DI-extracted PBC Inc samples were prepared using on
ly a chlorate internal standard. Each sample consi
sted of
0.9 mL soil extract and 0.1 mL 350 ppm chlorate sta
ndard. These samples were analyzed by the MS proce
dure
described above using instrument specifications as
listed in Table 2. The peak areas of these samples
were then compared to the (peak area) to (P concentration) ra
tio of the reference sample (SA6 or SA11) in order
to determine
concentrations of P.