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Predicting the Chronic Effects of PAHs using the

Target Lipid Model of Narcotic Toxicity

Joy McGrathDominic Di Toro

HydroQual, Inc.

SETAC North America 27th Annual MeetingMontreal, Canada

November 5-9, 2006

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Acknowledgement

Funding for this project was provided by

the Coastal Response Research Center

www.crrc.unh.edu

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Acute Toxicity QSARs for Narcotics

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Computation of Effect Concentrations

Water

* *W OW LLog(C ) 0.936log(K ) log(C ) cc

*LC = Species specific critical target lipid body burden, mol/ goctanol = mol/ glipid

cc = Chemical class adjustment, -0.352 for PAHs

*WC = Acute water-effect concentration, mmol/ L

*

* WW

C ,acuteC , chronic

ACR

Sediment

* *S OC WC ,oc K x C

g/ kgOC L/ kgOC g/ l

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Acute Effects (lethality) – Single Exposures

Water Column Sediment

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Chronic Effects (Growth, Reproduction, Mortality) – Single Exposures

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Water Column – Chronic Sublethal Effects

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90% Confidence Limits in Predicted Effect Concentration

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Water Column – Other Chronic Sublethal Effects - PAH Mixtures

Rhodes et al, 2005

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HC5 Values for Water and Sediment

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Comparison of HC5s and NOECs for PAHs

WATER SEDIMENT