People around the globe are now terrified of Covid-19, and searching relentlessly for protective & preventive measures against this virus. Staying at home, washing hands frequently, cleaning yourself and surrounding with available sanitizer or disinfectant – are some of the precautions, whereas protective measures are yet to be developed. Nevertheless, early precautions are definitely helpful (there is a saying of Prophet Mohammad sallallahu alaihi wa sallam about tieing up camel then putting trust in our creator Allah Azzawazal to protect the camel, perfectly resembles taking precautions and seeking repentance from Almighty, to keep yourself away from such a deadly virus). But definitely, mixing bleach with hand sanitizer to use as a combined disinfectant won’t increase your chance to survive, rather this mixture can put you in real vulnerable situation…
At first, let’s get familiarised with some of the disinfectants , which are most effective against this pandemic:
For Surface Disinfection:
a) Bleaches are preffered at microbiological laboratories as a disinfectant. Household Chlorine-based Liquid Bleach is mainly a solution of 3 to 6% sodium hypochlorite NaOCl with rest of the water. It is widely used to disinfect toilet or kitchen surfaces (having a shelf life of 6 to 9 monthes), and commonly available in local shops.
(b) Bleaching Powder is a complex mixture consisting calcium hypochlorite Ca(ClO)2, dibasic calcium hypochlorite, Ca3(ClO)2(OH)4 and dibasic calcium chloride, Ca3Cl2(OH)4 . You can guess the main active ingredient of bleaching powder among these three : yes, calcium hypochlorite it is.
To Sanitize Hands:
(c) Rubbing Alcohol (surgical spirit) is 70% denatured ethyl alcohol or 70% isopropyl alcohol – check the label of bottle to know which alcohol does it contain. As isopropyl alcohol is harmful to consume and available at a large scale because of it’s industrial uses , it is being used widely in rubbing alcohol. If denat ethanol is used, some foul elements (methanol, pyridine, benzene, DEP, bittrex etc.) are added to make it undrinkable.
(d) Almost same goes for Alcohol-based Hand Sanitizers. Most of the time you will find isopropyl alcohol (IPA) with more than 75% strength as active ingredient in sanitizers. Sanitizers also contain about 1.5% glycerin to keep your hands moisturized, tiny amount of H2O2 ( 0.125% in final product ) to reduce spores, about 20% water to increase contact time between skin & alcohol content, and some fragrance to mask unpleasant smell of isopropanol. Yes, ethanol (80% in final product) is used sometimes but IPA-based hand sanitizers are more popular. There are also some “Hand sanitizer Gels” in market which I personally don’t like to work with, as WHO recommended use of liquid hand sanitizers against Covid-19 virus with no mention about gel hand sanitizers.
(e) Dettol is also a great disinfectant if it is used in right proportions. Along with Chloroxylenol 4.8% (w/v) as active ingredient, Dettol Antiseptic liquid has 5-10% Isopropyl alcohol in it’s formula (you can check this info from Safety Data Sheet of Dettol Antiseptic posted on their website).
It’s time to give the final blow: what will happen if I mix bleach or bleaching powder with IPA ? As both are disinfectants, may be their effectiveness will rise if I mix them in a bottle & then spray? May be one of them will show synergistic effect on other?
No, nothing will happen like that. Rather, if handled carelessly, it can cost your life. Chlorine-based disinfectant produces active chlorine, which oxidizes elements of cell wall or cell membrane of the germs and kills the bacteria / virus / spores. But this chlorine can also oxidize isopropyl alcohol of rubbing alcohol/hand sanitizer/Dettol to acetone, and acetone will undergo Halo-form reaction to make one of the deadliest compound: CHLOROFORM !!
Reactions are given below considering bleaching powder and isopropyl alcohol as reactants (quite same type of reaction will happen with Bleach) :
(1) Bleaching Powder Reacts with water to form:
Ca(ClO)2 + H2O → Ca(OH)2 + HOCl + HCl
HOCl + HCl → H2O + Cl2
(2) Iso Propyl Alcohol gets Oxidised by Chlorine & become acetone:
CH3-CHOH-CH3 + Cl2 → CH3-CHOCl-CH3 + HCl
CH3-CHOCl-CH3 → CH3-CO-CH3 + Cl− + H+
(3) Acetone converts into Chloroform by reacting with remaining HOCl. Its a exothermic reaction, so it will evolve much heat during the reaction.
CH3-CO- CH3 + 3 HOCl → CHCl3 + CH3COOH + H2O
(with bleach, overall reaction will be:
3 NaClO + (CH3)2CO → CHCl3 + 2 NaOH + CH3COONa )
Chloroform is considered Carcinogenic by ACGIH, EPA , and the International Agency for Research on Cancer. According to CDC, chloroform affects the central nervous system (brain), liver, and kidneys after a person breathes air or drinks liquids that contain large amounts of chloroform.
The anesthetic use of chloroform has been discontinued because it caused deaths due to respiratory failure and cardiac arrhythmia. Chloroform can cause depression of the central nervous system (CNS), ultimately producing deep coma and respiratory center depression. Also, chloroform converts slowly in air to phosgene (COCl2), releasing HCl in the process ; the hepatotoxicity and nephrotoxicity of chloroform is thought to be due largely to phosgene (“Chloroform”. Encyclopedia of Toxicology. Elsevier. pp. 561–565).
So, probably by this time you have known how to stop someone if you see him discussing about mixing Bleach & Sanitizer or Dettol !