What is the difference between bitumen and coal tar (or tar sands)?
Bitumen and coal tar, or tar as it is commonly known, are two very different materials. Firstly, they are produced in different ways: bitumen is distilled from crude oil, using a number of different processes to produce bitumen products with special characteristics. Coal tar is made by processing coal at very high temperatures (pyrolysis). Coal tar was commonly used for road building and waterproofing up to the middle of the 20th century, but was gradually phased out and replaced by bitumen during the 1950s.
Second of all, bitumen and tar have very different characteristics. Although they are similar in appearance and in use profile, the chemical composition of coal tar is very different from bitumen, and this has a huge effect on the nature of hazard that coal tar presents to the user: coal tar is classified as carcinogenic, whereas bitumen is not. Tar sands - also known as cold oil sands or bitumen sands - contain naturally occurring heavy crude oil. This can be extracted using a number of recently-developed technical processes, and then refined just the same as crude oil extracted from a more traditional drilling process.
Should the general public be concerned about any hazards from bitumen?
No. The bitumen that is used on roads, roofs or pavements, for example, is inert and does not present any known health or environmental hazard.
Are there any safety hazards for people who work with bitumen?
Bitumen is normally manufactured, stored, transported and handled at high temperatures. The most significant hazard to workers who deal with hot bitumen is the potential to cause burns in case of splashes or spills. Bitumen is usually applied hot. Hot bitumen gives off emissions that can cause minor respiratory tract or eye irritation after prolonged, close exposure. Apart from this temporary irritation, under normal conditions there is no evidence that working with bitumen is hazardous to worker health. The risk of exposure to this hazard - and, therefore, the potential health impact on workers – is minimised through good temperature control, clearly defined working practices and appropriate protective workwear.
In May 2013, the IARC published Monograph Volume 103: “evaluation of occupational exposures to bitumen and bitumen emissions, and some N- and S-Heterocyclic Polycyclic Aromatic Hydrocarbons.” This gave the full background to IARC's evaluation published in 2011. After a detailed review of this report, the European bitumen manufacturing industry saw no need to update existing health and safety guidelines. The industry continues to review safety guidelines based on industry-wide research and health and safety expertise, to ensure these guidelines remain relevant to the latest available information.
How can workers protect themselves against exposure to emissions from bitumen?
Workers can minimise their exposure to potentially emissions by following good working practices, such as:
- Keeping the temperature of the material as low as practically possible
- Working in well ventilated conditions (including simple practices e.g. standing upwind of the source of fumes)
- Job rotation around the worksite
- Using personal protective equipment, especially in confined spaces