Cleaning products for your house!  It's baffling to know what is best to use.  We all know about eco friendly products, but nothing can touch the power and effectiveness of bleach for cleaning the toilet and getting rid of all those nasty germs.  Or can it?

Bleach is, well, just bleach isn't it?  We explain bleach as you've probably never heard it.  Once you have read the blog you will then have a better understanding of bleach and you can decide if you want to continue using it in the future.

So, just how good at cleaning is bleach, really?

We’ve done our research and can tell you that bleach is a terrible cleaning product.  That may surprise you, but read on and you’ll understand why.

Bleaching is a process that’s been used for thousands of years to whiten clothing.  Products used for bleaching are predominantly chlorine-based, including sodium hypochlorite - which is the chemical name for what we colloquially refer to as household bleach.

Household bleach is great at removing stains from fabric and disinfecting surfaces or tools.  Why? Because of the chlorine, of course.  The bleach is really good at oxidising certain organic material.

Stains tend to be made up of a mixture of organic molecules, and the components that absorb certain wavelengths of light are called chromophores (the wavelength that isn’t absorbed is the colour that we recognise).  Bleach oxidises the chromophore, disrupting its ability to absorb light.

Oxidising bleaches work very generally, and repeated use of bleach on clothing will speed up the breakdown of the material, whether that be carbohydrate-based clothing such as cotton, or protein-based clothing like wool via the same method.

Household bleach permanently denatures the proteins in microorganisms which leads to cell death and prevents pathogenicity.  Specifically, interactions with heat shock proteins and, in some cases, lipids within the cell walls of bacteria.

All of this seems great, doesn’t it?  Removes stains and kills microbes, pathogenic and benign alike.  However bleach alone doesn’t actually contain any cleaning agents.

Cleaning agents

Cleaning agents are liquids that lift dirt from a substrate.  Cleaning agents can be natural or synthetic, but work in similar ways.

Cleaning agents commonly contain surfactants, chelating agents and builders, and solvents.  Additionally, many contain preservatives to minimise bacterial degradation.

Dirt can either be organic material, inorganic material, or a combination of the two.

Organic material consists of food, blood, grease, mould, or petroleum oils, and these are usually removed with more alkaline (a higher pH) cleaners. Inorganic material includes rust, clay, and scale - acidic cleaners are used for these.  A combination of the two is the hardest to remove and may need a very specific, highly built cleaning agent.

Surfactants (surface acting agents) work by reducing the surface tension between a liquid and a solid, in this case the detergent and the dirt.  They are amphiphilic which means they have both a hydrophobic tail (repels water but attracts grease) and a hydrophilic head (attracts water but repels grease) at either end of the molecule.

The hydrophobic tails of the surfactant binds to the dirt on the substrate, surrounding it.  Then water binds to the hydrophilic heads and pulls the dirt away from the substrate and into the solution.

The hardness of water, i.e. how many metal ions are present in water, affects the performance of the cleaning agent.  The hardness of water is dependent upon the concentration of calcium, magnesium, iron and manganese ions, which bind to surfactants unintentionally.  Each unintentional binding removes surfactant from the solution and ultimately means less dirt can be removed.

Chelating agents are added to the cleaning agent to mop up as many metal ions (by attaching to them and altering their ionic charge from positive to negative) as possible to allow the surfactants to continue with their intended purpose.  A commonly used natural chelating agent is citric acid and a synthetic example is ethylene diamine tetra acetate (EDTA).  Builders work in a similar way to chelating agents, they either sequester the metal ions or precipitate them by forming compounds too large to be dissolved by water.

Lastly, preservatives are added to prolong the shelf-life of the cleaning agent, whether that be natural chemical decay or bacterial degradation.  Soaps made from animal fats tend to succumb to the effects of bacteria, in which case butylated hydroxdytoluene and stannic chloride are added to the solution.  Synthetic detergents have methyl paraben and propyl paraben included, if detergents weren’t biodegradable they would accumulate in the water system (which is what happened with the original phosphate chelating agents).

In summary, bleach is great at changing the colour of material by destroying the chromophore, and at killing microorganisms.  It isn’t very good at lifting dirt from a substrate.  For this, a cleaning agent is necessary which typically comprises a surfactant, chelating agent, and preservative in solution with water.

Thanks for reading this blog post, we're Clean Cleaner, an exceptional domestic cleaning service based in Edinburgh.  If you've enjoyed reading this, please give it a like or share it with your friends so that we know we're doing something right!  We've got some other articles that we're sure you'll be interested in - for example, how to clean silver and how to clean stainless steel. Until the next time, friends.