## 4 Conclusions  
The results of our chemical analysis from 35 porewater samples showed that the PAHs napphthhalene, acenaphthalene, benzo(b)fluoranthene, dibenz(a,h)anthracene, and the metal cadmium were not detected at all ampling stations, and the detection frequency of the other 22 compounds, ranging from high to low, was fluoranthene (94.29%), pyrene (91.43%), and zinc (88.57%). The mortality rate of _H. azteca_ exposed to 11 sampling stations (DB1, DB2, SY1, SY2, SY3, HJ7, LK1, LK3, WR1, WR3, and WR6) was 100% at the end of the porewater toxicity test, and the survival rate was not significantly correlated with the  
Figure 10: Diagram of the correlation of interstitial water toxic units and zebrafish embryo survival rate. Figure 9: Diagram of the correlation of interstitial water benchmark units and zebrafish embryo survival rate. 6 trace metals and 16 PAHs. In addition, 100% mortality in the zebrafish embryo toxicity tests was not only observed at the previous 11 sites but also at the other 12 sampling sites (YSI, YS2, YS3, YS4, DB3, DB4, DB5, HJ2, LK2, WR2, WR4, and WR5). This indicates that the porewater of these 11 sites was toxic for both test organisms, and zebrafish embryos were more sensitive than the amphibod _H. azteca_. Based on the experimental results, the samples show a lack of acute mortality and can also significantly reduce the heartbeat rate of zebrafish embryos. Therefore, it is concluded that the hatching rate of zebrafish embryos provided a more sensitive endpoint than mortality and deformity rate. These results also indicate that the cardiac functioning and circulatory system of fish embryos decreased in a moderate or even low toxic environment. Therefore, it is concluded that the index of heart rate is more sensitive than mortality, and deformity rates of early larvae towards polluted porewater areas of sediments can be affected to some extent. Pearson correlation analysis showed that the concentration of acenaphthene, fluorene, and anthracene had a significant positive correlation with zebrafish embryo survival rate (\(p<0.05\)), the heart rate had a significant positive correlation only with fluorene and anthracene (\(p<0.001\)), and the deformity rate had a significant positive correlation with anthracene (\(p<0.05\)). The chemical analysis and toxicological approach provide a preliminary understanding of the possible risks of dissolved metals and PAHs in sediment porewaters collected from different regions of Taiwan. The following materials are available online at [[https://www.mdpi.com/article/10.3390/app11178021/s1](https://www.mdpi.com/article/10.3390/app11178021/s1)]([https://www.mdpi.com/article/10.3390/app11178021/s1](https://www.mdpi.com/article/10.3390/app11178021/s1)), Table S1. Mobile phase gradient for the UPLC. Table S2. Wavelength programs for fluoreference detection. Table S3. Retention times and method detection limits of the 16 PAHs. Figure S1: Effects of deformities caused by sediment porewater from different locations in Taiwan on zebrafish after 2 days of treatment. The main deformities include spinal cord curvature, cardiac edema, developmental stagnation, tail necrosis. Figure S2: Effects of deformities caused by sediment porewater in different locations in Taiwan on zebrafish after 3 days of treatment. The main deformities include all the above. Conceptualization, S.-Y.H. and [PERSON]-[PERSON]; formal analysis, C.-H.L. ; software, M.-C.W. ; investigation, Y.-H.T., J.C. and M.-C.W. ; data curation, M.-C.W. ; writing--original draft preparation, S.-Y.H. and C.-Y.H. ; writing--review and editing, H.-U.D. ; visualization, J.-H.K. ; supervision, C.-Y.H. ; project administration, S.-Y.H. and C.-Y.H. ; funding acquisition, C.-Y.H. and H.-U.D. All authors have read and agreed to the published version of the manuscript.