Get access

Rapid toxicity assessment of sediments from estuarine ecosystems: A new tandem in vitro testing approach

Authors

  • B. Thomas Johnson,

    Corresponding author
    1. Environmental and Contaminants Research Center, Biological Resources Division, U.S. Geological Survey, 4200 New Haven Road, Columbia, Missouri 65201
    • Environmental and Contaminants Research Center, Biological Resources Division, U.S. Geological Survey, 4200 New Haven Road, Columbia, Missouri 65201
    Search for more papers by this author
  • Edward R. Long

    1. Coastal Monitoring and Bioeffects Assessment Division, National Oceanic and Atmospheric Agency, 7600 Sand Point Way NE, Seattle, Washington 98115, USA
    Search for more papers by this author

  • Use of trade names does not constitute U.S. government endorsement of products.

Abstract

Microtox® and Mutatox® were used to evaluate the acute toxicity and genotoxicity, respectively, of organic sediment extracts from Pensacola Bay and St. Andrew Bay, two estuaries that cover about 273 and 127 km2, respectively, along the Gulf coast of Florida, USA. The sensitivity and selectivity of these two bioluminescent toxicity assays were demonstrated in validation studies with over 50 pesticides, genotoxins, and industrial pollutants, both as single compounds and in complex mixtures. The 50% effective concentration (EC50) values of insecticides, petroleum products, and polychlorinated biphenyls determined by Microtox all tended to group around the mean EC50 value of 1.2 (0.8) mg/L. The polycyclic aromatic hydrocarbon sensitivity of Mutatox was in general similar to that reported in the Ames test. Surficial sediment samples were collected, extracted with dichloromethane, evaporated and concentrated under nitrogen, dissolved in dimethyl sulfoxide, assayed for acute toxicity and genotoxicity, and compared with reference sediments. Samples with low EC50 values, and determined to be genotoxic, were detected in Massalina Bayou, Watson Bayou, East Bay, and St. Andrew Bay–East in St. Andrew Bay as well as Bayou Grande, Bayou Chico, and Bayou Texar in Pensacola Bay. An overview of these data sets analyzed by Spearman rank correlation showed a significant correlation between acute toxicity and genotoxicity (p < 0.05). Microtox and Mutatox in tandem was a sensitive, cost-effective, and rapid (<24 h) screening tool that identified troublesome areas of pollution and assessed the potential sediment toxicity of lipophilic contaminants in aquatic ecosystems.

Get access to the full text of this article

Ancillary