State of Delaware Perspective on Seafood Health Risks & Benefits

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1 State of Delaware Perspective on Seafood Health Risks & Benefits Framing the Message About Seafood Conference September 20 21, 2011 University of Delaware Newark, DE Rick Greene Delaware DNREC, Watershed Assessment Dover, DE

2 Outline Background: Delaware & our experience with fish tissue monitoring & advisories Assessing risks & acknowledging benefits Summary & future direction Questions

3 Delaware Land & Water Resources Small State with diverse land, water & biological resources. Fresh, free-flowing streams in the north; fully marine waters in the south; estuarine waters in between. Urban/industrial uses in northern DE resulted in significant contaminant release to surface water. Still dealing with the legacy of having been the Chemical Capital of the World

4 History of DE Fish Advisory Program Pre-1990s advisories reactionary & based on exceedance of FDA action & tolerance levels. Early 1990s Revelation: FDA values not designed to protect local anglers. Also, DE had highest CA mortality rate in US. Proactive, risk-based approach developed in 1993 along with signing of DNREC/DHSS MOU DE Fish Contaminants Committee Systematic approach to monitoring, assessment & communication of results Consistent with EPA national guidance Program still in place, but $ tight

5 DE Fish Consumption Advisories 23 in place as of First 1986, last All issued as joint action of the Secretary of DNREC & Secretary of DHSS. Highest contamination (& most restrictive advice) is in the tidal Delaware River, tidal Christina basin & C&D Canal. Primary contaminant of concern is PCBs. Others include DxF, OC pesticides, & mercury. GOAL: Voluntary reduction of exposure until cleaned up.

6 Assessing Health Risk Risk = dose x toxicity. Dose depends on conc. in the fish; BW of receptor; meal size and consumption rate; exposure & lifetime duration. Receptors include ave adult sports angler; women of childbearing age; and young children. Cancer and non-cancer considered. Toxicity values (q* and RfD) from EPA s IRIS and HEAST databases, plus ATSDR Tox Profiles Plot risk assuming 1 meal/yr to 52 meals/yr Identify max. number of meals/yr associated with a cumulative cancer risk of 10-5 and Hazard Index of 1 for non-cancer effects

7 5 Non-Cancer Risk as a Function of Fish Consumption Prime Hook Creek and Waples Pond 4 Key idea is to identify how much fish can be eat from a waterway and keep health risk low. Child (3 oz. meal size) Hazard Index Adult (8 oz. meal size) 0 (12.7) (23) No. of Meals Per Year

8 Additional Insights from the Data PCB concentrations are much higher in the northern part of the State but are falling all over. Accumulation depends on the truly dissolved concentration in the water, lipid content of the fish and hydrophobicity. Trophic position also important. Taken Together: Lean, marine species that are lower on foodchain are less contaminated with organic contaminants.

9 10 Mean DxF TEQs in DE Estuary Fish Zones 2-5 WHO 2005 TEFs DxF TEQ, (pptr ww fillet) C(t) = 9.84 exp[ t] t 1/2 = 10.8 yrs Values are Mean ± S.E. among all samples across Zones 2-5 for a particular year.

10 PCBs in Delaware Estuary Striped Bass River = Cherry Island Flats River = Cherry Island Flats River > Bay PCB River > PCB Bay Falling both sites Levels falling both sites

11 Total PCB vs Lipid in Biota Christina Total PCB, (ng/g ww) Channel Catfish Menhaden Spottail Shiner Eastern Silvery Minnow Grass Shrimp Corbicula Periphyton Spatterdock Seeds Lipid, (%)

12 The Big Tuna Species: Bluefin tuna caught July 2, 2005; Hot Dog Canyon (~40 mi. E of IR Inlet) 873 pounds, 9 6 long, 6 6 girth. New DE record by > 500#. Age from charts: 30 years +/- 10 yrs. Fisherman donated several steaks to DNREC for chemical analysis.

13 2.1 Trophic Increase of Mercury in Coastal Foodchain Total Mercury, (ppm ww fillet) X Trophic Increase (BMF) DE & EPA criterion = 0.3 ppm 0.0 Large Bluefish Giant Bluefin Tuna

14 Communicating Risks & Benefits Delaware s fish advisory program has been driven largely by consideration of contaminant data & health risks (consistent with DNREC s & DHSS s core missions). However, health benefits have been qualitatively & prominently acknowledged. Consider the following language within Delaware s fish advisory

15 Acknowledged Benefits Fishing is an important activity in Delaware s inland and coastal waters. Among the benefits provided by fishing are quality recreational opportunities, direct and indirect input to the local economy, food for recreational anglers, and food for the commercial marketplace. Fish are a good source of readily digestible protein. They are low in fat and sodium, and the unique types of fats found in fish are believed to provide cardiovascular benefits. Despite the general benefits of fishing and fish consumption, there has been a growing concern regarding the presence of chemical toxins in the flesh of finfish and shellfish taken from Delaware waters and the associated health risk to anglers and their families who consume their catch Delaware Fish Guide Eating fish in moderation and as part of a healthy diet may provide cardiovascular and other health benefits. Fish consumption advisories are issued to help people make informed decisions that will maximize the health benefits of eating fish while minimizing the risk of exposure to potentially harmful chemicals. Fish Smart, Eat Smart: A Guide to Eating Sport Fish Caught in Delaware

16 All Elements of Delaware Advisory Acknowledgement of general benefits List of waters, species & sizes under advisory Contaminants of concern Meal frequency advice, including for high-risk groups Proper trimming/cooking techniques to minimize risks Sources of contamination (if known) & what s being done to address the sources Who to call for additional information

17 Getting the Message Out Press release at time advisory issued Metal & Tyvek signage at access points Delaware Annual Fishing Guide Fish Smart, Eat Small Trifold DNREC Web Site PSAs in local newspapers & radio broadcasts WICs (State Public Health Centers) Public Events (e.g., State Fair, Coast Day) Presentations to interest groups Direct response to public inquiries

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20 Summary Delaware has placed a high premium on collecting the best possible data to support its assessments. We have used an abundance of caution in issuing fish advisories to protect local fishermen, their families and friends who consume their catch. We have aggressively investigated & cleaned up sources within our control with the goal of lifting advisories. Slow process. As contaminant levels in the fish have dropped, several advisories have been eased. In our view, risks still outweigh benefits for many locally caught fish, particularly upstate & in top predators. However, we remain open to a quantitative risk/benefit framework, so long as it remains protective.

21 Questions?

22 Accomplishments Along the Way Informed the public and raised the issue to regional prominence. Linked problems to sources & continue to leverage cleanups. First State in US to incorporate congener-specific, high resolution testing for PCBs in fish. DxF testing also largely unique among States. Yields better R.A. + forensic fingerprints. One of few States in the US to examine PBDEs in fish. Also one of the few States to consider arsenic speciation. Comprehensive compilation of data for the DE Estuary. Harmonized advice for Delaware Estuary with NJ. Performed fish consumption & advisory awareness surveys. Completed academic research on linkage between foodchain, sediment and water column (bioaccumulation).