Nitrosamines - from problem to challenge
dr. D.B. Seeberger, Akzo Chemicals GmbH
dr. W.F. Verhelst, Akzo Chemicals BV
A review will be given of the latest regulations on nitrosamines (NA's) in the workplace atmosphere. Their potential impact on production and handling of rubber goods will be discussed.
It is important to know which chemical additives might produce toxic NA's and -which might not. A theoretical model allowing such distinction will be elucidated. This model is based on the quantum-chemical approximation of the stability of intermediate carbenium-ions. Practical examples, including measurements on rubber compounds, supporting the model will be given.
Various analytical methode are currently in use to quantitatively determine NA's at very low concentrations in rubber or the atmosphere. These will be reviewed and a preferred analytical method will be described.
Several existing chemicals would need replacement by less toxic alternatives in order to cope with most stringent regulations. Some new chemicais have recently been mentioned in this respect. Examples of the application in rubber compounding of these new chemicals, including the new thiuram Perkacit TBzTD, will be given.