Schiff's bases and aldehydes or ketones safety

[jperezcejuela]

Hi everyone.
As I have no great knowledge of chemistry I would like to know if the combinations of Schiff's bases such as AURANTIOL with other aldehydes or ketones could have negative effects on skin or other aspects of health, or the reactions would affect only to the composition in terms of condensation, water release, etc.
Thanks

 

[pkiler]

No health effects.

 

[RomanB]

Health concerns of individual parts of Schiff’s bases and acetals should be considered. So, if hydroxycitronellal is limited due to health concerns, then its dimethyl acetal or base with indole pose the same risk.

 

[ourmess]

Health concerns of individual parts of Schiff’s bases and acetals should be considered.

Why? Health concerns of chlorine are not considered when you're using table salt.

 

[David Ruskin]

Whether or not you agree, the safety considerations of Schiff bases are the safety considerations of the components of the Schiff bases. Thus Aurantiol is treated the same as hydroxycitronellal.

 

[jperezcejuela]

I understand that we should bear in mind that for the case of Aurantiol for example restrictions exist for hidroxycritronellal as one of its components, but I get that there are no health concerns because of the combinations of Aurantiol(as an example) with other aldehydes or ketones. Thank you all

 

[RomanB]

Why? Health concerns of chlorine are not considered when you're using table salt.

Because it is very improbable to separate chlorine from sodium on skin to get some poisonous gas and vigorously burning metal. On the other hand acetals and Schiff bases are unstable and decompose readily.

If you really care about your customers, using easily decomposed substances to cover use of their constituents is a dirty trick. It allows to circumvent formal prohibitions, but you still can harm people.

 

[jfrater]

Because it is very improbable to separate chlorine from sodium on skin to get some poisonous gas and vigorously burning metal. On the other hand acetals and Schiff bases are unstable and decompose readily.

If you really care about your customers, using easily decomposed substances to cover use of their constituents is a dirty trick. It allows to circumvent formal prohibitions, but you still can harm people.

Bear in mind that IFRA includes aurantiol and other schiff bases in their restrictions on hydroxycitronellal - so you can't avoid the restrictions using schiff bases. They even include a nice little chart in the regulation to help you determine levels:

 

[ourmess]

On the other hand acetals and Schiff bases are unstable and decompose readily.

Fair enough.

 

[jsweet]

I'm pretty sure I found a post on here from a while back in which someone was making a benzaldehyde schiff base in order to "get around IFRA." Interesting that aurantiol is listed by IFRA, but not all aldehydes are listed in schiff base forms.

 

[RomanB]

Bear in mind that IFRA includes aurantiol and other schiff bases in their restrictions on hydroxycitronellal - so you can't avoid the restrictions using schiff bases. They even include a nice little chart in the regulation to help you determine levels:

View attachment 328570

But there are also ethyl anthranilate, n-propyl anthranilate and they are not listed.

 

[Culpa Ire]

Interesting that aurantiol is listed by IFRA, but not all aldehydes are listed in schiff base forms.

Of the two I just checked, cinnamaldehyde and benzaldehyde are both addressed in Annex II, like the Aurantiol example Jamie provided.

It’s likely going to mention only those that are restricted as a single molecule, surely. Maybe I misunderstood your point.

 

[jsweet]

Of the two I just checked, cinnamaldehyde and benzaldehyde are both addressed in Annex II, like the Aurantiol example Jamie provided.

It’s likely going to mention only those that are restricted as a single molecule, surely. Maybe I misunderstood your point.

That's right, I should have been clearer that IFRA does mark it on common schiffs, I was thinking of safranal which may not even have a CAS as a schiff base 😅

 

[Culpa Ire]

was thinking of safranal which may not even have a CAS as a schiff base

You have me wondering what a Schiff of that would smell like now. Only one way to find out!

 

[pkiler]

That's right, I should have been clearer that IFRA does mark it on common schiffs, I was thinking of safranal which may not even have a CAS as a schiff base 😅

No, a schiff base of safranal does not have a cas, and smells great!

 

[jsweet]

No, a

schiff base of safranal does not have a cas, and smells great!

I have a 4ml concoction of it that does smell really good. I assume that there is a significant amount of pure safranal still in mine, but I do wonder if the pure schiff would escape regulation given that it is off the radar.

 

[steventeddy]

I have a 4ml concoction of it that does smell really good. I assume that there is a significant amount of pure safranal still in mine, but I do wonder if the pure schiff would escape regulation given that it is off the radar.

I don't think so if you follow IFRA's guidance. The following essentially is a reiteration of what David, Jamie, and Roman have brought up in their respective posts. Here's a screenshot from page 16 of the 49th amendment's Guidance for the use of IFRA Standards regarding Schiff bases.