Soluble Elements


Soluble Elements

Solubles: Al, B, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Pb, S, Si, Zn (Other elements are available. Contact the lab.)

Quantitative determination by ICP-AES.


This method quantitatively determines the concentration of the listed elements in water samples by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). Contact the lab if lower detection limits or elements not listed in the table are needed. Difficult matrices may result in higher MDLs than those listed.

Element MDL (mg/L)
Al 0.05
B 0.01
Ca* 0.1
Cd 0.005
Cr 0.005
Cu 0.010
Fe 0.010
K 0.05
Mg* 0.1
Mn 0.005
Mo 0.005
Na* 0.1
Ni 0.005
P 0.05
Pb 0.010
S** 0.1
Si 0.01
Zn 0.005

* Note: Ca, Mg and Na are reported in meq/L units unless mg/L units are requested on the work request form. To convert results in meq/L units to mg/L units multiply Ca results by 20, Mg results by 12.15 and Na results by 23.

** Note: Sulfur is reported as SO4-S (soluble S) assuming that all sulfur present is in the sulfate form. If sulfate is of specific interest, the ion chromatographic method (SOP 880) should be requested.

The EPA recommends that water for soluble analytes be filtered and acidified at the time of collection. Samples should be filtered through 0.45 uM filters and acidified to pH < 2 with 1+1 HNO3 as soon after collection as possible. If other analyses such as pH, EC, nitrate, etc. are required, a second work request form must be used for the non-treated samples. Samples submitted without the noted preservation will be tested as received unless in-lab filtration and/or acidification are requested on the work request form.

Sample amount requested: 50 mL (for any single test and for most combinations of tests)

Questions concerning limited sample size can be answered by the UC Davis Analytical Laboratory.

U.S. EPA Method 200.7, Trace Elements in Water, Solids, and Biosolids by Inductively Coupled Plasma-Atomic Emission Spectrometry