HERC Seminar 25.10.2007, Mari Vanhatalo In collaboration with Samu Mäntyniemi

1. HERC Seminar 25.10.2007, Mari Vanhatalo In collaboration with Samu Mäntyniemi Department of Biological and Environmental Sciences University of Helsinki mari.vanhatalo@helsinki.fi Fisheries Environmental and management group http://www.helsinki.fi/science/fem/ Multidisciplinary evaluation of an environmentally driven health risk: the case study of herring and dioxin(EVAHER)

2. Content • Background • Objectives and aims of the study • Key personnel and participating institutes • Methods • Progress of the study and current results • Publication plan • Results • Relevance of the study in environmental research and solving environmental problems

3. Background • Dioxins • bioaccumulate in humans and wildlife due to their lipophilic properties • are supertoxins • are merely environmental toxins ( .. a little amount as by-product of industry) • For humans a major source of dioxin is food • specifically through the consumption of fish, meat, and milk products • Herring is the most important species of the commercial fishery of Finland and the key species in the marine ecosystem of the northern Baltic Sea

4. .. • Dioxin may cause disturbances in humans • Trade-off between cost and benefits of eating fish • Several causal dependencies behind the dioxin problem are highly uncertain

5. M.Vanhatalo .. diluted by growth but persists at noticeably elevated levels even to adulthood .. 25102007 5

6. Objectives and aims of the EVAHER study • 1) to evaluate the uncertainty related to threshold values of dioxin • 2) to develop risk analysis models to assess current risks caused by herring consumption • 3) to evaluate the relative impacts of alternative ways to manage the health risk caused by herring consumption • 4) to educate one scientist to Bayesian analysis and to the modeling of links between ecosystem health and human health.

7. Personnel and institutes • Sakari Kuikka, coordinator (Professor, Fisheries Science, UHel) • Mari Vanhatalo, PhD student (Aquatic Science, UHel) • Samu Mäntyniemi, PhD (biometry, Uhel) • Other researchers : • Mr. Anssi Ahvonen, LicPhil, Mr. Jukka Pönni, MSc and Mr. Pekka Vuorinen, PhD (Finnish Game and Fisheries Research Institute), • Mr. Timo Assmuth, PhD and Mr. Heikki Peltonen PhD (Finnish Environmental Institute) • Mr Jouni Tuomisto. PhD, Docent (National Public Health Institute, Kuopio).

8. Methods • Bayesian approach • Enables researcher to quantitatively integrate interpretation of data with expert knowledge • learning process • Bayesian probability is a formalism of knowledge that allows us to reason under conditions of uncertainty • Knowledge is combined and updated by using the rules of probability calculus

9. Why Bayesian approach: The importance of assessing the uncertainty 25102007 9

10. Influence diagram/mind map/probability model

11. Publication plan • The first analysis has been published (Spring 2007) in Ambio • Human Dietary Intake of Organochlorines from Baltic Herring: Implications of Individual Fish Variability and Fisheries Management. Ambio, Vol.36, No. 2/3 • Next tasks: • Would a maximum size for herring in the human diet decrease the health risks ? • Paper 3) Variability of herring consumption among consumers (and variability of exposure from other sources?)

12. Would a maximum size for herring in the human diet decrease the health risks? & Human Dietary Intake of Organochlorines from Baltic Herring: Implications of Individual Fish Variability and Fisheries Management. Recommendation (Finnish Food Safety Agency): > 17cm , 1-2 times per month Consumers cannot choose size-selectively herring individuals nowadays, because a major part of herring is consumed in forms that obscure the original size. What would be the risk from intake of smaller herring, length ≤ 17cm (0-30g)? 25102007 12

13. EU SCF limit for all foodstuff of WHOtotal-TEq 840 pg wk-1 and limit of WHOtotal-TEq originating from herring is 275 pg WHOtotal-TEq wk-1 • Results from first analysis (Kiljunen et al. 2007) show that regulating the fishing is a far less effective way to decrease the risk than regulating the consumption of herring • Individual variability in dioxin content of herring

14. Materials, data 90 herring individuals were collected from the Bothnian Sea, northern Baltic, in June 2002. (Parmanne et al.) Human herring consumption frequencies were obtained from the survey of the Finnish National Health Institute, (J.Tuomisto et al) consumption classes 1,…,5 Classes are: 1, 2, 4, 8 or 20 times herring per month The relative frequencies of age groups in catch in 2002 were calculated from herring population estimates provided by the Finnish Game and Fisheries Research Institute. (Jukka Pönni) 25102007 14

15. Relative probability distribution of whole market herring WHO_total_TEq consentrations (pg g-1) estimated for present day (status quo 2002) and future fishing scenarios. Kiljunen et al. 2007, Ambio 25102007 15

16. Results i) small herring WHO-TEQtotal intake in decade in four main herring consumptions classes ii) status quo Ii) status quo ii) status quo 25102007 16

17. Results II WHO-TEQtotal intake in one week (small herring) i) within 15 days ii) within 40 weeks (whole pregnancy time) in four main herring consumptions classes 25102007 17

18. Conclusions Herring consumers cannot choose unless they don’t know the herring size. It is possible to reduce the dioxin risk related to herring consumption by the following means: Sort herring size-selectively in food industry. The information about the size of herring used should be passed on to the consumer Then it could be possible to reduce the dioxin risk by regulating the consumption of herring by size, if consumers could choose the small or bigger ones. 25102007 18

19. Discussion Recommendation related to breast-feeding time? What is the true dioxin intake of fetus and the baby? And risk? Different metabolism, halftime Related to different responses (tooth enamel damage, chloracne, developm. dis. etc.) Dioxin extraction of the mother during pregnancy and breast-feeding T.Vanhatalo T.Vanhatalo 25102007 19

20. Future/continuation plan after EVAHER • Paper 4) Partly included already in paper: The variance of the dioxin content in the catch and on the markets. • Paper 5) Uncertainties of the critical residue levels in herring: sensitivity between individuals • Paper 6) The overall management of risks.

21. Relevance of the study’s in environmental research and solving environmental problems • Offer methodological solutions to other fields of environmental research and management • The study brings together multiple fields of research that are dealing with the dioxin problem – integrative approach increases the relevance of basic research in different disciplines

22. Thank you for your attention! 25102007 22