: Muhle, H.

Abstract
Introduction: The group of particles to be covered under this section includes materials which are poorly soluble. The reason for creating a joint group for these materials is that in toxicology usually the dissolved, bioavailable molecules or ions causes toxic effects. Poorly soluble materials act in a different way on the body; it is the entire particle which interact with cells. However, exceptions to this concept are, e.g. quartz and mineral fibres, which show an intrinsic toxicity. In this chapter, the group of poorly soluble particles will be considered together.