Heavy Metals Pollution and Pb Isotopic Signatures in Surface Sediments Collected from Bohai Bay, North China

Table 1

Heavy metal concentrations in surface sediments of Bohai Bay and other Bays in China (mg/kg).

Station	Cr	Ni	Cu	Zn	Cd	Pb	References
Minimum	51.32	21.88	16.84	45.31	0.11	20.69	This study
Maximum	94.33	47.04	34.99	84.19	0.18	28.33
Mean	79.73	36.56	28.70	72.83	0.15	25.63
Variable coefficient (%)	11.39	13.84	12.71	12.04	10.29	7.25
Intertidal Bohai Bay, China	68.6	28.0	24.0	73.0	0.12	25.6	[5]
Southern Bohai Bay, China	33.5	30.5	22.7	71.7	0.14	21.7	[9]
Western Bohai Bay, China	53.1	31.4	27.9	83.6	0.13	20.5	[8]
Upper continental crust	35	20	25	71	0.098	16.6	[12]
Yangtze Estuary, China	78.9	31.8	30.7	94.3	0.26	27.3	[18]
Pearl River Estuary, China	89.0	41.7	46.2	150	n.d.	59.3	[19]
Marine sediment quality I	80	n.d.	35	150	0.5	60	[20]
Marine sediment quality II	150	n.d.	100	350	1.5	130	[20]
Target*	25	20	20	75	0.4	35	[13]
Trigger*	50	35	55	150	1.0	65	[13]
Action*	80	40	65	200	1.5	75	[13]

∗Target indicates the desired quality for fairly clean sediment that is close to background levels.
Trigger indicates that the sediment is moderately contaminated.
Action indicates heavily polluted sediments.