Archive for April, 2013


Titanium Dioxide in Foods and Cosmetics

Posted by Luca Willington

It’s everywhere, from candies to paints, to toothpaste, sunscreens and mineral foundation. Is it safe? And does titanium dioxide (TiO2) equates to nanoparticles?

For years I entertained the reassuring idea that most TiO2 applications involve fairly large particles of this substance. After all it’s only sunscreens that require invisible, nano-form TiO2. The food industry uses this mineral as a colouring agent – to make the milk look  whiter and the marshmallows shimmery. If it’s opacity and coverage you’re after, nano particles, being transparent, are useless. The same applies to most cosmetic applications – mineral make up, toothpaste and many other toiletries. So manufacturers don’t need TiO2 in nano form for anything except sunscreens. Right? Well, not quite. Although nano TiO2 is not useful as a colouring agent, recent research has nevertheless found that about 36% the particles in food grade TiO2 is nano size. Research info

In view of this find, the question about nano TiO2 becomes even more important.

TiO2 nanoparticles in food

There is conflicting research data on the effects of ingested TiO2 nanoparticles. A few experiments have shown that ingested titanium dioxide does not get absorbed from the guts into the bloodstream. These are the experiments which have informed the decisions of food industry regulators to approve TiO2 as a colouring agent. More info Read the rest of this entry »


Essential Oils and Skin Care

Posted by Luca Willington

They smell good, they are extracted from plants, so pretty much everyone would agree essential oils are natural. How good are they for your skin?

Despite their name, essential oils are not actually oils – they are not composed of lipids like the vegetal or mineral substances we class as oils. They are, in fact, aromatic volatile substances made of chemical compounds responsible for the distinctive fragrance of the plant they originate from.

Essential oils have been used for hundreds of years in aromatherapy. Their effects are largely due to their smell - relaxing, refreshing, uplifting etc, although some physiological effects have been observed. E.g. linalool, one of the main compounds of lavender essential oil has been shown to decrease systolic blood pressure and slightly lower skin temperature, but these effects were too slight to be noticed by the subjects in this research. More info about this research

The use of essential oils in skin care is a matter of heated debate, with essential oil manufacturers and aromatherapists strongly defending them, while a number of skin care experts argue against all fragrance ingredients in skin care products, essential oils included.

Here are a couple of objections raised against:

  1. Geraniol – one of the main aromatic compounds in rose and geranium essential oils. Geraniol is “a skin sensitizer in humans and mice” according to the U.S. Environmental Protection Agency. More info about this report
  2. Linalool and limonene – the most common essential oil compounds, present in large proportions in Lavender and all citrus essential oils ( Bergamot, Grapefruit, Lemon, Lime, Manadarin and Orange). Both linalool and limonene oxidize on air exposure. The pure compounds do not cause any iritation, but “autoxidation of the fragrance terpenes linalool and R-limonene increases irritation” have concluded a group of Swedish researchers. The effects were similar in dermatitis patients and controls. More info about this research 

The irritating potential of these compounds will naturally decrease with concentration. Aromatherapists observe fairly strict limits with regards to the amounts of essential oils in their massage mixtures.  The Cosmetic Safety Regulations do not impose a maximum limit on essential oil compounds in skin care products. All they require is that the aromatic compounds are listed separately at the end of ingredient lists so that consumers are aware of their presence.

Essential oil critics argue that essential oils should be enjoyed for what they are i.e. fragrances, therefore – when it comes to cosmetics – their place is in perfumes and not in moisturisers.

What do you think about essential oil use in skin care products? Do you like cosmetics containing essential oils or do you prefer unscented products?