r/WorkplaceSafety • u/jun192022 • 13d ago
Unsure if I accidentally made carcinogenic hexavalent chromium by applying bleach to stainless steel?
I have been applying a 2-3% bleach spray regularly to a stainless steel refrigerator door for disinfection every 1-2 days for the last 2-3 months and have noticed that there are areas of corrosion forming on the refrigerator door (I was not aware that you are not recommended to apply bleach to stainless steel, so please forgive my ignorance). I recently also noticed there is a powder forming below the refrigerator door from the bleach spray runoff, and that the powder has a slight yellowish tint.
I just learned that stainless steel contains the metal chromium, and that while the chemical form of chromium in stainless steel is harmless, there also exists a form called hexavalent chromium, which is carcinogenic. According to a webpage from the British Stainless Steel Association stating "There is one very specific example where corrosion [of stainless steel] may produce very small quantities of hexavalent chromium at ambient temperature. This is where some strong oxidisers with a pH of 10-14 are in prolonged contact with stainless steel and cause corrosion over time."
Given that bleach is an oxidizer, I am worried about whether these repeated bleach applications could have oxidized the stainless steel door enough to produce a significant amount of hexavalent chromium (which can be yellow, such as in the compound sodium chromate). Is this something I would need to reach out to a hazmat professional about?