TABLE OF CONTENTS Many chemicals have the potential to damage the environment. Particular examples are those chemicals which are produced because of their biological activity, such as pharmaceuticals, pesticides, herbicides, fertilizers, and hormones.
It is often difficult to define the extent of damage which will be caused by postulated specific escapes, such as X tonnes of material M in the event of a fire and the material being washed to the drainage system by firewater.
A preferable approach is to define a quantity of material which could be expected to have an unacceptable effect on the environment (including the drainage system in some cases, such as where effluent is treated biologically before release), then to examine routes by which that quantity could escape. This avoids continuing debate about the area in the environment which would be affected, the nature of the effect (e.g., plants, microorganisms, effects on the food chain) and the duration of the effect.
Assessment of the extent, nature, and duration of the environmental effect of various chemicals is a specialist task requiring a good understanding of the specific local environment and estimation, possibly with some calculation as an aid. This is beyond the scope of this text.
