Effects of in Vitro Exposure of Beluga Whale Splenocytes and Thymocytes to Heavy Metals

Abstract

Abstract-The effects of in vitro exposure of beluga whale splenocytes and thymocytes to different concentrations of mercury chloride (HgCl 2 ), cadmium chloride (CdCl 2 ), and lead chloride (PbCl 2 ) were evaluated. The cells were cultured for 66 h with either concanavalin A (Con-A), phytohemagglutinin-P, or without mitogen, after which percentage of cell death and proliferation were evaluated. Increased percentage of cell death was observed in Con-A-stimulated thymocytes cultured with HgCl 2 , while the viability of splenocytes was not affected by exposure to metals. Decreased splenocyte and thymocyte proliferation was observed with the highest concentration of HgCl 2 and CdCl 2 (10 Ϫ5 M), while lower concentrations of these metals (10 Ϫ6 and 10 Ϫ7 M) as well as all the different concentrations of PbCl 2 (10 Ϫ4 , 10 Ϫ5 , and 10 Ϫ6 M) did not significantly influence cell proliferation. Concentrations of metals that were found to affect the proliferation of beluga lymphocytes are similar to those found in the liver of beluga whales from wild populations.

METAL SENSITIVITY OF MARINE MAMMALS: A CASE STUDY OF A GRAY SEAL (HALICHOERUS GRYPUS)

“…Phagocytosis and lymphoblast transformation in gray seal pups are adversely affected in vitro by mercury (Lalancette et al 2003). Effects of heavy metals on beluga whale splenocytes and thymocytes in vitro indicate functional impairment (De Guise et al 1996). A sex‐dependent effect of zinc on phagocytic activity of seal blood leukocytes was found (Pillet et al 2000).…”

Gender Benders at the Beach: Endocrine Disruption in Marine and Estuarine Organisms

“…To date, few studies have directly examined thyroid disruption in marine mammals. PCBs and their hydroxylated metabolites have been identified in tissues [229][230][231][232][233][234][235]237,[248][249][250][251][252], and these compounds specifically alter thyroid homeostasis in other mammals [112,113,246,247]. Thyroid gland abnormalities have been detected in harbor seals from the contaminated North Sea, but a causative link to contaminants has not been established [253].…”

Metal Levels in Southern Right Whales (Eubalaena australis) from Península Valdés, Argentina

“…Specifically, in cetaceans, metal exposure has been correlated with infectious disease mortality, parasitic infections and pneumonias and histopathological changes in lung and kidney tissues [7][8][9]. Cetacean cell culture studies showed that metals can induce cytotoxic, immunotoxic and genotoxic effects [10][11][12][13][14][15][16][17]. Thus, animal and tissue culture studies suggest that metals could be a health concern to cetaceans.…”