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- Wilkinson, John L., et al.
(författare)
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Pharmaceutical pollution of the world's rivers
- 2022
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 119:8
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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| 2. |
- Arshadi, S., et al.
(författare)
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Pure and carbon-doped boron phosphide (6,0) zigzag nanotube: A computational NMR study
- 2015
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Ingår i: Physica B-Condensed Matter. - : Elsevier BV. - 0921-4526. ; 477, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- Calculations were performed for investigation of the properties of the electronic structure of Carbon-Doped Boron Phosphide Nanotube (CDBPNT). Pristine and three models of C-doped structures of (6,0) zigzag BPNT were studied at density functional theory (DFT) in combination with 6-311G* basis set using Gaussian package of program. The calculated parameters reveal that various B-11 and P-31 nuclei are divided into some layers with equivalent electrostatic properties. The electronic structure properties are highly influence(' by replacement of B-11 and P-31 atoms by C-12 atoms in pristine model. Furthermore, the HOMO-LUMO gap energy for suggested doped models (l), (II) and (Ill) were lower than pure BPNT pristine systems. The dipole moment values of models (H) and (Ill) were decreased to 1.788 and 1.789, respectively while the dipole moments of model (l) were enhanced to 4.373, in compare to pure pristine one (2.586). The magnitude of changes in Chemical Shielding (CS) tensor parameters revealed that the electron density at the site of P-31 was higher than that at the sift of B-11 due to carbon doping. (C) 2015 Elsevier B.V. All rights reserved.
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