Abstract

Rare earth metals (RE) are not produced in the Netherlands. However, the Netherlands import approximately 10% of the world production of RE ; most manufactured products are exported. Important applications are in catalysts, glass/ceramics, lighting and electronics. Based on available information catalyst industry and artificial fertilizer industry seem to be the most important sources of emissions. Available information on both exposure and (no) effect levels for humans and ecosystems are poor, both qualitatively and quantitatively. Based on margins of safety, one may conclude that inhalatory exposure does not present a risk to the general population in the Netherlands, but there is insufficient information to indicate the risks related to oral exposure. In this respect it is recommended to evaluate the influence of RE containing artificial fertilizers on the RE concentrations in soil and agricultural consumption products. Based on very limited information on the ecotoxicological characteristics of RE, an indicative maximum tolerable risk concentration (MTR) for RE of 0.1 - 1 mug.1-1 per "dissolved" element was derived for surface water. This conservative range of the MTR estimate overlaps the range of maximum concentrations that may be expected to occur in the field. Taking into account the uncertainty in risk estimation it is recommended to initiate both in depths studies on effects and exposure.