PARENT SESSION
SA4 - Ecotoxicology and Risk Assessment of Explosives
Chair: Steevens, Jeffery1, 1 3909 Halls Ferry Road, Vicksburg, Mississippi, USA
Co-chair: Lotufo, Guilherme2, 2 3909 Halls Ferry Road, Vicksburg, Mississippi, USA
8:00 AM to 12:00 PM - Sunday, 17 November 2002
Room Ballroom F
(038) Consequences of sunbathing under the influence of ordnance compounds.
Carr, R. Scott*,1, Nipper, Marion3, Biedenbach, James1, Hooten, Russell1, Miller, Karen2, 1 USGS, CERC, Marine Ecotoxicology Research Station, Corpus Christi, TX, USA3 Texas A&M University-Corpus Christi, Center for Coastal Studies, Corpus Christi, TX, USA2 Naval Facilities Engineering Service Center, Port Hueneme, CA, USA
ABSTRACT- It is well recognized that both the photo-transformation and photo-activation of PAHs by ultra-violet radiation (UV) can enhance their toxicity to aquatic organisms. Previous studies indicated that several ordnance compounds (nitroaromatic and nitramines) in seawater were acutely and chronically toxic to marine organisms (SETAC-Europe, 1999), but very little information is available on the effects of UV radiation on their biological effects. Due to their status as munitions and explosives of concern (MECs), particularly in some inlets of Northwestern US, picric acid (trinitrophenol) and 2,6-dinitrotoluene (2,6-DNT) were selected for photo-transformation and photo-activation studies in marine waters. Filtered seawater was spiked with these nitroaromatic compounds and exposed to simulated solar radiation (SSR), at constant temperature of 10°C. HPLC measurements conducted over a 3-week period indicated that picric acid was not photo-transformed. 2,6-DNT, on the other hand, started to photo-transform upon initiation of the exposure and none of the original compound was left after a 72 hours under SSR. One transformation peak was seen in HPLC chromatograms, and its identity and toxicity to marine organisms is under investigation. Similar to the effect of SSR on the photo-transformation, no photo-induced toxicity (photo-activation) was observed for picric acid in the sea urchin fertilization test, whereas the toxicity of 2,6-DNT was strongly enhanced. Further assessments of the photo-activation of 2,6-DNT and picric acid after more prolonged exposures to the parent compounds prior to exposure to SSR are under way. Tests will be performed with marine copepods and polychaetes and results and environmental implications will be discussed.
Key words: ordnance compounds, marine toxicity, photo-transformation, photo-activation