Use of Tisbe biminiensis nauplii in ecotoxicological tests and geochemical analyses to assess the sediment quality of a tropical urban estuary in northeastern Brazil

An approach pooling geochemical analyses and ecotoxicological tests has been applied to assess the sediment quality of the Capibaribe River Estuary, Brazil. Toxicity tests were performed to compare a well-established, labor-intensive protocol using ovigerous females to a new, easier and faster protocol using nauplii of the epibenthic marine copepod Tisbe biminiensis. The endpoints of the nauplii toxicity test were comparable to those of the female test. Nauplii proved to be more sensitive than females as a biological model for indicating sediment toxicity. All sediments collected had at least one contaminant above the threshold effects level (TEL) proposed in the literature. Furthermore, more than one-third of samples exhibited contaminants above the probable effects level (PEL). The PCA revealed that nauplii mortality was associated with metals in October 2014, which was confirmed by the Spearman correlation factor. In contrast, no strong association among contaminants and toxicological endpoints in May 2015 was found. [Display omitted] •A new protocol has been established for assessing sediment toxicity.•Nauplius of Tisbe biminiensis is more sensitive to xenobiotics than adult female.•Endpoints of the nauplii test were strongly correlated with toxic chemicals.•Sediments of the Capibaribe estuary are impacted by PAHs, organochlorines and metals.