Table 2: Mean concentration of heavy metals (μg/g) in Scomberomorus commerson fishes from the coast of Karachi (2006-2011).

Metals	Years	N	Muscles (Mean± SD)	Liver  (Mean± SD)	Kidney  (Mean± SD)	Gills  (Mean± SD)	Gonads  (Mean± SD)
Fe	2006-2007	61	27.09+14.67	379.88+134.10	43.03+18.92	13.73+7.13	25.21+14.26
	2007-2008	58	35.77+19.09	301.06+91.80	48.36+23.03	17.09+9.36	23.38+9.18
	2008-2009	60	24.82+18.58	469.24+126.54	47.09+28.54	27.14+18.82	24.13+15.24
	2009-2010	60	44.40+21.22	518.89+128.80	38.91+22.56	37.78+21.85	25.68+13.91
	2010-2011	55	23.71+19.59	608.93+113.22	45.13+19.88	48.31+21.12	32.21+19.14
Mn	2006-2007	61	1.41+0.72	4.35+2.03	2.14+1.02	1.50+1.10	1.71+0.82
	2007-2008	58	1.70+1.59	8.62+2.62	2.93+1.77	2.19+1.17	2.16+1.03
	2008-2009	60	1.30+1.27	8.82+2.71	2.26+2.03	3.91+1.95	2.67+1.29
	2009-2010	60	2.20+1.59	9.79+4.22	3.32+2.08	2.71+1.88	2.41+1.35
	2010-2011	55	2.01+1.66	5.35+2.55	3.66+2.48	2.92+2.17	2.63+1.90
Cu	2006-2007	61	2.78+2.33	31.20+12.89	2.69+2.50	1.59+0.76	2.46+1.78
	2007-2008	58	6.83+3.98	31.18+14.59	2.78+1.62	1.85+0.90	2.39+1.94
	2008-2009	60	6.12+2.87	32.67+17.03	3.17+2.87	2.77+1.45	2.04+1.68
	2009-2010	60	6.65+2.53	37.83+14.02	4.41+3.38	6.54+3.95	3.17+2.43
	2010-2011	55	5.52+2.39	38.57+16.62	3.93+2.80	6.98+3.78	3.64+2.31
Zn	2006-2007	61	3.17+1.96	16.46+9.90	3.02+2.73	3.74+2.45	2.76+2.11
	2007-2008	58	4.99+2.66	30.85+17.64	2.76+1.98	3.41+1.05	2.56+1.72
	2008-2009	60	8.94+4.22	43.93+20.31	3.83+2.35	2.95+1.71	3.35+2.34
	2009-2010	60	7.16+5.68	53.25+26.50	4.50+3.66	2.90+1.93	3.13+1.98
	2010-2011	55	9.43+5.76	31.33+19.23	3.75+1.63	3.14+2.88	4.14+1.88
Ni	2006-2007	61	0.16+0.12	1.61+0.66	0.26+0.18	0.33+0.21	0.58+0.16
	2007-2008	58	0.34+0.18	1.44+0.86	0.35+0.20	0.45+0.24	0.55+0.17
	2008-2009	60	1.48+0.28	2.17+0.96	0.36+0.29	0.33+0.25	0.54+0.21
	2009-2010	60	0.57+0.31	2.45+0.32	1.40+0.42	0.37+0.29	0.42+0.30
	2010-2011	55	0.62+0.41	3.22+1.13	0.46+0.32	0.32+0.20	0.36+0.28
Pb	2006-2007	61	0.14+0.12	0.41+0.22	0.16+0.10	0.21+0.16	0.28+0.12
	2007-2008	58	0.22+0.14	0.58+0.26	0.23+0.17	0.32+0.22	0.46+0.22
	2008-2009	60	0.34+0.23	1.20+0.64	0.28+0.16	0.33+0.24	0.42+0.22
	2009-2010	60	0.40+0.30	0.85+0.65	0.41+0.22	0.56+0.22	0.42+0.26
	2010-2011	55	0.54+0.37	1.01+0.94	0.33+0.20	0.49+0.23	0.63+0.37
Cd	2006-2007	61	0.19+0.06	0.54+0.16	0.36+0.24	0.46+0.28	0.32+0.21
	2007-2008	58	0.36+0.25	1.11+0.52	0.51+0.27	0.48+0.29	0.43+0.26
	2008-2009	60	0.22+0.19	1.94+0.67	0.55+0.26	0.58+0.31	0.43+0.39
	2009-2010	60	0.57+0.31	1.14+0.75	0.40+0.31	1.51+0.50	0.43+0.32
	2010-2011	55	0.68+0.42	2.03+0.91	1.22+0.68	0.56+0.21	1.18+0.46
Cr	2006-2007	61	0.17+0.08	0.78+0.39	0.42+0.26	0.26+0.10	0.24+0.15
	2007-2008	58	0.14+0.06	0.62+0.18	0.19+0.10	0.25+0.14	0.17+0.12
	2008-2009	60	0.38+0.24	1.45+0.56	0.25+0.16	0.17+0.10	0.28+0.20
	2009-2010	60	0.44+0.20	1.66+0.63	0.29+0.26	0.74+0.31	0.46+0.33
	2010-2011	55	0.51+0.22	1.93+0.87	0.42+0.21	1.34+0.64	0.43+0.24