Figure 6.

Yeast RNA degradation in the presence of 0.125 m²/L coal particle loadings (25 to 107 μg/mL depending on surface area). Coal samples of varying pyritic sulfur content were exposed to 1.5 mg/L RNA, which was quantified using fluorescence of RiboGreen dye. Dissolved iron concentrations were measured at the end of the experiment (i.e., 7 hours) and are listed in Table 1. At the end of the experiment the pH of the RNA solution was 5.64; the pH of coal samples ranged from 5.00 to 5.52; and the pH of the pyrite sample was 4.87. Previous studies with yeast RNA exposed to pyrite have shown that the apparent RNA degradation is not due to a reduction in pH of solution.