Medical Malacology Department, Theodor Bilharz Research Institute, Imbaba, Giza, Egypt.
Biological and Geological Sciences Department, Faculty of Education, Ain Shams University, Roxy, Heliopolis, Cairo, P.C.11757, Egypt.
Environ Sci Pollut Res Int. 2023 Oct;30(48):105967-105976. doi: 10.1007/s11356-023-29786-x. Epub 2023 Sep 18.
Metal pollution has many dangerous environmental and human health consequences due to the bioaccumulation in the tissues. The present study aims to measure the bioaccumulation factor of the manganese (Mn) heavy metal in Biomphalaria alexandrina snails' tissues and water samples. The current results showed the concentration of Mn heavy metal in water (87.5 mg/l) and its bioaccumulation factor in Helisoma duryi tissue was higher than that in tissues of Physa acuta and B. alexandrina snails. Results showed that 87.5 mg/l Mn concentration had miracidicidal and cercaricidal activities. Also, this concentration decreased the mean total number of the hemocytes after exposure for 24 h or 48 h, while increasing both the mean mortality and phagocytic indices of the hemocytes of exposed snails. It caused alterations in the cytomorphology of the hemocytes of exposed snails after 24 or 48 h, where the granulocytes had irregular cell membranes and formed pseudopodia. Besides, levels of testosterone (T) and estradiol (E) were increased after exposure to 87.5 mg/l Mn metal compared to the control group. Also, it increased MDA (malonaldehyde) and TAC (total antioxidant capacity) contents, while decreasing SOD (superoxide dismutase). Besides, it caused significant histopathological damages in both hermaphrodite and digestive glands, represented in the degeneration of the gonadal, digestive, secretory cells, and the connective tissues. Therefore, B. alexandrina might be used as a sensitive bioindicator of pollution with Mn heavy metal to avoid ethics rules; besides, they are readily available and large in number.
由于金属在组织中的生物积累，金属污染对环境和人类健康有许多危险的影响。本研究旨在测量生物组织中锰（Mn）重金属的生物积累系数。目前的结果表明，水中 Mn 重金属的浓度（87.5mg/L）及其在福寿螺组织中的生物积累因子高于在扁卷螺和埃及伊蚊组织中的浓度。结果表明，87.5mg/L 的 Mn 浓度具有杀蚴和杀尾蚴的活性。此外，该浓度降低了暴露 24 小时或 48 小时后秀丽隐杆线虫总血细胞数的平均值，同时增加了暴露线虫的血细胞死亡率和吞噬指数。它导致暴露线虫的血细胞细胞形态发生改变，24 小时或 48 小时后，粒细胞的细胞膜不规则，形成伪足。此外，与对照组相比，暴露于 87.5mg/L Mn 金属后，睾丸激素（T）和雌二醇（E）的水平升高。此外，它增加了丙二醛（MDA）和总抗氧化能力（TAC）的含量，同时降低了超氧化物歧化酶（SOD）的含量。此外，它导致雌雄同体和消化腺都出现明显的组织病理学损伤，表现为性腺、消化、分泌细胞和结缔组织的退化。因此，扁卷螺可能被用作 Mn 重金属污染的敏感生物指示剂，以避免伦理规则；此外，它们很容易获得且数量众多。
