Hand Sanitiser Warning

[MickG]

Hi all

I was recently asked to review an SDS for hand sanitiser we were planning to buy in bulk for when office staff return to work.
The compositioin was as follows:

Ethanol, >50%, <100%
Glycerol, >1%, < 2.5%
Methanol, > 1% < 2.5%

After a recent warining in the US and rumours of dodgy sanitisrer, I wanted to check this out further. Just because something toxic is present at sub-CLP classification levels, that does not automatically mean that it is safe to use, particularly when you consider the unusual case of hand sanitisers:
- this is the deliberate application of chemicals to the skin, which are likely to be absorbed into the body;
- they are being used every day by people in industry, professional users and the general public;
- the use has gone on for months, and is likely to go on for months more.

The guidance for people making hand sanitisers from the HSE is here https://www.hse.gov.uk/coronavirus/asse ... avirus.pdf .

It does say "In making commercial decisions, manufacturers need to be mindful of maintaining high levels of safety and efficacy of the products they make available to the public and others" and "If you are supplying biocidal hand sanitiser products you must comply with general product safety regulations" .

However, there is no specific guidance on impurities such as methanol in hand sanitisers that I can find in the UK.

My next thought was that as this is for business use, we should carry out a COSHH assessment. The HSE provide a lot of information on this via COSHH essentials, but this does not appear to cover the deliberate application of chemicals to the skin.

So, I then looked at the DNELs, the Derived No Effect Levels which are held in the REACH registration dossier for Methanol: https://echa.europa.eu/registration-dos ... /15569/7/1. There is also a European Occupational Exposure limit for methanol, which you can find below the Infocard for Methanol here: https://echa.europa.eu/substance-inform ... 00.000.599 .

The summary EU figures are:
- Long term OEL (8 hour exposure), 260 mg/m3/ 200 ppm methanol
- systemic worker DNEL 20 mg/kg bodyweight / day
- general population DNEL 4 mg/kg bodyweight / day

There are more detailed DNELs in the dossier, but methanol appears to be the type of substance where the route of exposure is relatively unimportant. (Presumably this is a reflection of short chain alcohols being absorbed through the skin, as they will dissolve fats).

I then did a "quick and dirty" calculation on the amount of methanol which a worker might be exposed to, which I could then compare to the DNEL....

assuming a 5ml or 5g squirt 20 times a day (not unreasonable at the moment)...

5g x 20 x 0.025 = 2.5g of methanol on the skin each day.

or 2.5g / 70 kg (me) = 36mg / kg bodyweight / day

against a DNEL of 20 mg /kg bodyweight / day

or a general population DNEL of 4 mg/kg bodyweight / day

So the percentage of methanol looked to be too high. Nearly doublke for workers and 10 times for the general population. I figure that it probably best to use the general population DNEL as there may be sensitive people on site, or some of it may end up at people's homes!

There's not much guidance out there for the UK or EU, but the US FDA have issued guidelines called "Policy for Temporary Compounding of Certain Alcohol-Based Hand Sanitizer Products During the Public Health Emergency Immediately in Effect Guidance for Industry" https://www.fda.gov/media/136118/download ("compounding" is the term used in the USA for "formulating" or making mixtures).

This gives a limit on the amount of methanol which is acceptable as being no more than 630 ppm (Table 1, page 12 of the document).


Not surprisingly, I have not approved the purchase, and have let the supplier know the reasons why, so they can adjust their formulation if they want to!

I've also let the HSE know (without disclosing supplier info), so that they can do something to prevent people being harmed through long term exposure to methanol.


If anyone needs any help assessing sanitisers, please let me know.

Of course, there are non-alcohol sanitisers which containg biocidal products. These are subject BPR and the manufcaturer needs to hold a full licence or derogation. I have heard of bocides present in hand sanitisers which are not approved for skin contact, so caution is needed here too.


I hope this information is useful for you, and will keep you posted on developments around hand sanitiser formulations in the UK.

Thanks
Mick

[Alexis]

Many thanks for this Mick.

I am sure it will be useful for many.

[Andyblue]

Hi Mick,
Nice analysis of the product. Having decided to update the HSE it may have been no bad idea to actually say who the provider is, its not as if the supplier is doing anything wrong. It saves the HSE making generalised comments that may not be relevant to the wider suppliers/users.

[bernicarey]

Wow Mick, you've made my head hurt just reading your numbers.

So according to the SDS,

Ethanol, >50%, <100%
Glycerol, >1%, < 2.5%
Methanol, > 1% < 2.5%

The ethanol could be anything between 50% and 100%.

That's terrible.

I'm about to start writing an SDS for a new client who is going online to manufacture sanitizer to the WHO formulation #1 (WHO #2 uses Isopropyl Alcohol instead of the Ethanol).
The Final concentrations of active ingredients are :
Ethanol, 80%
Glycerol, 1.45%
Hydrogen Peroxide 0.125 %

I wouldn't touch something where they effectively say it could be 99.999% Ethanol.

To be an effective anti Bacterial, it has to be at 70-80%, because it uses the water molecules to do it's work (apparently but I'm no chemist).

WHO Formulation guide:
https://apps.who.int/iris/bitstream/han ... g.pdf?ua=1

[MickG]

Wow Mick, you've made my head hurt just reading your numbers.

So according to the SDS,

Ethanol, >50%, <100%
Glycerol, >1%, < 2.5%
Methanol, > 1% < 2.5%

The ethanol could be anything between 50% and 100%.

That's terrible.

Sorry if I've blown your mind! it shows that chemical safety around a simple household item is far from simple!

Those kind of ranges are actually pretty standard with some SDS software.... I have seen 30 - 100 % before!
Its probably a case of putting the numbers in the software without properly thinking about them!