Chronic exposure to environmentally relevant diazepam alters behaviour, gut microbiome, and offspring phenotype in zebrafish (Danio rerio).

Chronic exposure to environmentally relevant diazepam causes intergenerational neurobehavioral and developmental abnormalities in zebrafish, with effects observed at 1 and 10 μg/L concentrations.

• Why it matters: Understanding the ecological risks of psychoactive drugs like diazepam is crucial because they are widespread in aquatic environments due to incomplete wastewater removal, yet their long-term and mechanistic impacts on aquatic organisms are poorly understood.
• What they did: Adult female zebrafish were exposed to diazepam at 1 and 10 μg/L for 28 days, and their offspring were analyzed for gut damage, microbiota disruption, metabolite changes, and neurobehavioral and developmental effects.
• The result: DZP exposure caused gut damage, microbiota and metabolite profile disruptions, impaired oocyte development, reduced GABA levels, and led to reproductive and neurobehavioral deficits in offspring, indicating profound intergenerational toxicity.