We analyzed δ13C, δ15N and δ18O in the muscle and liver from killer whales stranded on the coast of Japan. The δ15N values in the muscle samples from calves were apparently higher than those in their lactating mothers, suggesting that nursing may result in the higher δ15N values in the muscle samples of calves. The δ15N value in the muscle samples of male and female whales, except for the calves, were positively correlated with the δ13C values and body length, suggesting that the increases in δ15N were due to the growth of the whales and increase in their trophic level. In contrast, the δ18O values in the muscle samples of female whales except for the calves were negatively correlated with the δ13C and δ15N values. The δ18O may be lower in whales occupying higher trophic positions (δ15N), although it might also be affected by geographic and climatic conditions.

Marine benthic polychaete Capitella sp. I is widely known to adapt to polluted habitats; however, its response to xenobiotics under hypoxic conditions has been rarely studied. This research aimed to test the hypothesis that interactive effects of hypoxia and congener BDE-47 of polybrominated diphenyl ethers (PBDE), which is ubiquitous in marine sediments, may alter the settlement of Capitella sp. I. Our results revealed that under hypoxic condition, settlement success and growth in body length of Capitella larvae were significantly reduced compared to those under normoxia of similar BDE-47 concentration. While no significant changes in morphology of settled larvae were noted in both exposure conditions, the presence of BDE-47 could enhance polychaete growth. The present findings demonstrated that the interactive effects of hypoxia and environmentally realistic concentrations of BDE-47 in sediments could affect polychaete settlement, which, in turn, reduce its recruitment and subsequent population size in the marine benthic ecosystem.

Using rare minnow (Gobiocypris rarus) at early-life stages as experimental models, the developmental toxicity of five widely used triazole fungicides (myclobutanil, fluconazole, flusilazole, triflumizole, and epoxiconazole) were investigated following exposure to 1–15 mg/L for 72 h. Meanwhile, morphological parameters (body length, body weight, and heart rate), enzyme activities (superoxide dismutase (SOD), glutathione S-transferase (GST), adenosine triphosphatase (ATPase), and acetyl cholinesterase (AChE)), and mRNA levels (hsp70, mstn, mt, apaf1, vezf1, and cyp1a) were also recorded following exposure to 0.2, 1.0, and 5.0 mg/L for 72 h. Results indicated that increased malformation and mortality, decreased body length, body weight, and heart rate provide a concentration-dependent pattern; values of 72 h LC₅₀(median lethal concentration) and EC₅₀(median effective concentration) ranged from 3 to 12 mg/L. Most importantly, the results of the present study suggest that even at the lowest concentration, 0.2 mg/L, five triazole fungicides also caused notable changes in enzyme activities and mRNA levels. Overall, the present study points out that those five triazole fungicides are highly toxic to the early development of G. rarus embryos. The information presented in this study will be helpful in better understanding the toxicity induced by triazole fungicides in fish embryos.

The re-emergence of schistosomiasis has given rise to ubiquitous concentrations of the primary control agent pentachlorophenol (PCP) in the environment, especially in the surface waters of China. In this study, the effects of environmentally relevant concentrations of PCP, namely, 0.0002, 0.002, 0.02, 0.2, and 2 μmol/L on survival, age at first reproduction, fecundity, length of mothers, and number of molts of Daphnia magna were studied over three generations. The survival of D. magna exposed to 2 μmol/L was significantly affected in the three generations. Toxic effects were enhanced in later generations. Age at first reproduction of F₁and F₂D. magna was significantly slower than that of the controls. The total number of offspring per female exposed to concentrations of 0.002 μmol/L or greater was less (23.5 to 67.6, 9.4 to 73.7, and 3.6 to 83.7 %) than that of the controls in the F₀, F₁, and F₂generations, respectively. The body length of mothers significantly decreased (4.7 to 6.8, 9.6 to 15.1, and 13.3 to 23.2 %) after exposure to 0.002 μmol/L or greater than those of unexposed individuals in the F₀, F₁, and F₂generations, respectively. Dose–response relationships between concentrations of PCP and length and number of molts of D. magna were observed in the F₀to F₂generations. PCP concentrations on the surface waters of China caused adverse effects to D. magna, which increased over successive generations. Significant effects were observed in the third generation. The multigenerational studies were more sensitive than the single-generation experiments. Thus, multigenerational exposure may be more predictive of chronic exposure under field conditions.