Background pollution and anthropogenic impact of Cr in Jiaozhou Bay 1989

Chromium (Cr) pollution in marine environmental is one of the critical environmental issues in the whole world. Understanding the background pollution and source of Cr in marine bay is essential to pollution control and environmental remediation. Jiaozhou Bay is a semi-closed bay located in Shandong Province, China. This paper analyzed the background pollution and source of Cr in surface waters in Jiaozhou Bay in April and July 1989. Results showed that Cr contents in April and July were 1.01-3.29 μg L −1 and 0.63-2.36 μg L −1 , respectively. These contents were much lower than the Grade I (50 μg L −1 ) for Cr in Sea Water Quality Standard (GB 3097-1997). The pollution level of Cr in Jiaozhou Bay in 1989 was very slight, and the background pollution level of Cr could be considered as 0.63-3.29 μg L −1 . The major anthropogenic sources of Cr were atmosphere deposition and river discharge, whose source strengths were 3.29 μg L −1 and 2.36 μg L −1 , respectively. In general, the background pollution of Cr was very slight in Jiaozhou Bay in 1989 and the influence of human activities was still light.