Table 2.

Comparison of the concentrations of heavy metals in the study area with values from the literature (unit: mg/kg).

Study Area	Cu	Pb	Zn	Cd	Cr	References
Eastern Beibu Gulf	16.37	32.23	93.12	0.08	35.51	This study
Beibu Gulf	-	36.22	-	0.12	-	[25]
Beibu Gulf	27.07	46.56	73.6	0.16	59.50	[39]
Coastal sea area, Guangxi Province, China	18.3	19	-	0.025	-	[30]
Pearl River Estuary, China	46.8	47.9	140	-	87.6	[31]
Pearl River, South China	348.0	102.6	383.4	1.72	93.1	[32]
Victoria Harbour	45.2–3789.5	47.4–138.1	97.9–610.4	2.61–3.33	57.5–601.2	[33]
Taranto Gulf	47.4	57.8	102.3	-	85.9	[34]
Puerto Rico	106	11	-	0.13	55	[35]
Leizhou Bay	4.51–30.5	8.94–32.2	-	0.18–0.67	-	[37]
	22	21.9	60.4	0.12	60	[38]
Thermaikos Gulf	80	77	184	-	47	[35]
Primary standard criteria	35.0	60.0	150.0	0.5	80	a

“-”: not available; “a”: values from national standard GB 18668-2002 (CSBTS, 2002).