Oceanologia (Mar 2005)
Recent trends in the prevalence of neoplasia in the Baltic clam <i> Macoma balthica</i> (L.) from the Gulf of Gdañsk (Baltic Sea)
Abstract
This study discusses the occurrence of neoplasia in the Balticclam Macoma balthica from the Gulf of Gdańsk in recent yearsand investigates potential relationships between toxic compoundsin the environment and the presence of the cancer. The diseasewas identified at four sampling stations during 1999-2002. Comparison withprevious results highlighted the substantialprevalence of the tumour between 1998 and 2002. The prevalenceof the cancer was strongly dependent on the sampling location(p > 0.001): it was highest at sampling point H45 (the deepestpart of the gulf) and lowest at station PB30 (central part ofthe gulf). Monthly studies showed a trend towards an increasingprevalence of neoplasia during the warm months. However, overseveral sampling months no strong statistical correlation betweenthe prevalence of the disease and the sampling time was found.The results of the study suggest that several environmental factorsmay promote the progress of the cancer in M. balthica from the Gulf of Gdańsk: it is most probably an indirecteffect of pollution, although causality cannot be proven at thisstage. Seriously polluted and exhibiting a considerable asymmetryof contamination, the ecosystem of the gulf provides an idealenvironment for testing potential cause-effect relationshipsbetween pollutants and their biological effects.
