Influence of environmental conditions on the toxicokinetics of cadmium in the marine copepod Acartia tonsa

Maria D. Pavlaki*, Rui G. Morgado, Cornelis A.M. van Gestel, Ricardo Calado, Amadeu M.V.M. Soares, Susana Loureiro

*Corresponding author for this work

    Research output: Contribution to JournalArticleAcademicpeer-review

    Abstract

    mMarine and estuarine ecosystems are highly productive areas that often act as a final sink for several pollutants, such as cadmium. Environmental conditions in these habitats can affect metal speciation, as well as its uptake and depuration by living organisms. The aim of this study was to assess cadmium uptake and depuration rates in the euryhaline calanoid copepod Acartia tonsa under different pH, salinity and temperature conditions. Cadmium speciation did not vary with changing pH or temperature, but varied with salinity. Free Cd2+ ion activity increased with decreasing salinities resulting in increased cadmium concentrations in A. tonsa. However, uptake rate, derived using free Cd2+ ion activity, showed no significant differences at different salinities indicating a simultaneous combined effect of Cd2+ speciation and metabolic rates for osmoregulation. Cadmium concentration in A. tonsa and uptake rate increased with increasing pH, showing a peak at the intermediate pH of 7.5, while depuration rate fluctuated, thus suggesting that both parameters are mediated by metabolic processes (to maintain homeostasis at pH levels lower than normal) and ion competition at membrane binding sites. Cadmium concentration in A. tonsa, uptake and depuration rates increased with increasing temperature, a trend that can be attributed to an increase in metabolic energy demand at higher temperatures. The present study shows that cadmium uptake and depuration rates in the marine copepod A. tonsa is mostly affected by biological processes, mainly driven by metabolic mechanisms, and to a lesser extent by metal speciation in the exposure medium.

    Original languageEnglish
    Pages (from-to)142-149
    Number of pages8
    JournalEcotoxicology and Environmental Safety
    Volume145
    Early online date18 Jul 2017
    DOIs
    Publication statusPublished - Nov 2017

    Keywords

    • Abiotic factors
    • Bioconcentration
    • Chemical speciation
    • Depuration rate
    • Metal
    • Uptake rate

    Fingerprint

    Dive into the research topics of 'Influence of environmental conditions on the toxicokinetics of cadmium in the marine copepod Acartia tonsa'. Together they form a unique fingerprint.

    Cite this