Chemical labelling and classification in Europe
Classification and labelling is an important way to ensure a correct use of chemicals and alert for any potential hazards that may be associated with this use. Globalization is leading to an increase in the circulation of chemicals from different parts of the world. Most countries have their own system for classification and labelling chemicals and Material Safety Data Sheet (MSDS), whereby it is important to be aware of the legislation and criteria used. Within the European Union exist two directives for this purpose, incorporated and implemented at each national legislation (Dangerous Substances Directive (DSD) 67/548/EEC and the Preparations Directive 99/45/EC and their amendments).
Classification, labelling and packaging of Dangerous substances supplied to or within the European Union that are not regulated by other product-specific legislation are covered by the Dangerous Substances Directive 67/548/EEC.
4.1 Risk and Safety phrases
Risk phrases (or R-phrases) are used to describe a hazard while safety phrases (or S-phrases) concern the precautions to be taken in order to avoid exposure to a hazardous chemical and the measures to take in case of exposure. Both phrases are assigned to a substance in accordance with the CHIP Regulations to promote a uniform standard of labelling for users.
When considering combinations, if two phrases are written as R45-23 this means that both phrases are relevant and do not refer to all the phrases between them. Equally, if risk phrases are written together in the manner R20/R21, this means that phrases were combined into a single statement (R20/21 Harmful by inhalation and in contact with skin).
4.2 Categories of Danger and Hazardous Symbols
A substance is considered to be dangerous, and hence regulated by DSD 67/548/EEC, if it is classified in any of the categories shown in Table 2. The classification process involves the identification of the hazard based on the criteria defined in the DSD, followed by the assignment of applicable risk phrase(s) and hazard symbols. It is important to note that classification is based on the intrinsic hazardous properties of the chemical substance and not on the probability of hazardous use. Hence, classification cannot be removed or replaced by the supplier based on the intended use of the chemical that would be such that the probability of danger is anticipated as insignificant. The user should take care not to confuse "hazard" and "risk". Hazardous symbols are illustrated in figure 2 and described below.
Table 2. Categories of danger for chemical substances (Council Directive 67/548/EEC)
| CATEGORY OF DANGER | INDICATION OF DANGER | SYMBOL LETTER |
| Health related | ||
| Very toxic | Very toxic | T+ |
| Toxic | Toxic | T |
| Harmful | Harmful | Xn |
| Corrosive | Corrosive | C |
| Irritant | Irritant | Xi |
| Sensitising | Harmful | Xn |
| Irritant | Xi | |
| Carcinogenic: | ||
| Category 1 and 2 | Toxic | T |
| Category 3 | Harmful | Xn |
| Mutagenic: | ||
| Category 1 and 2 | Toxic | T |
| Category 3 | Harmful | Xn |
| Toxic to reproduction: | ||
| Category 1 and 2 | Toxic | T |
| Category 3 | Harmful | Xn |
| Physicochemically related | ||
| Extremely flammable | Extremely flammable | F+ |
| Highly flammable | Highly flammable | F |
| Flammable | - | - |
| Explosive | Explosive | E |
| Oxidising | Oxidising | O |
| Environmentally related | ||
| Dangerous for the environment | Danger to environment | N or/and R52, R53, R59 |
Source: http://www.fdtodd.co.uk/images/commercial/hazardous_symbols.png
Flammable
A material is considered flammable (symbol F) considering its ease at ignition either naturally or through the presence of an ignition source.
Explosive
An explosive substance (symbol E) is a chemical or mixture of chemicals that becomes unstable under certain environmental conditions, releasing its stored energy. The lower and upper explosive limits (LEL and UEL) define the range in which a gas or vapour in air is capable of igniting in the presence of an ignition source.
Corrosive
Corrosive chemicals can destroy or irreversibly damage a surface or substance with which they come into contact, including both living tissues (skin, eyes, lungs) and materials such as response equipment of oil and HNS spills.
A substance is classified as corrosive (symbol C) to living tissues if it causes full thickness destruction of the tissue in at least one animal during the test for irritancy or validated in vitro studies, as given in annex V of DSD 67/548/EEC. Even though the test is only performed on skin, it is assumed by implication that the same effects would occur if the chemical came into contact with the eyes.
For ethical reasons, substances or mixtures with a pH value of 2 or less and equal or greater than 11.5 are not required to be tested, unless the extreme pH is the basis for classification of corrosivity.
Very Toxic
Toxic or very toxic chemicals (symbol T/T+) include those that cause death or injury to living organisms if inhaled, ingested or absorbed through the skin at low levels. Toxicity is often measured and classified attending the degree of risk that a particular concentration represents to human health or the environment.
Oxidizing hazard
Substances that are not combustible but may cause or contribute to the combustion of other material are classified as oxidizing hazard substances (symbol O).
Harmful/Irritant
A harmful chemical (symbol Xn) may be dangerous to health while those with irritant properties (symbol Xi) can induce inflammation reactions to the skin (dermatitis) and mucous membranes in a live organism (eyes, throat, lungs...).
The criteria for this effect are based either on human evidences of adverse effects or positive results of appropriate animal studies. Two main tests are used to classify a substance as harmful/irritant: the adjuvant method (at least 30% of the exposed animals show a positive effect) and the non-adjuvant method (at least 15% of the exposed animals show a positive effect).
Danger to environment
This classification informs the user of the potential environmental hazards that substances pose to ecosystems (symbol N). At present time the classification criteria available are those for aquatic organisms and are established on acute observed effects in fish (LC50, 96h), daphnia (EC50, 48h) and algae (IC50, 72h). Persistence and bioaccumulation potentials (log Pow or BCF) values are also taken into consideration for some classifications.
Carcinogen, Mutagen and Toxic for reproduction
According to Annex VI of the DSD (67/548/EEC) and its amendments, carcinogen and mutagen chemicals as well as those that show toxic effects on reproduction are classified in three different categories and associated to risk phrases as shown in table 3.
Table 3. Carcinogenicity categories and corresponding risk phrases for mutagenicity and toxic substances for reproduction.
| HEALTH EFFECT | CATEGORY 1 | CATEGORY 2 | CATEGORY 3 |
| Carcinogen | |||
| Can either induce cancer or increase its incidence | T; R45 May cause cancer | T; R45 May cause cancer | Xn; R40 Limited evidence of a carcinogen effect |
| T; R49 May cause cancer by inhalation | T; R49 May cause cancer by inhalation | ||
| For substances known to cause cancer in humans | Sufficient evidence to presume also carcinogenic in humans (based on clear evidence from appropriate animal studies, or other relevant information) | Cause for concern, based on evidence from appropriate animal studies, or other relevant information, but insufficient evidence to place in Category 2. | |
| Mutagen | |||
| A substance that may either induce heritable genetic effects or increase their incidence | T; R46 May cause heritable genetic damage | T; R46 May cause heritable genetic damage | Xn; R68 Possible risks of irreversible effects |
| For substances known to be mutagenic in humans | Sufficient evidence to presume also mutagenic in humans (based on clear evidence from appropriate animal studies, or other relevant information) | Cause for concern, in humans owning to possible mutagenic effects from appropriate animal studies, but insufficient evidence to place in Category 2. However, indications of ability to induce mutations in somatic cells, also give rise to placing in this category. It is a warning for possible carcinogenic activity. | |
| Toxic to Reproduction | |||
| Substances that may impair either male or female reproductive function or cause non-inheritable harmful effects in the offspring | T: R60 May impair fertility. For substances known to impair fertility in humans. | T: R60 May impair fertility. For substances known to impair fertility in humans. | Xn; R62 Possible risk of impaired fertility. For substances that cause concern, for human fertility. |
| T; R61 May cause harm to the unborn child. | T; R61 May cause harm to the unborn child. | Xn; R63 Possible risk of harm to the unborn. | |
| For substances known to cause developmental toxicity in humans. | For substances known to cause developmental toxicity in humans (for both, based on clear evidence from appropriate animal studies, or other relevant information). | For substances which cause concern for humans due to possible developmental toxic effects. Based on evidence from appropriate animal studies, or other relevant information. |
Source: Robinson L, Thorn I. (2005).
For more detailed information see:
Annex VI of DSD 67/548/EEC: http://ec.europa.eu/environment/archives/dansub/pdfs/annex6_en.pdf
EU-OSHA: http://oshwiki.eu/wiki/Carcinogenic,_mutagenic,_reprotoxic_(CMR)_substances
List of substances and their classification: http://www.phy.cam.ac.uk/internal_resources/hands/hazards/coshh/carcin2.pdf
List of carcinogenic substances (IARC): http://monographs.iarc.fr/ENG/Classification/ClassificationsAlphaOrder.pdf
4.3 Chemical Labelling
Products labels are a method to summarize information on chemical products and hence allow the user to be alerted on the hazard and precautions associated. The actual label is designed to provide information in the simplest and objective manner using hazard symbols, classification and usually described with appropriated risk and safety phrases, according to those of the corresponding MSDS (Figure 3).
A label should contain:
- Supplier identification (name, address and telephone number)
- Product name
- Indication of the danger
- Hazardous symbol
- Risk and safety phrases
Source: https://reliancelabel.files.wordpress.com/2013/11/gl1010forblog-3.jpg
4.4 Chemical Classification
According to the DSD, the classification criteria for chemical substances are usually based on data from specific model species or, in some cases, validated in vitro studies covered in OECD guidelines. When effects of chemical substances in humans are adequately shown to be different from those expected according to the effects described in animal test studies, classification should be based on human evidence.
Annex I of DSD 67/548/EEC contains a list of pre-classified chemical substances and assigned risk and safety phrases that must be followed. Chemical substances that are not listed in Annex I must be provisionally classified by suppliers according the guidelines given in Annex VI Part IID.
When the classification process is based on results arising from acute toxicity, repeated dose or non-lethal, irreversible effects, chemical substances must be assigned in the category of "Very toxic", "Toxic" or "Harmful", respectively. As an example, Table 4 shows details of the criteria for these three categories, obtained from results where the classification was based on acute lethal effects.
Table 4 - Criteria for chemical classification based on acute lethal effects.
| CATEGORY | ORAL, RAT (MG KG-1) |
DERMAL, RABBIT OR RAT (MG KG-1) |
INHALATION, RAT (4H MG L-1) (GASES AND VAPORS) |
| Very Toxic | LD50 ≤ 25 | LD50 ≤ 50 | LD50 ≤ 0.5 |
| Toxic | 25 < LD50 ≤ 200 | 50 < LD50 ≤ 400 | 0.5 < LD50 ≤ 2 |
| Harmful | 200 < LD50 ≤ 2000 | 400 < LD50 ≤ 2000 | 2 < LD50 ≤ 20 |
Source: Robinson L, Thorn I. (2005).
http://ec.europa.eu/environment/archives/dansub/pdfs/annex6_en.pdf
REFERENCES
Robinson L, Thorn I. (2005). Toxicology and ecotoxicology in chemical safety assessment. Blackwell Publishing Ltd., Oxford, UK. 157p.
Online resources
Agency for Toxic Substances & Disease Registry (ATSDR): http://www.atsdr.cdc.gov/substances/index.asp
Annex VI of DSD 67/548/EEC: http://ec.europa.eu/environment/archives/dansub/pdfs/annex6_en.pdf
CHIP Regulations: http://www.hse.gov.uk/chemical-classification/legal/chip-regulations.htm
Dangerous Substances Directive 67/548/EEC: https://osha.europa.eu/en/legislation/directives/58
Dangerous Substances Directive 79/831/EEC: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31979L0831:EN:HTML
Dangerous Substances Directive (79/831/EEC) Annex VI: http://ec.europa.eu/environment/archives/dansub/pdfs/annex6_en.pdf
EU-OSHA: http://oshwiki.eu/wiki/Carcinogenic,_mutagenic,_reprotoxic_(CMR)_substances
European Chemicals Agency (EChA): http://echa.europa.eu/regulations
International Tanker Owners Pollution Federation (ITOPF): http://www.itopf.com/knowledge-resources/documents-guides/document/tip-17-response-to-marine-chemical-incidents/
List of carcinogenic substances (IARC): http://monographs.iarc.fr/ENG/Classification/ClassificationsAlphaOrder.pdf
List of substances and their classification: http://www.phy.cam.ac.uk/internal_resources/hands/hazards/coshh/carcin2.pdf
Responsible care web page: http://responsiblecare.americanchemistry.com/Responsible-Care-Program-Elements/Product-Safety-Code
Risk and safety phrases (Annex II and III of DSD 67/548/EEC): http://www.msds-europe.com/id-485-r_s_phrases.html
Scientific Committee on Cosmetic Products and Non-Food Products (SCCNFP): http://ec.europa.eu/health/scientific_committees/consumer_safety/sccnfp/index_en.htm
