Biomarkers of pollution effects in the bivalves Mytilus edulis and Macoma balthica collected from the southern coast of Finland (Baltic Sea)

Abstract

ABSTRACT: Levels of selected biomarkers in 2 bivalve species, the hard-bottom filter-feeder Mytilusedulis and the infaunal deposit/suspension-feeder Macoma balthica were measured in 2 areas (Tvar-minne and Turku Archipelago) in the southern coast of Finland. The bivalves were collected for themeasurement of acetylcholinesterase (AChE), glutathione-S-transferase (GST) and catalase (CAT)activities, and for the determination of metallothionein (MT) content. The content of organochlorines(8 PCB congeners, DDE, DDD, DDT, HCH, HCB, dieldrin) and selected heavy metals (Cd, Cu, Hg,Zn) were measured in the soft tissues. In M. balthica collected from the Turku Archipelago region,biomarker gradients were observed in MT, GST and CAT, mostly coinciding with the tissue concen-trations of total PCBs, DDTs and selected metals. In M. edulis the biomarker responses were less con-sistent with regard to tissue pollutant concentrations. In the Tvarminne region no marked biomarkergradients were observed. The levels of all biomarkers varied significantly between the two species.The integrated biomarker response (IBR) index showed good accordance with the observed high tis-sue levels of organochlorines at the northern Airisto station in both species. This study is the first ofits kind performed in the coastal waters of Finland, and the results clearly demonstrate the usefulnessof the multibiomarker approach. Moreover, the use of 2 sessile species with markedly differing feed-ing modes and living habitats is considered a rational strategy for assessing the pollution status ofcoastal sea areas.KEY WORDS: Biomarkers · Baltic Sea · Bivalves ·