Evaluation of an Inter-laboratory Comparison for Inorganic

Compounds Analysis in Soils
Shigeru Suzuki*, Akiko Kida*, Shin-ichi Sakai* and Masatoshi Morita**
* The National Institute for Environmental Studies Research Center
for Material Cycles and Waste Management
** The National Institute for Environmental Studies Research Center
+ Correspondence should be addressed to Shigeru Suzuki:
The National Institute for Environmental Studies Research Center
for Material Cycles and Waste Management
(16-2 Onogawa, Tsukuba, Ibaraki, 305-8506 Japan)

Abstract
An Inter-laboratory comparison of seven inorganic compounds, namely chromium(VI), mercury, lead, cadmium, arsenic, boron and fluorine, in three contaminated soils and two waste samples was presented. The analytical method was based on newly published compliance test for contaminated soils. Nineteen laboratories were included in the study. The standard deviations of chromium(VI), lead and cadmium in soils were relatively small and ranged from 10 to 20 percent. The standard deviations of arsenic, boron and fluorine in soils were approximately 30 percent; from 30 to 80 per-
cent; and 30 percent respectively. The standard deviations of lead and arsenic in waste samples were higher than those in soils. The valiabilities in higher concentration samples were mostly the same as in the lower ones.

Key words: Inter-laboratory Comparison, inorganic compounds, soil, compliance test, standard deviations