Determination of manganese in some environmental water samples.

Sample		Manganese/μg L−1		Recovery ± s (%)	s r b (%)
		Added	Founda (n = 5)
Tap water		0, 10, 50	55.0, 65.0, 108.0	100.0 ± 0.0, 103.0 ± 0.5	0.00, 0.25
Well water		0, 10, 50	35.0, 45.0, 85.0	100 ± 0.0, 100 ± 0.0	0.00, 0.00
River water	Karnaphully (upper)	0, 10, 50	75.0, 88.0, 125.0	104.0 ± 06, 100.0 ± 0.0	0.35, 0.00
	Karnaphully (lower)	0, 10, 50	80.5, 90.0, 135.0	99.5 ± 0.5, 103.0 ± 0.8	0.21, 0.39
	Halda (upper)	0, 10, 50	45.0, 55.0, 98.0	100.0 ± 0.00, 103.0 ± 0.6	0.00, 0.29
	Halda (lower)	0, 10, 50	53.0, 65.0, 105.0	103.0 ± 0.8, 102.0 ± 0.5	0.36, 0.33
Sea water	Bay of Bengal (upper)	0, 10, 50	25.0, 35.0, 80.0	100.0 ± 0.0, 106.0 ± 1.0	0.00, 0.45
	Bay of Bengal (lower)	0, 10, 50	35.0, 45.0, 90.0	100.0 ± 0.0, 105.8 ± 1.0	0.00, 0.38
Drain water	T. S. P. Complexc	0, 100, 500	130.0, 235.0, 630.0	102.0 ± 0.8, 100.2 ± 0.0	0.18, 0.00
	PHPd	0, 100, 500	160.0, 260.0, 665.0	100.0 ± 0.0, 100.7 ± 0.5	0.00, 0.25
	BSRMe	0, 100, 500	245.0, 350.0, 750.0	101.0 ± 0.8, 100.6 ± 1.0	0.29, 0.35
	K. P. M. waterf	0, 100, 500	188.0, 288.0, 690.0	100.0 ± 0.8, 100.2 ± 0.5	0.00, 0.42
	Berger paintsg	0, 100, 500	270.0, 370.0, 775.0	100.0 ± 0.0, 100.6 ± 1.2	0.00, 0.55

^aAverage of five replicate determinations of each sample.

^bThe measure precision is the relative standard deviation(s_r).

^cT. S. P. Complex Ltd., Patenga, Chittagong.

^dPHP Glass factory, Chittagong.

^eBangladesh Steel Re-rolling Mills Ltd. (BSRM), Baizid Bosthami, Chittagong.

^fKarnaphuly Paper Mills, Chandraghona, Chittagong.

^gBerger Paints Bangladesh Limited, Kalurghat, Chittagong.