Cadmium

Cadmium is considered to be a non-essential and highly toxic element to a wide variety of living organisms, including man, and it is one of the widespread pollutants with a long biological half-life (Plunket 1987; Klaassen 2001; Rahman et al. 2004). A provisional, maximum, tolerable daily intake of cadmium from all sources is l-1.2g/kg body mass (Bortoleto et al. 2004) and is recommended by FAO-WHO jointly. This metal enters the environment mainly from industrial processes and phosphate fertilizers and is transferred to animals and humans through the food chain (Wagner 1993; Taylor 1997; Sattar et al. 2004). Cadmium is very hazardous because humans retain it strongly (Friberg et al., 1974), particularly in the liver (half-life of 5 to 10 years) and kidney (half-life of 10 to 40 years). The symptoms of cadmium toxicity produced by enzymatic inhibition include hypertension, respiratory disorders, damage of kidney and liver, osteoporosis, formation of kidney stones, and others (Vivoli et al. 1983; Dinesh et al. 2002; Davis 2006). Environmental, occupational, or dietary exposure to Cd(II) may lead to renal toxicity, pancreatic cancer (Schwartz 2002), or enhanced tumor growth (Schwartz et al. 2000). The safety level of cadmium in drinking water in many countries is O.Olppm, but many surface waters show higher cadmium levels. Cadmium can kill fish in one day at a concentration of 10 ppm in water, whereas it can kill fish in 10 days at a concentration of 2 ppm. Studies with cadmium have shown harmful effects on some fish at concentrations of 0.2ppm (Landes et al. 2004). Plants can accumulate cadmium up to a level as high as 5 to 30 mg/kg, whereas the normal range is 0.005 to 0.02 mg/kg (Cameron 1992). Taken up in excess by plants, Cd directly or indirectly inhibits physiological processes, such as respiration, photosynthesis, cell elongation, plant-water relationships, nitrogen metabolism, and mineral nutrition, all of which result in poor growth and low biomass. It was also reported that cadmium is more toxic than lead in plants (Pahlsson 1989; Sanita'di Toppi and Gabbrielli 1999).

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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