Pharmaceutical pollution of the world's rivers

Environmental exposure to active pharmaceutical ingredients (APIs) can have negative effects on the health of ecosystems and humans. While numerous studies have monitored APIs in rivers, these employ different analytical methods, measure different APIs, and have ignored many of the countries of the world. This makes it difficult to quantify the scale of the problem from a global perspective. Furthermore, comparison of the existing data, generated for different studies/regions/continents, is challenging due to the vast differences between the analytical methodologies employed. Here, we present a global-scale study of API pollution in 258 of the world's rivers, representing the environmental influence of 471.4 million people across 137 geographic regions. Samples were obtained from 1,052 locations in 104 countries (representing all continents and 36 countries not previously studied for API contamination) and analyzed for 61 APIs. Highest cumulative API concentrations were observed in sub-Saharan Africa, south Asia, and South America. The most contaminated sites were in low- to middle-income countries and were associated with areas with poor wastewater and waste management infrastructure and pharmaceutical manufacturing. The most frequently detected APIs were carbamazepine, metformin, and caffeine (a compound also arising from lifestyle use), which were detected at over half of the sites monitored. Concentrations of at least one API at 25.7% of the sampling sites were greater than concentrations considered safe for aquatic organisms, or which are of concern in terms of selection for antimicrobial resistance. Therefore, pharmaceutical pollution poses a global threat to environmental and human health, as well as to delivery of the United Nations Sustainable Development Goals

Observations of cold electrons by RPC-MIP at 67P/Churuymov-Gerasimenko

International audienceThe Mutual Impedance Probe (MIP) of the Rosetta Plasma Consortium (RPC) onboard the Rosetta orbiter operated during more than two years from August 2014 to September 2016 in order to measure the electron density in the cometary ionosphere of 67P/Churyumov-Gerasimenko. This experiment is based on the resonance of plasma eigenmodes to detect the electron plasma frequency, itself directly related to the electron density. Recent models of mutual impedance probes [1,2] showed that in a two-electron temperature plasma, a double-resonance can be visible on mutual impedance spectra. This characteristic has been observed in-situ within the RPC-MIP data during the post-perihelion operation at all heliocentric distances (from 1.3 to 3.8 AU), corroborated the measurement of a mix of two electron populations done independently by the Langmuir Probes (RPC-LAP) [3,4,5]. For this study, we investigated the RPC-MIP dataset containing the characteristics of a mix of two electron populations in order to characterize the colder population observed by RPC-MIP during the cometary mission. We show that the observation of cold electrons strongly depends on the latitude. Indeed, in the southern hemisphere of 67P, where the neutral outgassing activity was higher than in northern hemisphere during post-perihelion, the cold electrons were more presents which confirms the cooling of the electrons by the cometary neutrals. We also show that the cold electrons are mainly observed outside the electron-neutral collision dominated region (exobase) where electrons are expected to have cooled down which supposed that the cold electrons have been transported. Finally, RPC-MIP measured cold electrons far from the perihelion where the neutral outgassing activity is lower, which suggest that the collisional electron cooling is more efficient than previously expected. [1] Gilet, N., Henri, P., Wattieaux, G., Cilibrasi, M., & Béghin, C., 2017, Radio Science, 52, 1432 [2] Wattieaux, G., Gilet, N., Henri, P., Vallières, X., & Bucciantini, L., submitted in A&A [3] Eriksson, A. I., Engelhardt, I. A., André, M., et al., 2017, A&A, 605, A15 [4] Engelhardt, I. A. D., Eriksson, A. I., Vigren, E., et al., 2018, A&A, 616, A51 [5] Odelstad, E., Eriksson, A. I., Johansson, F. L., et al., 2018, JGR, 123,

Observations of cold electrons by RPC-MIP at 67P/Churuymov-Gerasimenko

International audienceThe Mutual Impedance Probe (MIP) of the Rosetta Plasma Consortium (RPC) onboard the Rosetta orbiter operated during more than two years from August 2014 to September 2016 in order to measure the electron density in the cometary ionosphere of 67P/Churyumov-Gerasimenko. This experiment is based on the resonance of plasma eigenmodes to detect the electron plasma frequency, itself directly related to the electron density. Recent models of mutual impedance probes [1,2] showed that in a two-electron temperature plasma, a double-resonance can be visible on mutual impedance spectra. This characteristic has been observed in-situ within the RPC-MIP data during the post-perihelion operation at all heliocentric distances (from 1.3 to 3.8 AU), corroborated the measurement of a mix of two electron populations done independently by the Langmuir Probes (RPC-LAP) [3,4,5]. For this study, we investigated the RPC-MIP dataset containing the characteristics of a mix of two electron populations in order to characterize the colder population observed by RPC-MIP during the cometary mission. We show that the observation of cold electrons strongly depends on the latitude. Indeed, in the southern hemisphere of 67P, where the neutral outgassing activity was higher than in northern hemisphere during post-perihelion, the cold electrons were more presents which confirms the cooling of the electrons by the cometary neutrals. We also show that the cold electrons are mainly observed outside the electron-neutral collision dominated region (exobase) where electrons are expected to have cooled down which supposed that the cold electrons have been transported. Finally, RPC-MIP measured cold electrons far from the perihelion where the neutral outgassing activity is lower, which suggest that the collisional electron cooling is more efficient than previously expected. [1] Gilet, N., Henri, P., Wattieaux, G., Cilibrasi, M., & Béghin, C., 2017, Radio Science, 52, 1432 [2] Wattieaux, G., Gilet, N., Henri, P., Vallières, X., & Bucciantini, L., submitted in A&A [3] Eriksson, A. I., Engelhardt, I. A., André, M., et al., 2017, A&A, 605, A15 [4] Engelhardt, I. A. D., Eriksson, A. I., Vigren, E., et al., 2018, A&A, 616, A51 [5] Odelstad, E., Eriksson, A. I., Johansson, F. L., et al., 2018, JGR, 123,