Total diet studies: What they are and why they are important
(Monday, 6th July 2015, 09.00-10.30)
The protection of consumers from potential hazards in the food supply is one of the most important public health functions for any government. In this regard, the World Health Organization (WHO) has recognized total diet studies as the most cost-effective tool for assessing dietary exposures to a range of potentially hazardous chemicals and intakes of essential nutrients. The importance of total diet studies in assuring the safety of the food supply and identifying possible health risks will be described.
- Understand the basic differences between total diet studies and other monitoring activities
- Appreciate the unique contribution to public health afforded by total diet studies
Criteria for selection of chemical substances and population targets
(Monday, 6th July 2015, 11.00-12.30)
The lecture will be divided into three main parts. The first part concerns the selection of targeted populations for a TDS: selection criteria, presentation of the different possible population groups, and corresponding needs for the sampling plan. The second part will be a presentation about a prioritization tool for the selection of substances to be included in a TDS: selection criteria, judgments of the substances, and use of the tool. The third part will describe application of the tool.
- Populations: an overview of the population groups that can be targeted in a TDS and the corresponding methodological issues
- Chemical substances: understand and to be able to apply the prioritization method to select chemicals for a TDS
Developing a TDS food list to compose TDS samples
(Monday 6th July 2015, 14.00-15.30)
Participants will go through the multistep process of formulating a Total Diet Study (TDS) food list composed of food categories sufficiently representative for a reference diet, defining a sampling plan, and finally collecting the food products to compose the market baskets. Documentation, procedures, and tools are necessary for each of these steps and there are critical points in each. The availability of data and ancillary information are crucial. The kind of data available influences the potential to identify core foods and the alignment with dietary exposure evaluation. Information about the foods is fundamental in taking account of the variables affecting potential contamination at production (e.g. market share data for packed foods; varieties for fresh foods) or delivery (e.g. home treatment and cooking methods). Extensive white literature is available on TDS previously performed; a similarly set of technical publications is available for specific groups of substances (e.g. pesticides), and a series of reports concerning TDS carried out all over the world, especially where food composition tables are not available. TDS-Exposure has taken up the challenge of designing systems for implementing harmonised TDS studies throughout Europe, following the EFSA’s guidelines to exploit the work done in the past and create an evidence-based system for TDS.
- Understanding the component of the process to formulate a food-shopping list
- Aligning reference diet and composite food samples, the role of food description, and food coding systems
- Food categories and food products, and how to obtain representatives market basket
- Importance of ancillary information to refine the food-shopping list
- Recording data for the future use of food products information
(Monday, 6th July 2015, 16.00-18.00)
Dissemination and communication are an integral aspect of research, but the skills and understanding necessary for effective delivery are often neglected. This lecture will explore the importance and benefits of dissemination and communication, the actors involved, and the media as a partner in public empowerment.
- Understand the differences between dissemination and communication, how science is broadcast and received by different audiences, and who and why stakeholders matter
- Appreciate how different communication tools can and should used effectively
Planning a Total Diet Studies (Parts 1 and 2)
(Tuesday, 7th July 2015, 09.00-12.30)
Planning TDS is a complicated process with many sequential steps. It is important to set principal objectives, decide about management/ budget and, technically, describe the main methodological components of a study. Participants will go through the main steps in detail to appreciate how components are interrelated and the main challenges and potential limitations of TDS. Specific focus will be on principles of representative sampling in relation to the TDS food list.
1. An overview of the challenges when planning a TDS including sampling
2. Understanding importance of planning for quality
Food consumption data and their use in dietary exposure assessment to contaminants
(Tuesday 7th July 2015, 14.00-15.30)
This lecture will provide an overview of the EFSA Comprehensive European Food Consumption Database and the main principles of the dietary exposure assessment, with some illustrations based on cadmium.
- Be aware of how food consumption data are currently collected throughout Europe and collated in the EFSA Comprehensive European Food Consumption Database
- Understand the principles of dietary exposure assessment to chemicals and especially how consumption data are used as input of exposure modelling
Sample preparation and culinary operations
(Tuesday, 7th July 2015, 16.00-17.30)
A key part of TDS work is that exposure calculations are based on chemical concentrations measured in the food AS EATEN. So it is important to ensure the food preparation methods used in TDS work, properly reflect consumer practice. Depending on their chemical characteristics, food preparation methods can cause concentrations to rise, fall or remain uncharged. Food preparation methods may also introduce additional extraneous contaminants unless care is taken. There is particular interest nowadays to maximise the utility (and so spread the cost) of TDS work by using archived samples for analysis for as-yet not known (completely unknown or just not yet decided) contaminants. This re-emphasises the need not only to select the correct preparation procedures but, as crucially, to keep extensive records so that the relevance of the food preparation methods used can be evaluated later on.
- Why and how culinary operations must mimic normal consumer behaviour in the country and/or region and/or population of interest
- How to prepare samples for analysis and/or archive in a reliable and traceable way
Food collection for TDS – Sampling plan
(Wednesday, 8th July 2015, 09.00-10.30)
Collection of foods for TDS is a process based on the prepared sampling plan. This is the next step after designing of the TDS food list followed by suggesting of TDS pooled samples. TDS sample plan must take into account many additional factors including number of TDS samples, number of subsamples in the pool, selection of individual food items/brands, national/regional character of food items, seasonality in consumption, type of culinary treatment. Practicalities including throughput of food collection, transportation, storage and kitchen preparations of foods are also very important for good sampling in TDS. Participants will gain an understanding of how to keep a balance between requests and practical possibilities. A part of lecture will be dedicated also to practical experience obtained in on-going pilot study.
- Be aware of sampling plan as an essential basis for food collection in TDS and understanding its components
- Understanding the main steps in the process of food collection and its relations to other parts of TDS
Analytical measurements: what’s behind the numbers
(Wednesday, 8th July 2015, 11.00-12.30)
Measurement data are often perceived as the absolute truth. Once out of the analytical environment, they often start to life of their own and the numbers are stripped of all meta-data. This, however, can have severe consequences towards data treatment and interpretation at a later stage. In order to assess the value of a number, it helps if the assessor has insight in how the numbers came about. After an introduction on how samples are actually analysed, it will become clear how data re generated from of a food sample. The main part of the lecture will be quality of data. The origin and background of measurement uncertainty will be discussed to reveal what is behind the numbers.
- Gain insight into the process of generating measurement data (speed-course analytical technology)
- Learn about measurement uncertainty: there is more to a number than just the digits
Systems for describing food – LanguaL/FoodEx
(Wednesday, 8th July 2015, 14.00-18.00)
These lecture and practical session will provide an overview of systems for detailed description of food including LanguaL and the EFSA FoodEX food list combined with facet descriptors.
- Become familiar with the Langual multi-faceted system for food description and EFSA FoodEx2 foodlist and associated facet descriptors
- Identify differences between the systems and their strengths and weaknesses
FoodCASE-Risk in the context of food data
(Thursday, 9th July 2015, 09.00-10.30)
The lecture will present a ‘big picture’ view of food data and where TDS data is located in this landscape as well as details on how to import, manage and export TDS data in FoodCASE-Risk.
- See one possible abstraction of a TDS in a software system
- Learn how TDS data can be used in combination with other food data
Quality Management Principles and Practices suited to TDS
(Thursday 9th July 2015, 11.00-12.30 and 14.00-15.30)
Lectures will focus on quality concepts required for TDS process. Initially, a brief overview of quality tools will be presented. The key concepts that support TDS generic flowchart will be introduced. Documentation and identification of mandatory and recommended requirements will also be outlined.
- Gain insight of quality practices and principles in place at TDS projects
- Evaluate the advantages and limitations of quality managements practices implemented in TDS beneficiaries
Exposure assessment at the international level
(Friday 10th July 09.00-12.30 including practical)
Exposure assessment needs input data from consumption surveys and concentration data from either monitoring programmes or from Total Diet Studies. Monitoring programs are often biased towards targeted sampling. TDS concentration data are assumed to be more representative, but the quality of TDS data is also influenced by uncertainties. In this lecture, we will highlight different exposure models and the relevance of good input data for an optimal exposure assessment.
- Understand different exposure models and the relevance of good input data for TDS