Microplásticos em ambientes aquáticos: uma abordagem sobre padrões metodológicos no Brasil, contaminação em peixes e percepção ambiental nas Baías de São Marcos e São José, Maranhão.

Abstract

Plastic pollution is one of the major global environmental threats, with microplastics (MPs) standing out as particularly concerning contaminants due to their widespread distribution and potential impacts. In this context, this study adopted an interdisciplinary approach to investigate the scientific knowledge, occurrence, and environmental perception related to microplastics. Initially, a systematic literature review was conducted to identify and analyze scientific publications on the presence of microplastics in Brazilian environments, as well as the methodological approaches employed. Subsequently, fish species collected from three sampling sites in the Maranhão Gulf were analyzed to assess the occurrence of microplastics in gastrointestinal tissues and muscle. The samples were processed and examined under laboratory conditions. Finally, structured questionnaires were applied in the communities of Coqueiro (São Marcos bay) and Pau Deitado (São José bay) to evaluate environmental perception among local residents. The results showed that research on microplastics has been carried out across all regions of Brazil, with a predominance of studies in marine environments and a lack of integrated data across environmental compartments. The findings also highlight the need for methodological standardization and the inclusion of analyses in edible tissues. Microplastics were detected in both the stomach and muscle of fish at all sampling sites, making this one of the first studies to record the occurrence of microplastics in muscle samples of fish found in Brazil. The estimated daily intake suggested that fish consumption may represent a pathway for human exposure to microplastics, although at relatively low levels. Regarding environmental perception, the surveyed communities demonstrated limited knowledge about microplastics, despite showing greater awareness of contamination in the studied bays. Overall, these findings reinforce the need for future studies to adopt standardized, interdisciplinary, and collaborative approaches in order to support more integrated assessments of environmental risks and potential impacts on human health.