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Human Health Risk Assessment of CO2: Survivors of Acute High-Level Exposure and Populations Sensitive to Prolonged Low-Level Exposure

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... Severe health effects of CO 2 only occur under extremely high concentrations. In 1986, at Lake Nyos in Cameroon multiple people died due to an exposure to estimated CO 2 concentrations of 8-10% (i.e., 80 000 -100 000 ppm) (Rice, 2014); this concentration was caused by a sudden outgassing of CO 2 stored in the lake. Rice (2014) reports other adverse health effects, such as decreased lung functioning, from 8500 ppm. ...
... In 1986, at Lake Nyos in Cameroon multiple people died due to an exposure to estimated CO 2 concentrations of 8-10% (i.e., 80 000 -100 000 ppm) (Rice, 2014); this concentration was caused by a sudden outgassing of CO 2 stored in the lake. Rice (2014) reports other adverse health effects, such as decreased lung functioning, from 8500 ppm. Such high levels, however, generally not occur when the primary source is human respiration. ...
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Students in a country like Ethiopia face a double air pollution challenge: they are frequently exposed (both outdoors and indoors) to sources of incomplete combustion and therefore to unhealthy concentrations of particulate matter (PM2.5) and carbon monoxide (CO), while they also face increased carbon dioxide (CO2) concentrations in crowded dormitories and classrooms. Research on air pollution in the environment of Ethiopian students is scarce. This lack of research can be fixed by involving students in science through a student science project, essentially a subset of citizen science. Students of Arba Minch University, Ethiopia, conducted measurements of PM2.5, CO, and CO2 under self-selected circumstances. Their measurements are compared to guideline values related to health effects to identify priority areas for future research. For PM2.5, students’ measurements show likely exceedances of guideline values for an inside coffee ceremony, close to open waste burning, at a bus station and close to a diesel generator. For CO, exceedances are revealed in kitchens and the visitor’s area of restaurants using biomass fuel, close to outdoor charcoal cooking and close to waste burning. For CO2, exceedances are found within student dormitories. These areas can be considered priority areas for further research. Students can conduct additional measurements to distinguish other relevant scenarios. Insight into exposure can be improved if, besides different concentrations under different circumstances, also time durations of these different circumstances are studied. The findings reveal that students themselves can be a partial solution to research and resource gaps in their context.
... Hacquemand et al. (2010) and Martrette et al. (2017) found that long-term exposure to 700 ppm CO 2 will cause physiological dysfunction through animal experiments. Rice (2014) and Schaefer (1982) pointed out that long-term exposure to CO 2 can decrease attention, which ultimately leads to a decrease in the body's coordination and resistance. In fact, the increase in CO 2 concentration does not need to be significant (compared to the volume of other gases), but causes slight mechanical discomfort in the body. ...
... In fact, the increase in CO 2 concentration does not need to be significant (compared to the volume of other gases), but causes slight mechanical discomfort in the body. The human lung cavity may change significantly when CO 2 concentration reaches 0.85% in the air, and the blood pressure and flow in the brain will be abnormally higher when the concentration reaches 1.20% (Gall et al., 2016;Rice, 2014). ...
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Excessive greenhouse gas emissions might be the major culprit for environmental degradation, which have direct and indirect adverse impacts in various ways. As the largest emitter of carbon emissions, China suffered great harm from climate change during the past 40 years. Therefore, it becomes necessary to study the impact of carbon emissions on health issues and their potential mechanism. Using the panel data from 30 provinces in China between 2002 and 2017, this study employes and extends the Stochastic Impacts by Regression on Population, Affluence, and Technology (STIRPAT) model and mediating effect model to analyze the direct and indirect effects of carbon emissions. The main results are as follows: (1) Carbon emissions has a certain negative impact on public health, which would increase with the rise of temperature. (2) The increase in carbon emissions has a more significant negative effect on health with the average temperature exceeding 17.75 °C, indicating that the temperature has a threshold effect. (3) The potential health risks become higher with the development of urbanization, but there is no obvious spillover effect in the health consequences. The results remain robust after controlling other factors. This study supplements the literature of climate governance and human health, potentially contributing to the next stage of high-quality and sustainable development.
... Dato que ha provocado que se realicen esfuerzos conjuntos entre los países más desarrollados y se propongan decisiones para resolver este problema. Sin embargo, para tomar decisiones eficaces fue necesario primero tomar acciones de monitoreo de gases, lo que originó que la primera década del siglo XXI fuera denominada la "década del sensor" (Wilson, 2004;Rice, 2004;Bogue, 2008). ...
... One-hour exposure of~25 ppb NO 2 is associated with 1.3% increase in the daily number of deaths [26]. The effects of high-level CO 2 exposure are physiologic, toxic, and potentially lethal [27]. CO 2 levels should not exceed 1000 ppm [28]. ...
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... Dato que ha provocado que se realicen esfuerzos conjuntos entre los países más desarrollados y se propongan decisiones para resolver este problema. Sin embargo, para tomar decisiones eficaces fue necesario primero tomar acciones de monitoreo de gases, lo que originó que la primera década del siglo XXI fuera denominada la "década del sensor" (Wilson, 2004;Rice, 2004;Bogue, 2008). ...
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