Bio-Indicator Analysis of Pollution Due To Electronic Waste Recycling Activities: The Heavy Metal Concentrations in Earthworms, Feathers and Eggs of Birds Collected Around Agbogbloshie

Abstract

Introduction: Informal sector recycling of e-waste could lead to release of various toxic substances; including the oxides of heavy metals into the ambient environment and therefore contributes significantly to environmental pollution. Objectives: The aim of the study was to analyze heavy metals concentration levels in bird feathers and eggs and earthworm found at the Agbogbloshie e-waste dumpsite. Methods: A cross sectional study was conducted at the Agbogbloshie e-waste site near Accra. Cattle egret quill feathers and eggs as well as earthworms were collected around the e-waste site and analyzed for heavy metals concentrations (As, Cd and Pb) using an Atomic Absorption Spectrophotometry. Data was entered into STATA 15 and analyzed. Medians, inter quartile range and correlation analysis were done to establish relationship of between heavy metals levels in feathers, eggs and earthworms. Results: median As concentration was [6.672 (IQR: 5.78-7.18)] μg/g in feathers; [6.203 (IQR: 0.26-9.50)] μg/g in eggshell; [6.229 (IQR: 4.53-7.14)] μg/g in egg content and [18.46 (IQR: 8.24-24.33)] μg/g in earthworm, followed by Pb [1.886 (IQR: 1.44-2.25)] μg/g in feathers; [1.1741 (IQR: 1.11-1.99)] μg/g in eggshell; [1.181 (IQR: 0.86-1.47)] μg/g in egg content and Pb [5.39 (IQR: 4.71-9.99)] μg/g in earthworm, while Cd was the least with median level [0.024 (IQR: 0.01-0.05)] μg/g in feathers; [0.142 (IQR: 0.00-0.41)] μg/g in eggshell; [(0.000 (IQR: 0.00-0.00)] μg/g in egg content and [5.102 (IQR: 4.98-5.99)] μg/g in earthworm. A rank spearman correlation showed strong positive correlations for heavy metals concentration between BF and EGC, EGS and EGC and EGS and BF with [r = 0.8558; n = 90; p˂0.05]; [r = 0.8572; n = 90; p˂0.05] and [r = 0.8487; n = 90; p˂0.05] respectively. Conclusion: Pollution levels of bird feathers, eggshell, egg content and earthworm are reflective of the extent of environmental pollution within the Agbogbloshie ecosystem.