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Understanding CAS registration numbers

08-08-2024
3 min

A guide to CAS registration numbers

Did you know that each chemical substance has a unique identifier known as a CAS registration number? It’s a bit like a license plate. This number is crucial for ensuring safety, compliance, and consistency in the chemical industry. In this blog, we'll explore what a CAS registration number is, its significance, and how it's used across various sectors. Keep reading to get a full understanding of this essential tool.

What is a CAS registration number?

A CAS registration number, often abbreviated as CASRN or CAS Number, is a unique numerical identifier assigned to every chemical substance described in the scientific literature. CAS stands for Chemical Abstracts Service, a division of the American Chemical Society, which is responsible for assigning these numbers to provide a consistent way to identify chemicals and their associated data.

A CAS number is generally formatted as a series of up to 10 digits divided into three parts by hyphens, like this: XXXXXX-XX-X. The rightmost digit is a check digit used to verify the validity of the number, the middle part can have two or more digits, and the leftmost part (which can be the longest) increases as new substances are registered.

Importance of CAS registration numbers

Standardisation

CAS numbers provide a standard method for identifying chemical substances. This standardisation ensures that each substance is uniquely identified, which is crucial for research, commerce, and regulatory purposes.

Global recognition

CAS numbers are internationally recognised and used. This global recognition facilitates the exchange of information and materials between scientists, manufacturers, and regulatory bodies across different countries.

Safety and regulation

In the context of safety data sheets and regulatory compliance, CAS numbers help in the accurate identification of substances. This ensures that all relevant safety and handling information is correctly applied.

Practical applications of CAS numbers

Researchers use CAS numbers to quickly find specific chemical information, making it easier to retrieve data from scientific literature and databases. In industries like pharmaceuticals, agriculture, and manufacturing, CAS numbers help order, label, and manage chemicals, ensuring the right substances are used and tracked properly.

Plus, CAS numbers simplify the global trade of chemicals by providing a common language everyone can understand, which reduces errors and improves safety and compliance.

How does this work for ethanol?

Identification and standardisation

In the alcohol industry, you'll often hear different names for the same thing, like ethanol, ethyl alcohol, and grain alcohol. They all refer to the same substance that's used in everything from drinks and medicines to fuel. 

 

The CAS number 64-17-5 uniquely identifies ethanol, ensuring that there is no confusion with other substances. This is particularly important given ethanol's widespread use and the need for precise formulation in products.

Safety and compliance

Ethanol's CAS number is crucial for safety data sheets and regulatory compliance. It provides an easy reference for all relevant safety information, handling instructions, and regulatory standards. 

 

This helps manufacturers and users to follow legal requirements and maintain safety in the workplace.

Industry applications

In the pharmaceutical industry, ethanol is used as a solvent and in the formulation of various medications. The CAS number ensures that the correct type of ethanol is used, maintaining the efficacy and safety of pharmaceutical products.

 

In the personal care industry, the CAS number helps verify the purity and concentration of ethanol in hand sanitisers and perfumes, guaranteeing product quality and consumer safety. The CAS registration also facilitates the trade and quality control of ethanol as a renewable fuel source, ensuring that it meets the necessary specifications in the biofuel industry

Conclusion

CAS registration numbers are a fundamental tool in the chemical industry, providing a standardised, globally recognised system for identifying substances. These numbers are used worldwide by researchers, industry professionals, and regulatory bodies to unambiguously identify substances without the confusion of multiple names and synonyms.

They enhance safety, quality control, and efficiency in various applications, from research to industry.