Effects-based spatial assessment of contaminated estuarine sediments from Bear Creek, Baltimore Harbor, MD, USA

• Published in: Environmental science and pollution research international Vol. 24; no. 28; pp. 22158 - 22172
• Main Authors: Hartzell, Sharon E., Unger, Michael A., McGee, Beth L., Yonkos, Lance T.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.10.2017; Springer Nature B.V
• Subjects: Acute toxicity; Amphipoda - drug effects; Animals; Aquatic Pollution; Aromatic hydrocarbons; Atmospheric Protection/Air Quality Control/Air Pollution; Baltimore; Biosensors; Chemical analysis; Chromium; Complexity; Contaminants; Contaminated sediments; Contamination; Creeks; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental Monitoring - methods; Environmental science; Estuaries; Geologic Sediments - chemistry; Heavy metals; Historic sites; Hydrocarbons; Leptocheirus plumulosus; Lethality; Nickel; Persistent organic pollutants; Petroleum hydrocarbons; Pollutants; Polycyclic aromatic hydrocarbons; Pore water; Quality assessment; Receptors; Research Article; Risk assessment; Rivers - chemistry; Sediment pollution; Sediments; Soil contamination; Toxicity; Toxicity testing; Toxicity Tests; Trace metals; Waste Water Technology; Water Management; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - toxicity; Water Pollution Control; United States > US; Pore water; Sediment chemistry; Sediment toxicity; Persistent organic pollutants; Trace metals; Leptocheirus plumulosus
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-017-9667-0

Estuarine sediments in regions with prolonged histories of industrial activity are often laden to significant depths with complex contaminant mixtures, including trace metals and persistent organic pollutants. Given the complexity of assessing risks from multi-contaminant exposures, the direct measurement of impacts to biological receptors is central to characterizing contaminated sediment sites. Though biological consequences are less commonly assessed at depth, laboratory-based toxicity testing of subsurface sediments can be used to delineate the scope of contamination at impacted sites. The extent and depth of sediment toxicity in Bear Creek, near Baltimore, Maryland, USA, was delineated using 10-day acute toxicity tests with the estuarine amphipod Leptocheirus plumulosus , and chemical analysis of trace metals and persistent organic pollutants. A gradient of toxicity was demonstrated in surface sediments with 21 of 22 tested sites differing significantly from controls. Effects were most pronounced (100% lethality) at sites proximate to a historic industrial complex. Sediments from eight of nine core samples to depths of 80 cm were particularly impacted (i.e., caused significant lethality to L. plumulosus ) even in locations overlain with relatively non-toxic surface sediments, supporting a conclusion that toxicity observed at the surface (top 2 cm) does not adequately predict toxicity at depth. In seven of nine sites, toxicity of surface sediments differed from toxicity at levels beneath by 28 to 69%, in five instances underestimating toxicity (28 to 69%), and in two instances overestimating toxicity (44 to 56%). Multiple contaminants exceeded sediment quality guidelines and correlated positively with toxic responses within surface sediments (e.g., chromium, nickel, polycyclic aromatic hydrocarbon (PAH), total petroleum hydrocarbon). Use of an antibody-based PAH biosensor revealed that porewater PAH concentrations also increased with depth at most sites. This study informs future management decisions concerning the extent of impact to Bear Creek sediments, and demonstrates the benefits of a spatial approach, relying primarily on toxicity testing to assess sediment quality in a system with complex contaminant mixtures.