GIS Based Chemical Fate Modeling: Principles and Applications

Chapter 21

Perspectives: The Challenge of Cumulative Impacts and Planetary Boundaries

Until the very recent past, chemical fate and transport modeling focused on understanding the environmental behavior of a limited number of molecules, for which a harmful potential effect had been demonstrated. These can be studied and managed (i.e., restricted or banned) one by one, for example, within international conventions such as the Stockholm convention on persistent organic pollutants (POPs; www.pops.int), as well as national legislation.

However, the future calls for different types of applications: we will have to address a multitude of chemicals, an order of magnitude of 10⁵ types of molecules released to the environment from human activities, and their combined action on human health and ecosystems. The complex mixtures of chemicals potentially affecting ecosystems change in time following technological evolution, the market, and industrial conditions. Many of the very high number of synthetic chemicals used globally are ubiquitous in ecosystems, although in highly variable concentrations and with different phase partitioning, yielding a wide range of ecological and human health effects; the understanding of their environmental fate is often very limited. While only a very small set of synthetic chemicals is regularly monitored in the world, and even less chemicals have environmental concentration limits already established, researchers continuously identify emerging pollutants for ...