Sodium Selenite

Sodium Selenite is considered a hazardous chemical – it has acute toxicity if inhaled or ingested, and leads to eye and skin irritation.

It’s listed under Hazard Class 6.1, which is the same class as arsenic, cyanide, lead and pesticides.

See the International Programme on Chemical Safety's page for more information: https://www.inchem.org/documents/icsc/icsc/eics0698.htm#:~:text=The%20substance%20is%20irritating%20to,Medical%20observation%20is%20indicated.&text=Evaporation%20at%2020%C2%B0C,%2C%20however%2C%20be%20reached%20quickly.

If we bring this into the building, it needs to be kept essentially quarantined away from everything else. When moving or using it, everything must be observed and signed off by Quality, and PPE such as filter respirator masks have to be worn.

It’s also extremely toxic to the environment so we have to be extremely careful that it is stored and disposed of correctly.

It is technically an approved form of selenium, but the risks are far too large that we will not use it. It is so toxic due to the high content of selenium – Sodium Selenite is 45% selenium, other forms in Access are 2% at most.

There is also a risk of this form not being blended properly – such a small amount gets used (e.g. 25g in an 80kg mix) that it’s hard to verify whether it’s dispersed evenly.

I would recommend R1159 L-Selenomethionine instead – this is selenium bonded to an amino acid so is more readily available. We tend to have this in stock all the time, and it’s much cheaper than the Sodium Selenite.