Evaluation of Pollution Load: Heavy Metal Contents and Physiochemical Properties of the Great Kwa River, Calabar, Cross River State, Nigeria

Abstract

Background and Objectives: Human activities can increase the amount of pollutants in the environment leading to water pollution. The contamination of surface water and sediments by heavy metals can result in adverse health conditions of humans, due to the bioaccumulation of metals. This study seeks to assess the pollution load of some heavy metals and physiochemical properties in Great Kwa River.
 Methods: Water samples were collected once a month from three stations within four selected months in wet and dry seasons. Samples were preserved by adding 10 ml of 6 N Nitric acid and stored at 5oC. Laboratory investigations were conducted and data analyzed statistically.
 Findings: The mean pH, dissolved O2, biological O2 demand, conductivity, NO3, NH4 and temperature were 7.44±1.24, 5.58±0.92, 0.957±0.002, 32.84±2.941, 0.1030±0.1701, 0.113±0.018 and 28.2±1.48, respectively during wet season. Mean concentration of Cu, Fe, Cr, Mn, Zn, Ni are 0.225±0.003, 0.489±0.009, 0.068±0.016, 0.102±0.006, 0.794±0.003, 0.031±0.001, respectively during the wet season. Mean concentration of metals in the river during the wet season were ranked in descending order as Zn > Fe > Cu > Mn > Cr > Ni. Iron (0.489±0.009 mg/l and 0.438±0.003 mg/l), chromium (0.068±0.016 mg/l and 0.055±0.008 mg/l), nickel (0.031±0.001 mg/l and 0.025±0.002 mg/l) were higher than Nigerian standard for drinking water in both seasons. The contamination factor of heavy metals in station 3 were 2.14, 1.56, 1.09, 0.89 for Fe, Cr, Ni, Zn, respectively, indicating moderate contamination. The pollution load index in stations 1, 2, 3 were 0.262, 0.537, 0.981, respectively.
 Conclusion: The present study provided base-line information on the pollution levels and physiochemical properties of the river. The river was not highly polluted by heavy metals except iron, chromium and nickel that were found above the recommended standards. However, drinking of water from the river over one’s lifetime is not advisable due to detrimental health hazards.

Green remediation and enhanced metal accumulation using moringa oleifera leaf extracts and hydrocarbon-degrading microorganisms in crude oil-impacted soils of the niger delta, nigeria

“…Contamination is correlated with the degree of industrialization and intensity of chemical usage. Controlled and uncontrolled disposal of waste, accidental and process oil spillage, mining and smelting of metalliferous ores, sewage sludge application to agricultural soils are responsible for the migration of contaminants into non-contaminated sites as dust or leachate and contribute towards contamination of our ecosystem (Ekpo et al, 2021). Concern over soil contamination by crude oil or hydrocarbon products in general, is gathering momentum after a similar feeling has been around for a while on oil spills, which enjoy more media coverage because of the often-spectacular visual effects images conveyed to people.…”

“…The impacts of urbanization or industrialization continuously limit or stress their natural cleansing potential. This in turn has led to the decline in the quality of air, soil and water in areas where industrial development activities are prevalent (Ekpo et al, 2021). A wide variety of chemicals have been detected in soil, water, and air (Ekpo et al, 2021).…”

“…This in turn has led to the decline in the quality of air, soil and water in areas where industrial development activities are prevalent (Ekpo et al, 2021). A wide variety of chemicals have been detected in soil, water, and air (Ekpo et al, 2021). Heavy metals pose a critical concern to human health and the environment due to their common occurrence as contaminants, low solubility in biota, and the classification of several heavy metals as carcinogenic and mutagenic (Ekpo et al, 2021).…”

“…A wide variety of chemicals have been detected in soil, water, and air (Ekpo et al, 2021). Heavy metals pose a critical concern to human health and the environment due to their common occurrence as contaminants, low solubility in biota, and the classification of several heavy metals as carcinogenic and mutagenic (Ekpo et al, 2021). Bioremediation processes may be directed towards accomplishing; Complete oxidation of organic contaminants (termed mineralization),Biotransformation of organic chemicals into smaller less toxic metabolites, or Reduction of highly electrophonic halo-and nitrogroups by transferring electrons from an electron donor (typically a sugar or fatty acid) to the contaminant, resulting in a less toxic compound.…”

An Assessment of the Effect of Pollution on Zooplanktons in Calabar Great Kwa River, Nigeria

“…It has earlier been reported that high human activities around a station in the Calabar Great Kwa River and the release of wastes was responsible for the poor species richness in the area [5]. Ekpo et al [6,7] reported the distribution and seasonal variation of Zooplanktons in the Calabar Great Kwa River, also suggested that the river could be under pollution stress and also recommended that laws are enforced to control the disposal of effluent and other waste products. Base-line information on the pollution levels and physiochemical properties of the river has also been reported [8].…”