Figure 2

MR Values (mean ± deviation; TA98, −S9, 2 L) of Water Samples from Plant A and Plant B from Different Periods.
MR: mutation ratio, the fold-increase over the negative control plates.
MR Values (mean ± deviation; TA98, −S9, 2 L) of Water Samples from Plant A and Plant B from Different Periods.
MR: mutation ratio, the fold-increase over the negative control plates.