These may not be as toxic as those in insecticidal head lice lotions. But today’s shampoos and conditioners often contain a complex cocktail of artificial additives and synthetic preservatives.

And although manufacturers claim these chemicals are completely harmless, an increasing number of studies are showing that we may have underestimated the cumulative effect these compounds are having on our bodies – particularly on young children.

But not all products labelled ‘natural’ are as chemical-free as they may appear. So it’s worth reading the list of ingredients. Many conditioners sold as ‘herbal’ contain chemicals which wouldn’t be found in truly natural products.

Some of the chemical additives found in ‘natural’ hair care products are designed to extend shelf life – an important factor in keeping costs down. Or to create artificial fragrances and colouring. (Many children don’t like the smell of neem oil.)

Sodium laurel sulphate is used in many popular shampoos as a cheap foaming agent. Yet recent studies show it can pose serious health hazards. Synthetic preservatives called parabens are also widely used. These have been linked to a wide range of health problems, including breast cancer.

Hair care manufacturers spend huge promotional budgets persuading us to use their products. So it’s not surprising that they’re keen to play down any potential risks. But the question more and more consumers are asking is “Why take the risk?”.