There are different laws throughout the world on how to identify the hazardous properties of chemicals, this is known as ‘classification’, they also cover how information about these hazards is then passed to users (through labels and safety data sheets for workers).
This can be confusing because the same chemical can have different hazard descriptions in different countries. For example, a chemical could be labelled as ‘toxic’ in one country but not in another. This confusion also acts as a barrier to international trade.
The Earth Summit held in Rio de Janeiro in 1992 and the World Summit held in Johannesburg in 2002 recognised this as an important global issue.
Given the expanding international market in chemical substances and mixtures, to help protect people and the environment, and to facilitate trade, the United Nations has therefore developed a ‘Globally Harmonised System’ (GHS) on classification and labelling.
The GHS is a single worldwide system for classifying and communicating the hazardous properties of industrial and consumer chemicals. GHS sits alongside the UN ‘Transport of Dangerous Goods’ system.
The UN brought together experts from different countries to create the GHS with the aim to have, worldwide, the same criteria for classifying chemicals according to their health, environmental and physical hazards; and hazard communication requirements for labelling and safety data sheets.
The UN GHS is not a formal treaty, but instead is a non-legally binding international agreement. Therefore countries (or trading blocs) must create local or national legislation to implement the GHS.
The UN GHS aims to ensure that information on the hazardous properties of chemicals is available throughout the world in order to enhance the protection of human health and the environment during the handling, transport and use of chemicals. GHS also provides the basis for harmonising regulations on chemicals at national, regional and worldwide level. This is important for facilitating trade. At a more basic level, GHS also aims to provide a structure for countries that do not yet have a classification and labelling system.
The UN anticipates that once fully implemented, the GHS will:
- Enhance the protection of human health and the environment by providing a system for hazard communication that is comprehensible throughout the world
- Provide a recognised framework for those countries without an existing system
- Reduce the need for testing and evaluation of chemicals
- Facilitate trade in chemicals whose hazards have been properly assessed and identified on an international basis.
The UN work programmes continue to develop and refine the UN GHS. In the long run, GHS and CLP should make classification of mixtures easier, cheaper, more accurate, and allow for more flexibility on the part of the classifier.