Peroxide Value (meq O₂/kg) Mean (SD)

Months

Glass

PET

HDPE

PLA

0

7.63 (0.47)^*

7.63 (0.47)^●,●●

7.63 (0.47)^{#, ##}

7.63 (0.47)^♦,♦♦

3

8.17 (0.29)^a,b**

11.66 (0.57)^b●●

14.12 (0.69)^a,b##

11.47 (0.45)^a♦♦

5

12.63 (1.47)^*,**

12.86 (1.06)^●

13.94 (1.22)^#

12.87 (1.95)^♦

7

15.67 (0.55)^c*,**

15.27 (0.55)^{d,e●,●●}

17.88 (1.02)^c,d#,##

17.32 (0.52)^e♦,♦♦

9

29.16 (0.76)^f*,**

29.23 (0.68)^g●,●●

38.68 (0.91)^f,g#,##

32.33 (0.58)^{f,g♦,♦♦}