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Controlling impurities

Unilever employees in a laboratory

Slight impurities (known as ‘traces’ or ‘trace contaminants’) can occur in some products – either because they are naturally present in raw materials, or because they arise during the manufacturing process.

We want people to have complete trust in our brands. We work hard to keep our products as free from impurities as possible and have strict quality controls on the raw materials and ingredients we use, and in the manufacturing process.

The specifications we set ensure that the level of any impurities in our home, beauty and personal care products are as low as is reasonably achievable. This ensures that the amount of any trace contaminants present in our products are safe for people and the environment.

Some of the substances we are most often asked about are phthalates, mercury, 1,4-dioxane and benzene.


Phthalates are a family of chemicals that increase the flexibility and durability of plastics. They are commonly used in packaging materials, flooring, cables, luggage, sports equipment and medical devices.

We do not use phthalates in the making of our products, although very small traces, which are well within safety levels, may be present.

In line with our own standards of avoiding phthalates, we do not use Diethyl phthalate (DEP), which is a solvent used to mix fragrance ingredients. Instead, we use other approaches to bring together fragrance ingredients.

We always ensure that any phthalates we use in packaging are below the levels assessed as safe by regulatory authorities.

Mercury compounds

Mercury is a heavy, silvery-white metal that is liquid at room temperature. It has traditionally been used in some countries as a skin lightener. Exposure to high concentrations of certain forms of mercury can lead to allergic reactions, skin irritation or damage to the nervous system.

We do not add mercury compounds to any of our home, beauty and personal care products. We strictly control any unavoidable trace levels to be below 1 parts per million in the raw materials we use, such as talc. This is below the levels that are assessed as safe by regulatory authorities.

We support activities by the wider industry and regulatory authorities to reduce or prohibit the intentional use of mercury compounds in home and personal care products.


Home, beauty and personal care products can contain tiny quantities of a compound called 1,4-dioxane, which can form during manufacturing. Trace amounts of 1,4-dioxane also occur naturally in foods such as tomatoes, coffee and cooked chicken.

Regulators, including the Food and Drug Administration (FDA), the US agency responsible for safety in US food and drugs, have determined that the levels of 1,4-dioxane found in personal care products are not a risk to health. However, at high levels of exposure 1,4-dioxane is a possible human carcinogen and we therefore take care to minimise its levels by imposing stringent controls in the manufacturing process.

We ensure levels of 1,4-dioxane in our home, beauty and personal care products are well within safe parameters. For many years we have imposed a limit of 10 parts per million for our beauty and personal care products and 30 parts per million for our home care products. The levels reflect the different ingredients and product types. Where stricter limits are set by local authorities we comply with those regulations.


Benzene is a substance which is formed from both natural and man-made activities. It is not an ingredient we use in our products, although trace levels can sometimes occur due to its natural presence in certain raw materials.

We have strict quality controls in place that limit the presence of benzene in our products so that any traces found fall within safe levels.

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