Bárbara S. Diogo , Sara Rodrigues , Oksana Golovko , Sara C. Antunes
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引用次数: 0
Abstract
Aquatic ecosystems are increasingly subjected to environmental stressors, including pH fluctuations, and antibiotic contamination, which can disrupt essential biological functions such as metabolism, respiration, and reproduction. The interaction between these stressors presents significant ecological risks, as pH affects the toxicity, pharmacodynamics/kinetics of antibiotics by altering their ionization state and membrane permeability. This study assessed the toxicity of environmentally relevant concentrations of sulfamethoxazole (150 µg SMX/L), trimethoprim (30 µg TRIM/L), and their mixture (MIX: 150 µg SMX/L + 30 µg TRIM/L) under different pH conditions (6.5, 7.5, and 9.0) on Danio rerio juveniles. A multi-biomarker approach was used to assess D. rerio biological health status, including oxidative stress responses, lipid peroxidation, cholinergic neurotransmission, energetic metabolism, and DNA damage. Results revealed that SMX was marginally toxic across all pH scenarios, but caused more severe effects such as oxidative stress, lipid peroxidation, and DNA damage, under acidic pH. In contrast, TRIM toxicity increased at neutral and alkaline pH, causing severe alterations in antioxidant defenses and cellular integrity. The MIX treatment exhibited marginal toxicity at acidic and alkaline pH but was moderately toxic at neutral pH, leading to oxidative stress, lipid peroxidation, and DNA damage. These physiological and metabolic disruptions highlight how antibiotic mixtures, under varying pH conditions, can impair critical biological functions in aquatic organisms. These findings emphasize the urgent need for integrated research addressing multiple environmental stressors, particularly chemical contamination and climate change-driven abiotic factors. Ignoring these threats could lead to irreversible damage to aquatic ecosystems and biodiversity.
期刊介绍:
Environmental Toxicology and Pharmacology publishes the results of studies concerning toxic and pharmacological effects of (human and veterinary) drugs and of environmental contaminants in animals and man.
Areas of special interest are: molecular mechanisms of toxicity, biotransformation and toxicokinetics (including toxicokinetic modelling), molecular, biochemical and physiological mechanisms explaining differences in sensitivity between species and individuals, the characterisation of pathophysiological models and mechanisms involved in the development of effects and the identification of biological markers that can be used to study exposure and effects in man and animals.
In addition to full length papers, short communications, full-length reviews and mini-reviews, Environmental Toxicology and Pharmacology will publish in depth assessments of special problem areas. The latter publications may exceed the length of a full length paper three to fourfold. A basic requirement is that the assessments are made under the auspices of international groups of leading experts in the fields concerned. The information examined may either consist of data that were already published, or of new data that were obtained within the framework of collaborative research programmes. Provision is also made for the acceptance of minireviews on (classes of) compounds, toxicities or mechanisms, debating recent advances in rapidly developing fields that fall within the scope of the journal.