Two sample treatment methods are evaluated to provide accurate boron determ
ination at low concentrations in biological and botanical samples. The firs
t approach is a hot 1M nitric acid extraction of baron from the sample The
second technique uses wet digestion with concentrated sulfuric acid. The ac
curacy of the procedures was demonstrated with botanical and animal referen
ce materials (Corn Bran RM 8433 and Whole Egg Powder RM 8415). At least thr
ee results are given for each reference material. Two are direct measuremen
ts of B using independent B-10 and B-11 calibration curves with a Be intern
al reference, and the third is obtained by isotope dilution mass spectromet
ry (IDMS). The B-10 and B-11 values are consistent for both acid treatment
procedures. The IDMS results also are consistent. Overall results for Whole
Egg Powder and Corn Bran RM's match the best-estimate values within their
confidence intervals. These results demonstrate the ability to measure B ac
curately at the 0.3 mu g/g concentration range Thus, low-level B samples ca
n be analyzed with accuracy and precision by the two approaches. These meth
ods introduce very little dissolved organic carbon (DOC) in the final solut
ion and allow the use of large (2 g) sample aliquots. Direct introduction o
f biological fluids including whole blood serum also was evaluated critical
ly for the determination of B.