In this module we would like to introduce three case studies to you.

The first case study discusses dietary exposure of consumers to captan and tolylfluanid residues. It identifies what the levels of dietary exposure are and which food commodities contribute the most to this exposure.

The risk assessment look at the risk for consumers of choleragenic Vibrio cholera O1 and O139 in warm-water shrimp in international trade. It therefore explicitly looks at the risks associated with imported shrimps.

This case study looks at the risks associated with the consumption of imported Roquefort cheese. Following the determination of the level of risk, the case study describes which risk management measures can be taken to reduce the risk associated with imported Roquefort cheese.

This risk assessment focused exclusively on the exposure assessment.

The objectives were to:

1. Calculate the acute dietary exposure to captan and tolylfluanid in five European countries, expressed in μg/kg bodyweight/day.
2. Determine the food commodities that contribute most to dietary exposure.

Data on national consumption were collected through different data collection systems in the five countries.

Data on pesticide residues were obtained from national pesticide monitoring programs. A challenge was that countries did not use the same threshold concentration for reporting positive samples.

A sample with a certain concentration of pesticides could therefore be reported as positive in one country and as negative/non-reported in another country.

Processing of raw commodities may change the pesticides concentration in the final commodities – often reducing the concentrations.

Results from a previous study were used to determine this processing factor.

The acute dietary exposure to captan and tolylfluanid differed between countries depending on the dietary habits of the population and the prevalence of contaminated raw products.

Depending on the dietary habits, different raw commodities contributed most to dietary exposure.

However, fruits were important sources of captan and tolylfluanid exposure all countries.

This case study was done in the Europe. Let’s think about how this type of risk assessment could be applied in the ASEAN region.

• Do you know if data on national consumption are available for your own country?
• Which organisation may have these data available?
• If national consumption data are not available, could you think of some methods to collect these data?

• Which organisation in your country, public or private, conduct studies to monitor pesticide residues in agricultural products?
• If these data are collected by an organisation other than your own, how could you get access to these data for the purpose of a risk assessment?

• How would you plan the communication of the results of such a risk assessment to the general public?
• Assuming your risk assessment would give similar results as the one of the case study, what (if any) recommendations could you think of to give to the consumers?

The risk assessment includes all four steps of a complete food safety risk assessment.

The objectives were to:

1. Assess the risk (probability and consequences) of acquiring cholera as a result of consumption of imported warm-water shrimps.
2. Compare qualitative and quantitative risk assessment approaches.

For the hazard identification, two types of data were needed:

1. Data on the presence of the organism
2. Data on the characteristics of the organism

For the exposure assessment, five important elements of the production-to-consumption chain were considered:

1. The occurrence of choleragenic V. cholerae O1 and O139
2. Harvest, post-harvest handling and transport
3. Processing and cooking
4. Distribution and retail
5. Consumption

For the hazard characterisation, four main aspects were considered:

1. Pathogen, host and food matrix factors
2. Public health outcomes
3. Number of cholera cases reported to WHO by shrimp-importing countries
4. Dose-response relationship

Data for hazard identification were obtained from a wide range of previously published scientific studies.

The risk assessment report gives all references to the studies that were used.

Data for exposure assessment were obtained from different sources, including scientific studies, industry data, and personal communications.

Data for hazard characterisation were obtained from a range of previously published scientific studies.

The dose-response relationship was calculated using a statistical model.

Results of the qualitative risk characterisation are summarised in this table.

Results of the quantitative risk characterisation are summarised in this table. 

The authors concluded that the qualitative and quantitative risk assessment approaches provided very comparable results.

However, a quantitative approach requires more input data and a higher level of detail.

The risk assessment demonstrated that there is a very low risk of developing cholera as a result of the consumption of imported warm-water shrimp.

The risk assessment makes no conclusions about the risk of developing cholera as a result of the consumption of domestic warm-water shrimp or any other source of infection.

This case study was done at a global level, and focused on a few selected importing countries. Let’s think about how this type of risk assessment could be applied in the ASEAN region.

• What do you think about the differences between a qualitative and a quantitative risk assessment?
• What are the advantages and disadvantages of either approach?
• Under which conditions would you prefer one over the other?

Consider a production-to-consumption pathway for a food chain of your choice, and select a relevant foodborne hazard.

Examples could be:

• Papaya’s and a pesticide used in papaya production
• Shrimps and antibiotic residues
• Rice and aflatoxins

What are the relevant factors that could lead to a decrease or increase of the hazard in the commodity that is consumed by the consumer?

Are they steps along the risk pathway that could lead to a concentration or dilution of the hazard, or are there steps where the hazard could reliably be eliminated from the commodity?