Palmiet River water exceeded the permissible limits for Cr, Ni and Pb, especially in the industrial area. All metals were greater than the ERM in the Palmiet River, while only Ni exceeded this limit in the Sezela River.
Introduction
- Problem Statement
- Aim
- Specific Objectives of the Study
- References
34; Physico-Chemical Parameters for Current Water Quality Testing of Khan River in Indore, India." International Journal of Environmental Science Research. 34; A Comparative Analysis of Physico-Chemical Properties and Heavy Metal Pollution in Major Rivers across India.” International Journal of Science and Research 3(8).
Study Area
Palmiet River
An industrial waste water pipe from the Pinetown industrial area leading into the river was visible and the sediment in this area was orange in colour. The river bed was mostly covered with gravel and this flow was from the Pinetown industrial district.
Sezela River
The river then flows through the rural area of Uswani where residents use the water for domestic purposes. The river flows under the N2 highway at the Sezela dam where residents use the water for domestic and recreational purposes.
Theory
Pollutants
Inorganic Pollutants
Heavy Metals
- Chromium
- Copper
- Lead
- Nickel
- Zinc
In humans, Ni is an important micronutrient that functions as a metalloenzyme and aids in the adsorption of Fe in the blood (Avenant-Oldewage and Marx 2000). It is a highly mobile metal in acidic soils and under alkaline conditions it is found in the hydroxide form as a precipitate (Botes 2003).
Water Quality
- Water Quality Parameters
- Water Quality Guidelines
- Sediment
- Sediment Quality Guidelines
Changes including pH, temperature, redox potential and ion exchange affect the fate of metals in sediment (Filgueiras et al. 2002). Reduction of Fe(III) and Mn(IV) under anoxic conditions releases adsorbed trace metals (Filgueiras et al. 2002).
Quality Assurance
Statistical Analysis
Analytical Techniques
- Microwave Assisted Digestion
- Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES)
- Ion Chromatography
Ionization perturbations are due to plasma temperature, element ionization potential, and element concentration (Botes 2003). Spectral overlaps are one of the main problems of ICP-OES and are directly related to high temperatures.
Comparative Studies
The Umgeni River is a large river in KwaZulu-Natal that has been documented for high contaminant levels over the years. The Palmiet River has been known for metal and anion contamination since 1985 (De Villiers and Malan 1985).
34;Advances in Inductively Coupled Plasma-Optical Emission Spectrometry for Environmental Analysis." Instrumentation Science and Technology. 34;Removal of Chromium from Groundwater Using Neem Leaves as Adsorbent." International Journal of Environmental Research. 34;Heavy Metal Pollution in Surface Water and Sediment: A Preliminary Assessment of an Urban River in a Developing Country." Ecological Indicators.
34;Occurrence of Adverse Biological Effects in the Range of Chemical Concentrations in Marine and Estuarine Sediments." 34;Heavy Metals in Water and Sediment: A Case Study of the Tembi River." Journal of Environmental and Public Health 2014: 5. 34;Sediment pollution due to toxic heavy metals in the Mithi River in Mumbai.” Advances in Analytical Chemistry.
34;A comparative analysis of physicochemical properties and heavy metal pollution in three major rivers across India." International Journal of Science and Research 3(8). 34;Mode-coupled plasma optical emission spectrometry First-Axis Inductive Configuration: A Review of Applications." Journal of the Brazilian Chemical Society. 34; Certified Reference Materials for Inorganic and Organic Contaminants in Environmental Matrices.” Analytical and Bioanalytical Chemistry.
Methodology
- Sampling
- River sediment sampling
- River water sampling
- Sample Preparation
- River sediment
- River water
- Certified Reference Material
- Acid digestion: Sediment
- Sediment sequential extraction procedure
- Analysis
- ICP-OES
- Ion Chromatography
- Statisitical Analysis
- References
The remaining filtered water was stored with a few drops of concentrated HNO3 (Analytical Grade, Merck) until ICP-OES analysis. The fermentation vessels were then sealed and placed on a microwave rotor (following the procedure described in the user manual). After complete digestion, the samples were then filtered into a 25 ml volumetric fluid and brought to the mark using double distilled water.
The residue was washed with 20 ml of distilled water, shaken for 20 minutes on an orbital shaker and centrifuged for 20 minutes. The residue from step 1 was added to 20 mL of hydroxylammonium chloride solution, sealed, and set aside on an orbital shaker for 16 hours. 25 mL of ammonium acetate solution was added to the residue in the vial, closed and placed aside on an orbital shaker for 16 hours.
The Perkin Elmer Optima DV5300 ICP-OES was calibrated with standards prepared from commercial 1000 mg L-1 solutions (Sigma-Aldrich). A Metrohm 762 Compact Ion Chromatograhy (Leonberg, Germany) with a Metrosep A Supp 5 150 x 40 mm column was used to quantify the nitrate, sulfate, and phosphate ions in the filtered water samples. The certification of the extractable content (mass fractions) of Cd, Cr, Cu, Pb and Zn in freshwater sediment following a sequential extraction procedure BCR-701.
Results and Discussion
Quality Assurance
The calculated experimental values had a recovery percentage greater than 85%, indicating that the sequential extraction method was valid.
Seasonal Rainfall
Palmiet River
- Physical Parameters
- Metal Concentration in Water
- Anion Concentration in Water
- Total Metal Concentration in Surface Sediment
- Chromium and Copper
- Nickel
- Lead
- Zinc
- Bioavailable Metal Concentration in Surface Sediment
- Chromium
- Copper
- Nickel
- Lead
- Zinc
- Statistical Analysis of the Palmiet River
- Synopsis
Only nitrates and sulphates were found in the water of the Palmiet River at locations 1, 6 and 8 (Figure 5.1). At the source, Cr and Cu concentrations are increased in summer and this may be due to anthropogenic input from a textile industry in the area. Again, the increased Pb concentration at the source in summer is attributed to the textile industry in the vicinity of the source (Manzoor et al. 2006).
The correlation between the water and sediment concentrations is further evidence of anthropogenic influence on the river, especially with elevated levels in the spring and fall in the industrial area. The zinc concentrations before the industrial area are generally low. However, the increased zinc concentration at the source in summer is attributed to the textile industry in the area. Although the distribution is similar to that in the other seasons, most of the Cr is in the residual fraction.
As with other metals, the distribution of BCR metals is markedly different in the industrial area (sites 3–5). This is alarming, as the ERM value in the first fraction is exceeded ten times. The graph of results for Ni in the Palmiet River (Figure 5.9) is similar to the other metals studied.
Sezela River
- Physical Parameters
- Metal Concentration in Water
- Anion Concentration in Water
- Total Metal Concentration in Surface Sediment
- Chromium and Copper
- Nickel
- Lead
- Zinc
- Bioavailable Metal Concentration in Surface Sediment
- Chromium
- Copper
- Nickel
- Lead
- Zinc
- Statistical Analysis of the Palmiet River
- Synopsis
Phosphates, sulfates and nitrates were analyzed in the Sezela River for summer and winter (Figure 5.10). This may be due to anthropogenic input from the sugar mill industry in the area. Lead released by fossil fuel combustion accumulates in the environment over time (Callender and Rice 2000, Nomngongo and Ngila 2014).
The distribution of Cr in the bioavailable fraction (fractions 1, 2, and 3) decreases downstream with downstream sites having a distribution similar to the source. Thus the distribution, although similar to other seasons, has the majority of Cr in the residual fraction. Copper in the remaining fraction is predominant in most seasons, however there are places where the distribution is different.
The score plot for Cr distribution in the Sezela River (Figure 5.16) is similar to other heavy metals studied. The dot plot provides further evidence of the site associations with metal distribution in the Sezela River. The bioavailable metal distribution illustrates that metals are mainly in the residual fraction, therefore not available for uptake.
Comparison of the Palmiet and Sezela Rivers
- Anion Pollutants
- Metal Pollutants
- Comparison of Palmiet and Sezela Rivers to other South African Rivers
- Anions
- Metal Contaminants
The Palmiet River had higher average concentrations of metals in the sediment than the Sezela River (Table 5.8). The Palmiet River has metal, metal processing, paint and chemical manufacturing industries in the Pinetown area, which contribute significantly to metal concentrations in the river. In comparison, metal concentrations in the Sezela River are significantly different from Palmiet (ANOVA, p >0.05) and are significantly lower.
The Sezela River flows through sugarcane plantations, similar to the Umdloti River (Olaniran et al. 2013). Rivers with similar anthropogenic activities in South Africa were compared with the Palmiet and Sezela rivers (Table 5.10). The Palmiet River, a tributary of the river, has higher sediment concentrations than larger rivers, which is a concern.
The Sezela River has higher average metal concentrations in sediment than similar agricultural rivers (Table 5.10). Metal accumulation in the sediment may be due to the use of fertilizers and additives in the sugarcane fields. The agricultural activity around the Sezela River is a larger scale activity compared to the Tyume and Mvudi regions which rationalizes the higher concentrations as more fertilizers and resources are utilized.
34; Assessment of Trace Metal Pollution of Surface Water and Sediment: A Case Study of the Mvudi River, South Africa.". 34;Analysis of Some Heavy Metals in River Water, Sediment and Fish from the Ganges River at Allahabad." Environmental Monitoring and Assessment. 34; Geological and anthropogenic influences on the inorganic water chemistry of the Jukskei River, Gauteng, South Africa.” South African Journal of Geology.
34;Fraction distribution and risk assessment of heavy metals in sediments collected from the Yellow River, China.". 34;Multivariate analysis of trace metals in textile effluents in relation to soil and groundwater." Journal of Hazardous Materials. 34; Heavy metal pollution of the Palmiet River: KwaZulu-Natal South Africa." International Journal of Scientific Research in Environmental Sciences.
34;Assessment of physicochemical qualities and heavy metal concentrations of Umgeni and Umdloti rivers in Durban, South Africa." 34;Determination of lead, chromium and zinc in sediments of an urbanized river in Mauritius." Environment International. 34;Zinc speciation in sediments of a polluted river, as an estimate of its bioaccessibility." Environmental Monitoring and Evaluation.
Conclusion
The system would require a harsh event to mobilize the metals from the residual fraction, which is highly unlikely. Agricultural activities may not introduce a metal pollution load to the system over a short period of time, but have the potential to accumulate pollutants and introduce toxicity problems over a period of time. A recommendation for the Palmiet and Sezela Rivers would be the implementation of regular monitoring of nutrient and metal concentrations with the addition of stricter protocols in place.
Nutrient analysis would be important, especially in agricultural systems, as nutrient influx increases the effects of algal blooms. Analysis of agricultural rivers for nutrients, which would provide data on water quality and appropriateness of use. It would also provide information on fertilizers and the ability of the crop to absorb nutrients.
Analysis of sediment cores in industrial rivers to determine the period of pollutant deposition. Analyzes of water and sediment for pesticides to determine if organic pollution is a problem in rivers. A comparative study of the effect of anthropogenic activity on the Palmiet and Sezela rivers, South.
