# Can _Hediste diversicolor_ Speed Up the Breakdown of Cigarette Butts in Marine Sediments?
## 3 Results
### Physical Degradation of the CBs  
The presence of _H. diversicolor_ significantly decreased the weight of the CBs such that all the CBs, regardless of treatment (0.25 or 1 CBL\({}^{-1}\)), had a lower final weight than those CBs from the treatments without polychaetes (D-0.25 CBL\({}^{-1}\) and D-1 CBL\({}^{-1}\)) (Figure 4, Table 4). [PERSON]'s test clearly shows two homogeneous groups: one formed by the two concentrations of CBs without polychaetes and another by the two concentrations with polychaetes (\(p<0.05\)). On the contrary, the temperature did not affect the final weight of the CBs, nor was there any interaction between this factor and the CBs (Table 4). According to our classification of the different degradation states, the physical degradation of CB was significantly increased by polychaetes (Table 4). Therefore, 100% of the CBs of any treatment with _H. diversicolor_ lacked both the paper coating and the plug wrap. In non-polychaete treatments, 66% of CBs still had all or most of the paper coating at 15 \({}^{\circ}\)C, while at 23 \({}^{\circ}\)C, 80% of the butts had the coating paper partially removed, and only 20% still had it. Despite this difference, there were no significant differences in the CB degradation \begin{table}
\begin{tabular}{l l l l l l} \hline  & & **df** & **SS** & **MS** & **F** & \(\mathbf{p}\) \\ \hline \multirow{4}{*}{Weigth loss} & CB & 3 & 16,426.65 & 5475.55 & 6.26 & 0.0001 \\  & Temperature & 1 & 450.76 & 450.76 & 1.137 & 0.248 \\  & CB \(\times\) Temperature & 3 & 597.90 & 199.30 & 1.137 & 0.298 \\  & Error & 22 & 8719.28 & 396.33 & - & \\  & Total & 30 & 26,412.62 & - & - & \\ \hline \multirow{4}{*}{Degradation level} & CB & 3 & 24.53 & 8.18 & 38.55 & 0.0001 \\  & Temperature & 1 & 0.19 & 0.19 & 0.89 & 0.345 \\ \cline{1-1}  & CB \(\times\) Temperature & 3 & 0.53 & 0.17 & 0.38 & 0.487 \\ \cline{1-1}  & Error & 22 & 4.67 & 0.21 & & \\ \cline{1-1}  & Total & 30 & 350 & & & \\ \hline \end{tabular}
\end{table} 
Table 4: Results of two-factor ANOVAs for the CB weight loss and degradation level at the different CB concentrations (0 CBL\({}^{-1}\), 0.25 CBL\({}^{-1}\), 1 CBL\({}^{-1}\) with _Hédiste diversicolor_, and 0.25 CBL\({}^{-1}\), 1 CBL\({}^{-1}\) without polychaetes), and at the two temperatures studied (15 \({}^{\circ}\)C, 23 \({}^{\circ}\)C) after 28 days. Sum square (SS); mean square (MS); degrees of freedom (df); ns = nonsignificant. Figure 4: Weight (g; maximum, mean, and minimum) of the CBs without _Hédiste diversicolor_ (**left**) and with these polychaetes (**right**) exposed to two different CB concentrations: 0.25 CBL\({}^{-1}\), 1 CBL\({}^{-1}\) and at the two temperatures studied: 15 \({}^{\circ}\)C (blue dots), 23 \({}^{\circ}\)C (red dots) for 28 days. level in the non-polychaete treatments with respect to temperature, nor was there any interaction between temperature and the treatments (Table 4). Cellulose acetate degraded an average of 0.53 \(\pm\) 0.33% in those treatments without _Hediste_, and 1.46 \(\pm\) 0.91% with _Hediste_, without statistically significant differences between both means (\(p\) = 0.346) (Figure 5A). The treatments carried out at 15 \({}^{\circ}\)C showed an average percentage of 1.45 \(\pm\) 0.91% in the degradation of CA, and those carried out at 23 \({}^{\circ}\)C having an average of 0.54 \(\pm\) 0.34%, without statistically significant differences between the two (\(p\) = 0.356) (Figure 5B). There were also no statistically significant differences in CA degradation between the 0.25 CBL\({}^{-1}\) (1.02 \(\pm\) 0.85%) and 0.50 CBL\({}^{-1}\) (0.97 \(\pm\) 0.28%) treatments (\(p\) = 0.960). The highest percentage of CA degradation was seen in those treated with CB at 15 \({}^{\circ}\)C (2.58 \(\pm\) 1.72%), and the lowest percentage was for the treatment without polychaetes at 15 \({}^{\circ}\)C (0.32 \(\pm\) 0.36%).