Towards integrated environmental quality objectives for several volatile compounds

Abstract

In the present report values are derived which can be used to set integrated environmental quality objectives (limit and target values) for 46 volatile compounds. First, Maximum Permissible Concentrations (MPCs) and Neglibible Concentrations (NCs) are derived for air, water, sediment and soil based on (eco)toxicological data. Thereafter these MPCs, NCs (limit and target values) are harmonized. Reason for harmonization is that the concentrations at e.g. MPC level in a compartment may not lead to exceeding of the MPC in other compartments. MPCs and NCs for water, sediment and soil are harmonized uzing the equilibrium partitioning method. For harmonization of the values for water, sediment and soil with the ones for air a procedure had to be developed. Since air may not be at or even near equilibrium with water, sediment and soil due to the rapid refreshment of the atmosphere a procedure is used applying computed steady state concentration ratios instead of equilibrium partitioning. The multimedia model SimpleBox is used for these computations. By comparing computed steady state concentrations with the derived MPCs and NCs based on (eco)toxicological data it is investigated whether adjustment of the MPCs or NCs for water for 5 compounds had to be adjusted downwards.<br>