To control Covid-19 infection, sodium hypochlorite or bleaching powder is being used to disinfect the human body, along with surface and materials, these days. Sodium hypochlorite is commonly used for water and wastewater treatment, and medical disinfection. The recommended concentration of Sodium hypochlorite for disinfection purpose is 0.45 to 0.50 per cent. Sodium hypochlorite can cause serious health effects, like damaging epithelial tissues, eyes irritation, nausea, and even death if the concentration is high.
There is scientific evidence of severe health hazards of sodium hypochlorite. According to one report published in The New England Journal of Medicine, LD50 of Sodium hypochlorite was found to be 290 mg/kg for an oral dose, and 33.3 mg/kg for an intravenous dose for rats, (LD50 is the dose required to be lethal in 50 per cent of tested animals). This means 290 mg of Sodium hypochlorite (oral dose) is needed to kill 50 per cent of the animal population having 1 kg weight. For example, if a population of 100 people having 65 kg weight, ingests 18.85 g Sodium hypochlorite each, 50 per cent of them will die. Another study published in the Journal of Endodontics found that the intradermal injection of 5.25 per cent sodium hypochlorite causes immediate hemorrhage and edema.
The New England Journal of Medicine study reported the high concentration of sodium hypochlorite could cause significant muscle breakdown that can lead to acute kidney injury. Two other studies reported in The Laryngoscope in 2006 and Veterinary and Human Toxicology state that a large quantity of sodium hypochlorite can result in disastrous complications, including death. It was reported in Critical Care Medicine that the inhalation of sodium hypochlorite vapors can cause damage to the respiratory tract as well as the esophagus.
The disinfection systems/ tunnels which are being used at present use fume or mist of sodium hypochlorite, which can even worsen the effects.
Recently, the World Health Organization (WHO) has also warned against the use of Sodium hypochlorite for human body disinfection. Therefore, it is in the benefit of the common people to stop uncontrolled and unregulated use of Sodium hypochlorite for human body disinfection.
The author is Assistant Professor, National University of Science and Technology, Muscat, Oman