State of the art on Total Diet Studies based on the replies to the EFSA/FAO/WHO questionnaire on national total diet study approaches
Total Diet Studies (TDS) were recognised as a cost-effective approach to estimating dietary exposures of contaminants by the World Health Organization (WHO) in 1978. By 2011 approximately 33 countries in the world had been engaged in the process of performing a TDS. A Working Group of experts on TDSs conducted a survey aimed at mapping the methodological aspects of the latest TDSs conducted in the world and also investigating the overall readiness of countries with no previous TDS experience to conduct the survey in the future. The survey results showed differences in TDS implementation around the world. The main differences were reported in the principles for compiling a food list, the representativeness of the sampling plan (regions, seasons), the strategy for pooling foods prior to analysis and quality requirements set for the laboratories involved in the food analysis. Countries with no previous experience reported interest in the TDS study approach and possible plans to carry out a TDS in the future. The interest to carry out a TDS was, however, related with the need for further guidance and training in this area and allocation of funding. The results of the survey confirmed the need for harmonisation of the TDS methodology at international level.