Table 1. Mass Balance of Total Fluorine for Eight Products Analyzed by PIGE and Targeted Analysis of Extracts before and after Storage for 2 Years, and after Hydrolysis Assaya.
| Sample name | Burrito molded bowl 1 | Burrito molded bowl 2 | Salad molded bowl 3 | Donut paper bag 4 | Pastry paper bag 5 | Pastry paper bag 6 | Popcorn paper bag 7 | Popcorn paper bag 8 |
|---|---|---|---|---|---|---|---|---|
| PIGE | ||||||||
| Concentration | 1 300 000 | 1 010 000 | 1 180 000 | 30 100 | 23 800 | 28 000 | 11 400 | <LOQ |
| Original Targeted Analysis | ||||||||
| Concentration (original extraction) | 283 | 569 | 328 | 181 | 105 | 126 | 109 | 4.07 |
| Percent of PIGE concentration explained (%) | 0.02 | 0.06 | 0.03 | 0.60 | 0.44 | 0.45 | 0.96 | N/A |
| Concentration (re-extraction after 2 years) | 395 | 552 | 340 | 31.1 | 31.0 | 24.3 | 45.4 | 9.30 |
| Percent of PIGE concentration explained (%) | 0.03 | 0.05 | 0.03 | 0.10 | 0.13 | 0.09 | 0.40 | N/A |
| Hydrolysis | ||||||||
| Concentration | 36 100 | 24 100 | 65 700 | 3900 | 8100 | 8000 | 2900 | 7.00 |
| Difference between hydrolysis and concentration (re-extraction after 2 years) | 35 700 | 23 700 | 65 400 | 3860 | 8000 | 7960 | 2860 | |
| Percent of PIGE concentration explained (%) (F from unknown precursors released after hydrolysis) | 2.8 | 2.4 | 5.6 | 13 | 34 | 28 | 25 | N/A |
a
Concentrations of total F analyzed by PIGE and targeted analysis of extracts and after hydrolysis are expressed in μg F/m2. Also included are percentage contributions of the targeted analysis to total F measured by PIGE. The detailed information on conversion for concentration of total F (μg F/m2) from concentration of PFAS (ng/g) for targeted analysis of extracts and after hydrolysis was shown in Section S9. N/A indicates not applicable.