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Acute toxicity Skin corrosion / Irritation Serious damage to eyes / Eye irritation Respiratory / Skin sensitisation Germ cell mutagenicity Carcinogenicity Reproductive toxicity Specific target organ toxicity - single exposure Specific target organ toxicity - repeated exposure Aspiration Endocrine disruption for human health
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Classification

Skin corrosion / Irritation

Mixture's pH

According to 3.2.3.1.2 of Annex I to CLP "... In the absence of any other information, a mixture is considered corrosive to skin (Skin Corrosion Category 1) if it has a pH ≤ 2 or a pH ≥ 11.5 ...". Therefore, if a mixture has such extreme pH it is classified as 'Skin Corr. 1'.

The generic cut-off value for Skin corrosion/irritation is 1 % (CLP, Annex I, Table 1.1). This means that if mixture consists of substances classified as Skin corrosion or Skin irritation each present at a concentration below 1 % and even if the sum of their concentrations is above 1 % the mixture will not be classified for Skin corrosion/irritation.

Non-additivity approach

In case of acids, bases, inorganic salts, aldehydes, phenols and surfactants the generic cut-off approach is not applicable, because many such substances are corrosive or irritant to the skin at concentrations < 1 %. A mixture containing such ingredients cannot be classified on the basis of the additivity approach. In this case Skin corrosion/irritation is calculated based on approach described in Annex I, 3.2.3.3.4.3 and Table 3.2.4 to CLP.

In the table below generic concentration limits of ingredients that trigger classification of the mixture as Skin corrosion/irritation are presented.

Ingredient Concentration in mixture Mixture classified as
Acid with pH ≤ 2 ≥ 1 % Skin Corr. 1
Base with pH ≥ 11.5 ≥ 1 % Skin Corr. 1
Other skin corrosive (sub-categories 1A, 1B, 1C or Category 1) ingredients ≥ 1 % Skin Corr. 1
Other skin irritant (Category 2) ingredient, including acids and bases ≥ 3 % Skin Irrit. 2

Additivity approach

The table below represents generic concentration limits of ingredients classified as Skin corrosion (Category 1, 1A, 1B or 1C) and Skin irritation (Category 2) that trigger classification of the mixture as Skin corrosion or Skin irritation where the additivity approach applies (CLP, Annex I, Table 3.2.3).

Sum of ingredients classified as Concentration triggering classification of a mixture as
Skin corrosion
(for selection (sub-)category see note)
Skin Irrit. 2
Skin Corr. 1A +
Skin Corr. 1B +
Skin Corr. 1C +
Skin Corr. 1      
≥ 5 % ≥ 1 % but < 5 %
Skin Irrit. 2 ≥ 10 %
10 × (Skin Corr. 1A +
          Skin Corr. 1B +
          Skin Corr. 1C +
     Skin Corr. 1)
+
Skin Irrit. 2
≥ 10 %

Note.

The below approach should be used to calculate Skin corrosion:

To classify mixture as Skin Corr. 1A concentrations only of following ingredients are added:
- 'Skin Corr. 1A'
If their sum is ≥ 5 % the mixture is classified as 'Skin Corr. 1A'.
To classify mixture as Skin Corr. 1B concentrations only of following ingredients are added:
- 'Skin Corr. 1A'   and
- 'Skin Corr. 1B'
If their sum is ≥ 5 % the mixture is classified as 'Skin Corr. 1B'.
To classify mixture as Skin Corr. 1C concentrations only of following ingredients are added:
- 'Skin Corr. 1A'   and
- 'Skin Corr. 1B'   and
- 'Skin Corr. 1C'
If their sum is ≥ 5 % the mixture is classified as 'Skin Corr. 1C'.
To classify mixture as Skin Corr. 1 concentrations only of following ingredients are added:
- 'Skin Corr. 1A'   and
- 'Skin Corr. 1B'   and
- 'Skin Corr. 1C'   and
- 'Skin Corr. 1'
If their sum is ≥ 5 % the mixture is classified as 'Skin Corr. 1'.

The below approach should be used to calculate Skin irritation:

If the sum of all ingredients with 'Skin Irrit. 2' is ≥ 10 % the mixture is classified as Skin Irrit. 2.
If mixture contains ingredients classified as Skin corrosion (sub-)categories 1A, 1B, 1C or 1 their concentration values must be summed and multiplied by 10. Additionally, if mixture contains ingredients with Skin irritation category 2 their concentration values (without multiplication) should be added. If final sum is ≥ 10 % the mixture is classified as Skin Irrit. 2.

For calculation the skin corrosion/irritation properties of the mixtures, only 'relevant ingredients' are taken into account.

The 'relevant ingredients' of a mixture are those which are present in concentrations ≥ 1 % (w/w for solids, liquids, dusts, mists and vapours and v/v for gases), unless there is a presumption (e.g. in the case of skin corrosive ingredients) that an ingredient present at a concentration < 1 % can still be relevant for classifying the mixture for skin corrosion/irritation (CLP, Annex I, 3.2.3.3.1).

If mixture contains an ingredient classified as 'Skin Corr. 1A' or 'Skin Corr. 1B' or 'Skin Corr. 1C' or 'Skin Corr. 1' or 'Skin Irrit. 2' at concentration below 1 % such ingredient is not taken into account because:
− its concentration is below cut-off limit 1 % (CLP, Annex I, table 1.1),
− it is not a 'relevant ingredient'.

Ingredients classified as Skin corrosion 1, 1A, 1B and 1C are also have influence on Serious eye damage and Eye irritation classification of a mixture.

Hierarchy of hazard categories

Hazard
Skin corrosion, category 1 (Skin Corr. 1: H314)
Skin corrosion, sub-category 1A (Skin Corr. 1A: H314)
Skin corrosion, sub-category 1B (Skin Corr. 1B: H314)
Skin corrosion, sub-category 1C (Skin Corr. 1C: H314)
Skin irritation, category 2 (Skin Irrit. 2: H315)

A more severe classification for a mixture overrides a less severe classification. For example, if ingredients of a mixture lead to classification both as skin corrosion category 1 (Skin Corr. 1) and skin corrosion sub-category 1A (Skin Corr. 1A) the category 'Skin Corr. 1' must be selected.

To select pictogram, signal word, hazard and precautionary statements please refer to Annex I, part 3, Table 3.2.5 of Regulation (EC) no 1272/2008 (CLP).

For mixture which may cause concern as a result of skin dryness, flaking or cracking but is not classified as Skin Irrit. 2: H315 supplemental information on the label should contains EUH066 - 'Repeated exposure may cause skin dryness or cracking' (CLP, Annex II, 1.2.4).

According to answer of European Chemical Agency in section Q&As, ID: 1138   "... When a mixture only contains one corrosive or irritant ingredient (acid or base) with an SCL, the mixture should be classified according to this SCL even if the pH of the mixture is extreme. However, the SCL reflects a situation where the mixture does not contain any other ingredient that might affect the classification for that endpoint. If other ingredients in the mixture affect the irritant/corrosive properties, this has to be taken into account...".

Example 1
Example 2
Example 3
Example 4
Example 5
Example 6
Example 7
Example 8

See also Example 2  in section Examples.