Toxicity and bioaccumulation of Cadmium, Copper and Zinc in a direct comparison at equitoxic concentrations in common carp (Cyprinus carpio) juveniles

Abstract

<jats:title>Abstract</jats:title><jats:p>The individual toxicity and bioaccumulation of cadmium (Cd), copper (Cu) and zinc (Zn) towards common carp juveniles was evaluated in a direct comparison in two experimental setups. First, the fish were exposed for 10 days to different metal concentrations. Accumulated metals were quantified and showed a positive dose dependent uptake for cadmium and copper, but not for zinc. Toxicity was in the order Cd&gt;Cu&gt;Zn with 96h LC<jats:sub>50</jats:sub> values (concentration where 50% of the animals dies within 96h) for Cd at 0.20±0.16 μM, Cu at 0.77±0.03 μM, and Zn at 29.89±9.03 μM respectively, and incipient lethal levels (concentration where 50% of the animals survives indefinitely) at 0.16 μM, 0.77 μM and 28.33 μM respectively. Subsequently, a subacute exposure experiment was conducted, where carp juveniles were exposed to 2 equitoxic concentrations (10% and 50% of LC<jats:sub>50</jats:sub> 96 h) of the three metals. The gill metal content was quantified after 1, 3 and 7 days, and was correlated to electrolyte levels and structural damage of the gill tissue and associated pathological effects. Again a significant dose-dependent increase in gill cadmium and copper, but not in zinc, was observed during the 7-day exposure. Copper clearly affected the sodium levels in the gill tissue, while zinc and cadmium did not significantly alter any of the gill electrolytes. The overall histopathological effects (e.g. hyperemia and hypertrophy) of the metal exposures were mild for most of the alterations, and no metal specific pattern was elucidated for the tested metals except oedema of the primary epithelium which typically occurred in both levels of Zn exposure.</jats:p>

Investigating the effects of a sub-lethal metal mixture of Cu, Zn and Cd on bioaccumulation and ionoregulation in common carp, Cyprinus carpio

“…Although there are several studies describing the adverse effects of waterborne metals, it is 100 difficult to find information on the effects of metal mixtures. We chose a sublethal mixture of 101 Cu, Zn and Cd at a low concentrations (Cu: 0.08 µM; Cd: 0.03 µM and Zn: 3.16 µM) which 102 represent approximately 10% of the 96h LC 50 (the concentration that is lethal to 50% of the 103 population in 96h) earlier determined in our lab under the same exposure conditions (96h LC 50 104 Cu: 0.77 µM; Cd: 0.20 µM and Zn: 30 µM) (Delahaut et al, 2019a). An initial search of the 96h…”

Antagonistic bioaccumulation of waterborne Cu(II) and Cd(II) in common carp (Cyprinus carpio) and effects on ion-homeostasis and defensive mechanisms

“…Moreover, we expect that metal accumulation would trigger defensive mechanisms, such as MT and GR to mitigate possible deleterious effects. Regarding ion-homeostasis, in agreement with previous results from our lab, we expect a Na but not a Ca loss (Castaldo et al 2020, Delahaut et al 2020 2. Material and methods…”

“…Two series of one-week waterborne exposures to binary mixtures of Cd and Cu were performed on common carp (length = 58.5 ± 6.8 mm; weight = 2.3 ± 0.9 g mean ± standard deviation (SD)). Besides control groups, treatments consisted of a fixed concentration of one of the metals at 25 % of the 96h-LC50 previously calculated in our lab (Delahaut et al 2020) combined with 10, 25 and 50 % of the 96h-LC50 of the other metal (indicated as Cufix/Cdvar or Cdfix/Cuvar). Exposure tanks consisting of five (plus one as backup in case of mortality) doublewalled polypropylene (PP) containers per treatment, each filled with 9 l of EPA medium-hard water and containing six fish, were set up in the climate chamber at 20°C.…”

Does zinc oxide nanoparticles potentiate the regenerative effect of platelet-rich fibrin in healing of critical bone defect in rabbits?

“…Nanoparticles had been chosen to be involved in this study from the point of their rapidly growing concepts in tissue engineering for bone regeneration as mentioned by Mirzaei and Darroudi [ 34 ]. ZnONPs were selected because of their low toxicity, low cost and its availability compared to the other different natural non-organic metallic NPs [ 35 ], and Zn 2+ ions are well-known to stimulate bone formation and mineralization and to have an active role in the proliferation of osteoblastic cells [ 36 ]. Although the low toxicity of ZnONPs, their solubility may contribute to cytotoxicity, oxidative stress, and mitochondrial dysfunction [ 37 ].…”