Regulation (EC) No 1272/2008 of the European Parliament and of the CouncilDangos y teitl llawn

[F1 3.2. Skin corrosion/irritation U.K.

3.2.1. Definitions and general considerations U.K.

3.2.1.1.

• Skin corrosion means the production of irreversible damage to the skin; namely, visible necrosis through the epidermis and into the dermis, following the application of a test substance for up to 4 hours. Corrosive reactions are typified by ulcers, bleeding, bloody scabs, and, by the end of observation at 14 days, by discolouration due to blanching of the skin, complete areas of alopecia, and scars. Histopathology shall be considered to evaluate questionable lesions.

• Skin irritation means the production of reversible damage to the skin following the application of a test substance for up to 4 hours.

3.2.1.2. In a tiered approach, emphasis shall be placed upon existing human data, followed by existing animal data, followed by in vitro data and then other sources of information. Classification results directly when the data satisfy the criteria. In some cases, classification of a substance or a mixture is made on the basis of the weight of evidence within a tier. In a total weight of evidence approach all available information bearing on the determination of skin corrosion/irritation is considered together, including the results of appropriate validated in vitro tests, relevant animal data, and human data such as epidemiological and clinical studies and well-documented case reports and observations (see Annex I, Part 1, Sections 1.1.1.3, 1.1.1.4 and 1.1.1.5). U.K.

3.2.2. Classification criteria for substances U.K.

Substances shall be allocated to one of the following two categories within this hazard class:

(a)

Category 1 (skin corrosion)

This category is further subdivided in three sub-categories (1A, 1B, 1C). Corrosive substances shall be classified in Category 1 where data is not sufficient for sub-categorisation. When data are sufficient, substances shall be classified in one of the three sub-categories 1A, 1B, or 1C (see Table 3.2.1.)

(b)

Category 2 (skin irritation) (see Table 3.2.2).

3.2.2.1. Classification based on standard animal test data U.K.

3.2.2.1.1. Skin corrosion U.K.

3.2.2.1.1.1. A substance is corrosive to skin when it produces destruction of skin tissue, namely, visible necrosis through the epidermis and into the dermis in at least one tested animal after exposure for up to 4 hours. U.K.

3.2.2.1.1.2. Corrosive substances shall be classified in Category 1 where data is not sufficient for sub-categorisation. U.K.

3.2.2.1.1.3. When data are sufficient substances shall be classified in one of the three sub-categories 1A, 1B, or 1C in accordance with the criteria in Table 3.2.1. U.K.

3.2.2.1.1.4. Three sub-categories are provided within the corrosion category: sub-category 1A — where corrosive responses are noted following up to 3 minutes exposure and up to 1 hour observation; sub-category 1B — where corrosive responses are described following exposure greater than 3 minutes and up to 1 hour and observations up to 14 days; and sub-category 1C — where corrosive responses occur after exposures greater than 1 hour and up to 4 hours and observations up to 14 days. U.K.

Table 3.2.1
Skin corrosion category and sub-categories
a See the conditions for the use of Category 1 in paragraph (a) of Section 3.2.2.
Category	Criteria
Category 1 a	Destruction of skin tissue, namely, visible necrosis through the epidermis and into the dermis, in at least one tested animal after exposure ≤ 4 h
Sub-Category 1A	Corrosive responses in at least one animal following exposure ≤ 3 min during an observation period ≤ 1 h
Sub-Category 1B	Corrosive responses in at least one animal following exposure > 3 min and ≤ 1 h and observations ≤ 14 days
Sub-Category 1C	Corrosive responses in at least one animal after exposures > 1 h and ≤ 4 h and observations ≤ 14 days

3.2.2.1.1.5. The use of human data is discussed in Sections 3.2.1.2 and 3.2.2.2 and also in Sections 1.1.1.3, 1.1.1.4 and 1.1.1.5. U.K.

3.2.2.1.2. Skin irritation U.K.

3.2.2.1.2.1. A substance is irritant to skin when it produces reversible damage to the skin following its application for up to 4 hours. The major criterion for the irritation category is that at least 2 of 3 tested animals have a mean score of ≥ 2,3 and ≤ 4,0. U.K.

3.2.2.1.2.2. A single irritation category (Category 2) is presented in Table 3.2.2, using the results of animal testing. U.K.

3.2.2.1.2.3. Reversibility of skin lesions is also considered in evaluating irritant responses. When inflammation persists to the end of the observation period in 2 or more test animals, taking into consideration alopecia (limited area), hyperkeratosis, hyperplasia and scaling, then a material shall be considered to be an irritant. U.K.

3.2.2.1.2.4. Animal irritant responses within a test can be variable, as they are with corrosion. A separate irritant criterion accommodates cases where there is a significant irritant response but less than the mean score criterion for a positive test. For example, a test material might be designated as an irritant if at least 1 of 3 tested animals shows a very elevated mean score throughout the study, including lesions persisting at the end of an observation period of normally 14 days. Other responses could also fulfil this criterion. However, it should be ascertained that the responses are the result of chemical exposure. U.K.

Table 3.2.2
Skin irritation category a
a Grading criteria are understood as described in Regulation (EC) No 440/2008.
Category	Criteria
Irritation (Category 2)	(1) Mean score of ≥ 2,3 and ≤ 4,0 for erythema/eschar or for oedema in at least 2 of 3 tested animals from gradings at 24, 48 and 72 hours after patch removal or, if reactions are delayed, from grades on 3 consecutive days after the onset of skin reactions; or (2) Inflammation that persists to the end of the observation period normally 14 days in at least 2 animals, particularly taking into account alopecia (limited area), hyperkeratosis, hyperplasia, and scaling reactions; or (3) In some cases where there is pronounced variability of response among animals, with very definite positive effects related to chemical exposure in a single animal but less than the criteria above .

3.2.2.1.2.5. The use of human data is discussed in Sections 3.2.1.2 and 3.2.2.2 and also in Sections 1.1.1.3, 1.1.1.4 and 1.1.1.5. U.K.

3.2.2.2. Classification in a tiered approach U.K.

3.2.2.2.1. A tiered approach to the evaluation of initial information shall be considered, where applicable, recognising that not all elements may be relevant. U.K.

3.2.2.2.2. Existing human and animal data including information from single or repeated exposure shall be the first line of evaluation, as they give information directly relevant to effects on the skin. U.K.

3.2.2.2.3. Acute dermal toxicity data may be used for classification. If a substance is highly toxic by the dermal route, a skin corrosion/irritation study is not practicable since the amount of test substance to be applied considerably exceeds the toxic dose and, consequently, results in the death of the animals. When observations are made of skin corrosion/irritation in acute toxicity studies and are observed up through the limit dose, these data may be used for classification, provided that the dilutions used and species tested are equivalent. Solid substances (powders) may become corrosive or irritant when moistened or in contact with moist skin or mucous membranes. U.K.

3.2.2.2.4. In vitro alternatives that have been validated and accepted shall be used to make classification decisions. U.K.

3.2.2.2.5. Likewise, pH extremes like ≤ 2 and ≥ 11,5 may indicate the potential to cause skin effects, especially when associated with significant acid/alkaline reserve (buffering capacity). Generally, such substances are expected to produce significant effects on the skin. In the absence of any other information, a substance is considered as corrosive to skin (Skin Corrosion Category 1) if it has a pH ≤ 2 or a pH ≥ 11,5. However, if consideration of acid/alkaline reserve suggests the substance may not be corrosive despite the low or high pH value, this needs to be confirmed by other data, preferably by data from an appropriate validated in vitro test. U.K.

3.2.2.2.6. In some cases, sufficient information may be available from structurally related substances to make classification decisions. U.K.

3.2.2.2.7. The tiered approach provides guidance on how to organize existing information on a substance and to make a weight of evidence decision about hazard assessment and hazard classification. U.K.

Although information might be gained from the evaluation of single parameters within a tier (see Section 3.2.2.2.1.), consideration shall be given to the totality of existing information and making an overall weight of evidence determination. This is especially true when there is conflict in information available on some parameters.

3.2.3. Classification criteria for mixtures U.K.

3.2.3.1. Classification of mixtures when data are available for the complete mixture U.K.

3.2.3.1.1. The mixture shall be classified using the criteria for substances, taking into account the tiered approach to evaluate data for this hazard class. U.K.

3.2.3.1.2. When considering testing of the mixture, classifiers are encouraged to use a tiered weight of evidence approach as included in the criteria for classification of substances for skin corrosion and irritation (Sections 3.2.1.2 and 3.2.2.2), to help ensure an accurate classification as well as to avoid unnecessary animal testing. 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. However, if consideration of acid/alkaline reserve suggests the mixture may not be corrosive despite the low or high pH value, this needs to be confirmed by other data, preferably by data from an appropriate validated in vitro test. U.K.

3.2.3.2. Classification of mixtures when data are not available for the complete mixture: bridging principles U.K.

3.2.3.2.1. Where the mixture itself has not been tested to determine its skin corrosion/irritation potential, but there are sufficient data on the individual ingredients and similar tested mixtures to adequately characterise the hazards of the mixture, these data shall be used in accordance with the bridging rules set out in Section 1.1.3. U.K.

3.2.3.3. Classification of mixtures when data are available for all ingredients or only for some ingredients of the mixture U.K.

3.2.3.3.1. In order to make use of all available data for purposes of classifying the skin corrosion/irritation hazards of mixtures, the following assumption has been made and is applied where appropriate in the tiered approach: U.K.

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.

3.2.3.3.2. In general, the approach to classification of mixtures as corrosive or irritant to skin when data are available on the ingredients, but not on the mixture as a whole, is based on the theory of additivity, such that each skin corrosive or skin irritant ingredient contributes to the overall skin corrosive or skin irritant properties of the mixture in proportion to its potency and concentration. A weighting factor of 10 is used for skin corrosive ingredients when they are present at a concentration below the generic concentration limit for classification with Category 1, but are at a concentration that will contribute to the classification of the mixture as skin irritant. The mixture is classified as corrosive or irritant to skin when the sum of the concentrations of such ingredients exceeds a concentration limit. U.K.

3.2.3.3.3. Table 3.2.3 provides the generic concentration limits to be used to determine if the mixture is considered to be corrosive or irritant to the skin. U.K.

3.2.3.3.4.1. Particular care must be taken when classifying certain types of mixtures containing substances such as acids and bases, inorganic salts, aldehydes, phenols, and surfactants. The approach explained in Sections 3.2.3.3.1 and 3.2.3.3.2 may not be applicable given that many such substances are corrosive or irritant to the skin at concentrations < 1 %. U.K.

3.2.3.3.4.2. For mixtures containing strong acids or bases the pH shall be used as a classification criterion (see Section 3.2.3.1.2) since pH is a better indicator of skin corrosion than the concentration limits in Table 3.2.3. U.K.

3.2.3.3.4.3. A mixture containing ingredients that are corrosive or irritant to the skin and that cannot be classified on the basis of the additivity approach (Table 3.2.3), due to chemical characteristics that make this approach unworkable, shall be classified as Skin Corrosion Category 1 if it contains ≥ 1 % of an ingredient classified as Skin Corrosion or as Skin Irritation (Category 2) when it contains ≥ 3 % of an skin irritant ingredient. Classification of mixtures with ingredients for which the approach in Table 3.2.3 does not apply is summarised in Table 3.2.4. U.K.

3.2.3.3.5. On occasion, reliable data may show that the skin corrosion/irritation hazard of an ingredient will not be evident when present at a level at or above the generic concentration limits mentioned in Tables 3.2.3 and 3.2.4 in Section 3.2.3.3.6. In these cases the mixture shall be classified according to that data (see also Articles 10 and 11). On other occasions, when it is expected that the skin corrosion/irritation hazard of an ingredient is not evident when present at a level at or above the generic concentration limits mentioned in Tables 3.2.3 and 3.2.4, testing of the mixture shall be considered. In those cases the tiered weight of evidence approach shall be applied, as described in Section 3.2.2.2. U.K.

3.2.3.3.6. If there are data showing that (an) ingredient(s) is/are corrosive or irritant to skin at a concentration of < 1 % (skin corrosive) or < 3 % (skin irritant), the mixture shall be classified accordingly. U.K.

Table 3.2.3

Generic concentration limits of ingredients classified as skin corrosion (Category 1, 1A, 1B or 1C)/skin irritation (Category 2) that trigger classification of the mixture as skin corrosion/skin irritation where the additivity approach applies

Sum of ingredients classified as:	Concentration triggering classification of a mixture as:
	Skin corrosion	Skin irritation
	Category 1 (see note below)	Category 2
Skin corrosion Sub-Category 1A, 1B, 1C or Category 1	≥ 5 %	≥ 1 % but < 5 %
Skin irritation Category 2		≥ 10 %
(10 × Skin corrosion Sub-Category 1A, 1B, 1C or Category 1) + Skin irritation Category 2		≥ 10 %

Note: U.K.

The sum of all ingredients of a mixture classified as Skin Corrosion Sub-Category 1A, 1B, or 1C respectively, shall each be ≥ 5 % in order to classify the mixture as either Skin Corrosion Sub-Category 1A, 1B or 1C. If the sum of the ingredients classified as Skin Corrosion Sub-Category 1A is < 5 % but the sum of ingredients classified as Skin Corrosion Sub-Category 1A + 1B is ≥ 5 %, the mixture shall be classified as Skin Corrosion Sub-Category 1B. Similarly, if the sum of ingredients classified as Skin Corrosion Sub-Category 1A + 1B ingredients is < 5 % but the sum of ingredients classified as Sub-Category 1A + 1B + 1C is ≥ 5 % the mixture shall be classified as Skin Corrosion Sub-Category 1C. Where at least one relevant ingredient in a mixture is classified as Category 1 without sub-categorisation, the mixture shall be classified as Category 1 without sub-categorisation if the sum of all ingredients corrosive to skin is ≥ 5 %.

Table 3.2.4

Generic concentration limits of ingredients that trigger classification of the mixture as skin corrosion/skin irritation, where the additivity approach does not apply

Ingredient:	Concentration:	Mixture classified as:
Acid with pH ≤ 2	≥ 1 %	Skin corrosion Category 1
Base with pH ≥ 11,5	≥ 1 %	Skin corrosion Category 1
Other skin corrosive (Sub-Categories 1A, 1B, 1C or Category 1) ingredients	≥ 1 %	Skin corrosion Category 1
Other skin irritant (Category 2) ingredients, including acids and bases	≥ 3 %	Skin irritation Category 2

3.2.4. Hazard Communication U.K.

3.2.4.1. Label elements shall be used for substances or mixtures meeting the criteria for classification in this hazard class in accordance with Table 3.2.5. U.K.

Table 3.2.5

Label elements for skin corrosion/irritation

Classification	Sub-Categories 1A/1B/1C and Category 1	Category 2
GHS Pictograms
Signal Word	Danger	Warning
Hazard Statement	H314: Causes severe skin burns and eye damage	H315: Causes skin irritation
Precautionary Statement Prevention	P260 P264 P280	P264 P280
Precautionary Statement Response	P301 + P330 + P331 P303 + P361 + P353 P363 P304 + P340 P310 P321 P305 + P351 + P338	P302 + P352 P321 P332 + P313 P362 + P364
Precautionary Statement Storage	P405
Precautionary Statement Disposal	P501	]

Textual Amendments

F1 Substituted by Commission Regulation (EU) 2016/918 of 19 May 2016 amending, for the purposes of its adaptation to technical and scientific progress, Regulation (EC) No 1272/2008 of the European Parliament and of the Council on classification, labelling and packaging of substances and mixtures (Text with EEA relevance).