Hexavalent chromium toxicity for consumer and end-product?

[Joshm839]

Hello

I've been reading a bit on the internet about the use of chrome for various applications such as item plating, vehicles, tools, leather work and even how its used in supplements. But I need some further help regarding chromium (specfically toxic hexavalent chrome) interaction for end-user/consumer side.

It seems chromium is safe when its Cr3 (trivalent) and is even beneficial for humans, but it seems Cr6 hexavalent chromium is the complete opposite and is even labeled as a carcinogen.

Upon doing some rough research on how Cr6 finds its way to the consumer side and the impact, I've encountered the following details:

Stainless steel items - Hexavalent chromium is a non-issue unless under extreme conditions (like welding). Even cooking with stainless steel is safe for the most part since temps don't really get to the extremes of welding temps.

Chrome-plated items - Typically a non-issue whether item (such as a stainless steel shelf plated with chrome) is bathed in trivalent or hexavalent chrome during plating process. End-user item will just remain metallic Cr0 plated and non-toxic. BUT, there is still a possibility of hexavalent chromium staying on end product by accident, typically if the rinsing wasn't conducted properly, cross-contamination or other mishaps.

Chromate conversion coating - From what I understand, this process is a bit different than just chrome-plating items. This typically involves coating a finished product with trivalent chromium or hexavalent chromium, especially when performing zinc plating, brass plating, etc. as they need corrosion protection. If an item is coated in hexavalent chromium, this WILL result in the end user/consumer coming into contact with the chemical from what I understand.

Leather working - In order to prevent leather hides from rotting, two tanning processes are used: vegetable tanning and chrome tanning. Chrome tanning is the most common tanning and is typically done with trivalent chromium. But there have been instances where traces of hexavalent chrome have still been detected on consumer leather products, typically from questionable tanneries. From what I've somewhat understood, Cr3 on leather also has a higher chance of oxidation to Cr6 although this doesn't sound too right.

Therefore, given all this (and please correct the hell out of all this), how much of an impact is hex chrome for end-users and how would we go about it?

Out of these, hex chrome interaction via leather is perhaps the most prominent (especially via leather wearables) followed by chromate conversion coating since I believe that process used on stuff like tools, bolts, doorknobs, car parts, etc. Most of the industry seems to be transitioning to trivalent for applications due to stricter regulation, but this is all fairly recent and is not a catch all. How would an end-user go about handling potential hex chromium exposure through door knobs, vintage items, wearing leather, etc., especially for items made pre-strict regulation or in countries where regulation isn't even followed? Is there a method for washing off or handling hex chrome contamination at home? Is there a "safe" level of exposure?

Sorry for the ramble and I appreciate your time.