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The metal profiles in sediments of the Daya Bay (DYB) in China were established using sequential extraction protocols proposed by the European Community Bureau of Reference (BCR). The surface sediment samples from 23 representative stations were collected in 2011 and were analysed to evaluate the mobility and bioavailability of a suite of potentially toxic metals (Cr, Cu, Ni, Zn, Pb and Cd) and metalloid (As). The obtained ranking order of migration and transformation, and the degree of pollution was Pb > Cd > Cu > Zn > Ni > Cr > As. Among these elements, Pb is considered to pose a serious threat to human health and ecological environment due to its significant percentage in non-residual form. The ratios of secondary and primary phases showed that studied sediments are moderately to heavily polluted with Cu and Zn, and Cd and Pb respectively. The levels of association between the variables (metal-metalloid) at each step of sequential extractions were evaluated with multivariate statistical analysis, including correlation analysis and principal components analysis. With these analyses, the possible sources of potential pollution were deduced. The correlation analysis revealed that Total Organic Carbon content is the most important influencing factor affecting the distribution of potentially toxic elements in Daya Bay. The principal components analysis (PCA) suggested that the studied elements in DYB area originate primarily from natural weathering and secondly from industrial wastewater and aquaculture waste water., Profili metala u sedimentima zaljeva Daya (DYB) u Kini određeni su sekvencijskom ekstrakcijom prema proceduri koju je izradio European Community Bureau of Reference. Da bi se odredili pokretljivost i biodostupnost otrovnih metala (Cr, Cu, Ni, Zn, Pb i Cd) i polumetala (As), 2011. godine prikupljeni su i analizirani uzorci površinskog sedimenta s 23 reprezentativne lokacije. Pronađen je sljedeći redoslijed migracija, transformacija te stupnja zagađenja: Pb > Cd > Cu > Zn > Ni > Cr > As. Smatra se da među tim elementima olovo predstavlja ozbiljnu prijetnju za ljudsko zdravlje i okoliš zbog znatnog udjela nerezidualnih oblika. Omjer primarne i sekundarne faze pokazuje da su proučavani sedimenti umjereno do jako onečišćeni bakrom i cinkom, također kadmijem i olovom. Povezanost varijabli (metala i polumetala) na svakom koraku uzastopnih ekstrakcija procijenjena je multivarijatnom analizom, uključujući i korelacijsku analizu i analizu glavnih komponenata. Zahvaljujući tim analizama, utvrđen je moguć izvor zagađenja. Korelacijska analiza pokazala je da je sadržaj ukupnog organskog ugljika najvažniji faktor koji utječe na raspodjelu otrovnih elemenata u zaljevu Daya. Analiza glavnih komponenata (PCA) pokazala je da proučavani elementi u području DYB-a potječu uglavnom od prirodnog trošenja stijena, potom i iz industrijskih otpadnih voda i otpadnih voda akvakulture.