I've been looking into skincare and makeup, reading labels and doing some research of course. What I've noticed is when I google a product and read lots of ingredients, there are mostly-if not completely-good things. Not a problem in the slightest. But there will be forums and articles deterring consumers from certain products that actually work very well. Their reasoning for why it's bad is completely unscientific and illogical, like "It contains silicones!". It's like people learn a new word like "silicone" and spread fear-mongering like it's the Gospel! So, I need to know exactly what is bad to put on your face (in general, because everyone's skin is different).

14 minutes ago, Sarae.the.wannabe.chemist said:

I've been looking into skincare and makeup, reading labels and doing some research of course. What I've noticed is when I google a product and read lots of ingredients, there are mostly-if not completely-good things. Not a problem in the slightest. But there will be forums and articles deterring consumers from certain products that actually work very well. Their reasoning for why it's bad is completely unscientific and illogical, like "It contains silicones!". It's like people learn a new word like "silicone" and spread fear-mongering like it's the Gospel! So, I need to know exactly what is bad to put on your face (in general, because everyone's skin is different).

If you think for a moment you will realise it is impossible to answer this question. There are innumerable substances that are not good to put on the skin. 

@exchemist So I guess it's a trial-and-error kinda thing, huh?

1 hour ago, Sarae.the.wannabe.chemist said:

@exchemist So I guess it's a trial-and-error kinda thing, huh?

Well you would have to provide a list of the ingredients you have found are used, or which you think might be considered, and then perhaps one could comment on each. But without that it's completely open-ended. 

If one wanted to be systematic, one would need to 1) list out all ingredients and their respective concentrations. 2) identify all toxicological data for each ingredient and sort by level of evidence. There are different levels of evidence ranging e.g. from cell cultures, which can be fairly far away for some toxic indicators, to animal tests to evidence in humans. The latter is usually the best but they are rare as we do not purposefully harm folks (hopefully). 3) identify evidence for trickier aspects of toxicity, such as long-term use (e.g., evidence for bioaccumulation, carcinogenic effects, etc.) 4) estimate a threshold value that can be generally considered to be safe 5) compare point 1) with all these aspects and provide a best estimate of potential harm.

The toxicological knowledge will evolve over time if people do more research.

2 hours ago, Sarae.the.wannabe.chemist said:

@exchemist So I guess it's a trial-and-error kinda thing, huh?

It depends in what one means by bad, and the individual. Something could be “bad” because of some ethical concern or it could be “bad” because it irritates the skin of some individuals.

Something that’s generally harmful would likely be discovered quickly, and regulation usually precludes its use*.

(*offer no longer valid in the US)

@exchemist That's exactly what I'm doing. I take the systematic route because I wouldn't be me if I didn't do things the long, hard, and mentally straining way (lol). I actually have entire notebooks dedicated to these things, including food science (hence my previous questions. Can you say "nerd"? ha). 

@swansont I mean bad as in:

-sensitizing

-irritating

-destructive to the skin barrier

-comedogenic

etc.

In general, cosmetics and body care products are relatively benign since anything that causes obvious problems is quickly restricted or taken off the market. It would be a lot easier to discuss particular ingredients because there are so many (I have several hundred chemicals just for making body oils and fragrances).

@npts2020 Well I wanted to, but I was hesitant to because I figured the things I would put are already researched by me (with reliable sources like the CIR and NIH), so it would be pointless to ask about those ingredients. I was really coming here in hopes of someone telling me about ingredients I may or may not know about. I have received an answer from @exchemist.  He said the question is, like, impossible to answer. But feel free to drop some knowledge if you want!

1 hour ago, Sarae.the.wannabe.chemist said:

@swansont I mean bad as in:

-sensitizing

-irritating

-destructive to the skin barrier

-comedogenic

etc

That’s why they do testing. On animals, sometimes, though that’s less common than in the past. In the US the companies are required to determine that ingredients are safe.

https://www.fda.gov/cosmetics/cosmetics-science-research/product-testing-cosmetics

AFAIK, minor issues, and ones that vary between individuals (e.g. allergies) aren’t strictly a safety issue. Something could be an irritant if you use it too often, and as long as that’s disclosed, it’s allowed.

52 minutes ago, Sarae.the.wannabe.chemist said:

I was really coming here in hopes of someone telling me about ingredients I may or may not know about.

How in the world are we supposed to know what ingredients you don't know about unless you tell us what you do know about?

 

53 minutes ago, Sarae.the.wannabe.chemist said:

He said the question is, like, impossible to answer.

Correct. Unless you bother to actually do some of the work yourself and be more specific in your question.

 

@zapatos Ha! I didn't mean you were supposed to know what I'm thinking lol! Should've cleared that up. I meant I expected someone to list off some to "beware of __" ingredients. 

Lead used to be a common in cosmetics. That should definitely be avoided. Similarly, mercury has been shown to be a bad idea is cosmetics.

Pthalates and parabens are common ingredients that are hormone disruptors.  I have a relative who works in pharmacy and says Walgreens et al are removing products that contain these.  There's a list out there of cosmetic additives with known carcinogenic effect or reproductive effect, called The Dirty Dozen, which you can google.  

I noticed the last tube of hand lotion I bought at Walgreens had ingredients info that made note of the absence of parabens and pthalates.  

 

I was going to mention phthalates since that is the only one I frequently use (specifically diethyl phthalate) that, if I am not mistaken, are banned in the EU for cosmetic uses but not in the US.

On 4/7/2025 at 12:44 AM, zapatos said:

Lead used to be a common in cosmetics. That should definitely be avoided. Similarly, mercury has been shown to be a bad idea is cosmetics.

Antimony in the form of stibnite, Sb₂S₃, as well as lead in the form of galena, PbS, both seem to have been used in kohl, traditional Middle Eastern eyeliner.

Antimony, being below arsenic in the Periodic Table, can poison you in a similar way, though it is far less toxic.

Antimony, being below arsenic in the Periodic Table, can poison you in a similar way, though it is far less toxic.

If I take a position that is anti-antimony, does that just make my view....mony?

If I take a position that is anti-antimony, does that just make my view....mony?

😁

Peace, victory, spaghetti, volume, vanadium and 2 to you as well, brother.

Edited April 9Apr 9 by TheVat

If I take a position that is anti-antimony, does that just make my view....mony?

It makes your view superstitious. Well, maybe not superstitious, but certainly a little bit stitious.

It makes your view superstitious. Well, maybe not superstitious, but certainly a little bit stitious.

Or a tad cilious?

Edited April 9Apr 9 by geordief

For skin care products (as opposed to cosmetics), Dermatologists used to prefer Neutrogena back in the day. Currently many of them prefer La Roche-Posay.

Edited July 29Jul 29 by LuckyR
Misspell

Keep in mind that amounts and 'strength' of the various chemical ingredients also matter.

Toothpaste, for example, may contain Fluorides, Peroxides, Bicarbonate, and various surfactant soaps.
The MSDS of all these will tell you they are not good.

Similarly, cosmetics often contain Peroxides as a 'drying' agent for the skin.
20% hydrogen Peroxide will burn skin and leave a white ( no color ) contact patch, and as little as 3% will cause your eyes to immediately go 'blood-shot' if you mistake the storage with the disinfecting solution for your soft contact lenses ( personal experience from over 30 yrs ago ).

On 4/6/2025 at 7:24 PM, exchemist said:

Well you would have to provide a list of the ingredients you have found are used, or which you think might be considered, and then perhaps one could comment on each. But without that it's completely open-ended. 

A particular bugbear of mine is hydroquinone, particularly in the context of 'skin whitening' cosmetic products. I believe there are some controls on its use in Europe and the US. But not so in Nigeria, to the extent that when I buy soap for myself, I really have to scan the contents listing. I find its purpose saddening and definitely do not require its intended effects myself.

37 minutes ago, MigL said:

Similarly, cosmetics often contain Peroxides as a 'drying' agent for the skin.
20% hydrogen Peroxide will burn skin and leave a white ( no color ) contact patch, and as little as 3% will cause your eyes to immediately go 'blood-shot' if you mistake the storage with the disinfecting solution for your soft contact lenses ( personal experience from over 30 yrs ago ).

I can certainly identify with this experience. After over 40 years of contact lens wear, I began to develop significant allergic reactions to the solutions (or possibly something else like protein residues) and had to give up and go back to wearing specs.

Edited August 5Aug 5 by sethoflagos
Removed diagnosis beyond my pay grade

18 minutes ago, sethoflagos said:

A particular bugbear of mine is hydroquinone, particularly in the context of 'skin whitening' cosmetic products. I believe there are some controls on its use in Europe and the US. But not so in Nigeria, to the extent that when I buy soap for myself, I really have to scan the contents listing. I find its purpose saddening and definitely do not require its intended effects myself.

Hmm, I didn't know hydroquinone could be used for that. It's a mild reducing agent (oxidising to benzoquinone), but I see it works as a skin lightener by decreasing melanin production in some way. Not clear how exactly. I do recall the ads for skin lightening concoctions when I was in Dubai in the 80s, aimed at the substantial population from the Indian subcontinent.

P.S. Quite funny that my 2 finger salute to @TheVat from 4 months ago still appears as a thumbnail against this thread, as if that is the prime reason anyone might want to look at it. Absurd piece of thinking by whoever it was that designed the software - just because it was a picture. This forum is not Snapchat.🙄

Edited August 5Aug 5 by exchemist