Acute and subacute toxicity evaluation of calcium carbide and ethylene glycol in Wistar albino rats

CaC2-induced ripening: Unveiling the bitter truth behind sweet fruit

Fruit ripening is a natural, irreversible process crucial for developing luscious flavor and appealing appearance. Fruits are lauded for their health benefits, forming a key part of a balanced diet. Regrettably, the continued use of calcium carbide (CaC2) to ripen fruit persists in various regions due to its low cost and perceived effectiveness. This method raises significant concerns about health, safety, and the resultant fruit quality and flavor. CaC2 and CaC2-ripened fruits contain harmful substances like inorganic arsenic and phosphorus hydrides, posing considerable health risks including chronic toxicity upon consumption or exposure to acetylene released during CaC2 application. Ensuring food safety requires adherence to regulatory standards governing harmful substances in food. Thus, understanding the risks of consuming CaC2-ripened fruit is crucial for crafting strategies to protect consumers' nutritional well-being and food safety. This review presents a comprehensive analysis of the impacts and apprehensions regarding use of CaC2 as a ripening agent in fresh fruit.

Chronic exposure of industrial grade calcium carbide and ethylene glycol exert genotoxic effect in Wistar albino rats

OBJECTIVES

Calcium carbide (CaC2) and ethylene glycol (EG) are the two commonly used fruit ripening agents. The toxic effects of these chemicals on internal organs were reported in experimental animals. Even though the adverse effects of these compounds have been investigated for many years, there are no sufficient data available with regard to genotoxic effects. The present study evaluates the genotoxic effect of chronic exposures of CaC2 and EG in Wistar albino rats.

METHODS

CaC2 and EG were administered to the rats orally for 180 days. Chromosomal aberrations and micronuclei formation were analysed in bone marrow and peripheral blood cells. Comet assay was performed to analyse the DNA strand break. The toxic effects of the chemicals were analysed by MTT assay with normal human intestinal epithelial (IEC-6) cells.

RESULTS

Upon chronic exposure, CaC2 and EG caused chromosomal aberrations, micronuclei formation and  DNA strand breaks extensively in bone marrow and peripheral blood cells. In MTT assay, the chemicals were found to be toxic to IEC-6 cells with IC50 values at 160 and 200 μg/mL for CaC2 and EG, respectively.

CONCLUSIONS

The results show that these chemicals have a potential to cause genomic level of toxicity which may lead to carcinogenic event at a chronic level exposure. The study warns to reinforce the administrative measures against the use of CaC2 and EG for fruit ripening process.

Calcium carbide-induced derangement of hematopoiesis and organ toxicity ameliorated by cyanocobalamin in a mouse model

Background

Calcium carbide (CaC₂) is a chemical primarily used in the production of acetylene gas. The misuse of CaC₂ to induce fruit ripening is a global challenge with a potential adverse effects to human health. Additionally, CaC₂ is known to contain some reasonable amount of arsenic and phosphorous compounds that are toxic and pose a danger to human health when ingested. The current study sought to characterize CaC₂ toxicity and elucidate any protective effects by cyanocobalamin (vitamin B₁₂), a well-established antioxidant and anti-inflammatory bio-molecule. Female Swiss white mice were randomly assigned into three groups; the first group was the control, while the second group was administered with CaC₂. The third group received CaC₂ followed by administration of vitamin B12. The mice were sacrificed at 60 days post treatment, hematological, biochemical, glutathione assay, cytokine ELISA and standard histopathology was performed.

Results

CaC₂ administration did not significantly alter the mice body weight. CaC₂ administration resulted in a significant decrease in packed cell volume (PCV), hemoglobin (Hb), red blood cells (RBCs) and RBC indices; indicative of CaC₂-driven normochromic microcytic anaemia. Further analysis showed CaC₂-driven leukopenia. Evidently, vitamin B₁₂ blocked CaC₂-driven suppression of PCV, Hb, RBCs and WBCs. Monocytes and neutrophils were significantly up-regulated by CaC₂. CaC₂-induced elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and bilirubin signaled significant liver damage. Notably, vitamin B₁₂ stabilized AST, ALT and bilirubin in the presence of CaC_2, an indication of a protective effect. Histopathological analysis depicted that vitamin B₁₂ ameliorated CaC₂-driven liver and kidney injury. CaC₂ resulted in the depletion of glutathione (GSH) levels in the liver; while in the brain, kidney and lungs, the GSH levels were elevated. CaC₂ administration resulted in elevation of pro-inflammatory cytokines TNF-α and IFN-γ. Vitamin B₁₂ assuaged the CaC₂-induced elevation of these pro-inflammatory cytokines.

Conclusions

These findings demonstrate for the first time that oral supplementation with vitamin B₁₂ can protect mice against CaC₂-mediated toxicity, inflammation and oxidative stress. The findings provide vital tools for forensic and diagnostic indicators for harmful CaC₂ exposure; while providing useful insights into how vitamin B₁₂ can be explored further as an adjunct therapy for CaC₂ toxicity.