Zinc toxicity

About: Zinc toxicity is a research topic. Over the lifetime, 727 publications have been published within this topic receiving 34583 citations. The topic is also known as: zinc poisoning.

Silicon distribution in leaves and roots of rice and maize in response to cadmium and zinc toxicity and the associated histological variations.

Abstract: At present, the levels of cadmium (Cd) and zinc (Zn) in arable land are high and affect the growth and development of important food crops, including rice and maize. However, the application of silicon (Si) in contaminated areas increases the metal tolerance potential of these plants. This work aimed to study the variations in the distribution pattern of endogenous Si in various tissue regions in roots and leaves of rice and maize exposed to cadmium (Cd) and zinc (Zn) stresses. For these experiments, 45 day-old rice (var. Varsha) and maize (var. CoHM6) seedlings were treated with 1.95 g Zn and 0.45 g Cd kg-1 soil. Under Cd stress, the distribution of Si was high in the cortical region of the root, but under Zn stress, the highest Si deposition was found in the endodermis. In leaves, Si deposition was high in both the mesodermis and stelar regions of Cd-treated plants but more Si was deposited in the mesodermis tissue of Zn-treated plants. Heavy metal (Cd and Zn) accumulation and Si deposition showed a strong negative correlation in the roots of rice and maize plants. Complexation with metal ions and redistribution of Si were considered the major mechanisms in Si-mediated mitigation of Cd and Zn stress. Cd- and Zn-induced anatomical changes, such as endodermal thickening, deposits in the xylary elements and aerenchyma formation in the roots of rice and maize, were also associated with the Si distribution.

Chapter 9 Physico-Chemical Processes Affecting Copper, Tin and Zinc Toxicity to Algae: A Review

Abstract: Publisher Summary This chapter focuses on the physic-chemical processes affecting copper, zinc, and tin toxicity to algae. Both Cu and Zn are essential algal micronutrients, cofactors in numerous biochemical processes. The availability of a nutrient or toxic substance can be significantly affected by precipitation. Methods for modeling the effects of adsorption–desorption reactions have been previously reviewed. Useful predictions of algal response require an understanding of the relative importance of these interactions (both magnitude and time dependence). Photoreduction and dissolution of Mn oxides by dissolved humic substances has been proposed as an important factor regulating dissolved Mn distribution in seawater. Photodegradation of iron (Fe) chelates also enhances Fe uptake by algae. Anderson et al. observed that Fe uptake by Thalassiosira weissflogii in a chemically defined medium dominated by FeEDTA complexation doubled in the presence of light.

Evaluation of cytotoxic effect of zinc on raji cell-line by mtt assay

Abstract: Background: Zinc has significant effects on structural and functional activities of many proteins and enzymes involved in biological activities, especially the regulation of immunesystem. Symptoms of zinc toxicity include nausea/vomiting, fever, cough, diarrhea, fatigue, neuropathy, and dehydration. Further signs include growth retardation, altered iron function, anemia, copper deficiency, decreased immune function, decreased HDL (high density lipoprotein), increased LDL (low density lipoprotein), and increased HgbA1C.This study was carried out to examine the invitro effects of different concentrations of zinc on viability and death of T-lymphoid (Raji) cell line. Methods: In this study, the cell line was exposed to different concentrations of zinc (10nanoM to 500microM) followed by incubation (37° C, 5% CO2) at various time points (12 to 72 h). The cells were, then, evaluated using trypan blue exclusion dye, MTT assay (mitochondorial thiazol tetrazolium), and light microscopy. Results: The results of this study showed almost different responses to different amounts of zinc in the T cell line (Raji). Zinc concentrations below 100μM at different incubation time points had little or no effects on the cell line compared to the controls. Higher concentrations of zinc viability (>100μM) diminished to 70% at 12 hour and less than 50% at 24 to 72 hours of incubation. Conclusion: It can be concluded that zinc has a dose-dependent cytotoxicity effect on Raji cells.