Hecht, S., and B.L. Boese. 2002. Sensitivity of an infaunal amphipod, Eohaustorius estuarius, to acute waterborne exposures of 4-nonylphenol: Evidence of a toxic hangover. Environ. Toxicol. Chem. 21(4)816-819. WED-01-083
Three independent trials were conducted using mortality and burial as endpoints. Mean LC50 was 227 ug/l. One hour burial as a sub-lethal endpoint increased the sensitivity of the toxicity test by 40%; however most amphipods that survived exposure were able to recover within 24-48 hours. This "toxic-hangover" was dose-dependent.