Overview of Issues Related to the Impact of Toxic Chemicals in Chesapeake Bay Prepared by Greg Allen, EPA Chesapeake Bay Program For Briefings Conducted Fall 2007
Overview of Issues Related to the Impact of Toxic Chemicals in Chesapeake Bay • The Importance of Managing Toxic Chemicals: Ten Examples • Thoughts on Implementation Strategies for High-Priority Chemicals • Current Toxics Subcommittee Work Items • Conclusion
Chesapeake Bay Tidal Waters Impaired by Toxic Chemicals • Chemical contaminant 303(d) impairments • 67.4% percent of tidal segments have a full or partial spatial impairment due to a chemical contaminant • 95% include PCBs
2. Ubiquitous Pollutants in Chesapeake Bay • Certain toxic chemicals are ubiquitous in Bay tidal waters/sediments • PCBs * • PAHs * • Butyltins * • Ag. Herbicides + * NOAA (NOS NCCOS 47), January, 2007; + McConnell et al., 2007
3. Chesapeake Bay Fish Under Consumption Warnings • Approximately 23 different species of fish have some level of fish consumption advisory in tidal waters • Main risk drivers are PCBs, mercury, and pesticides From MDE “Fish Facts” brochure 2007
4. Striped Bass Advisories • For the commercially and recreationally important striped bass, MDE recommends less than one meal per month for the general population and no consumption for children when the fish is “trophy” (>28”). PCB contamination is primary risk, mercury is secondary risk.
5. Contaminated Sediment • “The aerial extent of observed toxicity and elevated ERMq values were consistently seen in the upper Bay, urban harbor areas, and the major western tributaries.” NOAA Technical Memorandum NOS NCCOS 47, January, 2007
6. Biomarkers of Toxic Effects in Chesapeake Bay • 2005 USFWS survey of Brown Bullhead in the South River • 53% had skin tumors • 20% had liver tumors • Scientists consider areas to be highly contaminated when skin tumors rates are above 12% and liver tumor rates are above 5%.
Chemical Impacts to Benthic Integrity • The condition of the benthos has been considered degraded or marginally degraded in more than 50% of the Bay • Biological indices indicate detectable impact of contaminants: “Diversity and number of species declined with increasing chemical concentrations while observed toxicity increased with increasing contaminant value.” • In the most stressed areas, both biological indices show decline NOAA Technical Memorandum NOS NCCOS 47, January, 2007
8. Potomac River PCB TMDL • Large-scale PCB TMDL for Potomac watershed submitted to EPA in 2007 • Objective is to ensure that the “fish consumption” use is protected • Consent decree initiated TMDL development
“Intersex fish have been found in the Potomac River in Washington, D.C., where scientists have discovered immature eggs in the sex organs of male smallmouth and largemouth bass.” 7 of 13 male largemouth showed feminine characteristics, 3 contained eggs in 2005 D.C. samples “ (Vicki) Blazer (USGS) believes the intersex abnormality cannot be blamed on just one pollutant but on several pollutants acting together … ‘They're not just chemicals used by big industry. They're pharmaceuticals, beauty products that everyone uses and discards. They're pesticides and herbicides used in yards.” 9. Emerging Endocrine Disruption September 2006
10. Increased Usage of Agricultural Pesticides • Projections for increased corn acreage in Bay Watershed could mean greater risk from atrazine and other pesticides used intensively on corn • Potential 20-60% increase in atrazine usage (based on 300K-1 mill. new acres of corn)
Endocrine Disrupting Compounds Strategy • In early 2008 the Bay Program will conduct a STAC-sponsored workshop to determine our level of understanding of the fate of EDCs in ENR wastewater systems. • Concurrently, we should promote proper disposal of pharmaceuticals.
Monitoring and Assessment New impairment indicator for 2008 Bay Health Report Effort to integrate chemicals into UMCES Report Card Stormwater monitoring in progress Communication and Education Third year of training fed facilities on Bay-Focused EMS New web site for Hg modeling workshop Toxics Today Newsletter New Toxics Characterization in 07-08 Toxics Subcommittee Work Items
Toxics Subcommittee Work Items • Implementation Ideas • Continue EMS training and promote Chesapeake Regional Challenge within Performance Track • Partner with agricultural community to promote BMPs that keep agricultural chemicals on the land • Require farm management plans for herbicides and insecticides • Push for outcomes related to reducing toxics loads: • Innovative PCB transformer retrofit program • Coal-tar sealant ban
Issues Related to the Impact of Toxic Chemicals in Chesapeake BayConclusion Toxic chemical impacts in Chesapeake Bay are similar to nutrient impacts in that the current regulatory requirements alone can not adequately protect living resources and humans. A combination of regulations and voluntary initiatives are needed to improve conditions. The Bay Program reorganization should maintain a structure to allow an appropriate balance of targeting resources to toxics in addition to nutrients.