Cadmium Toxicity- a Health Hazard and a Serious Environmental Problem -an Overview

Cd 2+ a heavy metal accumulates in the body and has a very long biological half-life (10–30 years) in humans. Environmental cadmium contamination occurs through industries related to batteries, coatings, electroplating, alloys, plastics, glasses, ceramics, enamels and artists’ colors, zinc, copper, lead, and iron ores treatment, coal and oil burning power plants, weathering of parent rocks etc. This review is mainly focused on general characteristics of cadmium, effect on human health in relation to different organs such as kidneys, liver, lungs, reproductive system etc. and mechanism of toxicity. Renal toxicity, hepatotoxicity and carcinogenicity are the major effects of cadmium induced toxicity. Production of reactive oxygen species, free radical induced cell damage, interference with calcium and vitamin-D metabolism (major mechanism involved in cadmium induced bone damage), oxidative DNA damage, glutathione depletion, accumulation as metallothionein complex (Renal toxicity), CFTR (Cystic fibrosis transmembrane conductance regulator) dysfunction (lung toxicity), chromosomal aberrations, modification of transcription factors, altering the antioxidant defense system are the observed mechanisms involved in cadmium induced cytotoxicity. Exogenous supplementation of glutathione (GSH) and metallothionein (MT) will play protective roles against cadmium toxicity. Reducing the use of cadmium in industries or avoiding of Cadmium exposure and recycling the cadmium products prevent the cadmium induced cytotoxicity to some extent.