ASSESSMENT OF MICROFIBER CONTAMINATION IN A MANGROVE SENTINEL SPECIES

Abstract

Microfibers have a diameter of less than 50 μm and variable lengths ranging from 1 μm to 5 mm. In addition to their versatility in applications such as textiles, filters, and medical products, these materials also act as potential carriers of additives, including antibacterial agents and dyes, which can leach into the environment and affect local fauna. The effects of these contaminants on organisms, such as the mangrove crab (Ucides cordatus), are assessed through biomarkers—particularly micronuclei—which allow for the detection of non-lethal genotoxic damage. The proposed study investigates whether polyester microfibers exert greater genotoxic effects on Ucides cordatus than cotton microfibers. Two experiments were conducted, one using polyester microfibers and the other cotton microfibers. Crabs were randomly allocated into fifteen 10-L aquaria filled with brackish water (salinity 25). Each aquarium contained six individuals and was assigned to one of the following treatments: (1) Control (fiber-free water), (2) nominal concentration of 0.0001 g/L, and (3) nominal concentration of 0.1 g/L of microfibers. To evaluate genotoxic effects (micronucleated cells), hemolymph samples were collected from the major cheliped of each organism. PERMANOVA results indicated a significant effect of exposure time and increased genotoxicity at 0.1 g/L, demonstrating a dose-dependent response. Although still emerging, studies on microfiber-induced genotoxicity are essential for socio-environmental risk assessment and for informing public policies and sustainable practices in the textile sector