A multi-tissue biomonitoring investigation of toxic trace elements and their trophic transfer potential in a semi aquatic bird species, the Cattle Egret (Bubulcus ibis). (August 2022)

• Record Type: Journal Article
• Authors: Zaman, Muhammad Hamza; Mustafa, Ghulam; Sheikh, Muteeb Ahmad; Qadir, Abdul; Shahid, Syed Umair; Abbasi, Naeem Akhtar
• Is Part Of: Chemosphere. Volume 300(2022)
• Publication Date: 2022-08
• Subjects: Bioaccumulation -- Tissues -- Birds -- Health effects -- Toxicity; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2022.134582
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: The constant exposure of toxic trace elements can elicit adverse health effects particularly in birds and species residing higher at the food web. The current study is designed to evaluate the tendency of toxic trace elements viz. Cd, Cr, Pb, Cu, As and Hg to bioaccumulate in liver, kidney, blood, pelvic and pectoral muscles of cattle egret ( Bubulcus ibis ) collected from premises of a metropolitan city, Lahore, Pakistan. Further, the Trophic Transfer Potential of these elements was also estimated using prey/food samples of cattle egret . All of the selected toxic trace elements except Hg and As were detected with varying concentrations in different tissues of cattle egret. In general, toxic trace elements followed the pattern as Cu > Pb > Cd > Cr in tissues of cattle egret. The maximum mean (Min-max) concentrations (μg/g) of Cu 0.58 (0.11–0.93) and Pb 0.46 (0.40–0.54) in blood and Cd at 0.46 (0.40–0.54) were observed in liver. Similarly, the highest mean (min-max) concentration (μg/g) of Cr 0.17 (0.09–0.25) was recorded in pectoral muscle. In general, blood and liver were found as the most contaminated tissues followed by kidney, pectoral and pelvic muscles. Differences of trace elements were found non-significant (all P > 0.05) among tissues of cattle egret reflecting their homogenous distribution in body. Principal Component Analysis (PCA) corroborated lack of strong association between any of the trace elements and tissues. All the toxic trace elements except Cr showed higher tendency of trophic transfer potential through food chain in all the tissues of Cattle Egret (TTF >1). Although the current study revealed decreasing trends of toxic trace elements, yet their still presence in the local environment and greater likelihood of trophic transfer can undoubtedly cause some severe health effects to the already declining bird populations. Graphical abstract: Image 1 Highlights: Toxic trace elements were examined in multiple tissues of Cattle Egret and its food. In general, Cu was highest in tissues of cattle egret followed by Pb, Cd and Cr. Hg and As were below detection limit in all samples of Cattle Egret and its food. Blood and liver reflect highest contamination of toxic trace elements. All metals except Cr showed higher likelihood of trophic transfer.