I am sure you have heard before that your toilet seat is cleaner than your kitchen bench. Is it true, or just an old wives tale?
I am sure there is lot of variability from house to house, but here are some of the studies that I imagine most of the facts originally came from:
An investigation of microbial contamination in the home.
A study of the microbial content of the domestic kitchen.
Reduction of faecal coliform, coliform and heterotrophic plate count bacteria in the household kitchen and bathroom by disinfection with hypochlorite cleaners.
I will review the most recent study:
They looked at 14 sites (sink faucet handle, refrigerator handle, bench, floor next to kitchen sink, cutting board surface, bathroom sink drain area, bathroom sink faucet handles, toilet flush handle, top and underside of toilet, floor around base of toilet, bath drain area, and bathroom counter top) in 15 houses (with at least one child under 12 years) over three different interventions: #1 No intervention (control), #2: Given cleaning product, #3: Given product with specific instructions.
Some of the interesting results:
The sites with the highest densities of faecal coliforms during the control period were the sponge/dishcloth, the kitchen sink drain area, the bath sink drain area and the kitchen faucet handles.
Amazing! The toilet seat does not even feature in the top four, and three of the top four sites are in the kitchen.
The sites with the lowest concentration of faecal coliforms during the control period were the refrigerator handle, the bathroom counter top, the bathroom floor around the toilet and the toilet seat.
So in terms of faecal bacteria, the area around the toilet is a lot cleaner than the kitchen sink. Reflect for a minute as to your reaction if you dropped some food in the kitchen sink vs the floor around the toilet….
It was of interest that the toilet seat was found to have the least bacteria contamination in all cases for all categories of bacteria in this study.
So the toilet seat would be a better place to eat your lunch off than the kitchen bench – or in fact any of the other 13 places tested!
But then some of this data is put in context:
Potential health benefits resulting from the use of disinfectant cleaners in the home is difficult to determine as relatively little information is available on the subject. The proportion of household outbreaks of gastroenteritis that arise from surface cross-contamination as opposed to inadequately cooked or stored food is also unknown.
They go on..
However, there is evidence that the survival and transfer of potentially pathogenic bacteria via environmental surfaces is important.
And in conclusion:
The most contaminated sites within the home are those which tend to remain moist, such as the sponge/dishcloth and drain areas, and the site that is most frequently touched, the kitchen faucet handles.
So I guess the lesson is to keep things dry, and clean more the areas that are touched most often?
On cleaning:
Ordinary cleaning practices may do little to reduce the microbial load. The introduction of hypochlorite cleaning products into the home results in a significant reduction of bacteria in most cases.
Hypochlorite (I am told by Wikipedia) can be found in bleach.
Will you ever look at touching the kitchen faucet the same again?
