Guidelines for hand hygiene in healthcare settings

Groundwater geochemistry, quality, and pollution of the largest lake basin in the Middle East: Comparison of PMF and PCA-MLR receptor models and application of the source-oriented HHRA approach.

Groundwater geochemistry, quality, and pollution of the largest lake basin in the Middle East: Comparison of PMF and PCA-MLR receptor models and application of the source-oriented HHRA approach

Due to the spreading of the coronavirus (COVID-19) in Iran, restrictions and lockdown were announced to control the infection. In order to determine the effects of the lockdown period on the status of the water quality and pollution, the concentrations of Al, As, Ba, Cr, Cu, Mo, Ni, Pb, Se, and Zn, together with Na+, Mg2+, Ca2+ and electrical conductivity (EC), were measured in the Zarjoub River, north of Iran, in both pre-lockdown and post-lockdown periods. The results indicated that water pollution and associated human health risk reduced by an average of 30% and 39%, respectively, during the lockdown period. In addition, the multi-purpose water quality index also improved by an average of 34%. However, the water salinity and alkalinity increased during the lockdown period due to the increase of municipal wastewater and the use of disinfectants. The major sources of pollution were identified as weathering, municipal wastewater, industrial and agricultural effluents, solid waste, and vehicular pollution. PCA-MLR receptor model showed that the contribution of mixed sources of weathering and municipal wastewater in water pollution increased from 23 to 50% during the lockdown period. However, the contribution of mixed sources of industrial effluents and solid wastes reduced from 64 to 45%. Likewise, the contribution of traffic-related sources exhibited a reduction from 13% in the pre-lockdown period to 5% together with agricultural effluent in the post-lockdown period. Overall, although the lockdown period resulted in positive impacts on diminishing the level of water pollution caused by industrial and vehicular contaminants, the increase of municipal waste and wastewater is a negative consequence of the lockdown period. 

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COVID-19 and urban rivers: Effects of lockdown period on surface water pollution and quality- A case study of the Zarjoub River, north of Iran

Pollution of river bottom sediments with heavy metals (HMs) has emerged as a main environmental issue related to intensive anthropopressure on the water environment. In this context, the risk of harmful effects of the HMs presence in the bottom sediments of the Warta River, the third longest river in Poland, has been assessed. The concentrations of Cr, Ni, Cu, Zn, Cd, and Pb in the river bottom sediments collected at 24 sample collection stations along the whole river length have been measured and analyzed. Moreover, in the GIS environment, a method predicting variation of HMs concentrations along the whole river length, not at particular sites, has been proposed. Analysis of the Warta River bottom sediment pollution with heavy metals in terms of the indices: the Geoaccumulation Index (Igeo), Enrichment Factor (EF), Pollution Load Index (PLI), and Metal Pollution Index (MPI), has proved that, in 2016, the pollution was heavier than in 2017. Assessment of the potential toxic effects of HMs accumulated in bottom sediments, made on the basis of Threshold Effect Concentration (TEC), Midpoint Effect Concentration (MEC), and Probable Effect Concentration (PEC) values, and the Toxic Risk Index (TRI), has shown that the ecological hazard in 2017 was much lower. Cluster analysis revealed two main groups of sample collection stations at which bottom sediments showed similar chemical properties. Changes in classification of particular sample collection stations into the two groups analyzed over a period of two subsequent years indicated that the main impact on the concentrations of HMs could have their point sources in urbanized areas and river fluvial process.

https://www.mdpi.com/2075-163X/11/3/327/pdf

Analysis of Spatial Variability of River Bottom Sediment Pollution with Heavy Metals and Assessment of Potential Ecological Hazard for the Warta River, Poland

Water pollution by heavy metals is one of the leading environmental concerns as a result of intense anthropogenic pressure on the aquatic environment. This constitutes a significant limitation to the human right of access to drinking water. In this context, the risk to humans from exposure to heavy metals and arsenic in water from rivers subject to mining influence in the Central Andes of Peru was assessed. Water samples were collected from seven rivers at 63 sampling sites, and concentrations of Cu, Fe, Pb, Zn, and As were determined using flame atomic absorption spectrophotometry. Cluster analysis was used to group 21 sampling sites into four groups with similar chemical characteristics, and principal component analysis was used to simplify the complex relationship between the toxic elements by generating two main components with a total percentage of variation of 86%. Fe, Zn, and As had higher percentages of contribution in the Mantaro, Cunas, and Chia rivers. The hazard quotient was highest for children and adults. The hazard index for ingestion of all the studied heavy metals and As was higher than the threshold value (HIing > 1). HIing in 43% of the rivers indicated that the adult population is at risk of non-carcinogenic effects, and HIing in 14% of the rivers revealed a very high health risk. The risk of cancer by ingestion for children varied from medium to high risk and for adults from low to high risk.

/pdf/human-risk-from-exposure-to-heavy-metals-and-arsenic-in-10d6v9mxje.pdf

Human Risk from Exposure to Heavy Metals and Arsenic in Water from Rivers with Mining Influence in the Central Andes of Peru

The concentration of Cu, Fe, Pb, Zn and As in the surface water intended for human consumption and other uses in the Mantaro River basin were analysed using multivariate methods. The water samples were collected from seven water bodies in the Junín region in June 2019, in the low discharge period. In each body of water, a sector with six sampling sites was established. The Cu, Fe, Pb, Zn and As contents were determined by the flame atomic absorption spectrophotometry method. The correlation analysis revealed positive and significant correlations (P < 0.05) for the Zn/Pb, Pb/Fe and Zn/Fe pairs with a good association, higher than 0.80 and for the Pb/Cu, Fe/Cu, As/Pb and As/Zn pairs a weak degree of association (P < 0.05). The analysis of the main components showed three components with their own values > 1. The hierarchical grouping analysis classified the evaluated water bodies into three groups according to the concentration of the Cu, Fe, Pb, Zn and As. The high concentrations of heavy metals and arsenic recorded in the CIMIRM and MERIS irrigation channels reveal that the Mantaro River continues to be a sink for mine wastewater discharges and runoff from mining liabilities at the headwaters of the Mantaro basin. It is, therefore, necessary to implement urgent management policies to control and reduce the levels of contamination by potentially toxic metals and metalloids in the Mantaro River.

Potentially toxic metals and metalloids in surface water intended for human consumption and other uses in the Mantaro River watershed, Peru

Human risk associated with the ingestion of artichokes grown in soils irrigated with water contaminated by potentially toxic elements, Junin, Peru.

Data on the detection of essential and toxic metals in soil and corn and barley grains by atomic absorption spectrophotometry and their effect on human health

Introduccion: En la superficie cutanea residen microorganismos responsables del balance bioquimico, algunas son patogenas y persisten a pesar del lavado de manos. Objetivo: Identificar la flora bacteriana resistente al lavado de manos en estudiantes universitarios. Metodos : Se realizo el estudio observacional analitico de tipo longitudinal, para esto se enrolaron a estudiantes universitarios que recibieron previamente charlas educativas sobre higiene de manos, posteriormente se tomaron muestras antes y despues del lavado de las manos. Resultados: De 80 muestras analizadas se identifico a Staphylococcus epidermidis como el mas frecuente en 95 % de los estudiantes y con el lavado de manos se redujo a 60 %; el segundo agente fue Staphylococcus saprophyticcus, que estuvo presente en 75 % de los casos y despues del lavado, en 35 %; E. coli ocupo el tercer lugar, se encontro en 42,5 % de las muestras y tras la higiene de manos se redujo a 17,5 %. Para los agentes transitorios como Klebsiella (p < 0,05 ) y Pseudomonas, el lavado de manos fue mas efectivo; sin embargo, E. coli fue la enterobacteria que permanecio elevada a pesar de la higiene de manos ( p = 0,01). Conclusion: Algunas colonias de E. coli son resistentes al lavado de manos, similar a los agentes residentes como Staphylococcus epidermidis, Staphylococcus saprophyticcus y Staphylococcus aureus .

/pdf/flora-bacteriana-resistente-al-lavado-de-manos-en-dgf866jcoa.pdf

Salomé Ochoa

Papers

Human Risk from Exposure to Heavy Metals and Arsenic in Water from Rivers with Mining Influence in the Central Andes of Peru

Potentially toxic metals and metalloids in surface water intended for human consumption and other uses in the Mantaro River watershed, Peru

Human risk associated with the ingestion of artichokes grown in soils irrigated with water contaminated by potentially toxic elements, Junin, Peru.

Data on the detection of essential and toxic metals in soil and corn and barley grains by atomic absorption spectrophotometry and their effect on human health

Flora bacteriana resistente al lavado de manos en estudiantes universitarios