The World Health Organisation (WHO) promotes a tool called total diet studies (TDS) to measure consumer exposure to a range of chemical contaminants, from acrylamide to mercury.
The TDS consists of buying common consumer retail foods, processing them as for consumption, often combining the foods into food composites or aggregates, homogenising them, and analysing the compound for toxic chemicals and certain nutrients.
The studies are designed to measure the average amount of each chemical ingested by different age/sex groups living in a country.
Once the data collection is complete, scientists assess whether or not specific chemicals pose a risk to health.
But critics of the studies say the costs are prohibitive for developing countries, requiring sensitive measurement instruments, but WHO claims many countries, "do not need to establish sensitive analytical capabilities for all chemicals of interest."
In fact, total diet studies can be used as a priority-setting tool to enable risk managers to focus their limited resources on those chemicals, both contaminants and nutrients, that pose the greatest risks to public health, adds the UN-backed group.
The cost of conducting a baseline total diet study is estimated at about $125 000 (€101,000), if a country already has basic information on food consumption.
"Such an expense should be weighed against the possible health and economic benefits that can accrue," says WHO.
The group quotes an example of a developed country, where a study of the economic impact of Parkinson's disease, hypothyroidism, diabetes, nervous system and IQ effects suggested the negative impact of exposure to toxic chemicals in the diet ran into $800 (€652) every year for every man, woman and child.
An annual cost that does not include trade losses when contamination incidents are discovered.
"Yet, this cost to countries' economies can be reduced by lowering exposure to toxic chemicals and by optimising nutritional balances," says WHO.
On the other hand, the negative economic impact can be expected to increase with any reductions in relevant research and monitoring activities.
Examples of priority contaminants for TDS are: pesticides (such as aldrin/dieldrin, DDT (complex)and dithiocarbamates), heavy metals (cadmium, lead mercury), industrial chemicals (polychlorinated biphenyls and dioxins ), mycotoxins (aflatoxins, patulin and ochratoxin A), finally the byproduct of cooking process, acrylamide.