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1.
Sci Total Environ ; 904: 166368, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37619721

ABSTRACT

Clean technologies are rapidly increasing in the last decade. In the transport sector, market share of global electric car sales has changed from 0.0 % in 2010 to 3.2 % (2.1million) in 2020, and predictions show that sales could reach near 30 % in 2030. This drastic change is mainly encouraged by environmental goals set to reduce greenhouse gas emissions (GHG) expressed in CO2-eq, not emitted by electric vehicles (EVs) during the use phase. However, clean technologies might cause other impacts during manufacture and, while clearly reduce the dependency on oil, can increase the dependency on other materials. In this context, the objectives of our work are quantifying the critical raw materials needed by permanents magnets and batteries of EVs (neodymium, lithium, and cobalt); their supply risk, performing a material flow analysis; and studying their environmental impacts using the methodology "Environmentally-Extended Multi-Regional Input-Output Analysis". This methodology is used to quantify the produced impacts and the country where the impacts are being produced, in contrast to conventional methodologies that only calculate global impacts. Therefore, environmental impacts are estimated considering different scenarios, based on environmental objectives of the European Union and China. In most scenarios China shows a key role in mining and processing of metals, being the country where major impacts are produced. Obtained results are useful to assess which environmental proposals are more effective to reduce the environmental impact of EVs and set the ground to understand the geostrategic importance of key metals used for EVs manufacture.

2.
Dialect Anthropol ; 47(1): 33-43, 2023.
Article in English | MEDLINE | ID: mdl-36820012

ABSTRACT

This paper explores the connections between the culture and living conditions of Afro-descendants in Colombian society. The specific object of study is Champeta, a Black urban music associated with social resistance. The text analyzes Champeta's evolution in Colombia's multicultural frame. It concludes with an analysis of these multicultural premises' shortcomings, especially regarding the material improvement of Black Colombians' living conditions. This text contributes to current debates on cultural diversity in Latin America.

3.
Ecotoxicol Environ Saf ; 224: 112629, 2021 Aug 14.
Article in English | MEDLINE | ID: mdl-34399125

ABSTRACT

Mining operations are important causes of environmental pollution in developing countries where mining waste management is not adequate. Consequently, heavy metal(loid)s are easily released into the environment, being a potential risk to human health. This study carries out a Bayesian probabilistic human health risk assessment, related to multi-pathway exposure to heavy metal(loid)s in a gold mining area in Southern Ecuador. Concentrations of As, Cd, Cr, Cu, Ni, Pb, and Zn in tap water, surface water, and soil samples, were analyzed to assess the potential adverse human health effects based on the Hazard Index (HI) and Total cancer risk (TCR). Adults and children residents were surveyed to adjust their exposure parameters to the site-specific conditions. Exposure to heavy metal(loid)s resulted in unacceptable risk levels for human health in the two age groups, both carcinogenic (TCR > 1 × 10-5) and non-carcinogenic (HI > 1) through ingestion of tap water and incidental ingestion of surface water. Sensitivity analysis showed that As concentration in waters and exposure frequency were the main contributors to risk outcome. Exposure to soil via accidental ingestion and dermal contact was below the safety limit, not posing a risk to human health. These findings can provide a baseline for the environmental management of the mining area and indicate the need for further research on As pollution in water and its implications on the health of the inhabitants of mining communities.

4.
Environ Geochem Health ; 43(11): 4459-4474, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33881675

ABSTRACT

Gold mining is a significant source of metal(loid)s released into the environment. It is an issue of concern due to the potential adverse health effects associated with exposure to toxic elements. This study aimed to assess the ecological and human health risk caused by heavy metal(loid)s exposure in river sediments in Ponce Enríquez, one of the most important mining sites in Ecuador. Concentrations of As, Cd, Cu, Pb, and Zn were evaluated in 172 sediment samples to determine the Potential ecological risk (RI) and the carcinogenic (CR) and non-carcinogenic risk (HQ). The human exposure to polluted sediments during recreational activities was computed using Bayesian probabilistic models. Residents were randomly surveyed to adjust the risk models to the specific population data. More than 68% of the sampling stations pose a severe As and Cd ecological risk index ([Formula: see text] > 320). Likewise, residents exposed to river sediments showed a non-acceptable carcinogenic risk by incidental ingestion, being As the primary contributor to overall cancer in both children and adults receptors. Moreover, non-carcinogenic risk through the incidental ingestion of sediments was above the safe limit for children. This is the first study conducted in a mining region in Ecuador that reveals the severe levels of ecological and human health risk to which the population is exposed. These results can be applied as a baseline to develop public health strategies to monitor and reduce the health hazards of the residents of mining communities.


Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Adult , Bayes Theorem , Child , China , Ecuador , Environmental Monitoring , Geologic Sediments , Humans , Metals, Heavy/analysis , Metals, Heavy/toxicity , Risk Assessment , Rivers , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
5.
Waste Biomass Valorization ; 12(5): 2303-2310, 2021.
Article in English | MEDLINE | ID: mdl-32837664

ABSTRACT

ABSTRACT: In Europe, recent regulations on advanced biofuels have prompted a search for new fuel sources and the development of synthesis methods meeting the demanding specifications of the sector. However, in developing countries such as Algeria, where a significant stock of frying oil is unused, the use of diesel engines powered with waste-oil-derived biofuels must be explored. In this work, the variables related to the transesterification reaction from this frying oil with ethanol are analyzed using response surface methodology. From this analysis, only the reaction time and temperature have been determined as relevant parameters. In addition, FT-IR analysis has proven a useful tool to analyse the conversion in the transesterification reaction of waste frying oil with ethanol and is cheaper and quicker than GC-FID. This sustainable biofuel (FAEE), mixed with a diesel and pure fuel, has been physically characterized. The mixture of FAEE at 30% by volume with diesel meets the requirements demanded in standard EN 590 and can be classified as winter diesel class D. As a pure biofuel, only its high cold flow temperatures could constitute a drawback for exporting to temperate climates but not for internal consumption.

6.
J Environ Manage ; 273: 111139, 2020 Nov 01.
Article in English | MEDLINE | ID: mdl-32768761

ABSTRACT

Potentially toxic elements (PTEs) present in abandoned mining wastes (AMW) are of great concern because of potential risks to human health and ecosystems. Indices of contamination (IC) applied to mining wastes are calculated using the total concentration of PTEs and comparing them with regional geochemical backgrounds. However, determining the total content of heavy metals is insufficient to assess the hazard of mining wastes. Therefore, in addition to total concentration, the potential risk is also evaluated through water mobility of elements. Accordingly, leaching procedures are useful tools for the geochemical characterization of soluble constituents that are mobilized. In this study, the solubility of PTEs from different types of mining wastes is comparatively assessed using three standard leaching methods (European; U.S. Geological Survey and; Mexican). The Hazard Average Quotient (HAQ) was calculated to assess the potential Toxicity Factor (TF). TF is an indicator of the relative potential toxicity of wastes and is the basis for the classification of AMW. A comparative assessment provides evidence that there are no statistically significant differences in PTEs solubility by the three leaching methods and it was also found that the pH of the eluates was dictated by the type of waste. Results suggest that the IC gives an indicator of the potential contamination of soils and sediments by erosive processes, or a long-term measure, whereas TF assesses the possibility of contaminating water in the short term. The most significant finding is the new ranking scale of TF, as a function of HAQ, applied to the Mexican standard leaching test. This factor, together with other considerations relating to risk-generating processes, might then be applied in places having large amounts of recorded AMW, such as the Iberian Peninsula and Latin America, where effective management is required to rank sites, based on preliminary environmental and human risk assessment.


Subject(s)
Metals, Heavy/analysis , Soil Pollutants/analysis , Ecosystem , Environmental Monitoring , Humans , Mexico , Mining
7.
Ecotoxicol Environ Saf ; 201: 110833, 2020 Sep 15.
Article in English | MEDLINE | ID: mdl-32535368

ABSTRACT

The largest mercury (Hg) mining district in the world is located in Almadén (Spain), with well-known environmental impacts in the surrounding ecosystem. However, the impact of mercury on the health of the inhabitants of this area has not been documented accordingly. This study aims to carry out a probabilistic human health risk assessment using Bayesian modeling to estimate the non-carcinogenic risk related to Hg through multiple exposure pathways. Samples of vegetables, wild mushrooms, fish, soil, water, and air were analyzed, and adult residents were randomly surveyed to adjust the risk models to the specific population data. On the one hand, the results for the non-carcinogenic risk based on Hazard Quotient (HQ) showed unacceptable risk levels through ingestion of Hg-contaminated vegetables and fish, with HQ values 20 and 3 times higher, respectively, than the safe exposure threshold of 1 for the 97.5th percentile. On the other hand, ingestion of mushrooms, dermal contact with soil, ingestion of water, dermal contact with water and inhalation of air, were below the safety limit for the 97.5th percentile, and did not represent a risk to the health of residents. In addition, the probabilistic approach was compared with the conservative deterministic approach, and similar results were obtained. This is the first study conducted in Almadén, which clearly reveals the high levels of human health risk to which the population is exposed due to the legacy of two millennia of Hg mining.


Subject(s)
Environmental Exposure/analysis , Environmental Pollutants/analysis , Mercury/analysis , Mining , Adult , Agaricales/chemistry , Air/analysis , Animals , Bayes Theorem , Ecosystem , Fishes/metabolism , Humans , Random Allocation , Risk Assessment , Soil/chemistry , Spain , Vegetables/chemistry
8.
Sci Total Environ ; 686: 580-589, 2019 Oct 10.
Article in English | MEDLINE | ID: mdl-31185405

ABSTRACT

The purpose of this research is to find a mathematical model based on a statistical analysis to predict the evolution of the total petroleum hydrocarbons (TPH) concentrations with time in the bioremediation process of diesel contaminated soils. The analysis is useful to compare and ascertain the efficiency of different remediation treatments and the influence of both soil characteristics and initial concentration levels of hydrocarbons on the biodegradation process. An experimental design, considering two types of soil, two concentration levels of hydrocarbons and six different amendments was carried out. A total of 336 laboratory tests were conducted during a year in 48 land plots of 4×4m, spreading over eight field campaigns. The results show, for the first time to the best of our knowledge, that the bioremediation process can be adjusted quantitatively to an exponential model, following a first-order kinetic equation. The model explains correctly the higher efficiency of some treatments. In the case of hydrocarbon concentrations <16,000mg/kg, it is advisable to use slow-release fertilizer without the use of surfactant; whereas, for concentrations above 30,000mg/kg, the addition of surfactants improves the results considerably.


Subject(s)
Biodegradation, Environmental , Petroleum/analysis , Soil Pollutants/analysis , Linear Models , Petroleum/metabolism , Soil Pollutants/metabolism
9.
Environ Sci Pollut Res Int ; 25(29): 29468-29480, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30132284

ABSTRACT

The overall objective of this study is to estimate, detect and specify the main sources of variance which affect the contents of the different elements in overbank sediments across Spain. These sources of variance were assessed and compared by means of a series of analyses of variance (ANOVAs), by regarding two parameters: their significance and their contribution to the total variance. Overbank sediments, sampled in erosion banks, were studied in several locations, in basins which drain different types of geological backgrounds and land uses (urban, mining, agricultural or pristine) across the Iberian Peninsula. Forty-eight elements (mostly in the < 63 µm fraction) were analysed by ICP-OES, ICP-MS and INAA. After an isometric log ratio (ilr) transformation of the data, three ANOVA analyses were performed considering three perspectives: (1) local scale, (2) regional scale: within-profile perspective and (3) regional scale: inter-profile perspective. On a local scale, it was observed that the variability of rare earth elements (REE) depends mostly on the grain size and that heavy metals are also influenced by depth. In the analysis carried out on a regional scale, from a within-profile perspective, depth and duplicates do not influence significantly the variability of the element contents. Finally, from an inter-profile perspective, the selected sources of variance were land use and provenance, whose significance is the highest. While grain size and the selection of depth are of crucial importance in the final results, on local studies, land use and provenance are the ones that influence the most the composition of sediments in regional studies.


Subject(s)
Environmental Monitoring/statistics & numerical data , Geologic Sediments/analysis , Geology/statistics & numerical data , Metals, Heavy/analysis , Metals, Rare Earth/analysis , Agriculture , Cities , Environmental Monitoring/methods , Environmental Pollutants/analysis , Geologic Sediments/chemistry , Geology/methods , Mining , Spain
10.
Sci Total Environ ; 586: 446-456, 2017 May 15.
Article in English | MEDLINE | ID: mdl-28215803

ABSTRACT

Polycyclic Aromatic Hydrocarbons (PAHs) are pollutants of concern due to their carcinogenic and mutagenic activity. Their emissions are mainly related with the combustion or pyrolysis of the organic matter, such as in fossil fuels combustion. It is important to characterize PAHs in the combustions of biofuels due to their increasing importance in the actual energetic setting. There is a lot of research focused in PAHs emission due to the combustion in diesel engines; but only few of them have analyzed the effect of raw material and type of alcohol used in the transesterification process. Different raw materials (i.e. animal fat, palm, rapeseed, linseed, peanut, coconut, and soybean oils) have been used for obtaining FAME and FAEE. A method for measuring PAHs generated during combustion in a bomb calorimeter has been developed. Combustion was made at different oxygen pressures and the samples were taken from the bomb after each combustion. Samples were extracted and the PAHs amounts formed during combustion were analyzed by GC-MS. This research shows the statistical relationships among the 16 PAHs of concern, biodiesel composition and oxygen pressure during combustion.

11.
Transgenic Res ; 24(1): 43-60, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25011563

ABSTRACT

The fungi Botrytis cinerea and Erysiphe necator are responsible for gray mold and powdery mildew diseases, respectively, which are among the most devastating diseases of grapes. Two endochitinase (ech42 and ech33) genes and one N-acetyl-ß-D-hexosaminidase (nag70) gene from biocontrol agents related to Trichoderma spp. were used to develop a set of 103 genetically modified (GM) 'Thompson Seedless' lines (568 plants) that were established in open field in 2004 and evaluated for fungal tolerance starting in 2006. Statistical analyses were carried out considering transgene, explant origin, and plant response to both fungi in the field and in detached leaf assays. The results allowed for the selection of the 19 consistently most tolerant lines through two consecutive years (2007-2008 and 2008-2009 seasons). Plants from these lines were grafted onto the rootstock Harmony and established in the field in 2009 for further characterization. Transgene status was shown in most of these lines by Southern blot, real-time PCR, ELISA, and immunostrips; the most tolerant candidates expressed the ech42-nag70 double gene construct and the ech33 gene from a local Hypocrea virens isolate. B. cinerea growth assays in Petri dishes supplemented with berry juices extracted from the most tolerant individuals of the selected population was inhibited. These results demonstrate that improved fungal tolerance can be attributed to transgene expression and support the iterative molecular and physiological phenotyping in order to define selected individuals from a population of GM grapevines.


Subject(s)
Chitinases/genetics , Disease Resistance/genetics , Plants, Genetically Modified/genetics , beta-N-Acetylhexosaminidases/genetics , Botrytis/pathogenicity , Gene Transfer Techniques , Plant Diseases/genetics , Plants, Genetically Modified/growth & development , Plants, Genetically Modified/microbiology , Trichoderma/enzymology , Trichoderma/genetics , Vitis/genetics , Vitis/growth & development , Vitis/microbiology
12.
Chemosphere ; 108: 183-9, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24534152

ABSTRACT

Colombia is one of the largest per capita mercury polluters in the world as a consequence of its artisanal gold mining activities. The severity of this problem in terms of potential health effects was evaluated by means of a probabilistic risk assessment carried out in the twelve departments (or provinces) in Colombia with the largest gold production. The two exposure pathways included in the risk assessment were inhalation of elemental Hg vapors and ingestion of fish contaminated with methyl mercury. Exposure parameters for the adult population (especially rates of fish consumption) were obtained from nation-wide surveys and concentrations of Hg in air and of methyl-mercury in fish were gathered from previous scientific studies. Fish consumption varied between departments and ranged from 0 to 0.3 kg d(-1). Average concentrations of total mercury in fish (70 data) ranged from 0.026 to 3.3 µg g(-1). A total of 550 individual measurements of Hg in workshop air (ranging from


Subject(s)
Environmental Exposure , Mercury/analysis , Mining , Air Pollutants/analysis , Colombia , Gold , Humans , Methylmercury Compounds/analysis , Risk Assessment , Seafood , Spectrophotometry, Atomic , Water Pollutants, Chemical/analysis
13.
Electron. j. biotechnol ; 15(4): 8-8, July 2012. ilus, tab
Article in English | LILACS | ID: lil-646958

ABSTRACT

Deschampsia antarctica (DA), the only species in the Gramineae family endemic to the Antarctic territory, is characterized by a combination of high levels of free endogenous phenylpropanoid compounds under normal in situ and in vitro growth conditions. In this article, we describe the design and use of a specific temporary immersion photobioreactor to produce both increased DA biomass and secondary metabolite accumulation by UV-B elicitation during cultivation. Three min-long immersions in an induction medium applied every 4 hrs at 14ºC +/- 1 and 20/4 hrs light/darkness photoperiod increased DA biomass production over previous in vitro reports. Biomass duplication was obtained at day 10.7 of culturing, and maximum total phenolics and antioxidant activity were observed after 14 day of culturing. The addition of UV-B radiation pulses for 0.5 hrs at 6 hrs intervals increased total phenolics and antioxidant activity more than 3- and 1.5- fold, respectively, compared to controls with no UV-B. Significant accumulation of scopoletin, chlorogenic acid, gallic acid and rutin was found in these plantlets. This is the first bioreactor designed to optimize biomass and phenylpropanoid production in DA.


Subject(s)
Phenols/metabolism , Poaceae/radiation effects , Poaceae/metabolism , Bioreactors , Ultraviolet Rays
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