of volatile organic compound (VOC) emission data are essential for assessing emission characteristics and their potential impact on air quality and human health. This paper describes a new method for determining VOC emission data by multipoint sampling from various process units inside a large-scale refinery. We found that the emission characteristics of various production units were related to the raw materials, products, and production processes. Saturated alkanes accounted for the largest fraction in the continuous catalytic reforming and wastewater treatment units (48.0% and 59.2%, respectively). In the propene recovery unit and catalytic cracking unit, alkenes were the most dominant compounds, and propene provided the largest contributions (57.8% and 23.0%, respectively). In addition, n-decane (12.6%), m,p-xylene (12.4%), and n-nonane (8.9%) were the main species in the normal production process of the delayed coking unit. Assessments of photochemical reactivity and carcinogenic risk were carried out, and the results indicate that VOC emissions from the propene recovery unit and catalytic cracking unit should be controlled to reduce the ozone formation potential; in addition, alkenes are precedent-controlled pollutants. The cancer risk assessments reveal that 1,2-dibromoethane, benzene, 1,2-dichloroethane, and chloroform were the dominant risk contributors, and their values were much higher than the standard threshold value of 1.0 × 10⁻⁶ but lower than the significant risk value defined by the US Supreme Court. Based on the VOC composition and a classification algorithm, the samples were classified into eight main groups that corresponded to different process units in the petroleum refinery. In conclusion, this work provides valuable data for investigating process-specific emission characteristics of VOCs and performing associated assessments of photochemical reactivity and carcinogenic risk in petrochemical refineries.
Afficher plus [+] Moins [-]Water Quality Assessment Based on HFB I& BMWP Index In Karoon River ,Khouzestan Provience, (Northwest of Persian Gulf) Texte intégral
2020
Sahar Jalili
Score-based biotic indices are widely used to evaluate the water quality of streams and rivers. The main objective of this study was the assessmentof the water quality of Karoon River throught biotic indices based on the Family Biotic Index (HFBI), and the Biological Monitoring Working Party Score System (BMWP). Macroinveratabrate communities are one of the most used groups in assessment of water quality, since they respond directively to the level of contamination of aquatic ecosystems. Sampling were performed in 4 stations (Menikh, Zhian Canal, Bahrakani and Dahaneh). Sampling was carried in each station over one year ( winter, spring, summer and autumn). Macroinvertebrates were collected by the grab quantitative sampller. Four phylaum (Nematoda, Annelidae, Mollusca and Arthropoda) distributed amoung 11 families were sampled. Station1 (Menikh) had the highest Macroinveratabrate diversity and richness. The highest density of aquatic invertabrates were recorded in winter (Annelidae 46%, Crustacea 28% ,Mullusca 21% and Diptera 5% ) and spring ( Mullusca 58%, Crustacea 27%,Nematoda 10% and Anellidae 5%) respectively. The BMWP index showed that the water quality was in the reguallar category (for Menikh, Zhian Canal and Bahrakani) and in the poor category (for Dahaneh). HFBI index pointed out the water quality was in the reguallar catagorry (for Menikh, Zhian Canal and Bahrakani) and poor category (for Dahaneh) . Biotic indices used reflected the changes to the water quality.
Afficher plus [+] Moins [-]Identifying and prioritizing the factors influencing industrial waste management using Fuzzy Analytical Hierarchy Process (FAHP) Texte intégral
2020
Mina Moeeni | Ghasemali Omrani | Nematallah Khorasani | Reza Arjomandi
Over the past few decades, human societies have faced one of the most significant consequences of industrial development. That is the improper transportation and disposal of hazardous and industrial-specific waste, which accounts for a large share of the total pollution of the environment, and its destructive effects on creating environmental crises are quite evident. The plating industry is one of the main consumers of toxic chemicals used for different applications. However, because of the lack of a comprehensive model, hazardous waste management has not yet met the current needs, and its principles still require more development. This study was carried out using tools and standards including Multi-Criteria Decision Support Systems (MCDSS) and Fuzzy Analytical Hierarchy Process (FAHP) to rank the contributions of effective components to the plating industry in a case study conducted and implemented in Paitakht Industrial District of Tehran. In order to realize this objective, after extracting 10 components effective in optimizing the management of industrial wastes, questionnaires were used to survey experts to verify the components. The factors were identified using the Delphi method through the analysis of frequency carried out using a second questionnaire based on the results of the analysis of the data extracted from the first questionnaire. The results showed that components contributing to the optimal management of industrial waste included leadership and management, policy, strategy, technology and mode of collection and transportation, economic factors, policy making, expertise, culture, education, and the amount and composition of waste, in that order.
Afficher plus [+] Moins [-]Assessing the risk of environmental pollution caused by tourism activities (recreation – sports) in natural environments of Shahrood County Texte intégral
2020
Sepideh Hosseini Dinani | Seyed Mostafa Tayebi Sani | Bagher Morsal | Ali Fahiminejad
The purpose of this study is to identify environmental pollution caused by tourism activities in Shahrood county and environmental risk assessment. In the first step, tourism sites (recreational-sports) in the study area were identified. In the next step, the type and extent of environmental pollution in each were identified and their zoning map was drawn. Finally, risk assessment was performed using risk assessment models. The results showed that some types of environmental pollution can be seen in these areas, but the pollution caused by solid waste has been present in all tourist sites. The daily sewage pollution rate produced by natural tourism in Shahrood is relatively high and is about 140kg/day and the waste production rate is 10 tons per year. Also; the average measured sound level is 88dB. In terms of the level of risk of pollutants, the three most common types of pollution are solid waste and then sewage. The lowest type of pollution is related to air pollution. As for air pollution, the type of risk is obvious and the level of the aspect is low. In the case of noise pollution, the type of risk is obvious and the level of risk is high. In the case of wastewater pollution and waste pollution, the type of risk, the level and the level of the aspect is the ultimate. The principles of sustainable tourism in this region have not been observed and the need to develop a comprehensive and strategic model for tourism management is essential.
Afficher plus [+] Moins [-]Effect of sulfamethazine on surface characteristics of biochar colloids and its implications for transport in porous media Texte intégral
2020
Yang, Wen | Feng, Tongtong | Flury, Markus | Li, Baoguo | Shang, Jianying
Antibiotics are contaminants of emerging concern due to their potential effect on antibiotic resistance and human health. Antibiotics tend to sorb strongly to organic materials, and biochar, a high efficient agent for adsorbing and immobilizing pollutants, can thus be used for remediation of antibiotic-contaminated soil and water. The effect of ionizable antibiotics on surface characteristics and transport of biochar colloids (BC) in the environment is poorly studied. Column experiments of BC were conducted in 1 mM NaCl solution under three pH (5, 7, and 10) conditions in the presence of sulfamethazine (SMT). Additionally, the adsorption of SMT by BC and the zeta potential of BC were also studied. The experimental results showed that SMT sorption to BC was enhanced at pH 5 and 7, but reduced at pH 10. SMT sorption reduced the surface charge of BC at pH 5 and 7 due to charge shielding, but increased surface charge at pH 10 due to adsorption of the negatively charged SMT species. The mobility of BC was inhibited by SMT under acidic or neutral conditions, while enhanced by SMT under alkaline conditions, which can be well explained by the change of electrostatic repulsion between BC and sand grains. These findings imply that pH conditions played a crucial role in deciding whether the transport of BC would be promoted by SMT or not. Biochar for antibiotics remediation will be more effective under acidic and neutral soil conditions, and the mobility of BC will be less than in alkaline soils.
Afficher plus [+] Moins [-]High carbohydrate diet partially protects Nile tilapia (Oreochromis niloticus) from oxytetracycline-induced side effects Texte intégral
2020
Limbu, Samwel Mchele | Zhang, Han | Luo, Yuan | Chen, Li-Qiao | Zhang, Meiling | Du, Zhen-Yu
Antibiotics used in global aquaculture production cause various side effects, which impair fish health. However, the use of dietary composition such as carbohydrate, which is one of the dominant components in fish diets to attenuate the side effects induced by antibiotics, remains unclear. We determined the ability of high carbohydrate diet to protect Nile tilapia (Oreochromis niloticus) from oxytetracycline-induced side effects. Triplicate groups of thirty O. niloticus (9.50 ± 0.08 g) were fed on medium carbohydrate (MC; 335 g/kg) and high carbohydrate (HC; 455 g/kg) diets without and with 2.00 g/kg diet of oxytetracycline (80 mg/kg body weight/day) hereafter, MCO and HCO for 35 days. Thereafter, we assessed growth performance, hepatic nutrients composition and metabolism, microbiota abundance, immunity, oxidative and cellular stress, hepatotoxicity, lipid peroxidation and apoptosis. To understand the possible mechanism of carbohydrate protection on oxytetracycline, we assessed the binding effects and efficiencies of mixtures of medium and high starch with oxytetracycline as well as the MCO and HCO diets. The O. niloticus fed on the MCO and HCO diets had lower growth rate, nutrients utilization and survival rate than those fed on the MC and HC diets, respectively. Dietary HCO increased hepatosomatic index and hepatic protein content of O. niloticus than MCO diet. The O. niloticus fed on the HCO diet had lower mRNA expression of genes related to protein, glycogen and lipid metabolism compared to those fed on the MCO diet. Feeding O. niloticus on the HCO diet increased innate immunity and reduced pathogenic bacteria, pro-inflammation, hepatotoxicity, cellular stress and apoptosis than the MCO diet. The high starch with oxytetracycline and HCO diet had higher-oxytetracycline binding effects and efficiencies than the medium starch with oxytetracyline and MCO diet, respectively. Our study demonstrates that, high carbohydrate partially protects O. niloticus from oxytetracycline-induced side effects by binding the antibiotic. Incorporating high carbohydrate in diet formulation for omnivorous fish species alleviates some of the side effects caused by antibiotics.
Afficher plus [+] Moins [-]β-blockers in the environment: Distribution, transformation, and ecotoxicity Texte intégral
2020
Yi, Ming | Sheng, Qi | Sui, Qian | Lu, Huijie
β-blockers are a class of medications widely used to treat cardiovascular disorders, including abnormal heart rhythms, high blood pressure, and angina pectoris. The prevalence of β-blockers has generated a widespread concern on their potential chronic toxicity on aquatic organisms, highlighting the necessity of comprehensive studies on their environmental distribution, fate, and toxicity. This review summarizes the up-to-date knowledge on the source, global distribution, analytical methods, transformation, and toxicity of β-blockers. Twelve β-blockers have been detected in various environmental matrices, displaying significant temporal and spatial variations. β-blockers can be reduced by 0–99% at wastewater treatment plants, where secondary processes contribute to the majority of removal. Advanced oxidation processes, e.g., photocatalysis and combined UV/persulfate can transform β-blockers more rapidly and completely than conventional wastewater treatment processes, but the transformation products could be more toxic than the parent compounds. Propranolol, especially its (S)-enantiomer, exhibits the highest toxicity among all β-blockers. Future research towards improved detection methods, more efficient and cost-effective removal techniques, and more accurate toxicity assessment is needed to prioritize β-blockers for environmental monitoring and control worldwide.
Afficher plus [+] Moins [-]Associations between renal functions and exposure of arsenic and polycyclic aromatic hydrocarbon in adults living near a petrochemical complex Texte intégral
2020
Yuan, Tzu-Hsuen | Ke, Deng-Yuan | Wang, Joyce En-Hua | Chan, Chang-Chuan
The understanding for the impact of petrochemical pollutants exposure on renal functions is limited.Our study examined the associations between renal functions and pollutants exposure in adult residents living in the vicinity of a petrochemical industry.We recruited 2069 adult residents near a big petrochemical complex in Taiwan in 2009–2012, and they were categorized into high exposure (HE) and low exposure (LE) groups based on their address to source by 10 km radius. Study subjects were measured the urinary levels of arsenic, cadmium, mercury, thallium, and 1-hydroxypyrene (1-OHP). The estimated glomerular filtration rate (eGFR) was calculated using the Taiwanese Chronic Kidney Disease Epidemiology Collaboration equation, and the chronic kidney disease (CKD) prevalence and risks were defined according to KDIGO 2012 guidelines. Adjusted generalized linear and logistic regression models were applied to evaluate the associations between petrochemical exposure and renal functions.Subjects in the HE areas had significantly lower eGFR, higher CKD prevalence, and higher levels of urinary arsenic, cadmium, mercury, thallium and 1-OHP. The closer to complex and high exposure group of study subjects were significantly associated with the decrease in eGFR, higher ORs for CKD and high-intermediate risk of CKD. In addition, the study subjects who had two-fold urinary arsenic and 1-OHP levels were significantly with decreased 0.68 and 0.49 ml/min/1.73 m2 of eGFR, respectively.Residing closer and higher arsenic and polycyclic aromatic hydrocarbon exposure were associated with the renal impairment and risks of CKD among the residential population near the petrochemical industry.
Afficher plus [+] Moins [-]Rainbow trout (Oncorhynchus mykiss) chemosensory detection of and reactions to copper nanoparticles and copper ions Texte intégral
2020
Razmara, Parastoo | Sharpe, Justin | Pyle, Gregory G.
Copper is known to interfere with fish olfaction. Although the chemosensory detection and olfactory toxicity of copper ions (Cu²⁺) has been heavily studied in fish, the olfactory-driven detection of copper nanoparticles (CuNPs)—a rapidly emerging contaminant to aquatic systems—remains largely unknown. This study aimed to investigate the olfactory response of rainbow trout to equitoxic concentrations of CuNPs or Cu²⁺ using electro-olfactography (EOG, a neurophysiological technique) and olfactory-mediated behavioural assay. In the first experiment, the concentration of contaminants known to impair olfaction by 20% over 24 h (EOG-based 24-h IC20s of 220 and 3.5 μg/L for CuNPs and Cu²⁺, respectively) were tested as olfactory stimuli using both neurophysiological and behavioural assays. In the second experiment, to determine whether the presence of CuNPs or Cu²⁺ can affect the ability of fish to perceive a social cue (taurocholic acid (TCA)), fish were acutely exposed to one form of Cu-contaminants (approximately 15 min). Following exposure, olfactory sensitivity was measured by EOG and olfactory-mediated behaviour within a choice maze was recorded in the presence of TCA. Results of neurophysiological and behavioural experiments demonstrate that rainbow trout can detect and avoid the IC20 of CuNPs. The IC20 of Cu²⁺ was below the olfactory detection threshold of rainbow trout, as such, fish did not avoid Cu²⁺. The high sensitivity of behavioural endpoints revealed a lack of aversion response to TCA in CuNP-exposed fish, despite this change not being present utilizing EOG. The reduced response to TCA during the brief exposure to CuNPs may be a result of either olfactory fatigue or blockage of olfactory sensory neurons (OSNs) by CuNPs. The observed behavioural interference caused by CuNP exposure may indicate that CuNPs have the ability to interfere with other behaviours potentially affecting fitness and survival. Our findings also revealed the differential response of OSNs to CuNPs and Cu²⁺.
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