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ENVIRONMENTAL CONTAMINANTS

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• MERCURY:
The publications below relate to research on mercury (Hg) cycling and bioaccumulation primarily in California, and more specifically at Clear Lake and the San Francisco Bay Delta regions. The Sulphur Bank Mercury Mine (SBMM) in Lake County originated as an open pit sulphur mine in the mid 1800s. As the sulphur became more contaminated with Hg (in the form of cinnabar), it switched initially to a shaft mining operation for Hg until the 1920s when it became an open pit Hg mine, resulting in over 100 metric tons of waste rock and tailings being bulldozed into Clear Lake.
 
With funding from the USEPA Superfund Program and other sources, Tom and a number of U.C. Davis colleagues developed a full-time and fully staffed research laboratory at Clear Lake (the U.C. Davis Clear Lake Environmental Research Center). A diverse team of inter-disciplinary researchers took a holistic ecosystem approach over a 15-yr period to evaluate how Hg was transported from the SBMM mine to all of the lake's physical and biological components, and how Hg was bioaccumulated into various trophic levels. They also worked with USEPA Superfund to determine potential solutions to reduce the lake's Hg contamination. In 2008, we published a Special Issue of the journal Ecological Applications that featured 17 inter-disciplinary papers on this study. See Primary Literature publications #63 and #62 for an overview of this research.
For centuries, environmental contaminants have played an enormous role in human health, as well as the health of our natural ecological communities. Most of Tom's career has focused on human impacts on our planet, especially environmental contaminants, including mining wastes (especially mercury), radioactivity, oil, thermal pollution, pesticides (DDD, DDT), and most recently the influence of greenhouse gases (especially carbon dioxide) on climate change. A few representative projects are listed below, with the various publications associated with those studies, as referenced in his publication lists.
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The Sulphur Bank Mercury Mine (foreground) on the shoreline of Clear Lake, CA from the cover of the Ecological Applications Special Issue on Clear Lake.
See mercury related Publications from Primary Literature
#s: 68. 65, 64,63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 46, 45, 43, 42, 41, 39, 33, 31.
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See mercury related Publications from Secondary Literature
#s: 92, 91, 90, 89, 88, 87, 86, 85, 84, 83, 82, 80, 78, 77, 76, 75, 74, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 58, 57, 56, 55, 54, 53, 52, 51, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, ,32, 31, 29, 28.

ADDITIONAL CLEAR LAKE REFERENCES (hot links):

• First Annual Clear Lake Science & Management Symposium

• Second Annual Clear Lake Science & Management Symposium

• RADIONUCLIDES:
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Farallon Islands Nuclear Waste Dump Site - California:
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From ca. 1945-1970, over 47,500 barrels of radioactive waste were dumped at the Farallon Islands Nuclear Waste Dump Site (FINWDS) 30 miles from the Golden Gate Bridge in San Francisco. The San Francisco Bay area receives bottom fish from the region encompassing the FINWDS. Through a grant from the California Department of Health Services, and with the cooperation of local fishermen, Tom collected and analyzed three species of bottom dwelling fishes and intertidal mussels in 1986/87 for the radionuclides Cesium-137, Plutonium-239+240, and Americium-241 at the FINWDS as well as a comparison site (Pt. Arena) at a comparable depth ca. 100 mi. north of the FINWDS. There were no significant differences between the FINWDS and Pt. Arena. However, concentrations of both 238Pu and 241Am in fish tissues (from both sites) were notably higher than those reported in literature from any other sites worldwide, including potentially contaminated sites. These results also show ~10 times higher concentrations of 239+240-Pu and ~40-50 times higher concentrations of 238-Pu than those values reported for identical fish species from 1977 collections at the FINWDS. See our 1996 article (#34) featured on the cover of the journal Health Physics.
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Pacific Nuclear Testing Grounds - Enewetak Atoll, Micronesia:
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Also see section on callianassid ghost shrimp bioturbation of radioactive fallout particles from nuclear testing at Enewetak Atoll in the MICRONESIA section of the BIOTURBATION page.
See radionuclide related Publications from Primary Literature
#s: 38, 36, 35, 34, 21, 20, 19, 18, 17, 15.
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See radionuclide related Publications from Secondary Literature
#s: 50, 30, 26, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6.
Cover article from the journal "Health Physics" featuring our study on the food web at the Farallon Islands Nuclear Waste Dump Site.
The Ivy-Mike Hydrogen bomb test at Enewetak Atoll yielded radioactive fallout, re-distributed by ghost shrimp.
• OIL:
Shortly after the Exxon Valdez oil tanker ran aground on Bligh Reef  in Prince William Sound on March 24, 1989 spilling over 11 million gallons of crude oil, Tom assembled a multi- and interdisciplinary team of ecologists, algologists, invertebrate zoologists, taxonomists and chemists to evaluate the impacts of the spill outside of Prince William Sound at 28 sites within the Shelikof Strait. They evaluated rock, cobble, mud and sand habitats for oil coverage, biological impacts, and potential for treatment and recovery.
Intertidal rock weed (Fucus) oiled from the Exxon Valdez Oil Spill.
See oil related Publications from Primary Literature
#s: 32, 31, 29.
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See oil related Publications from Secondary Literature
#s: 27, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16.
• THERMAL POLLUTION:
The Long Island Lighting Company, a steam-electric generating facility in Northport, Long Island, New York, utilizes Long Island Sound marine water for cooling. Phytoplankton and zooplankton entrained within the cooling water pass through condenser tubes and become super-heated within a matter of seconds. Utilizing a static approach, phytoplankton showed no significant differences between ambient and heated waters. However, a dynamic approach utilizing primary productivity (oxygen production), revealed significant inhibition of primary production in the thermal effluent. The magnitude of this effect decreased as the ambient temperature of Long Island Sound water decreased. Quantitatively, the Long Island Lighting Company generating facility at Northport inhibited ca. 8.0 kg of Chlorophyll-a (Chl-a)  per day, which represents ca. 1/39,000 of the total phytoplanktonic Chl-a in all of Long Island Sound. While the thermal impacts were significant locally, this one power plant did not affect a large region of Long Island Sound.
Long Island Lighting
Company in the 1970s
Long Island Lighting
Company in the 1970s
See thermal pollution related Publications from Secondary Literature
#s: 2, 1.
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