Variations in reference values utilized for the evaluation of complex pollution indices of potentially toxic elements: A critical review

Environmental Challenges

Glory Richard¹  Ayobami Omozemoje Aigberua²  Omamoke Ekakitie³  Sylvester Chibueze Izah⁴ 

[1] Corresponding author.;Department of Community Medicine, Faculty of Clinical Sciences, Niger Delta University, Wilberforce Island, Bayelsa State, Nigeria;Department of Environment, Research and Development, Anal Concept Limited, Elelenwo, Rivers State, Nigeria;Department of Microbiology, Faculty of Science, Bayelsa Medical University, Yenagoa, Bayelsa State, Nigeria;

关键词: Different background values;    Environmental contaminants;    Trace metal micro-pollutants;    Geometric mean;    Median mean;   

DOI  :  

来源: DOAJ

【 摘 要 】

The study provides a critical evaluation of different background values commonly utilized in assessing the complex pollution indices (CPI) of potentially toxic elements in environmental components. Contamination indices offer helpful information about the health and quality status of various ecological systems. In this study, twelve CPI were studied, with eight indirectly requiring background values for computation (sum of pollution index, pollution load index, average pollution index, vector modulus of pollution index, background enrichment factor, potential ecological risk index, degree of contamination, nemerow pollution index), while the other four which do not require background values for computation (contamination security index, multi-element contamination degree, exposure factor, probability of toxicity), were used to assess the ecological effects of copper, zinc, manganese, lead, chromium and nickel in soil. Analysis of the indices that required reference values for computation showed significant variations in mean values, except for median mean (MM) and geometric mean (GM) consideration that showed no significant differences. The values of GM and MM showed high statistical similarity using Ward's hierarchical cluster analysis (HCA) and Pearson Correlation as compared to other background values. Furthermore, the reliability analysis revealed that combined background values provide a better tool for assessing environmental components, with a Cronbach's Alpha of 0.811. Another effective approach for risk assessment was observed with calculations involving the use of control values, showing a Cronbach's Alpha of 0.747. Of all the background values evaluated, the reliability index depicted the potential ecological risk index as the most crucial for assessing ecological risk, with a Cronbach's Alpha range of 0.881 – 0.905 when an item is deleted. Therefore, we recommend the utilization of control values as background concentration, whilst potential ecological risk index should be strongly considered for the environmental risk assessment of trace metal micro-pollutants.

【 授权许可】

Unknown