Assessment of Levels, Speciation, and Toxicity of Trace Metal Contaminants in Selected Shallow Groundwater Sources, Surface Runoff, Wastewater, and Surface Water from Designated Streams in Lake Victoria Basin, Uganda

Journal of Environmental and Public Health - Tập 2019 - Trang 1-18 - 2019
G. K. Bakyayita1,2, Ann‐Catrine Norrström2, Robinah Kulabako1
1Department of Civil and Environmental Engineering, Makerere University, Kampala, Uganda
2Department of Sustainable Development, Environmental Science and Engineering, Kungliga Tekniska Högskolan, Brinellvägen, 28 SE-100 44 Stockholm, Sweden

Tóm tắt

The levels, speciation of elements, and toxicity of selected trace metals as well as other parameters in selected surface water, shallow groundwater sources, landfill leachate, and associated surface runoff in the Lake Victoria basin, Uganda, were studied. The WHO guidelines, Ugandan standards, Canadian guidelines and Swedish EPA were used for assessment. The shallow groundwater was acidic with pH values below 6.5. The pH, dissolved organic carbon, flouride, and sulphate levels for all springs were below the guideline values although 52.8% was contaminated with nitrates while 39% was contaminated with chloride ions. Some surface water samples had levels of major elements, such as iron, chromium, aluminium, and manganese, above the guideline values. Speciation studies showed that 74% of the metal ions was bound to dissolved organic matter in surface water, whereas in landfill leachates, the dominant ionic species was metal hydroxides or fulvic acid bound. Risk analysis based on the Swedish EPA showed varied risks of negative effects in 30%–76% of the sample sites ranging from high to increased risk in surface water, whereas the results from modelling sorption data using the Bio-met tool showed potential risk to toxicity effects of Cu2+, Ni2+, Zn2+, and Pb2+ in 15.3%–30.8% surface water samples and 8.3%–62.5% groundwater samples.

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Tài liệu tham khảo

2013, International Journal of Agricultural Research and Reviews, 1, 22

1993, An introduction to global freshwater issues, 3

2000

2006

2003, International Journal of Pure and Applied Bioresource, 2, 35

10.1016/s0269-7491(03)00060-5

2001

10.1007/s100400050015

1999, The annual year book of the water resources management department

10.4314/ajst.v7i1.55197

10.1007/s00254-007-0764-0

10.1016/s0043-1354(03)00235-5

1987, Heavy metal pollution and the need for monitoring: illustrated for developing countries in West Africa, 335

1997

10.1007/bf03326081

10.1007/bf03326153

2002, Lake Victoria and Kampala—history of man and water, Kampala

2001

2013

10.1016/S0160-4120(02)00099-5

2000, Pollution from roads and vehicles and dispersal to the local environment

2012

2013

10.1002/etc.5620201034

2009

2013

2000

2011

1998

1994, Groundwater quality in rural Uganda: hydrochemical considerations for the development of aquifers within the basement complex of Africa, 31

2013, Framework and Guidelines for Water Source Protection

2014, Guidelines for Canadian Drinking Water Quality‐Summary Table Water and Air Quality Bureau

10.1016/j.scitotenv.2007.03.035

10.1007/bf00008445

1999, The national environment regulations (standards for discharge of effluent in water or on land)

2014

10.4314/jasem.v15i2.68512

10.1016/j.scitotenv.2017.05.039