Hi Mr Curious

First Q is does the material meet the definition of "substance hazardous to health" as set out in COSHH Reg 2

“substance hazardous to health” means a substance (including a preparation)—

(a) which is listed in Part I of the approved supply list as dangerous for supply within the meaning of the CHIP Regulations and for which an indication of danger specified for the substance is very toxic, toxic, harmful, corrosive or irritant;

(b) for which the Health and Safety Commission has approved a maximum exposure limit or an occupational exposure standard;

(c) which is a biological agent;

(d) which is dust of any kind, except dust which is a substance within paragraph (a) or (b) above, when present at a concentration in air equal to or greater than—

(i) 10 mg/m3, as a time-weighted average over an 8-hour period, of inhalable dust, or

(ii) 4 mg/m3, as a time-weighted average over an 8-hour period, of respirable dust;

(e) which, not being a substance falling within sub-paragraphs (a) to (d), because of its chemical or toxicological properties and the way it is used or is present at the workplace creates a risk to health;

On the basis of what you have written unlikely to fall within sub-paragraphs (a) to (c) but may be caught by (d) or the catch-all (e) which is why for example water is subject to COSHH.

Will get more complicated if you process the material such that it creates other substance(s) hazardous to health either as an end product or as an intermediary.

Good luck, Peter

If it is a powder form then you would have to consider dust exposure.

However is the supplier statement correct? A lot of the early exemptions back in 2006 no longer apply.

As more data has become available over time the classification of hazards associated with substances has changed e.g. under ATP 14 the pigment Titanium Dioxide has acquired Carcinogen 2 / H351 based upon aerodynamic particle size

Cereal will be included as producing dust. How much dust depends on what you do with it. Note that, there  is a  difference between respirable and inhalable dust. Inhalable dust consists of the larger particles which may get to the back of your throat but often coughed out again while the respirable faction gets right into your lungs and is likely to stay there. How much of each type of dust is produced needs measuring by a competent person.  I am assuming that this cereal is intended for human consumption, so it won’t include any products dressed with herbicides etc. I am also assuming that the product has been carefully stored and  that there is no fungi growing on it-fungi being a source of mycotoxins.