R L Thompson

Publications (2)4.26 Total impact

• Article: Validation analysis of probabilistic models of dietary exposure to food additives.

  M B Gilsenan, R L Thompson, J Lambe, M J Gibney
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  ABSTRACT: The validity of a range of simple conceptual models designed specifically for the estimation of food additive intakes using probabilistic analysis was assessed. Modelled intake estimates that fell below traditional conservative point estimates of intake and above 'true' additive intakes (calculated from a reference database at brand level) were considered to be in a valid region. Models were developed for 10 food additives by combining food intake data, the probability of an additive being present in a food group and additive concentration data. Food intake and additive concentration data were entered as raw data or as a lognormal distribution, and the probability of an additive being present was entered based on the per cent brands or the per cent eating occasions within a food group that contained an additive. Since the three model components assumed two possible modes of input, the validity of eight (2(3)) model combinations was assessed. All model inputs were derived from the reference database. An iterative approach was employed in which the validity of individual model components was assessed first, followed by validation of full conceptual models. While the distribution of intake estimates from models fell below conservative intakes, which assume that the additive is present at maximum permitted levels (MPLs) in all foods in which it is permitted, intake estimates were not consistently above 'true' intakes. These analyses indicate the need for more complex models for the estimation of food additive intakes using probabilistic analysis. Such models should incorporate information on market share and/or brand loyalty.
  Food Additives and Contaminants 11/2003; 20 Suppl 1:S61-72. · 2.13 Impact Factor
• Article: Development of databases for use in validation studies of probabilistic models of dietary exposure to food chemicals and nutrients.

  C Leclercq, D Arcella, A Armentia, P E Boon, A G Kruizinga, M B Gilsenan, R L Thompson
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  ABSTRACT: The data currently available in the European Union in terms of food consumption and of food chemical and nutrient concentration data present many limitations when used for estimating intake. The most refined techniques currently available were used within the European Union FP5 Monte Carlo project to estimate, as accurately as possible, the intake of food additives, pesticide residues and nutrients. Databases of 'true' intakes of food additives (based on brand level food consumption records and additive concentration data), pesticide residues (based on duplicate diet studies) and nutrients (based on biomarker studies) have thus been generated. These kind of estimates are rarely repeatable because the databases generated and used to calculate them require an extraordinary expenditure of time and resources. The databases created served the purpose of estimating as accurately as possible 'true' chemical intakes for assessing the validity of additive, nutrient and pesticide probabilistic models.
  Food Additives and Contaminants 11/2003; 20 Suppl 1:S27-35. · 2.13 Impact Factor