scholarly journals Evaluating the Pollution of the Apies River in Pretoria South Africa

2021 ◽  
Vol 241 ◽  
pp. 01004
Author(s):  
P Tau ◽  
Ro Anyasi ◽  
K Mearns

This study was done to assess the pollution of Apies River using both chemical and microbiological methods. The pollution index of the river revealed that the concentration of most pollutants downstream is more than 50% of the upstream concentration. The natural sources of the pollution in Apies River are the weathering of geological formations; whereas the anthropogenic sources are agriculture; Municipal WWTW and direct deposit of waste into the river. The natural sources of pollution contributed towards chemical pollution; whereas the anthropogenic sources contributed both chemical and microbiological pollution. The Apies River is hypertrophic downstream of the Rooiwal WWTW; however the current physiochemical state of the River warrants its ability to be used for safe irrigation in agricultural practices. The current microbiological state of the River does make it harmful for human consumption especially as drinking water; however, the water should be boiled prior to use to inactivate the bacteria present in the water. The study was able to provide in analysis the variation of the contaminants in the River.

1999 ◽  
Vol 39 (3) ◽  
pp. 1-13 ◽  
Author(s):  
Vladimir Novotny

Until the 1950s most farming was carried out on smaller family farms that used organic fertilizers and essentially their waste production was easily assimilated by soils and receiving water bodies. The period post 1950 has seen a worldwide shift to larger monocultural, intensively operated farm units. The farm yields have increased dramatically, however, to sustain the increasing yields and productivity farms are using large quantities of chemical fertilizers and pesticides. At the same time, deforestation has occurred on a large scale since the 1950s and the deforested land has been converted to agricultural (mostly in developing countries) and urban (both developed and undeveloped countries) land uses. Also, a massive shift of population from rural areas to the cities has occurred in developing countries since the 1950s. Surface and groundwater quality degradation due to agricultural practices and conversion of land to agriculture can be categorized as follows: a) degradation due to land use conversion from native lands to agriculture; b) increased erosion and soil loss due to agricultural practices; c) chemical pollution by fertilizers and pesticides; and d) pollution from animal operations. Abatement of agricultural diffuse sources of pollution can and must be conducted in the context of moving toward sustainable agriculture. Some trends toward sustainable agriculture are already emerging in the US and Europe.


2018 ◽  
Vol 28 (4) ◽  
pp. 1329-1333
Author(s):  
Miodrag Šmelcerović

The protection of the environment and people’s health from negative influences of the pollution of air as a medium of the environment requires constant observing of the air quality in accordance with international standards, the analysis of emission and imission of polluting matters in the air, and their connection with the sources of pollution. Having in mind the series of laws and delegated legislations which define the field of air pollution, it is necessary to closely observe these long-term processes, discovering cause-and-effect relationships between the activities of anthropogenic sources of emission of polluting matters and the level of air degradation. The relevant evaluation of the air quality of a certain area can be conducted if the level of concentration of polluting matters characteristic for the pollution sources of this area is observed in a longer period of time. The data obtained by the observation of the air pollution are the basis for creation of the recovery program of a certain area. Vranje is a town in South Serbia where there is a bigger number of anthropogenic pollution sources that can significantly diminish the air quality. The cause-and-effect relationship of the anthropogenic sources of pollution is conducted related to the analysis of systematized data which are in the relevant data base of the authorized institution The Institute of Public Health Vranje, for the time period between the year of 2012. and 2017. By the analysis of data of imission concentrations of typical polluting matters, the dominant polluting matters were determined on the territory of the town of Vranje, the ones that are the causers of the biggest air pollution and the risk for people’s health. Analysis of the concentration of soot, sulfur dioxide and nitrogen oxides indicates their presence in the air of Vranje town area in concentrations that do not exceed the permitted limit values annually. The greatest pollution is caused by the soot content in the air, especially in the winter period when the highest number of days with the values above the limit was registered. By perceiving the influence of natural and anthropogenic factors, it is clear that the concentration of polluting matters can be decreased only by establishing control over anthropogenic sources of pollution, and thus it can be contributed to the improvement of the air quality of this urban environment.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mariusz Sojka ◽  
Adam Choiński ◽  
Mariusz Ptak ◽  
Marcin Siepak

AbstractThe objective of this study was to analyse spatial variability of the trace elements (TEs) and rare earth elements (REEs) concentration in lake bottom sediments in Bory Tucholskie National Park (BTNP); Poland. The following research questions were posed: which factors have a fundamental impact on the concentration and spatial variability of elements in bottom sediments, which of the elements can be considered as indicators of natural processes and which are related to anthropogenic sources. The research material was sediments samples collected from 19 lakes. The concentrations of 24 TEs and 14 REEs were determined. The analyses were carried out using the inductively coupled plasma mass spectrometry (ICP-QQQ). Cluster analysis and principal component analysis were used to determine the spatial variability of the TEs and REEs concentrations, indicate the elements that are the indicators of natural processes and identify potential anthropogenic sources of pollution. The geochemical background value (GBV) calculations were made using 13 different statistical methods. However, the contamination of bottom sediments was evaluated by means of the index of geo-accumulation, the enrichment factor, the pollution load index, and the metal pollution index. The BTNP area is unique because of its isolation from the inflow of pollutants from anthropogenic sources and a very stable land use structure over the last 200 years. This study shows high variability of TE and REE concentrations in lake sediments. The values of geochemical indices suggest low pollution of lakes bottom sediments. It was found that TEs originated mainly from geogenic sources. However, the concentrations of Li, Ni, Sc, Se, Be, Se, Ag, Re, Tl, Cd, Sb and U may be related to the impact of point sources found mainly in the Ostrowite Lake. Almost all REEs concentrations were strongly correlated and their presence was linked to with geochemical processes. The elements allowing to identify natural processes and anthropogenic pollution sources were Cr, Co, Cu, Ag, Cd, Zn, Bi, Re, Ba, Al and Rb in TEs group and Nd, Gd, Yb, Lu, Eu, Dy and Ce in REEs group. The analysis shows high spatial variability of TE and REE concentrations in lake sediments. The values of geochemical indices point to low pollution of lakes sediments. The anthropogenic sources only for two lakes had an impact on concentrations of selected TEs and REEs. The analyses allowed to identify elements among TEs and REEs documenting geochemical processes and those indicating anthropogenic sources of pollution.


2018 ◽  
Author(s):  
Jean J. Guo ◽  
Arlene M. Fiore ◽  
Lee T. Murray ◽  
Daniel A. Jaffe ◽  
Jordan L. Schnell ◽  
...  

Abstract. U.S. background ozone (O3) includes O3 produced from anthropogenic O3 precursors emitted outside of the U.S.A., from global methane, and from any natural sources. Using a suite of sensitivity simulations in the GEOS-Chem global chemistry-transport model, we estimate the influence from individual background versus U.S. anthropogenic sources on total surface O3 over ten continental U.S. regions from 2004–2012. Evaluation with observations reveals model biases of +0–19 ppb in seasonal mean maximum daily 8-hour average (MDA8) O3, highest in summer over the eastern U.S.A. Simulated high-O3 events cluster too late in the season. We link these model biases to regional O3 production (e.g., U.S. anthropogenic, biogenic volatile organic compounds (BVOC), and soil NOx, emissions), or coincident missing sinks. On the ten highest observed O3 days during summer (O3_top10obs_JJA), U.S. anthropogenic emissions enhance O3 by 5–11 ppb and by less than 2 ppb in the eastern versus western U.S.A. The O3 enhancement from BVOC emissions during summer is 1–7 ppb higher on O3_top10obs_JJA days than on average days, while intercontinental pollution is up to 2 ppb higher on average vs. on O3_top10obs_JJA days. In the model, regional sources of O3 precursor emissions drive interannual variability in the highest observed O3 levels. During the summers of 2004–2012, monthly regional mean U.S. background O3 MDA8 levels vary by 10–20 ppb. Simulated summertime total surface O3 levels on O3_top10obs_JJA days decline by 3 ppb (averaged over all regions) from 2004–2006 to 2010–2012 in both the observations and the model, reflecting rising U.S. background (+2 ppb) and declining U.S. anthropogenic O3 emissions (−6 ppb). The model attributes interannual variability in U.S. background O3 on O3_top10obs days to natural sources, not international pollution transport. We find that a three-year averaging period is not long enough to eliminate interannual variability in background O3.


Author(s):  
Lisa Were ◽  
Gertrude Were ◽  
Kevin Omondi Aduol

Street-vended foods are a major threat to public health because of their microbial contamination. This study investigated hygiene practices and microbial contamination of street foods in Kenyatta University’s environs. Both cross-sectional and experimental designs were adopted. Four (4) major vending stalls at the main entrance to Kenyatta University, gate (A) and at the hind gate at KM shopping center were identified for this study. Twelve (12) food samples were collected from these stalls; sausages, samosas and kachumbari. The foods were collected and transported in cooler boxes to the Microbiology Laboratory at Kenyatta University within 3 hours for analyses. Standard microbiological methods were used for enumeration of Salmonella, coliforms and Escherichia coli. No Salmonella was detected per 25g in all food samples tested. Fifty percent (50%) of kachumbari samples tested positive for E.coli whereas samosas and sausages tested negative. Kachumbari, from all vending stalls, had total coliform levels 4.12 log10 cfu/g, 4.26 log10 cfu/g and 4.21 log10 cfu/g, that did not meet the quality standards (4.00 log10 cfu/g) for ready-to-eat foods. Total coliform counts were below detection limits in samosas and sausages. All (100%) the stalls were exposed to potential contaminants: 75% of the vendors did not wear protective clothing, they handled money and sold food simultaneously, and polythene bags exposed to open air, were used for packaging take away rations. All the foods evaluated were safe for human consumption except kachumbari. Policies on safe street food to be enforced and education and training of vendors on environmental and personal hygiene to be strengthened.


2019 ◽  
Vol 16 (32) ◽  
pp. 833-847
Author(s):  
M. S. MEDEIROS ◽  
A. C. GOULART ◽  
I. S. PACHECO ◽  
F. A. AMARAL ◽  
S. C. CANOBRE

The decrease of the water available for human consumption is directly related to the unregulated and unconscious action from the man himself. In rural areas, this depreciation is related to inappropriate conditions of artesian wells that capture the water (old wells and poorly sealed) and which are usually close to sources of pollution, such as septic tanks and animal grazing. In this context, the objective of the present work was to evaluate the physico-chemical and microbiological quality of underground water samples made available for consumption in three schools in the field next to the municipality of Uberlândia-MG. Methodologically, the data were statistically processed by means of descriptive and multivariate analysis (Pearson correlation coefficient). All schools are supplied by an artesian well, being carried out simplified treatment (chlorination mechanism of chemical treatment). In only one of the schools was identified the presence of a septic tank sewage collection system. Of samples evaluated, all were at odds with the standards laid down in annex XX of the Consolidation Ordinance No. 5 of the Ministry of health (old law 2,914/2011) in at least one of the parameters evaluated. Therefore, the results reflect the possibility of biological contamination of the water by grazing areas located in the region close to the wells, as well as the need for emerging measures, such as regular cleaning and maintenance of storage systems and distribution of the water consumed in the institutions.


2021 ◽  
Author(s):  
Ljubica Šarčevic - Todosijevic ◽  
Snezana Đorđevic ◽  
Vera Popovic ◽  
Ljubisa Živanovic ◽  
Bojana Petrovic ◽  
...  

In addition to physical and chemical pollution of water, from the aspect of the impact of water on the health of the population, monitoring and prevention of microbiological pollution of water, especially water used for drinking, is extremely important. In this paper, the importance of microbiological safety of water in protecting the health of the population is considered.


2020 ◽  
Author(s):  
Kouji Adachi ◽  
Naga Oshima ◽  
Zhaoheng Gong ◽  
Suzane de Sá ◽  
Adam P. Bateman ◽  
...  

Abstract. The Amazon basin is important for understanding the global climate both because of its carbon cycle and as a laboratory for obtaining basic knowledge of the continental background atmosphere. Aerosol particles play an important role in the climate and weather, and knowledge of their compositions and mixing states is necessary to understand their influence on the climate. For this study, we collected aerosol particles from the Amazon basin during the Green Ocean Amazon (GoAmazon2014/5) campaign (February to March 2014) at the T3 site, which locates about 70 km from Manaus, and analyzed using transmission electron microscopy (TEM). TEM has better spatial resolution than other instruments, which enables us to analyse the occurrences of components that attach to or are embedded within other particles. Based on the TEM results of more than 10,000 particles from several transport events, this study shows the occurrences of individual particles including compositions, size distributions, number fractions, and possible sources of materials that mix with other particles. Aerosol particles during the wet season were from both natural sources such as the Amazon forest, Saharan desert, Atlantic Ocean, and African biomass burning and anthropogenic sources such as Manaus and local emissions. These particles mix together at an individual particle scale. The number fractions of mineral dust and sea-salt particles increased almost three-fold when long-range transport (LRT) from the African continent occurred. Nearly 20 % of mineral dust and primary biological aerosol particles attached sea salts on their surfaces. Sulfates were also internally mixed with sea-salt and mineral dust particles. The TEM element mapping images showed that several components with sizes of hundreds of nanometres from different sources commonly occur within individual LRT aerosol particles. We conclude that many aerosol particles from natural sources change their compositions by mixing during transport. The compositions and mixing states of these particles after emission result in changes in their hygroscopic and optical properties and should be considered when assessing their effects on climate.


2019 ◽  
Vol 19 (7) ◽  
pp. 4211-4233 ◽  
Author(s):  
Karl Espen Yttri ◽  
David Simpson ◽  
Robert Bergström ◽  
Gyula Kiss ◽  
Sönke Szidat ◽  
...  

Abstract. Carbonaceous aerosol (total carbon, TCp) was source apportioned at nine European rural background sites, as part of the European Measurement and Evaluation Programme (EMEP) Intensive Measurement Periods in fall 2008 and winter/spring 2009. Five predefined fractions were apportioned based on ambient measurements: elemental and organic carbon, from combustion of biomass (ECbb and OCbb) and from fossil-fuel (ECff and OCff) sources, and remaining non-fossil organic carbon (OCrnf), dominated by natural sources. OCrnf made a larger contribution to TCp than anthropogenic sources (ECbb, OCbb, ECff, and OCff) at four out of nine sites in fall, reflecting the vegetative season, whereas anthropogenic sources dominated at all but one site in winter/spring. Biomass burning (OCbb + ECbb) was the major anthropogenic source at the central European sites in fall, whereas fossil-fuel (OCff + ECff) sources dominated at the southernmost and the two northernmost sites. Residential wood burning emissions explained 30 %–50 % of TCp at most sites in the first week of sampling in fall, showing that this source can be the dominant one, even outside the heating season. In winter/spring, biomass burning was the major anthropogenic source at all but two sites, reflecting increased residential wood burning emissions in the heating season. Fossil-fuel sources dominated EC at all sites in fall, whereas there was a shift towards biomass burning for the southernmost sites in winter/spring. Model calculations based on base-case emissions (mainly officially reported national emissions) strongly underpredicted observational derived levels of OCbb and ECbb outside Scandinavia. Emissions based on a consistent bottom-up inventory for residential wood burning (and including intermediate volatility compounds, IVOCs) improved model results compared to the base-case emissions, but modeled levels were still substantially underestimated compared to observational derived OCbb and ECbb levels at the southernmost sites. Our study shows that natural sources are a major contributor to carbonaceous aerosol in Europe, even in fall and in winter/spring, and that residential wood burning emissions are equally as large as or larger than that of fossil-fuel sources, depending on season and region. The poorly constrained residential wood burning emissions for large parts of Europe show the obvious need to improve emission inventories, with harmonization of emission factors between countries likely being the most important step to improve model calculations for biomass burning emissions, and European PM2.5 concentrations in general.


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