According to the Consumer Council, most essential oil products fail to adequately inform consumers of allergens contained in the oils, which they say can cause allergic reactions and skin rashes. 

The Council tested 30 examples of scented essential oils in February and March this year. Oil fragrances included lavender, sweet orange and eucalyptus, and tests found the presence of ten different allergens, according to a council press release. Two samples contained as many as seven allergens.

Allergens such as limonene, found in essential oils, can cause irritation to the skin and the eyes, and when oxidized gives rise to the risk of contact allergies.

Essential oils of the citric fruit type, such as bergamot, contain furocoumarins which can absorb ultraviolet light. The free radical and inflammatory substances produced by these organic chemicals are known to cause injury to skin and lead to pain and rash akin to sunburn, the council warned.

The consumer watchdog also found that almost 90% of the essential oils tested did not identify the allergens on their labels.

Even when allergen information did feature on labeling, in four oils tested the allergens declared did not match actual allergens detected.

Of the 30 products tested, 14 offered no instructions on diluting the essential oils.

The council warned that essential oils are highly concentrated and should be diluted before use on skin to reduce the chance of allergic reactions.

Children, pregnant women, sufferers of hypertension, kidney disease and epilepsy, and people with open wounds are reminded to be extra cautious when using essential oil products.