Report on the Levels of Cadmium,
Lead, and Mercury in Imported
Rice Grain Samples
Biological & Medical Research Department (MBC#03),
King Faisal Specialist Hospital & Research Centre,
P.O. Box 3354, Riyadh 11211, Saudi Arabia
Received September 3, 2000; Accepted January 2, 2001
In an attempt to know whether highly consumed food might
contribute to metal exposure, we analyzed cadmium, lead, and mer-
cury in 27 rice grain samples commonly consumed in Saudi Arabia by
atomic absorption spectrometry after acid digestion. The mean con-
centrations and ranges of cadmium, lead, and mercury in tested rice
samples were 20.261 (range <DL–178.026 µg/kg), 134.819 (range
23.1–1529.0 µg/kg), and 3.186 (range <DL–43.573 µg/kg), respec-
tively. The results showed high concentrations of metals and in some
cases exceeded the Provisional Tolerance Weekly Intake (PTWI) rec-
ommended by FAO/WHO. It was also noted that different rice grain
samples had varying concentrations of these metals. Because the bulk
of literature warns against the cumulative effects of prolonged heavy
metal exposure, regular consumption of rice by local populations
might pose potential health problems.
Index Entries: Cadmium; lead; mercury; rice; atomic absorption
spectrophotometer; vapour generator accessory.
Metals and their compounds are introduced into our environment
both from natural and anthropogenic sources. Although some metals are
natural constituents of soils, a number of toxic metals such as cadmium,
lead, and mercury may also contaminate the soils as a result of human
© Copyright 2001 by Humana Press Inc.
All rights of any nature, whatsoever, reserved.
*Author to whom all correspondence and reprint requests should be addressed.
Biological Trace Element Research
Vol. 83, 2001