Colleagues, I have been asked by a client to review the CoSHH arrangements for the storage / use / controls etc of an additive called diacetyl used in ther food flavouring business.

From the Safety Data Sheet, it looks pretty nasty stuff without any obvious substitute and the CoSHH controls - temperature, enclosure. extraction, automation, RPE, sampling, health surveillance etc etc look very onerous in relation to the relatively small amounts used.

Whilst onerous, the CoSHH aspects are manageable, we have tried to look into the possibilities of "contracting out" the process to another much more  / better equipped for this process. Whilst I am familiar with contractor control - roofers, engineers etc I couldn't find anthing on contracting out a process on HSE's website.

Could anybody give some pointers as to where I could find this, particularly what contractor safety assessment we would have to do on them?

My thanks in advance,

Tom

Edited by user 04 October 2024 12:08:13(UTC)  | Reason: missing words

Can I suggest your client engages someone with a bit more chemical knowledge given "Diacetyl" returns 132 possible substances on the ECHA database a CAS# or EC No. helps narrow down the search.

There are many preservatives that as 100% product are horrendous for human helath and the environment which in use are in such trace amounts the worst scenario is the illicitation of an irritation raction in some, not all, exposed persons.

You may actually be creating unecessary concerns and work.

As a chemist, my first question is diacetyl what?

Just as others have suggested, I suspect that wishing to outsource this may be an over-reaction.  I have occasionally wanted to see processes outsourced but these have tended to involve nasties that have to be sprayed in the absence of any suitable enclosure to spray them in.

What exactly would need to be outsourced - is it the mixing of a product to a formula?  There certainly are companies that do this kind of contract manufacturing.  They might even be your client's competitors or work for them as it's quite common for the same manufacturing site to make similar products under their own brand and also for other brands.

If you do outsource, then there will have to be a sales process in which the contract manufacturer's ability to fulfil the client's requirements in terms of cost, quality and delivery are demonstrated and tested and this will include questions about protecting the client's property, about food hygiene, and about operating the process in compliance with health, safety, environmental and other regulations and standards, among many other considerations.  This stuff will also be in the contract terms.  It's a much, much bigger process than asking about their health and safety and you should probably not expect to be the person leading it. 

Nine times out of ten, contract manufacturers will have long ago got fed up with these types of questions and audits and will try to head most of them off by having certification to ISO 9001, ISO 14001, ISO 45001 and often various other certifications to give assurance that their systems work and are legally compliant, allowing the sales process to concentrate on the specifics of what the client needs.

Outsourcing is not eliminating - it is transferring to another and as such does not deserve to be considered as the top of the hierarchy of controls.

The “diacetyl” we seem to be talking about here seems to be  butanedione or butane-2,3-dione, which has a CAS number 431-03-8. There is no WEL in for it in EH40.  If you look at the SDS there are a number of hazard statements including high flammability, toxicity if inhaled, skin irritation,  and others. It is safe to use as a food additive as it is added in tiny quantities in the order of a few milligrams per litre.  You must be looking at its bulk handling and the question is how much you are handling and what do you do with it. Only then can you decide if the possible controls you mentioned are ”onerous”.  Organizations can and do handle  such materials perfectly safely if they carry out the proper risk assessment and apply suitable controls. I am not sure why you seem to have dismissed possible controls so decisively.    If this is a food related business they must be used to much more elaborate controls.  

https://www.hse.gov.uk/safetybulletins/diacetyl-vapour-exposure.htm#:~:text=Diacetyl%20vapour%20can%20be%20generated,contact%20and%20harmful%20if%20swallowed.

Is this the susbstance that caused panic amongst barristas for which the HSE published EPD01-2023?

There are limits in EH40 - WEL 0.02ppm, 0.07mg/m3 / STEL 0.1ppm, 0.36mg/m3

Which match the community exposure limit listed by the EU

Thanks Roundtuit

I search my copy of EH40 using the CAS Number and nothing turned up. I have just put diacetyl in, and it did turn up and the entry  that correct CAS number!

Weird

I always do a two way search of EH40 if the first gets no result - there are quite a few entries in EH40 which do not have a CAS #.

More frustratingly are the substances which get grouped e.g. Metals and their compounds, isocyanates etc.