Chromium in Leather: Is Chrome-Tanned Leather Safe to Wear? Cr(III), Cr(VI) and What Tests Show

Chrome-tanned leather is made with chromium(III), the form of chromium that is much less toxic than chromium(VI). The worry is chromium(VI): it can form in some chrome-tanned leather, and in the EU skin-contact leather must stay below 3 mg/kg of it. A lab test, EN ISO 17075, shows which side of that line a given leather falls on.

This page is part of our guide to leather tanning and production. It explains the chemistry in plain English and lists what you can ask a maker. For how chrome tanning works step by step, see chrome-tanned leather: how it is made.

Chromium(III) and chromium(VI): two different substances

"Chromium" on its own tells you very little. The two forms behave differently in the body, and only one of them is used to tan leather.

One study of tannery wastewater puts chromium(VI) at about a hundred times more toxic than chromium(III). The health descriptions above follow the CDC's chromium fact sheet and describe chromium in general. They are not a test result for any jacket.

Where chromium(VI) can come from

The tanning bath uses chromium(III). Chromium(VI) can form afterward, when chromium(III) in the leather oxidizes.

A 2001 trade-journal study from a chemical maker's laboratories describes the mechanism. Oxygen reacts with double bonds in the oils and other chemicals added after tanning, and the reaction is sped up by heat and UV light. In that study, heavy chrome retanning, a high pH at neutralizing and sulfited fish oils all raised chromium(VI).

The same study found that plant tannins lowered it. Its authors advise avoiding chrome retanning, neutralizing to pH 5 or below and using protected fatliquors. This is one old study on uncolored leather, so treat it as an explanation of the mechanism, not as proof about today's leather.

Wikipedia adds that boiling and sun drying can oxidize chromium(III) into chromium(VI). Its example is tannery waste in Bangladesh, not finished leather.

The limit and the test

The European Union restricts chromium(VI) in leather under Commission Regulation (EU) No 301/2014. Leather articles and articles with leather parts that touch the skin may not be sold in the EU at 3 mg/kg (0.0003% by weight) of dry leather or above. The rule has applied since 1 May 2015, and second-hand articles already in use in the EU before that date are exempt.

The regulation gives its reason: chromium(VI) in skin-contact leather can cause new cases of skin sensitization and trigger allergic reactions. People who are already sensitized may react at lower levels. It expects the limit to cut new chromium(VI) allergic dermatitis by 80%.

The regulation names EN ISO 17075 as the only internationally recognized method for chromium(VI) in leather. The method's determination limit is 3 mg/kg. So a clean result means "below 3 mg/kg", not "zero".

This page describes the EU rule because it is the one we read. We have not read an equivalent US rule, so we make no claim about one.

Do chrome-tanned jackets pass?

The sources we read do not say that chrome-tanned leather as a class is safe or unsafe. They say the amount of chromium(VI) depends on how the leather was made and finished, and that the EU sets a limit you can test against.

Leather Collection's jacket, glove and race-suit pages name the animal, but they do not state the tanning method. We therefore cannot tell you how any particular Leather Collection jacket is tanned from its product page. Ask before you buy if it matters to you. For the hides themselves, see Leather Collection's guide to leather types.

What to ask a maker

Questions that give a usable answer:

1. Is the leather tested for chromium(VI) to EN ISO 17075, and can I see the report?
2. Does the report cover this batch, and how recent is it?
3. Was the tannery audited under the Leather Working Group standard, which includes chromium(VI) management among its 17 sections?
4. If I have a known chromium allergy, can you tell me the tannage?

A maker who cannot answer the first two questions may simply not have tested.

If you want to avoid chrome altogether

Other tannages exist, such as vegetable tanning and the aldehyde or metal-salt "wet white" methods. Our page on vegetable-tanned leather covers the plant-based route. We plan a page on metal-free and chrome-free leather.

On the tannery side, about 40% of the chromium used in industrial tanneries ends up in the wastewater, according to one 2021 study. That is a separate question from skin contact; see how environmentally friendly is leather.

FAQ

Is chrome-tanned leather toxic? The tanning agent, chromium(III), is much less toxic than chromium(VI). Chromium(VI) can form in leather under some conditions, which is why the EU limits it in skin-contact leather.

Can chromium(III) in a jacket turn into chromium(VI)? It can oxidize, helped by heat, UV light and some fatliquors, as the 2001 study describes. The sources we read did not test washing with soap, so we do not answer that part.

Is there a test I can ask for? Yes: EN ISO 17075, the method the EU regulation names.

Does chromium in leather cause allergies? Chromium(VI) can cause allergic skin reactions, and some people are sensitive to chromium(III) too. If you have a known allergy, ask your doctor, not a leather guide.