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Changes to an urban marina soundscape associated with COVID-19 lockdown in Guadeloupe Texto completo
2021
Bertucci, Frédéric | Lecchini, David | Greeven, Céline | Brooker, Rohan M. | Minier, Lana | Cordonnier, Sébastien | René-Trouillefou, Malika | Parmentier, Eric
Changes to an urban marina soundscape associated with COVID-19 lockdown in Guadeloupe Texto completo
2021
Bertucci, Frédéric | Lecchini, David | Greeven, Céline | Brooker, Rohan M. | Minier, Lana | Cordonnier, Sébastien | René-Trouillefou, Malika | Parmentier, Eric
In 2020, the COVID-19 pandemic led to government-enforced limits on activities worldwide, causing a marked reduction of human presence in outdoors environments, including in coastal areas that normally support substantial levels of boat traffic. These restrictions provided a unique opportunity to quantify the degree to which anthropogenic noise contributes to and impacts underwater soundscapes. In Guadeloupe, French West Indies, a significantly lower number of motor boats were recorded in the vicinity of the major urban marina during the peak of the first COVID-19 lockdown (April–May 2020), compared with the number recorded post-lockdown. The resumption of human activities at the end of May was correlated with a maximum increase of 6 decibels in the ambient noise level underwater. The change in noise level did not impact daily sound production patterns of vocal fishes, with increased activity at dusk seen both during and after the lockdown period. However, during the lockdown vocal activity was comprised of a reduced number of sounds, suggesting that anthropogenic noise has the potential to interfere with vocalization behaviours in fishes.
Mostrar más [+] Menos [-]Changes to an urban marina soundscape associated with COVID-19 lockdown in Guadeloupe Texto completo
2021
Bertucci, Frédéric | Lecchini, David | Greeven, Céline | Brooker, Rohan M | Minier, Lana | Cordonnier, Sébastien | René-Trouillefou, Malika | Parmentier, Eric
peer reviewed
Mostrar más [+] Menos [-]Comparison of Road Traffic Noise prediction models: CNOSSOS-EU, Nord2000 and TRANEX Texto completo
2021
Khan, Jibran | Ketzel, Matthias | Jensen, Steen Solvang | Gulliver, John | Thysell, Erik | Hertel, Ole
Road traffic noise is the most pervasive source of ambient outdoor noise pollution in Europe. Traffic noise prediction models vary in parameterisation and therefore may produce different estimates of noise levels depending on the geographical setting in terms of emissions sources and propagation field. This paper compares three such models: the European standard, Common Noise Assessment Methods for the EU Member States (hereafter, CNOSSOS), Nord2000 and Traffic Noise Exposure (TRANEX) model based on the UK methodology, in terms of their source and propagation characteristics. The tools are also compared by analysing estimated noise (LAₑq) from CNOSSOS, Nord2000 (2006 version), and TRANEX for more than one hundred test cases (N = 111) covering a variety of source and receiver configurations (e.g. varying source to receiver distance). The main aim of this approach was to investigate the potential pattern in differences between models’ performance for certain types of configurations. Discrepancies in performance may thus be linked to the differences in parameterisations of the CNOSSOS, Nord2000, and TRANEX (e.g. handling of diffraction, refraction). In most cases, both CNOSSOS and TRANEX reproduced LAₑq levels of Nord2000 (2006 version) within three to five dBA (CNOSSOS: 87%, TRANEX: 94%). The differences in LAₑq levels of CNOSSOS, compared to Nord2000, can be related to several shortcomings of the existing CNOSSOS algorithms (e.g. ground attenuation, multiple diffractions, and mean ground plane). The analyses show that more research is required in order to improve CNOSSOS for its implementation in the EU. In this context, amendments for CNOSSOS proposed by an EU Working Group hold significant potential. Overall, both CNOSSOS and TRANEX produced similar results, with TRANEX reproducing Nord2000 LAₑq values slightly better than the CNOSSOS. The lack of measured noise data highlights one of the significant limitations of this study and needs to be addressed in future work.
Mostrar más [+] Menos [-]Satellite evidence for pervasive water eutrophication in the Doce River reservoirs following the collapse of the Fundao dam in Brazil☆ Texto completo
2021
Coimbra, Keyla Thayrinne Oliveira | Alcântara, Enner | de Souza Filho, Carlos Roberto
One of the worst socio-environmental disasters to mark the history of Brazil and the world occurred in November 2015 and involved the mining sector. The collapse of the Fundao dam released approximately 43 million m³ of iron ore tailings, which moved downstream to reach the Doce River. This resulted in the contamination of water, soil, and sediments along the entire course of the river, which also affected its mouth in the Atlantic Ocean. Four years after the disaster, several socio-environmental problems continue to persist in the affected areas. In this context, the reservoirs built along the Doce River deserve special attention as they are artificial environments that are highly vulnerable to changes in water parameters. This study aims to determine water quality indicators of these reservoirs using remote sensing data and image processing methods, including semi-analytical algorithms, to comprehend the progress of eutrophication processes. Operational land imager/Landsat-8 data (from 2013 to 2019) were used to map the suspended particulate matter (SPM), euphotic zone (Zₑᵤ) and chlorophyll-a (Chl-a) before and after the collapse. The results showed significant changes in SPM and Zₑᵤ in the reservoirs after the collapse. Non-conformity of these parameters is observed even now, and they tend to intensify during rainy periods when resuspension processes of sediments occur. Moreover, there has been an increase in the eutrophication of reservoirs as noticed by the significant increase in Chl-a after the disaster, especially in January, July, and August.
Mostrar más [+] Menos [-]Sustainable functionalized metal-organic framework NH2-MIL-101(Al) for CO2 separation under cryogenic conditions Texto completo
2021
Bābar, Muḥammad | Mubashir, Muhammad | Mukhtar, Ahmad | Saqib, Sidra | Ullah, Sami | Bustam, Mohamad Azmi | Show, Pau Loke
In this study, a sustainable NH₂-MIL-101(Al) is synthesized and subjected to characterization for cryogenic CO₂ adsorption, isotherms, and thermodynamic study. The morphology revealed a highly porous surface. The XRD showed that NH₂-MIL-101(Al) was crystalline. The NH₂-MIL-101(Al) decomposes at a temperature (>500 °C) indicating excellent thermal stability. The BET investigation revealed the specific surface area of 2530 m²/g and the pore volume of 1.32 cm³/g. The CO₂ adsorption capacity was found to be 9.55 wt% to 2.31 wt% within the investigated temperature range. The isotherms revealed the availability of adsorption sites with favorable adsorption at lower temperatures indicating the thermodynamically controlled process. The thermodynamics showed that the process is non-spontaneous, endothermic, with fewer disorders, chemisorption. Finally, the breakthrough time of NH₂-MIL-101(Al) is 31.25% more than spherical glass beads. The CO₂ captured by the particles was 2.29 kg m⁻³. The CO₂ capture using glass packing was 121% less than NH₂-MIL-101(Al) under similar conditions of temperature and pressure.
Mostrar más [+] Menos [-]Remediation of artificially contaminated soil and groundwater with copper using hydroxyapatite/calcium silicate hydrate recovered from phosphorus-rich wastewater Texto completo
2021
Liu, Yiyang | Zhang, Rongbin | Sun, Zhenjie | Shen, Qin | Li, Yuan | Wang, Yuan | Xia, Siqing | Zhao, Jianfu | Wang, Xuejiang
Excessive copper (Cu) in contaminated soil and groundwater has attracted continuous attentions due to the bioaccumulation and durability. In this study, the feasibility of remediation of heavy metal pollution in soil and groundwater was investigated using hydroxyapatite/calcium silicate hydrate (HAP/C–S–H) recovered from phosphorus-rich wastewater in farmland. The results show that the pH has a strong effect on copper removal from Cu-contaminated groundwater but the impact of ion strength on the removal is weak. In general, high pH and low ion strength give better results in copper removal. Kinetic and isotherm data from the study fit well with Pseudo-second-order kinetic model and Langmuir isotherm model, respectively. The maximum adsorption capacity of HAP/C–S–H (138 mg/g) was higher than that of C–S–H (90.3 mg/g) when pH value, temperature, and ionic strength were 5, 308 K, and 0.01 M, respectively. Thermodynamics results indicate that Cu removal is a spontaneous and endothermic process. X-ray diffraction (XRD) results show that the mechanism of copper removal involves physical adsorption, chemical precipitation and ion exchange. For the remediation of Cu-contaminated soil, 76.3% of leachable copper was immobilized by HAP/C–S–H after 28 d. Acid soluble Cu, the main contributor to biotoxicity, decreased significantly while reducible and residual Cu increased. After immobilization, the acid neutralization capacity of the soil increased and the dissolution of copper was substantially reduced in near-neutral pH. It can be concluded that HAP/C–S–H is an effective, low-cost and eco-friendly reagent for in-situ remediation of heavy metal polluted soil and groundwater.
Mostrar más [+] Menos [-]Effect of gut microbiota on in vitro bioaccessibility of heavy metals and human health risk assessment from ingestion of contaminated soils Texto completo
2021
Yin, Naiyi | Zhao, Yongli | Wang, Pengfei | Du, Huili | Yang, Mei | Han, Zeliang | Chen, Xiaochen | Sun, Guoxin | Cui, Yanshan
To identify the role of gut microbiota in human health risk assessment, the bioaccessibility of heavy metals in 14 soil samples were determined in simulated gastrointestinal fluids. Compared to the small intestinal phase, the bioaccessibility values of the colon phase varied, either increased by 3.5-fold for As, by 2.2-fold for Cr, and by 1.6-fold for Ni, or reduced by 4.4-fold for Cu, respectively. The colon incubation with adult gut microbiota yielded higher bioaccessibility value of As (1.3 times) and Fe (3.4 times) than that of the child in most soil samples. Colon bioaccessibility was about 60% greater of Cd for the adult and 30% higher of Cr for the child. Congruent data on the bioaccessibility of Cu and Ni was observed. In addition, correlation analysis indicated that in vitro bioaccessibility was primarily related to total concentrations of heavy metals in soils, followed by soil pH and active Fe/Mn oxide. Significantly, risk assessment calculated based on colon bioaccessibility indicated that the target hazard quotient (THQ > 1) of As was presented in 3 soil samples for the adult (1.05–3.35) and in 9 soil samples for the child (1.06–26.93). The hazard index (HI) of the child was 4.00 on average, greater than that of the adult (0.62), primarily due to the contribution of As and Cd. It suggested non-carcinogenic risks are likely to occur in children through typical hand-to-mouth behavior. The adjustment of colon bioaccessibility will result in more accurate risk assessment of human exposure to heavy metals from oral ingestion of contaminated soils.
Mostrar más [+] Menos [-]Microplastics in fish meal: Contamination level analyzed by polymer type, including polyester (PET), polyolefins, and polystyrene Texto completo
2021
Castelvetro, Valter | Corti, Andrea | Bianchi, Sabrina | Giacomelli, Giacomo | Manariti, Antonella | Vinciguerra, Virginia
Fish meal (FM) is an industrial product, mainly obtained from whole wild-caught fish, that is used as a high protein feedstuff component in aquaculture and intensive animal farming. Contamination of FM by microplastics (MPs), the synthetic polymer particles known to be nearly ubiquitous in the marine environment, is a likely consequence of their ingestion by zooplankton and other small marine animals that through the food chain end up in the fish commercialized not only for direct human consumption but also for the industrial production of FM. Unfortunately, analytical tools for quantifying contamination of FM by synthetic polymers are not available. A newly developed procedure described here allows quantification of the total amounts of polyolefins (including ethene and propene homo- and copolymers), polystyrene (PS), and poly(ethylene terephthalate) (PET), respectively, in FM. The multi-step procedure involves a sequence of solvent extractions, hydrolytic treatments to remove the biogenic matrix mainly consisting of proteins and some lipids, and selective depolymerization for PET. The gravimetric and SEC-UV techniques employed for the quantification of polyolefins and PS, respectively, only allowed to estimate their concentration in FM at around or below 100 mg/kg each, a more accurate quantification being prevented by the interference from the organic matrix and, in the case of polyolefins, by the limited sensitivity of the quantification by gravimetry. On the other hand, the contamination by PET MPs could accurately be quantified at 12.9 mg/kg based on the dry FM mass. Ways to overcome the sensitivity limitations for PS and polyolefins by using e.g. pyrolysis-GC/MS are highlighted.
Mostrar más [+] Menos [-]Detection of selected tire wear compounds in urban receiving waters Texto completo
2021
Johannessen, Cassandra | Helm, Paul | Metcalfe, Christopher D.
Road runoff is an important vector for the transport of chemicals originating from tire wear into receiving waters. In this study, samples of surface water were collected in the summer of 2020 from two rivers near high-traffic corridors in the Greater Toronto Area (GTA) in Canada. These samples were analyzed for two additives used in tire production, 1,3-diphenyl guanidine (DPG) and hexamethoxymethylmelamine (HMMM), as well 26 of the transformation compounds of HMMM. In addition, samples were analyzed for 6PPD-quinone (6PPD-q), an oxidation by-product of a tire additive that was recently identified as a candidate compound responsible for mass mortalities of Coho salmon (Oncorhynchus kisutch) in spawning streams in the USA. Grab and composite samples were collected during rain events (i.e., wet events) at both locations. Grab samples were collected from the Don River upstream, downstream and at the point of discharge from a municipal wastewater treatment plant (WWTP) during a period of dry weather. Of the target analytes, 6PPD-q, DPG and HMMM, as well as 15 of the transformation compounds of HMMM, were detected at concentrations above limits of quantitation. The concentrations of 6PPD-q in the receiving waters during wet events were within the range of the LC50 for adult Coho salmon. One of the transformation products (TPs) of HMMM, dimethoxymethylmelamine was detected in a composite sample from Highland Creek at an estimated concentration greater than 10 μg/L, indicating that more research is needed to evaluate the potential hazards to the aquatic environment from this compound. Sampling in the Don River during a dry period showed that discharges of wastewater from WWTPs are also continuous sources of the TPs of HMMM. This study contributes to the growing literature showing that chemicals derived from tire wear are ubiquitous in urban watersheds and may be a significant hazard to aquatic organisms.
Mostrar más [+] Menos [-]Screening ecological risk of pesticides and emerging contaminants under data limited conditions – Case study modeling urban and agricultural watersheds with OrganoFate Texto completo
2021
Parker, Nicol | Keller, Arturo A.
The increasing number of chemicals used by society requires accessible, easy to implement tools to perform screening-level ecological risk assessments. However, field data to calibrate and validate screening tools is challenging to obtain for many watersheds. Thus, the evaluation must be done under data limited conditions. Here we employ a fate and transport model, OrganoFate, to predict environmental concentrations of contaminants of emerging concern (CECs) as well as a number of pesticides. CECs evaluated include antibacterial compounds sulfamethoxazole and triclocarban and a flame-retardant tris(1,3-dichloro-2-propyl)phosphate (TDCPP). We also evaluated widely used pesticides chlorpyrifos, bifenthrin and esfenvalerate. We predict concentrations of the contaminants in high-risk watersheds which were dominated by either urban or agricultural development and have small aquatic compartments. Screening-level predictions were in good agreement with observed concentrations in surface water and sediment. Maximum predicted concentrations were close to the highest observed concentrations for CECs, only ~0.1 μg/L greater for sulfamethoxazole and triclocarban concentrations, and for TDCPP <5 μg/L higher. ChemFate was also employed to screen possible aquatic health impacts. Results demonstrated possible CEC aquatic health risk for TDCPP and triclocarban (risk quotients of 0.9 and 1.1 respectively). For pesticides, exceedance of effect (EC50) and lethal (LC50) endpoints was predicted for various taxonomic groups which include aquatic invertebrates, fish, amphibians, and benthic organisms.
Mostrar más [+] Menos [-]Pilot study on the urinary excretion of the glyphosate metabolite aminomethylphosphonic acid and breast cancer risk: The Multiethnic Cohort study Texto completo
2021
Franke, Adrian A. | Li, Xingnan | Shvetsov, Yurii B. | Lai, Jennifer F.
Breast cancer is the most commonly diagnosed female cancer and the second leading cause of death in women in the US, including Hawaii. Accumulating evidence suggests that aminomethylphosphonic acid (AMPA), the primary metabolite of the herbicide glyphosate—a probable human carcinogen, may itself be carcinogenic. However, the relationship between urinary AMPA excretion and breast cancer risk in women is unknown. In this pilot study, we investigated the association between pre-diagnostic urinary AMPA excretion and breast cancer risk in a case-control study of 250 predominantly postmenopausal women: 124 cases and 126 healthy controls (individually matched on age, race/ethnicity, urine type, date of urine collection, and fasting status) nested within the Hawaii biospecimen subcohort of the Multiethnic Cohort. AMPA was detected in 90% of cases and 84% of controls. The geometric mean of urinary AMPA excretion was nearly 38% higher among cases vs. controls (0.087 vs 0.063 ng AMPA/mg creatinine) after adjusting for race/ethnicity, age and BMI. A 4.5-fold higher risk of developing breast cancer in the highest vs. lowest quintile of AMPA excretion was observed (ORQ₅ ᵥₛ. Q₁: 4.49; 95% CI: 1.46–13.77; pₜᵣₑₙd = 0.029). To our knowledge, this is the first study to prospectively examine associations between urinary AMPA excretion and breast cancer risk. Our preliminary findings suggest that AMPA exposure may be associated with increased breast cancer risk; however, these results require confirmation in a larger population to increase study power and permit careful examinations of race/ethnicity differences.
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