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A new method to measure real-world respiratory tract deposition of inhaled ambient black carbon
2019
Madueño, Leizel | Kecorius, Simonas | Löndahl, Jakob | Müller, Thomas | Pfeifer, Sascha | Haudek, Andrea | Mardoñez, Valeria | Wiedensohler, Alfred
In this study, we present the development of a mobile system to measure real-world total respiratory tract deposition of inhaled ambient black carbon (BC). Such information can be used to supplement the existing knowledge on air pollution-related health effects, especially in the regions where the use of standard methods and intricate instrumentation is limited. The study is divided in two parts. Firstly, we present the design of portable system and methodology to evaluate the exhaled air BC content. We demonstrate that under real-world conditions, the proposed system exhibit negligible particle losses, and can additionally be used to determine the minute ventilation. Secondly, exemplary experimental data from the system is presented. A feasibility study was conducted in the city of La Paz, Bolivia. In a pilot experiment, we found that the cumulative total respiratory tract deposition dose over 1-h commuting trip would result in approximately 2.6 μg of BC. This is up to 5 times lower than the values obtained from conjectural approach (e.g. using physical parameters from previously reported worksheets). Measured total respiratory tract deposited BC fraction varied from 39% to 48% during walking and commuting inside a micro-bus, respectively.To the best of our knowledge, no studies focusing on experimental determination of real-world deposition dose of BC have been performed in developing regions. This can be especially important because the BC mass concentration is significant and determines a large fraction of particle mass concentration. In this work, we propose a potential method, recommendations, as well as the limitations in establishing an easy and relatively cheap way to estimate the respiratory tract deposition of BC.
Afficher plus [+] Moins [-]Air Quality Standards for Particulate Matter (PM) at high altitude cities
2013
Bravo Alvarez, H. | Sosa Echeverria, R. | Sanchez Alvarez, P. | Krupa, S.
The Air Quality Standards for Particulate Matter (PM) at high altitude urban areas in different countries, must consider the pressure and temperature due to the effect that these parameters have on the breath volume.This paper shows the importance to correct Air Quality Standards for PM considering pressure and temperature at different altitudes. Specific factors were suggested to convert the information concerning PM, from local to standard conditions, and adjust the Air Quality Standards for different high altitudes cities. The correction factors ranged from: 1.03 for Santiago de Chile to 1.47 for El Alto Bolivia. Other cities in this study include: Mexico City, México; La Paz, Bolivia; Bogota, Cali and Medellin, Colombia; Quito, Ecuador and Cuzco, Peru.If these corrections are not considered, the atmospheric concentrations will be underestimated.
Afficher plus [+] Moins [-]Mercury contamination level and speciation inventory in Lakes Titicaca & Uru-Uru (Bolivia): Current status and future trends
2017
Guédron, S. | Point, D. | Acha, D. | Bouchet, S. | Baya, P.A. | Tessier, E. | Monperrus, M. | Molina, C.I. | Groleau, A. | Chauvaud, L. | Thebault, J. | Amice, E. | Alanoca, L. | Duwig, C. | Uzu, G. | Lazzaro, X. | Bertrand, A. | Bertrand, S. | Barbraud, C. | Delord, K. | Gibon, F.M. | Ibanez, C. | Flores, M. | Fernandez Saavedra, P. | Ezpinoza, M.E. | Heredia, C. | Rocha, F. | Zepita, C. | Amouroux, D.
Aquatic ecosystems of the Bolivian Altiplano (∼3800 m a.s.l.) are characterized by extreme hydro-climatic constrains (e.g., high UV-radiations and low oxygen) and are under the pressure of increasing anthropogenic activities, unregulated mining, agricultural and urban development. We report here a complete inventory of mercury (Hg) levels and speciation in the water column, atmosphere, sediment and key sentinel organisms (i.e., plankton, fish and birds) of two endorheic Lakes of the same watershed differing with respect to their size, eutrophication and contamination levels. Total Hg (THg) and monomethylmercury (MMHg) concentrations in filtered water and sediment of Lake Titicaca are in the lowest range of reported levels in other large lakes worldwide. Downstream, Hg levels are 3–10 times higher in the shallow eutrophic Lake Uru-Uru than in Lake Titicaca due to high Hg inputs from the surrounding mining region. High percentages of MMHg were found in the filtered and unfiltered water rising up from <1 to ∼50% THg from the oligo/hetero-trophic Lake Titicaca to the eutrophic Lake Uru-Uru. Such high %MMHg is explained by a high in situ MMHg production in relation to the sulfate rich substrate, the low oxygen levels of the water column, and the stabilization of MMHg due to abundant ligands present in these alkaline waters. Differences in MMHg concentrations in water and sediments compartments between Lake Titicaca and Uru-Uru were found to mirror the offset in MMHg levels that also exist in their respective food webs. This suggests that in situ MMHg baseline production is likely the main factor controlling MMHg levels in fish species consumed by the local population. Finally, the increase of anthropogenic pressure in Lake Titicaca may probably enhance eutrophication processes which favor MMHg production and thus accumulation in water and biota.
Afficher plus [+] Moins [-]High altitude artisanal small-scale gold mines are hot spots for Mercury in soils and plants
2013
Terán-Mita, Tania A. | Faz, Angel | Salvador, Flor | Arocena, Joselito M. | Acosta, Jose A.
Mercury releases from artisanal and small-scale gold mines (ASGM) condense and settle on plants, soils and water bodies. We collected soil and plant samples to add knowledge to the likely transfer of Hg from soils into plants and eventually predict Hg accumulation in livestock around ASGM in Bolivia. Mean contents of Hg in soils range from 0.5 to 48.6 mg Hg kg−1 soil (5× to 60× more compared to control sites) and exceeded the soil Hg threshold levels in some European countries. The Hg contents ranged from 0.6 to 18 and 0.2 to 28.3 mg Hg kg−1 leaf and root, respectively. The high Hg in Poaceae and Rosaceae may elevate Hg accumulation into the food chain because llama and alpaca solely thrive on these plants for food. Erosion of soils around ASGM in Bolivia contributes to the Hg contamination in lower reaches of the Amazon basin.
Afficher plus [+] Moins [-]Indoor metallic pollution related to mining activity in the Bolivian Altiplano
2011
Fontúrbel, Francisco E. | Barbieri, Enio | Herbas, Cristian | Barbieri, Flavia L. | Gardon, Jacques
The environmental pollution associated with mining and metallurgical activities reaches its greatest extent in several Andean cities and villages. Many locations in this area have accumulated through centuries a large amount of mining wastes, often disregarding the magnitude of this situation. However, in these naturally mineralized regions, there is little information available stating the exact role of mining and metallurgical industries in urban pollution. In this study, we demonstrated that the various metallic elements present in indoor dust (As, Cd, Cu, Pb, Sb, Sn, Zn) had a common origin and this contamination was increased by the proximity to the mines. Lead dust concentration was found at concerning levels for public health. In addition, wrong behaviors such as carrying mining workwear home contributed to this indoor dust pollution. Consequently, the constant exposure of the population could represent a potential health hazard for vulnerable groups, especially children.
Afficher plus [+] Moins [-]Consumption-based carbon emissions, trade, and globalization: an empirical study of Bolivia
2022
Kirikkaleli, Dervis | Oyebanji, Modupe Oluyemisi
The consequences of global trade on carbon dioxide emissions have been mainly investigated in several empirical papers; however, the consumption-based carbon emissions adjusted for international trade have been lacking in the literature. This empirical research seeks to address this gap by using consumption-based carbon emissions adjusted for trade in the case of Bolivia. Research over the years shows that Bolivia has had a consistent negative trade deficit which suggests that there might be a rise in consumption-based emission in this area in the present and the future. It also indicates that considerable emissions are attributable to the consumption of commodities and services transferred to Bolivia, which is beyond its control. Many studies, however, have delved into the production-based carbon emission for Bolivia. However, the consumption-based carbon emission adjusted for international trade has been missing in the case of Bolivia. Meanwhile, failure to recognize these emissions related to international trade produces an incomplete picture of the emissions triggers and the effectiveness of action to lessen emissions in this area. Hence, this study attempts to fill the gap. The impact of exports and imports are analyzed separately for 1970 to 2018. The empirical analysis confirms a negative effect of exports and GDP on consumption-based carbon emissions. In comparison, imports and globalization demonstrate a favorable impact on consumption-based carbon emissions and show their statistical significance. This study suggests that the Bolivia government should be cautious on policies targeted at increasing growth as this could be harmful to the sustainability of the environment.
Afficher plus [+] Moins [-]How Uncontrolled Urban Expansion Increases the Contamination of the Titicaca Lake Basin (El Alto, La Paz, Bolivia)
2017
Archundia, D. | Duwig, C. | Spadini, L. | Uzu, G. | Guédron, S. | Morel, M. C. | Cortez, R. | Ramos Ramos, O. | Chincheros, J. | Martins, J. M. F.
Cities in developing countries encounter rapid waves of social transformation and economic development where the environment is mostly a neglected aspect. The Katari watershed encompasses mining areas, El Alto city (one of the fastest growing urban areas in South America and the biggest in the Altiplano) as well as agricultural areas. Its outlet is Cohana Bay, one of the most polluted areas of Lake Titicaca. Here we propose an integrative approach (hydrological, physicochemical, chemical and bacterial data) to understand the pollution problem of this developing area, in which a variety of anthropogenic activities takes place. Both mining and urban areas appear to be sources of metal pollution. Nutrient and bacterial contaminations are mainly related to urban and industrial discharges. These situations have impacts in the basin from the mining area down to Cohana Bay of Lake Titicaca. Pollutant concentration patterns are highly influenced by seasonal hydrology variations. The poor quality of surface waters in the basin represents a risk for human and animal populations, as well as for the quality of aquifers located underneath El Alto city.
Afficher plus [+] Moins [-]Greenhouse gas emissions, non-renewable energy consumption, and output in South America: the role of the productive structure
2020
Deng, Qiushi | Alvarado, Rafael | Toledo, Elisa | Caraguay, Leidy
Most of the countries of South America depend heavily on mining and agriculture, which develops through the destruction of the forest. The expansion of the agricultural frontier is more visible in countries with proximity to the Amazon. Otherwise, the increase in urban primacy and real income per capita has led to an increase in the use of non-renewable energy in recent decades. The interest in quantifying greenhouse gas emissions has increased, oriented towards the search for mechanisms that mitigate the irreversible effects of climate change. In this context, the objective of this research is to examine the causal link among non-renewable energy consumption and real GDP per capita in greenhouse gas emissions in ten countries of South America during 1971–2014. In addition, we group the countries according to their productive structure and we incorporate the structural changes of each country in the econometric estimations, allowing to significantly improve the understanding of the sources of greenhouse gases. We use cointegration and causality techniques for time series data, and we found that there is a relationship of short- and long-term equilibrium between the three variables in all countries. The causality test indicates that in Bolivia, Peru, and Uruguay, there is causality from the consumption of non-renewable energy to greenhouse gas emissions. Likewise, in Venezuela and the agricultural countries, GDP causes greenhouse gas emissions. An implication of the public policy derived from this research is that most of the countries of South America can promote a change in the energy matrix to contribute to the mitigation of greenhouse gas emissions without limiting economic growth.
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