Ecotoxicological Effects of Metal Jigheads Used in Recreational Fishing on the Benthic Amphipod Hyalella azteca

ABSTRACT

Lost fishing gear can negatively affect freshwater ecosystems due to the variety of potentially harmful materials. Many fishing tackle items used for recreational angling such as hooks and sinkers contain lead as a high‐density metal, which is known for negative effects on the environment. Alternatives that are labelled as “lead‐free” and “environmentally friendly” are becoming more popular and used more frequently, but comparative studies on their metal composition and assessments of their ecotoxicology and environmental safety are scarce. In this study, three alternative jighead types were evaluated with respect to their release of metal ions, and to assess their aquatic toxicity potential on the benthic amphipod Hyalella azteca . In contrast to the expectation, “lead‐free” labelled products were found to contain lead and other harmful metals such as copper, nickel, zinc, and antimony. For 14 days aqueous exposure to leachates of all three jighead types, significant acute mortality ranging between 52% and 100% was observed. The analytical comparison of metal compositions in the leachates and the classification of jighead type specific metal profiles by PCA identified that the toxic effects are mostly linked to an interaction of elevated lead, antimony, and zinc concentrations. The results of this study demonstrate that lost or discarded jigheads are a potential stressor in freshwater ecosystems, and that consumers cannot automatically trust in environmental advantages of alternative fishing tackle products that claim to be “lead‐free” or “environmentally friendly”.