In the back of our minds we all know that daily application of serum, moisturiser, primer, foundation, concealer, mascara *insert 12-step regime of choice* can't be all that good for us, but can they really be that bad? If internet hype is to be believed, well, yes - one more flick of mascara will most likely kill you. And don't even try googling the effects of sunscreen (beyond, ahem, protecting you from cancer).

But is there a case for reducing your cosmetics' chemical load, and are we actually at risk? The recent media storm surrounding triclosan - an endocrine-disrupting chemical found in antibacterial soap and toothpaste - is enough to give even the most cynical beauty addict cause for concern.

Should we be worried?

Buyer beware: the most dangerous ingredients in your beauty kit

"In general, no," says Dr Adam Sheridan, a Melbourne-based dermatologist and spokesperson for the Australasian College of Dermatologists. "The skincare industry in Australia is well regulated and most products available in Australia have been rigorously tested to ensure products are safe for frequent use and compatible with most skin types." According to a recent investigation by Choice, all products manufactured or imported into Australia are assessed by the Department of Health and Ageing's National Industrial Chemicals Notification and Assessment Scheme (NICNAS), plus listed ingredients are screened by the ACCC.

But does the NICNAS and ACCC know exactly how much night cream we slather on? Or have any idea how often we Netflix and sheet mask? Dr Sheridan assuages our "frequent use" fears: "The skin's primary function is to act as an extremely efficient biological barrier, keeping bad things out and good things in," he says. "The small amount of chemicals we may absorb from quality skincare is far less significant than the amounts we inhale or ingest."

What to avoid

Buyer beware: the most dangerous ingredients in your beauty kit

There are a few caveats, however - triclosan among them. "I strongly suggest avoiding methylisothiazolinone and methylchloroisothiazolinone, as these may cause allergic skin issues for some people," Dr Sheridan cautions. Both M-bombs are preservatives found in products like wet wipes, deodorants, moisturisers and cleansers that are known to cause dermatitis - to the point where they've been banned from leave-on products in Europe.

Furthermore: "Concerns have been raised regarding the ability of certain elements such as heavy metals (lead and mercury) and nanoparticle zinc in sunscreen to absorb through the skin and potentially accumulate in the body," Dr Sheridan adds. "Caution is advised when applying products to very large areas frequently (i.e. legs and back) and especially where the skin barrier is compromised by medical conditions such as dermatitis or burns."

The problem with online shopping

Buyer beware: the most dangerous ingredients in your beauty kit

There's an assumption that the beauty behemoths are out to rip us off, filling their pretty shiny products with pretty nasty - but profitable - fillers, but it's the more obscure brands you're buying online that you have to watch out for. Choice's report found that the major international beauty brands have eradicated many potentially harmful ingredients from their products, including dibutyl phthalate, toluene and butylated hydroxyanisole (BHA).

"Brands like L'Oreal go through so much to get their active products approved but then something else can just get imported without going through the same channels," says Dr Sheridan. "You order it on your computer and bring it into Australia, but you don't know the biosecurity of the product. It's a bit of a risk."

Is natural best?

Buyer beware: the most dangerous ingredients in your beauty kit

Natural products are another misnomer - far be it from us to start hating on Aesop body wash or jojoba oil, but you simply can't assume that all '100% natural' claims are legit (just look what happened with WEN conditioner). "In Australia currently, there's no legal definition of organic or natural, so different certifications mean different things," explains Dr Sheridan. "It's best to look for an indication on a product that it has been dermatologically tested."

The take-home
Next time you're restocking your beauty supplies, keep these dermatologist-approved safeguards in mind: provided they're from a reputable brand, free of the aforementioned nasties and dermatologically tested, there's every chance your cult-status serums and can't-live-without concealers are safe.

Buyer beware: the most dangerous ingredients in your beauty kit