DOVER –Updated consumption advisories for fish caught in Delaware waterways show some of the most significant improvements in fish tissue contaminant concentrations since the state began assessing contaminants in fish in 1986, the Department of Natural Resources and Environmental Control (DNREC) and the Department of Health and Social Services’ Division of Public Health (DHSS/DPH) announced today. Fish consumption advisories are recommendations to limit or avoid eating certain fish caught in local waters that alert people to the potential health risks of eating contaminated fish. The latest advisories come from recent data collected and analyzed from fish caught in New Castle County waterways.
“Overall, the updated advisories are good news for an area of our state that has historically been challenged by the impacts of legacy contaminants,” said DNREC Secretary David Small. “The improvements we’re seeing indicate that collaborative efforts among state, federal, local, and industry partners to address contaminants, along with DNREC’s innovative toxics assessment and restoration projects, are making a difference. This progress is also the result of significant investments in wastewater and stormwater infrastructure and cleanup technologies. If we are to achieve our goal to accelerate the cleanup of remaining contaminants and restore our waterways in the shortest time possible, we will need the technical and financial resources to make that happen.”
Less restrictive advisories were issued for seven waterways – the tidal and non-tidal Christina River, Little Mill Creek, tidal Brandywine River, tidal White Clay Creek, and upstream and downstream portions of Shellpot Creek – a result of long-term improvements in reducing contaminants in fish caught in these waterways. A more restrictive advisory was issued for Red Clay Creek due to higher levels of some contaminants, while the advisories for two waterways, the non-tidal Brandywine River and non-tidal White Clay Creek, were unchanged and remain the same as for 2015.
“I applaud DNREC’s continuing efforts to clean up our state’s waterways, which, in turn, reduces the restrictions on fish consumption,” said DHSS Secretary Rita Landgraf. “The Division of Public Health would like to remind everyone that consuming fish is an important part of a healthy diet because they contain high-quality proteins along with other essential nutrients, are low in saturated fat, and contain omega-3 fatty acids. This updated advice will help all of us make informed healthy decisions about the right amount and right kinds of fish that our families should eat from Delaware’s waterways.”
Many of the contaminants that prompt fish advisories in Delaware are “legacy pollutants” – chemicals, such as polychlorinated biphenyls (PCBs), the banned insecticide DDT, and dioxins and furans that were released into waterways in significant quantities in the past. These legacy pollutants are slow to break down in the environment and can accumulate in fish and in bottom sediments of lakes, streams and estuaries.
The improvements in consumption advisories are largely the result of declining PCB concentrations in fish. Tidal areas of the Christina and Brandywine Rivers and Shellpot Creek, historically some of the most contaminated areas in the state, have shown decreases of PCB concentrations of 50 to 60 percent in the last eight years. The reduction in PCB levels is attributed to several efforts, including state-of-the-science testing to identify, prioritize, and control remaining sources of contaminants and to innovative clean-up strategies, including adding activated carbon and quicklime to sediments that bind contaminants and limit their transfer to the water and fish. In addition, DNREC and its partners, including the Delaware River Basin Commission, New Castle County Special Services, the City of Wilmington, state environmental agencies in Pennsylvania and New Jersey, and industrial facilities, have been working cooperatively on strategies and projects that implement the Delaware Estuary total maximum daily load (TMDL) pollution limits, since first established in 2003.
The latest advisories encompass New Castle County waterways and include:
Tidal Christina River. The advisory for the Tidal Christina River between Smalley’s Dam (near Christiana) to the Delaware River was updated to less-restrictive advice that includes two areas:
- Area upstream of the Peterson Wildlife Refuge to Smalleys Dam. Less restrictive advisory:
The current advice of “eat no fish” caught from this area has been revised to “eat no more than 12 eight-ounce meals of fish per year.” The advice also applies to Nonesuch Creek, a tidal tributary of the Christina. This increase in allowable fish consumption is significant and can be attributed to improved water quality flowing from the non-tidal portion of the Christina River into the upper tidal portion of the River. PCBs are the primary contaminant of concern.
- Area between the Peterson Wildlife Refuge downstream to where the Christina River empties into the Delaware River. Less restrictive advisory:
For the general adult population, the current advice of “eat no fish” has been updated to “eat no more than one eight-ounce meal of fish per year.” The modest easing of the advice is largely attributed to falling concentrations of PCBs – approximately 50 percent from 2007 to 2015. The new advice for this area is consistent with the tidal Delaware River, into which the Christina River flows. Despite improvements in PCBs, they remain the primary contaminant of concern.
Non-Tidal Christina River. Less restrictive advisory:
The non-tidal Christina River runs from its headwaters north and west of Newark downstream to Smalleys Dam. The existing advice of “eat no more than six eight-ounce meals of fish” has been doubled to “eat no more than 12 meals per year.” The single contaminant of concern is Dieldrin, a chemical that was used in the past as an insecticide for termite control. PCBs and chlordane are no longer contaminants of concern.
Little Mill Creek. Less restrictive advisory:
A tributary of the Christina River, Little Mill Creek’s headwaters are in Greenville. The Creek flows southward through Elsmere, Canby Park, and the Peterson Wildlife Refuge and empties into the tidal Christina south of Wilmington.
The existing fish consumption advisory is to “eat no fish.” New data and assessment found that the current advice can be less stringent and has been revised to “eat one eight-ounce meal of fish per year.” The chemicals of concern include PCBs and chlorinated pesticides. Revising the advisory to “one meal per year” is consistent with the recommended advice for the lower reach of the tidal Christina into which the Little Mill Creek flows.
Tidal Brandywine River. Less restrictive advisory:
The Brandywine River is the largest tributary of the Christina River. The tidal Brandywine covers the area between Baynard Boulevard in Wilmington downstream to its confluence with the Christina River.
The existing fish consumption advisory is to “eat no fish.” The advice is being increased to “eat no more than two eight-ounce meals of fish per year.” The primary chemical of concern continues to be PCBs, however, PCB concentrations in fish have dropped significantly – approximately 59 percent from 2007 to 2015. The reduction is the result of steady cleanup efforts at the Amtrak former fueling facility in Wilmington and other projects. DNREC and the EPA are working with Amtrak on a plan to fully remediate the site, with the goal of further easing the fish advisory in the future.
Non-Tidal Brandywine. No change in existing advisory:
The non-tidal Brandywine runs from the Delaware/Pennsylvania state line to the head of tide near Baynard Boulevard in Wilmington. The data and assessment supports keeping the existing advice to “eat no more than six eight-ounce meals of fish per year.”
Tidal White Clay Creek. Less restrictive advisory:
The lower three miles of the White Clay Creek are tidal between the mouth of the creek and Route 4 in Stanton. Hershey Run, which has a history of contamination, flows into the tidal White Clay Creek. The advisory was updated from “eat no fish” to “eat no more than one eight-ounce meal of fish per year.” PCBs remain the primary contaminant of concern.
Non-Tidal White Clay Creek. No change in existing advisory:
The non-tidal White Clay Creek originates in Chester County, Pennsylvania and flows into Delaware north of the City of Newark. The existing advice of “eat no more than 12 eight-ounce meals of fish per year” is being retained and the primary contaminant continues to be PCBs.
Red Clay Creek. More restrictive advisory:
The Red Clay Creek, which has a long history of contamination in Pennsylvania and Delaware, flows into Delaware south of Kennett Square, Pa. and north of Yorklyn, Del. New data and assessment found that the recommended meal advice needs to be more stringent – from “eat no more than six meals per year” to “eat no more than three meals per year.” PCBs and dioxins and furans are retained as contaminants of concern and chlorinated pesticides added.
In recent years, fish caught near the Pennsylvania/Delaware state line have shown an increase in the concentration of the banned insecticide, DDT, and its breakdown products, suggesting the source or sources of this contamination may be in Pennsylvania. DNREC and environmental officials in Pennsylvania are working cooperatively to assess and control the contamination. Follow-up actions will include sampling areas for contamination to confirm that sources are being controlled.
Shellpot Creek. The headwaters of Shellpot Creek are located near Talleyville and its outlet is in the far eastern portion of Wilmington, just north of the Cherry Island landfill. The advisory was updated to less-restrictive advice that includes two areas:
- Upstream of Governor Printz Boulevard. Less restrictive advisory:
The current advice of “eat not more than one eight-ounce meal of fish per year” has been revised to “eat not more than two eight-ounce meals per year.” The contaminant of concern is Dieldrin and its presence in the creek upstream of Governor Printz Boulevard is likely the result of heavy usage of Dieldrin in the past, primarily as an insecticide to control termites.
- Downstream of Governor Printz Boulevard. Less restrictive advisory:
The current advice of “eat no fish” has been revised to “eat no more than one eight-ounce meal of fish per year.” Although PCBs continue to be the primary chemical of concern, concentrations of PCBs have dropped significantly in waters downstream of Governor Printz Boulevard, a result of less pollution entering the Creek and improvements in the Delaware River.
In addition to the advisories mentioned above, DNREC and DHSS remind the public of the general statewide fish consumption advisory issued in 2007:
- Eat no more than one meal per week of any fish caught in Delaware’s fresh, estuarine and marine waters. This advisory applies to all waters and fish species not otherwise explicitly covered by an advisory.
The statewide advisory is issued in an abundance of caution to protect against eating large amounts of fish or fish that have not been tested, or that may contain unidentified chemical contaminants. Delaware issues more stringent advice for specific waters when justified by the data. One meal is defined as an eight-ounce serving for adults and a three-ounce serving for children.
People who choose to eat fish caught in Delaware waters in spite of the consumption advisories can take steps to reduce exposure. Contaminants tend to concentrate in the fatty tissue, so proper cleaning and cooking techniques can significantly reduce levels of PCBs, dioxins, chlorinated pesticides and other organic chemicals. Larger fish tend to have higher concentrations. To reduce the amount of chemical contaminants being consumed:
- Remove all skin
- Slice off fat belly meat along the bottom of the fish
- Cut away any fat above the fish’s backbone
- Cut away the V-shaped wedge of fat along the lateral line on each side of the fish
- Bake or broil trimmed fish on a rack or grill so some of the remaining fat drips away
- Discard any drippings; do not eat drippings or use them for cooking other foods.
However, consumers are cautioned that these techniques will not reduce or remove unsafe levels of mercury from fish.
A chart which shows all fish consumption advisories for Delaware waters, including the revised advisories issued today, can be found on DNREC’s web site. The revised advisories will be reflected in the 2017 Delaware Fishing Guide available at tackle shops and fishing license dealers.
For more information, contact Dr. Richard Greene, DNREC Division of Watershed Stewardship, 302-739-9939.
Visit the following U.S. government websites for information on federal fish consumption advisories, on mercury in fish and shellfish, and on how to safely select and serve fresh and frozen fish.
- U.S. Environmental Protection Agency:
- U.S. Food and Drug Administration:
Vol. 46, No. 209