PARENT SESSION

4E - Food Safety
Hall 9
8:30 AM - 10:15 AM, Thursday, 1 May 2003
Chair: Van Hemmen, J.¹, ¹
Co-chair: Trapp, S.², ²

(TH9/2) A system for the assessment of uptake of contaminants by fruits and vegetables from contaminated soils.

Rasmussen, Dorte¹, Samsøe-Petersen, Lise¹, Trapp, Stefan², ¹ DHI Water & Environment,, Dept. of Ecotoxicology, Horsholm, Denmark, Denmark² Technical University of Denmark, Environment & Resources, Lyngby, Denmark, Denmark

ABSTRACT- Exposure of humans to contaminants via consumption of home-grown vegetables and fruits from polluted soils may constitute a potential health risk. In a project financed by the Danish EPA, a set of plant-specific chemical uptake models was reviewed, developed and tested. Only models for non-ionic compounds were included. Together with models for estimating the transport of contaminants in the soil-air system and databases for plant, contaminant and soil properties, these plant-specific uptake models were compiled in a simple modelling system in Excel. Examples will be given on the usage of the modelling system: 1)The estimation of the concentration to be expected in crops grown in a polluted soil both with and without a layer of clean soil. It will be demonstrated that chemicals will still be taken up by the crops even with a layer of a clean soil, but also that the uptake is reduced. Furthermore, it will be demonstrated that the relative importance of a clean layer on the plant uptake depends on the type of plant 2)The influence of peeling the potatoe or carrot on the average concentration in the crop. It will be demonstrated that, for mobile chemicals as e.g.MTBE, the influence of peeling the vegetable is of minor importance, whereas it is of significant importance for the more immobile substances such as BaP. 3)Comparison of the expected daily intake of the pollutants via the crops with acceptable daily intakes of pollutants 4)Identification of the most critical crops with respect to the human intake of pollutants. It will be demonstrated that the daily intake of the crop and the presence of a clean soil layer are decisive factors in the identification process.

Key words: fruits , fod safety, contaminants, risk assessment