Fish Consumption: Benefits and Risks for Women in

1,48
MB Childbearing Years and Young Children

137
stron

5386
ID Environmental Protection Office, Toronto Public Health

2006
rok

TABLE OF CONTENTS

EXECUTIVE SUMMARY V

CHAPTER 1 INTRODUCTION .1

1.1 Background 1

1.2 Purpose.2

1.3 Methods3

1.4 Scope 3

1.5 Summary 4

CHAPTER 2 BENEFITS OF FISH CONSUMPTION .5

2.1 Fish as a source of omega-3 fatty acids5

2.2 Dietary requirement for omega-3 fatty acids .7

2.3 Health Benefits of Omega-3 Fatty Acids .8

2.3.1 DHA and Benefits to Pregnancy.9

2.3.2 DHA and Benefits to Neurological Development 9

2.3.3 DHA and EPA Health Benefits for Adults .13

CHAPTER 3 FISH AS A SOURCE OF METHYLMERCURY AND OTHER CONTAMINANTS15

3.1 Methylmercury .15

3.1.1 Sources, Toxicokinetics and Body Burden.15

3.1.2 Effects associated with methylmercury intake from fish consumption18

3.1.2.1 Neurotoxicity 18

3.1.2.2 Reproductive Toxicity 21

3.1.2.3 Cardiovascular Effects22

3.1.2.4 Other Effects.23

3.1.3 Tolerable Mercury Intakes24

3.1.4 Allowable Levels of Mercury in Fish – ‘Action levels’ .25

3.1.5 Mercury Levels in Fish.26

3.1.6 Average Consumption of Methylmercury by Canadians .29

3.2 Other Contaminants30

3.2.1 Polychlorinated Biphenyls (PCBs) in Farmed Salmon 30

3.2.2 Polybroninated Diphenyl Ethers in Fish.36

CHAPTER 4 FISH CONSUMPTION RECOMMENDATIONS AND ADVISORIES.37

4.1 Consumption Recommendations37

4.1.1 Canada 37

4.1.2 United States.37

4.1.3 United Kingdom .38

4.2 Consumption Advisories 39

4.2.1 Canada 39

4.2.2 Province of Ontario - Sport Fish Program39

4.2.3 Ontario Public Health Association .40

4.2.4 United States.40

CHAPTER 5 METHYLMERCURY INTAKE BY FISH CONSUMPTION SCENARIO42

5.1 Methods42

5.2 Consumption Scenarios43

5.2.1 Consumption Scenarios for a Pregnant Woman and a Woman of Childbearing Age .43

5.2.2 Consumption Scenarios for a Child45

5.3 Implications of Consumption Scenarios 47

CHAPTER 6 FISH CONSUMPTION - OTHER CONSIDERATIONS.50

6.1 Identifying Low Risk Fish Species 50

6.2 Advice to High Fish Consumers 50

6.3 Fish Oil Supplements .51

6.4 The State of Global Fisheries .54

CHAPTER 7 DISCUSSION AND CONCLUSIONS .56

7.1 Discussion 56

7.2 Conclusions 63

CHAPTER 8 RECOMMENDATIONS.66

8.1 Toronto Public Health Practice Recommendations .66

8.2 Policy/Advocacy Recommendations67

8.3 Research Recommendations 68

GLOSSARY OF TERMS69

REFERENCES 74

APPENDIX A: EXPOSURE TO MERCURY FROM FISH CONSUMPTION.92

LIST OF TABLES AND FIGURES