|
When conducting internal risk characterizations, products are categorized as high, medium or low risk based on aquatic toxicity and biodegradation data as well as the intended use and volume data. Akzo Nobel and its predecessor companies have been manufacturing and distributing surfactants for more than 50 years. Surfactants are used in all types of applications. The levels at which surfactants are used in the final products vary from very low levels to very high levels depending on the specific application.
In standard laboratory tests, surfactants are often classified as hazardous to aquatic species. Since surfactants stick to hard surfaces, in laboratory studies, using sterile laboratory conditions, surfactants tend to also adhere to the breathing structures of aquatic species resulting in toxicity to the test species.
The environment in laboratory tests however is not representative of natural environments where numerous factors exist to mitigate the hazards. For example in natural environments surfactants bind to organic particulate matter and also often rapidly degrade. This reduces the bioavailability and hence, the aquatic toxicity of the chemicals.
The other side of the risk equation is the exposure to the chemicals. The use of the surfactant in the particular application is categorized by predicted environmental release and the volume sold into that application.
This is the basis of the internal screening level characterizations that are conducted. For the chemicals we manufacture and distribute, we evaluate the aquatic toxicity hazard data and the degree of biodegradation and multiply by a factor that represents an expected exposure.
Based on all of the factors that we consider, a range of values for each product (depending on uses) and across the products is generated. Higher risk materials could be candidates for risk management actions.
|
