As a dynamic economic hub of central region of Vietnam, Da Nang has experienced several years of rapid urbanization and industrialization. But this impressive growth fails to hide the realities of environmental quality degradation, of which heavy metal contamination has been widely recognized as a risk to human and ecological health. This paper provides an overall assessment of Pb and Cd contaminations by sediments and bivalves from two estuaries of Da Nang city in the period of 5 years from 2008 to 2012. The pooled values of Pb and Cd contents in sediments from Han and Cu De estuaries, based on Canadian guidelines, indicated that adverse biological effect might be occasionally provoked in both estuaries, in which Han estuary showed more severe contamination. In addition, excess of Pb and Cd contents was detected in bivalve samples from Han estuary, compared to the permissible limits recommended by Vietnamese Ministry of Health (QCVN 8-1:2011/BYT) whereas lower corresponding values were observed in samples from Cu De estuary but still showed potential risks, suggesting an alarm to dwellers in terms of food consumption. The findings suggested that species Corbicula sp., Crassostrea gigas Th. and Perna viridis L.; and Ostrea rivularis G. may be used as bioindicators for Pb and Cd contamination monitoring in the estuarial environment, respectively.

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