Little Akaki River sediment enrichment with heavy metals, pollution load and potential ecological risks in downstream, Central Ethiopia

Environmental Systems Research

Table 7 Concentrations of metals in Little Akaki River sediment (mg/kg) and SQGs values

Metal	Overall mean concentration of elements in LAR sediment (mg/kg)	USEPA (2002)		CCME (2001)
Metal		CB-TEC^a (mg/kg)	CB-PEC^b (mg/kg)	ISQGs^c (mg/kg)	PEC^d (mg/kg)
Zn	148.28	121	459	123	315
Cr	109.51	43.4	111	37.3	90
Pb	129.68	35.8	128	35.0	91.3
Cd	3.14	0.99	4.98	0.6	3.5

^aConsensus based threshold effect concentration (CB-TEC) (USEPA 2002); ^bConsensus based –probable effect concentration (CB-PEL) of (USEPA 2002); ^cInterim Sediment Quality Guidelines (ISQGs) of (CCME 2001); ^dProbable effects concentration (PEC) of (CCME 2001)