The first harmonised total diet study in Portugal: Planning, sample collection and sample preparation

Area of Science:

• Food safety and toxicology
• Dietary exposure assessment
• Public health nutrition

Background:

• Portugal's first Total Diet Study (TDS) was established using harmonized protocols from the TDS-Exposure project.
• Existing literature lacked detailed information on TDS planning, sample collection, and preparation methodologies.
• A comprehensive TDS is crucial for evaluating dietary exposure to contaminants.

Purpose of the Study:

• To detail the planning, sample collection, and preparation procedures for Portugal's inaugural Total Diet Study.
• To establish a foundation for accurate dietary exposure assessment in the Portuguese population.
• To enable international comparisons and trend evaluations through harmonized methodology.

Main Methods:

• A food list of 1070 items was developed for individuals aged 18-74 years, based on 24-hour dietary recall data.
• 164 Total Diet Study samples were defined using FoodEx2 classification, with 'Composite dishes' and 'Fish and Fish products' being most prevalent.
• 227 samples, comprising national, regional non-seasonal, and regional seasonal types, were collected in the Greater Lisbon region between 2014-2016.

Main Results:

• The study meticulously documented the entire process from food list creation to sample preparation.
• Sample preparation involved simulating consumption, pooling, homogenization, and storage at -18°C.
• The harmonized procedures are designed to facilitate comparative exposure assessments and trend analysis.

Conclusions:

• The detailed methodology provides a valuable resource for future Total Diet Studies in Portugal and elsewhere.
• The implemented harmonized procedures are essential for robust international comparisons of dietary exposure.
• This study lays the groundwork for ongoing monitoring of dietary exposure and potential risks.