Presentation on theme: "U.S. Department of the Interior U.S. Geological Survey The accuracy and protectiveness of Biotic Ligand Model (BLM) toxicity predictions with copper Christopher."— Presentation transcript:
U.S. Department of the Interior U.S. Geological Survey The accuracy and protectiveness of Biotic Ligand Model (BLM) toxicity predictions with copper Christopher A. Mebane U.S. Geological Survey, Boise, Idaho, USA Workshop on Biotic Ligand Model Principles and Applications Wilfrid Laurier University, Waterloo, Ontario, Canada May 12-14, 2008 All analyses and data summaries shown in this talk are provisional and subject to revision
In the States, Its not just a model, its the law... At least, national criteria issued pursuant to the law., # 2 March
BLM promoted to provide less stringent effluent limits Using the new [BLM-based copper] criteria effectively It is expected that the BLM-based criteria will be less stringent in low hardness waters, but possibly more stringent in harder waters. Therefore, wastewater treatment plants discharging into waters with low hardness, especially with high dissolved organic carbon, should consider performing a BLM and proposing alternative copper effluent limits as appropriate. epa_copper_criteria.htmhttp://www.cdm.com/knowledge_center/monthly_viewpoint/ epa_copper_criteria.htm (viewed April 29, 2008)
Yukon River at Eagle, Alaska USGS Photo
Yukon River USGS Photo
Uncredited photo, Columbia River between Northport, WA and Trail, BC
Northwestern soft water salmon stream, Big Soos Creek, WA Photo King County Department of Parks and Natural Resources
Extremely soft water stream USFS Photo North Fork Coeur dAlene River at Enaville, Idaho, Hardness mg/L, DOC 0.8 to 1.1 mg/L
Snake River leaving Yellowstone National Park, Wyoming (hardness mg/L, pH 7 to 8.5, DOC 0.9 to 4.5 mg/L)
Copper contaminated western mountain stream, Panther Creek, Idaho (DOC 1.1 to 4.6 mg/L, hardness 25-50, pH 7.5 to 8.6) Data from Stratus Consulting
Copper and DOC concentrations rose together during early snowmelt Data from Stratus Consulting
Extrapolating patterns to post-remedial conditions
DOC and pH data quality are important! Whats happened in September 93?
DOC and pH data quality are important!
Beware USGS DOC data prior to 1994! Columbia River between Northport, WA and Trail, BC
Colorado River downstream of Glen Canyon Dam, Arizona
Neuse River, North Carolina coastal plain
Data originally from Erickson 1996
Assuming DOC as 1.1 mg/L, HydroQuals 2003 LA50 of 7.32 (DOC not measured) Assuming DOC as 1.35 mg/L, EPAs 2003 LA50 of 3.56
Fathead minnows in low alkalinity Precambrian Shield Lakes (Data from Welsh et al., 1993). Photo courtesy of Paul Welch LA , no Mg, April 2003 DOC 100% reactive as 90% FA, 10% HA
DOC 50% Cu-reactive LA , no Mg (Recalculated from EPA 2003) DOC 100% Cu-reactive LA , includes Mg, ( ) (default)
Model LA50: 7.32 nmol Cu/g gill Modified LA50: 0.2 nmol Cu/g gill Fathead minnows in low alkalinity South Carolina piedmont streams (VanGenderen et al., 2005).
(top) DOC 50 % Cu-reactive, LA50: nmol Cu/g gill (bottom) DOC 100% Cu- reactive, LA50: 0.2 nmol Cu/g gill Using EPAs 2003 updated dataset and assuming 50% of DOC is Cu- reactive (data from VanGenderen et al., 2005).
Fatmucket, Lampsilis siliquoidea < 0.3mm Data from Ning Wang, USGS, Columbia, Missouri, et al., in prep., Acute tests in waters with variable hardness and different DOC sources Photos by Doug Hardesty, USGS
A. Assume DOC is 100% reactive as 90% FA, 10% HA, (LA nmol Cu/g gill) Fatmucket B. Assume DOC is 50% reactive as FA ( (LA nmol Cu/g gill) B. A.
Fatmucket mussel: hardness vs. BLM as predictor of toxicity y = 0.37x r 2 = 0.05 P =0.2 (pooling all groups) y = 0.96x r 2 = 0.9 P <0.001 (pooling all groups) 95% prediction bands
Escanaba River, Michigan photo, wikipedia.org DOC 50% Cu-reactive LA , no Mg (Recalculated from EPA 2003) DOC 100% Cu-reactive LA , includes Mg, ( ) (default) Ceriodaphnia dubia
Hyalella azteca Doug Hardesty, USGS
Assume DOC is 50% reactive as FA Assume DOC is 100% reactive as 90% FA, 10% HA Rainbow trout flow-through tests using natural and lab waters, DOC <0.11 to 2.0 mg/L. Welsh, Lipton, and Maest, (Stratus Consulting) Josh Lipton, Stratus Consulting <
Assume DOC is 50% reactive as FA Assume DOC is 100% reactive as 90% FA, 10% HA Chinook salmon flow-through tests using natural and lab waters, DOC 0.11 to 1.4 mg/L. Welsh, Lipton, and Maest, (Stratus Consulting) Josh Lipton, Stratus Consulting
Rainbow trout, renewal exposures BLM Predicted vs. observed rainbow trout LC50s, in renewal tests using lab and site waters, hardwater, DOC from <1 to 11 mg/L, 3 of 4 seasonal rounds of testing (all data from the 1 st of 4 rounds discarded for questionable DOC data). ENSR Development of site-specific water quality criteria for copper in the upper Clark Fork River: Phase III WER Program testing results. ENSR Consulting and Engineering, , Fort Collins, Colo. Assume DOC is 50% reactive as FA Assume DOC is 100% reactive as 90% FA, 10% HA
Some Bad News Rainbow trout 96h LC50s, uniform total hardness with varying Ca and Mg, uniform low DOC, Welsh et al 2000 Testing DOC equivalents that matched natural DOM for binding affinity and complexation. DOC equivalents ranged O.3 to 16 mg/L, (actual DOC mass 0.11 to 0.84 mg/L) in lab water of with hardness of 24 mg/L CaCO3, Marr et al 1999, Panther Creek DOC
Chronic EC10s Rainbow trout (30-120d growth) Besser et al, 2005 Hansen et al, 2002 Marr et al., 1996 Seim et al Brook trout (2-22 months) McKim et al. 1971, 1974 Sauter et al Fathead Minnow (21-days to 11 months) Mount 1968 Welsh 1996 Besser et al Chinook salmon, 120d (treated as a rainbow trout) Chapman 1982
Reductions in the olfactory response to a natural odorant (serine) following short-term (30 min) exposure to 20 µg/L dissolved copper (McIntyre et al., ES&T, 2008) Photo: Carla Stehr, National Marine Fisheries Service, Seattle
Shayler Run, Ohio, USA Stream experimentally dosed with copper, Integrated long-term field, streamside, and laboratory toxicity studies High calcium limestone geology DOC from natural and sewage sources Geckler and others, Validity of laboratory tests for predicting copper toxicity in streams. EPA 600/ Photo from Geckler and others, 1976
BLM and field effects –Ohio Stream Threshold for adverse effects from Full life cycle streamside toxicity tests with native fish Fish behavioral changes in stream Cu (µg/L) BLM chronic criterion Safe from adverse effects (range)
Convict Creek, California, USA Sierra Nevada stream experimentally dosed with copper for 1 yr Measured effects on stream metabolism and macroinvertebrate community Low calcium granitic geology Most BLM parameters measured – except DOC Single DOC site value of 3.7 mg/L; average DOC in High Sierra Lakes estimated at 1.8 mg/L. Photo courtesy of Daniel Dawson, Sierra Nevada Aquatic Research Laboratory
BLM and field effects - Sierra Nevada stream Copper (µg/L) Sources: Leland and Carter, Freshwater Biology, 1984, 1985, 1989 Brooks and others, Ecosystems, 2005
BLM and experimental streams New River near Blacksburg, VA, New River Valley Bird Club Macroinvertebrate exposures in August 1987, no DOC data pH and inorganic data similar, assuming DOC is similar Clements et al., CJFAS., 1988 Clements et al., Aq. Tox., 1989
I think I learned... 1.BLM performed well across a broad range of waters and with diverse taxa 2.Paucity of chronic toxicity data from varied waters. Chemosensory testing valuable, esp. tests of whether effects are ecologically relevant 3.Experimental stream studies could be compelling 4.BLM too sensitive to DOC? Assuming 100% of DOC is Cu-reactive may be a factor. Overprotective at low DOC and underprotective higher DOC. 5.Assuming 50% of DOC is Cu-reactive fulvic acid improved predictions in most datasets from natural waters. No datasets were made much worse by the 50% AFA assumption. 6.Adding Mg to the model not helpful in these datasets. Perhaps limit to site-specific situations where Mg is important. 7.Emphasis on equilibrating waters in FT tests seems misplaced. 8.Quality of DOC and pH measurements critical. Recommend DOC detection to at least 0.3 mg/L in field data, 0.1 if testing synthetic waters