Nanomaterials' Multigenerational Effects by Single and Joint Exposure in Non-mammalian Models

Nanotoxicology has mainly focused on single-generation studies, leaving multigenerational toxicity underexplored. Having animal welfare recently gained importance, we aimed to provide the state-of-the-art of knowledge about multigenerational effects in non-mammalian models in the case of nanomaterials (NM) single and joint exposure to other substances, pollutants, and environmental conditions. Studies on multigenerational effects have increased in recent years, with nanoplastics being the most studied NM, followed by Ag- and TiO₂-based ones. The nematode Caenorhabditis elegans was the most studied test species, followed by Daphnia spp., a microcrustacean, and Danio rerio fish. Common effects included altered life-history traits, oxidative stress, and NM transfer to offspring. Co-exposure effects varied as synergistic toxicity or alleviating effects were observed. We highlight the need for studies on other widely produced NM, such as carbon-based materials, and advocate multigenerational assessments to better evaluate long-term ecological risks within a realistic approach.