1. Why Care About Air Toxics in the NPS? Toxic deposition from Asian sources is occurring Degree of...

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Transcript of 1. Why Care About Air Toxics in the NPS? Toxic deposition from Asian sources is occurring Degree of...

1. Why Care About Air Toxics in the NPS?

• Toxic deposition from Asian sources is occurring

• Degree of risk is undetermined

• Toxic re-deposition with elevation is very likely

• Snow is an efficient pathway for toxic deposition

• Snow is the primary alpine precipitation source

• Bioaccumulation through food webs will occur

• Multiple stressors and sources (local, region, hemisphere)

• High elevation sites could be “sinks” for toxics

• Early warning sites for the rest of the continent

2. Where have we seen effects?What concentrations?

• Effects seen in Arctic

• Food web dependent (marine, fw, terrestrial)

• Fish

• Piciverous birds (eagles, falcons)

• Waterfowl (green-winged teal/Hg & PCB)

• Cause/effect relationships are poorly studied; non-lethal effects on immune system and reproduction probable

• http://www.amap.no/

3. Toxic Distribution and Effects in Western United States?

• Trans-Pacific toxics are poorly characterized• Distribution of toxics in general is very poorly

understood both spatially, vertically and temporally!

• Investigations at a few sites are beginning: amphibians in Southern Sierra; Denali NP; others?

4. Recommendations to NPS

• Develop clear objectives • Consider a robust spatial design• Sediments - history of exposure, system flux• Snow - annual and spatial loading variability• Biota - select meaningful biological indicators:

wide distribution, relatively abundant, easy to sample, known food web position

5. Advance Work

• Develop clear objectives • Consider a robust spatial (geographic) design• Integrate effort with atmospheric monitoring efforts (analyte selection)• Combine exposure and effects monitoring (snow, sediment, biota)• Create a Research Plan• Obtain very high quality analytical support• Create a Scientific Advisory Board to guide effort• Factor in adequate peer review• Strive to collaborate with Canada, Mexico?• Get more money (POP analyses are @~$500, logistics may involve

aircraft, interdisciplinary investigation team, many parks, multiyear effort)

6. What trends are predicted for toxic emissions, deposition and impacts?

• Regulations have reduced many POPs and declines in emission, deposition and impacts have been observed (DDT, Pb, HCH)

• Arctic and high latitudes may lag behind since they may function as environmental “sinks”

• Mercury is just beginning to be regulated - anthropogenic sources abound

• New Generation Pesticides (NGP)???• Impacts need much greater study to link

contaminants with effects

7. Research Gaps

• Effects are difficult - outside normal monitoring program - establish bioaccumulation

• 1o Production: Not where the wise would look for effects! But if you MUST investigate effects (get more money):

• Link effects at the individual and population level• Determine contaminant effects on eggs and larvae of

invertebrates• Investigate cumulative effects. Investigate non-lethal effects• Urgent: develop methods to assess the individual health of

zooplankton and fish larvae, mainly to establish causality between effects and environmental factors.

(emphasis on 1o Production - Aquatic?)

Problem: Possible deposition oftrans-pacific air toxics to highelevation ecosystems in N. America

Toxic substances of concernare not well established

Identify most likelytoxics substances transported to and

accumulated in N. A.Ecosystems

Probable materials Are: HCH, DDT,

PCB, & Hg

Collaboration withAtmospheric Scientists

Final List of Toxic Materials

To Evaluate• long lived• toxic

• unique origin

Probability based spatial Design - High elevation Western N. America

EffectsExposure

Biological indicator

of Bioaaccumulation

(Gammarus spp.?)

Historic LoadingLake Sediments

Annual VariabilitySnowpack

QuantitativeRegional Scale

Risk Assessment

Sediment Sampling:Sediment Sampling:• • Design matches objectivesDesign matches objectives• • Bathymetry screeningBathymetry screening• • Gradients (elev./ Lat.)Gradients (elev./ Lat.)• • Watershed type/sizeWatershed type/size• • Inflows/glaciersInflows/glaciers• • Nice to have p-chem,Nice to have p-chem,

biotic inventory,biotic inventory,sed. Ratesed. Rate

• • Importance of coresurfaceImportance of coresurface

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Coring set up for large diameter, heavy corer in remote locationIce thickness - 2 m

Core head - 50-100 kgHole diameter - 30 cm

“Lightweight” mobile coring operation21.5 diameter corerIce thickness - 1 m

83 mm ID corerCorer weight - ~15 kg max

Corer in core rack

Winch

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Key References

Macdonald, R. W., L. A. Barrie, et al. (2000). Contaminants in the Canadian arctic: 5 years of progress in understanding sources, occurrence and pathways.

The Science of the Total Environment 254: 93-234.

Carrera, G., P. Fernandez, et al. (2001). Persistent organic pollutants in snow

from European high mountain areas. Atmospheric Environment 35: 245-254.

Landers, D. H., C. Gubala, et al. (1998). Using lake sediment mercury flux ratios toevaluate the regional and continental dimensions of mercury deposition in arctic and boreal ecosystems. Atmospheric Environment 32(5): 919-928.

Muir, D. C. G., A. Omelchenko, et al. (1996). Spatial trends and historical deposition of polychlorinated biphenyls in Canadian mid-latitude and arctic lake sediments. Environ. Sci. Technol.(30): 3609-3617.

http://grida.no/amap/ [Arctic Monitoring and Assessment Program web site]