Highly reactive compounds


Reactive toxicity encompasses important endpoints such as skin and respiratory sensitisation, hepatotoxicity, genotoxicity and elevated acute aquatic toxicity. Others may cause cancer and/or may affect reproduction.

These adverse effects are initiated by, among others, electrophilic chemicals and those transformed into electrophiles.


Function and use

Highly reactive compounds do not occur naturally and tend to react easily with many other compounds in our bodies and in the environment. The highly reactive compounds may be used in polymer production or in chemical manufacturing because of their intrinsic reactive properties.


Areas of application

One compound in this group, formaldehyde, is used as a biocide (against mildew and moth) and as a solvent.

It is also used in urea-formaldehyde resins giving several “easy-care” properties in textiles, e.g. permanent press / durable press, anti-cling, anti-static, anti-wrinkle, anti-shrink (especially shrink-proof wool), waterproofing, stain resistance (especially for suede and chamois), perspiration proofing, and colourfastness.

Formaldehyde is also used in jackets and coats and in upholstery to confer structural and flame-retardant properties, respectively. Furthermore, it is used as glue in particleboards and other wood-based panels.

Another compound, acrylamide is primarily used in polymer production.



Most of the compounds in this group are restricted in REACH annex XVII due to CMR classifications and some are included in the REACH Candidate List.

Formaldehyde release from woodchip boards is specifically restricted in many EU member states by a release limit.



Alternative substances

In chemical synthesis, less toxic alternatives should always be considered. Especially in scaled-up applications, less hazardous chemicals need to be evaluated. For formaldehyde, there are alternatives in various applications. An alternatives assessment study for formaldehyde can be found here.

Examples of alternatives to highly reactive compounds are:





Chemical name



Polymaleic acid