The Nutritional-Toxicological Conflict related to Seafood Consumption

Transcription

1 The Nutritional-Toxicological Conflict related to Seafood Consumption Isabelle Sioen PhD defence, 4 October 27 Promoters: Prof. dr. S. De Henauw Prof. dr. ir. J. Van Camp

2 Outline 1. Introduction: omega-3 fatty acids and the conflict model related to seafood consumption 2. Omega-6 and omega-3 PUFA intake of the Belgian population 3. Methodology used to study the nutritional-toxicological conflict 4. Results of the intake assessment study 5. Conclusion and topics of discussion

3 Omega-3 fatty acids: today omnipresent!

4 Omega-3 FA: scientific facts

5 Essential FA and long chain derivates (DHA)

6 Evolution of omega-3 FA in the diet Due to agricultural industry and modern food technology - omega-3 FA in food products from animal and plant origin - use of plant oils rich in omega-6 FA in processed food items

7 Evolution ratio omega-6/omega-3 Belgium?

8 Increasing the omega-3 intake omega-3 FA (EPA&DHA) Positive to health Fish consumption Nutritionaltoxicological conflict contaminants Mercury Negative to health PCBs Dioxins

9 n-6 and n-3 PUFA intake of the Belgian population 1. Objective: Intake assessment, food sources and evaluation for individual omega-6 and omega-3 poly-unsaturated fatty acids 2. Methodology: Combination of consumption data and PUFA concentration data in consumed food items Belgian recommendations for fatty acids (27) were used to evaluate the intakes

10 Consumption data: 3 sub populations 1. Flemish pre-school children (n=661; y; nov2-febr3): 3-day dietary record British Journal of Nutrition 27; 98(4): Adolescents, region Ghent (n=341; y; mar-may97): 7-day dietary record Journal of Human Nutrition and Dietetics 27; In Press 3. Young women, region Ghent (n=641; y; 22): 2-day dietary record Lipids 26; 41(5):

11 PUFA concentration data 1. Combination of data from 8 international food composition databases: The Netherlands; France; UK; USA; Finland; Canada; Denmark; Germany 2. Information from industry (margarines, cheese) 3. Calculated concentrations on the basis of recipes PUFA intake = consumption data x PUFA concentration data

12 Intake linoleic acid (omega-6) 5 Adolescents LA-intake (%E) Young women LA-intake (%E)

13 Intake alpha-linolenic acid (omega-3) 5 Adolescents ,25,5,75 1, 1,25 1,5 1,75 2, 2,25 LNA-intake (%E) 12 Young women ,25,5,75 1, 1,25 1,5 1,75 2, 2,25 LNA-intake (%E)

14 Intake long chain omega-3 PUFAs Adolescents ,,1,2,3,4,5,6,7,8 EPA&DHA-intake (%E) 4 Young women 3 2 1,,1,2,3,4,5,6,7,8 EPA&DHA-intake (%E)

15 Food sources n-6 & n-3 PUFAs (young women) 4% 35% 3% 25% 2% 15% 1% 5% % omega-6 (LA+AA) omega-3 (LNA+EPA+DPA+DHA) Total cereal products Total dairy products Total fats & oils Total fish & seafood Total fruits & vegetables Total meat, poultry & eggs Total miscellaneous Total sweet products % of contribution to total FA intake

16 Conclusions of the PUFA intake study Intake of essential PUFAs: LA intake (n-6) : reaches the recommendations LNA intake (n-3): very low compared to recommendations high LA/LNA ratio Solution: e.g. increased use of LNA rich oils in food products N-6/n-3 ratio in Belgium 8 Intake of long chain n-3 PUFAs (EPA&DHA): Depends strongly on seafood consumption Seafood consumption in Belgium very low Recommendations to consume more seafood are a possible solution

17 Conflict model omega-3 FA (EPA&DHA) Positive to health Fish consumption Nutritionaltoxicological conflict contaminants Negative to health

18 Methodology to study the conflict model Measures Biomarkers of exposure Time and money consuming Query Intake of nutrients vs. contaminants Predict Model Simulation of reality Assess intake of nutrients and contaminants Advice e.g. seafood consumption recommendations

19 Model for intake assessment Y i = v a t b v, a X BW v, i, t i C T v, a Y i : intake of a contaminant/nutrient of individual i X v,i,t : seafood consumption (species v) of individual i C v,a : concentration of a contaminant/nutrient in fish v coming from region a b v,a : probabilistic factor to express the origin BW i : body weight of individual i T: time v: fish species a: origin of the fish t: time i: individual

20 Probabilistic approach Takes into account variability of consumption, body weight and concentration data Each consumption point is combined with a concentration point of multiple compounds Consumption data Body weight data Y i = Σ v Σ t (X v,i,t C v )/(bw T) Y i = Σ v Σ t (X v,i,t C v )/ (bw T) Y i = Σ v Σ t (X v,i,t C v )/ (bw T)... Concentration data... Combined intake assessment, giving information about correlations between the intake of different compounds

21 Probabilistic approach in practice Multiple nutrients, contaminants, origins, fish species Concentration Cumulative % Ingestion rate (L/d) Consumption Cumulative % 6 4 1% 2 9% 5 3 8% 1 Cumulative % 7% 4 2 1% 6% 9% 3 1 5% 8% 2 Concentration Cumulative in drinking % 4% water (ug/l) 7% 1% 3% 6% 2% 1 9% 5% Concentration in drinking water 8% (ug/l) 1% Cumulative % 4% 7% % 1% 3% 6% 9% 2% Concentration in drinking water (ug/l) 5% 8% 1% Cumulative 1% % 4% 7% % 9% 3% 6% 8% 2% Concentration Cumulative in drinking % water (ug/l) 5% 7% 1% 4% 6% % 3% 5% 2% Concentration in drinking water (ug/l) 4% 1% 3% % 2% Cumulative 1% % % 9% 8% 7% 6% 5% 4% 3% 2% 1% % 6 Concentration in drinking water (ug/l) Concentration in drinking water (ug/l) 1% % 9% 8% 7% 6% 5% 4% 3% 2% 1% % 1% 9% 8% 7% 6% 5% 4% 3% 2% 1% % Y i = MODEL v a t b v, a X v, i, t C BW T i v, a Multiple nutrients, contaminants Bin More More More Bin Intake Cumulative % 1% 9% Cumulative % 8% 1% 7% 9% 6% Cumulative % 8% 5% 7% 4% 6% 3% 5% 2% 4% 1% Bin 3% % 2% 1% % 1% 9% 8% 7% 6% 5% 4% 3% 2% 1% % 9 1% 8 9% 7 8% Cumulative % 7% 6 6% 5 5% 4 4% 3 3% 2 2% 1 1% % Body Weight (kg) Body weight More To perform all these simulations: a software module was developed: ProbIntake UG

22 Presentation of distributions Intake (µg/kg Bin bw/day) Cumulative % More 1% 9% 8% 7% 6% 5% 4% 3% 2% 1% %

23 Databases Three databases were compiled using literature sources: 1. The origin of seafood on the Belgian market Preparing for submission to Fisheries Research. 2. A nutrient database, considering EPA+DHA, vitamin D, iodine and total fat Journal of Food Composition and Analysis 27; 2(8): A contaminant database, considering mercury, PCBs and dioxin-like compounds Human and Ecological Risk Assessment 27; 13(3):

24 Databases: conclusions Hard to find out the origin of the seafood species available on the Belgian market, traceability of seafood should be improved High intra-individual variability in the concentration of nutrients and contaminants in seafood species Need to improve the comparability of data critical to conduct human intake assessment

25 Results of the intake assessment 1. Current situation, based on REAL consumption data of 341 adolescents (1997) and 821 adults (24) Chemosphere. In review. 2. Scenario studies: can EPA-DHA recommendation be reached without toxicological concerns? Public Health Nutrition. In review.

26 Standardising the assessed intakes Nutrients: intakes are divided by dietary reference intakes (DRI) Intake > 1 = FAVOURABLE (the recommendation is reached) Contaminants: intakes are divided by tolerable daily intakes (TDI) Intake > 1 = UNFAVOURABLE (the toxicological reference value is exceeded)

27 Current nutrient intake via seafood consumption EPA&DHA 1% Favourable Cumulative probability Vitamin D Iodine 8% 6% 4% 2% Nutrient intake / DRI (log-scale) %

28 Current methyl mercury intake via seafood 1% Unfavourable Cumulative probability 8% 6% 4% 2% MeHg intake/ TDI (log-scale) %

29 Intake of dioxin-like compounds via seafood * * INcluding salmon and herring from the Baltic Sea 1% Unfavourable Cumulative probability PCDD/Fs dl PCBs Total dioxin-like compounds 8% 6% 4% 2% Intake of dioxin-like compounds / TDI (log-scale) %

30 Intake of dioxin-like compounds via seafood * * EXcluding salmon and herring from the Baltic Sea 1 Unfavourable Cumulative probability PCDD/Fs dl PCBs Total dioxin-like compounds Intake of dioxin-like compounds / TDI (log-scale)

31 Three times three scenarios

32 Scenario: MeHg versus EPA&DHA Current consumption pattern 5% lean and 5% fatty fish Only fatty fish 2E EPA&DHA (intake/dri) 1E 9E-1 8E-1 7E-1 6E-1 5E-1 4E-1 3E-1 2E-1 1x15g 2x15g 3x15g 1E-1 4E-2 5E-2 7E-2 1E-1 2E-1 3E-1 4E-1 5E-1 7E-1 1E MeHg (intake/tdi)

33 Dioxin-like compounds versus EPA&DHA Current consumption pattern 5% lean and 5% fatty fish Only fatty fish 2E EPA&DHA (intake/dri) 1E 9E-1 8E-1 7E-1 6E-1 5E-1 4E-1 3E-1 2E-1 1E-1 1E-1 2E-1 3E-1 4E-1 5E-1 6E-1 8E-1 1E 2E TotTEQ (intake/tdi)

34 Conclusions (1) Current situation as far as only seafood is concerned: General population does not reach adequate intake of the considered nutrients Methyl mercury contamination: not an issue of toxicological concern in Belgium Heavy seafood consumers can be at risk for a too high intake of dioxin-like compounds Exclusion of seafood from highly contaminated regions is needed

35 Conclusions (2) Scenario studies, independently from other food sources: EPA&DHA recommendation can be reached by consuming twice a week fatty fish three times a week a combination of lean and fatty fish Three times a week fatty fish can lead to intake of dioxin-like compounds above the toxicological reference value Positive conclusion conditional upon compliance of strict rules and regulations

36 Topics of discussion 1. Other sources were not taken into account, intake assessment via total diet is needed 2. Consumer perception: nutrition education is crucial when aiming to convince consumers 3. Sustainability aspects: Depletion of fish stocks Is aquaculture a valuable alternative? Single cell oils or metabolic engineering to create new omega-3 sources?

37 Thank you for your attention If you need tips for recipes to increase your seafood consumption: