Pesticide Fate Research Group
The central coast of California is a region with intensive agricultural activity and rapid urban growth and, correspondingly, high pesticide use. The three major Central Coast rivers – Pajaro, Salinas, and Santa Maria – provide both freshwater and estuarine habitat, as the lower rivers and adjacent coastal lagoons form small estuaries in each case. All three rivers receive major inputs of agricultural drainage, contain elevated concentrations of current-use pesticides, and exhibit water and sediment toxicity attributable to organophosphate and pyrethroid pesticides. In addition to potential impacts on the riverine macroinvertebrate communities, the transport of these pesticides to the coastal estuaries may affect early life stages of commercial marine and threatened anadromous fish species. The goal of this project is to assess the occurrence, fate, and toxic effects of current-use and legacy pesticides on invertebrates and fish in these central California estuaries. Project is in collaboration with University of California at Davis and is funded by the California State Water Resources Control Board. More information about the toxicology research and Granite Canyon UC Davis Marine Pollution Studies Laboratory (MPSL) http://www.envtox.ucdavis.edu/GraniteCanyon/GraniteCanyon.htm
Smalling, K.L., and Orlando, J.L., 2011, Occurrence of pesticides in surface water and sediments from three central California coastal watersheds, 2008–09, U.S. Geological Survey Data Series 600, 70 p. http://pubs.usgs.gov/ds/600/pdf/ds600.pdf
Smalling, K.L, Kuivila, K.M, Orlando, J.L., Phillips, B.M, Anderson, B.A., Siegler, K., Hunt, J.W., Hamilton, M., 2013, Environmental fate of fungicides and other current-use pesticides in a central California estuary, Marine Pollution Bulletin, vol 73. p. 144-153. http://dx.doi.org/10.1016/j.marpolbul.2013.05.028
Anderson, B, Phillips, B, Hunt, J, Siegler, K, Voorhees, J, Smalling, K, Kuivila, K, Adams, M. 2010, Watershed-scale Evaluation of Agricultural BMP Effectiveness in Protecting Critical Coastal Habitats: Final Report on the Status of Three Central California Estuaries, Final Report to the California State Water Resources Control Board, 117 p. http://www.waterboards.ca.gov/water_issues/programs/swamp/docs/coast_study/estuaries_final%20_rep_ten.pdf
Invertebrates have long been used as resident sentinels for assessing ecosystem health and productivity. The shore crabs, Hemigrapsus oregonensis and Pachygrapsus crassipes, are abundant in estuaries and beaches throughout northern California and have been used as indicators of habitat conditions in several salt marshes. Reproductive impairment in crab embryos, including developmental abnormalities, hatching success and larval survival, has been correlated with elevated concentrations of contaminants in salt marsh sediment. Typically embryos on the outer edge of the clutch in direct contact with the sediment had higher contaminant burdens and abnormalities compared to those positioned on the interior of the brood. Organic contaminants in sediments, including current-use and legacy pesticides were directly related to the prevalence of developmental abonormalities in these shore crabs. Preliminary results of the project indicate that embryos are an effective sink for organic contaminants in the environment and have the potential to be good indicators of ecosystem health, especially when contaminant body burden analyses are paired with reproductive impairment assays. Future work will involve concurrent analyses of pesticides in sediments and crab embryos with measurements of reproductive abnormalities in contaminated Northern California salt marshes. Project is in collaboration with University of California at Davis and is funded by the USGS Toxic Substances Hydrology Program.
Smalling, K.L., Morgan, S., and Kuivila, K.M., 2010, Accumulation of current-use and organochlorine pesticides in crab embryos from northern California, USA, Environ. Toxicol. Chem., v. 29, no. 11, p. 2593-2599.
At present, there are no commonly accepted standard procedures for collecting, transporting, storing, and handling surface water and sediment samples that are to be tested for pyrethroids. Losses of pyrethroids on sampling equipment and sampling and testing container walls may be as high as 50%, confounding interpretation of analytical and toxicity test results. Sampling approach, sampling and laboratory container material, and handling procedures have been found by researchers to have significant influences on the losses of pesticides on container walls. Determining the optimum procedures and disseminating a validated SOP to laboratories and surface water monitoring programs will yield comparable data and environmental assessments leading to meaningful and measurable environmental outcomes for assessing potential effects of pyrethroid pesticides. Project is funded by the U.S. Environmental Protection Agency.
Hladik, M.L., Orlando, J.L. and Kuivila, K.M., 2009, Collection of pyrethroids in water and sediment matrices: development and validation of a standard operating procedure: , USGS Scientific Investigations Report 2009-5012, 22 p.
Hladik, M.L., Smalling, K.L. and Kuivila, K.M., 2009, Methods of analysis—determination of pyrethroid insecticides in water and sediment using gas chromatography/mass spectrometry: , U.S. Geological Survey Techniques and Methods Report 5-C2, 18 p.