Single and combined effects of increased temperature and methylmercury on different stages of the marine rotifer Brachionus plicatilis

• Published in: Journal of hazardous materials 2024-03, Vol.466, p.133448, Article 133448
• Main Authors: Jeong, Haksoo, Byeon, Eunjin, Lee, Jin-Sol, Kim, Hyung Sik, Sayed, Alaa El-Din H., Bo, Jun, Wang, Minghua, Wang, Da-Zhi, Park, Heum Gi, Lee, Jae-Seong
• Format: Article
• Language: English
• Subjects: Brachionus plicatilis; Global warming; MAPK signaling pathway; Methylmercury; Oxidative stress
• ISSN: 0304-3894; 1873-3336; 1873-3336
• DOI: 10.1016/j.jhazmat.2024.133448

Rapid, anthropogenic activity–induced global warming is a severe problem that not only raises water temperatures but also shifts aquatic environments by increasing the bioavailability of heavy metals (HMs), with potentially complicated effects on aquatic organisms, including small aquatic invertebrates. For this paper, we investigated the combined effects of temperature (23 and 28 °C) and methylmercury (MeHg) by measuring physiological changes, bioaccumulation, oxidative stress, antioxidants, and the mitogen-activated protein kinase signaling pathway in the marine rotifer Brachionus plicatilis. High temperature and MeHg adversely affected the survival rate, lifespan, and population of rotifers, and bioaccumulation, oxidative stress, and biochemical reactions depended on the developmental stage, with neonates showing higher susceptibility than adults. These findings demonstrate that increased temperature enhances potentially toxic effects from MeHg, and susceptibility differs with the developmental stage. This study provides a comprehensive understanding of the combined effects of elevated temperature and MeHg on rotifers. Methylmercury (MeHg) is a widespread and harmful heavy metal that can induce lethal effects on aquatic organisms in even trace amounts. The toxicity of metals can vary depending on various environmental conditions. In particular, rising temperatures are considered a major factor affecting bioavailability and toxicity by changing the sensitivity of organisms. However, there are few studies on the combinational effects of high temperatures and MeHg on aquatic animals, especially invertebrates. Our research would contribute to understanding the actual responses of aquatic organisms to complex aquatic environments. [Display omitted] •Combined effects of increased temperature and MeHg were measured in B. plicatilis.•High temperature and MeHg adversely caused the physiological change of the rotifers.•Bioaccumulation and biochemical responses depend on the stages of the rotifers.•Susceptibility to high temperature and MeHg differed with the developmental stage.