Variation in toxicity of copper pyrithione among populations and families of the barnacle, Balanus amphitrite

Abstract

Inter- and intra-population variation in the toxicity of the antifouling biocide copper pyrithione (CuPT) was examined for nauplius larvae of the barnacle Balanus amphitrite. Nauplii were collected from brooding adults from four sites within the Newport River estuary (NC), chosen based on an initial estimation of recent and historical human activities that affect local contamination levels. Each site was characterized for the presence of polycyclic aromatic hydrocarbons and for the frequency of gastropod imposex, an indicator of contamination by organotins. Sensitivity of nauplii to CuPT varied significantly across the sites/populations, with LC₅₀ values ranging from 4.0 μg l⁻¹ to 6.1 μg l⁻¹. Larvae from the most contaminated site were the most sensitive to CuPT. Intrapopulation variation in toxicity was investigated by exposing nauplius larvae from 15 maternal families to a fixed concentration of CuPT (6.1 μg l⁻¹). Variation in larval mortality among the families was significant, ranging from 15.1% to 98.9%.

Keywords:

• copper pyrithione
• Balanus amphitrite
• toxicity
• interpopulation variation
• intrapopulation variation

Acknowledgments

This research was funded by the Naval Research Enterprise Internship Program (JAR), the NOAA National Estuarine Research Reserve Graduate Research Fellowship Program (Grant # NA04N0S4200151 to JAR/PMG), and the Office of Naval Research (DR, ERH). J. Osterberg produced Figure 1.