Abstract

The mid-20^th century witnessed an exponential rise in industrialization world-wide, resulting in widespread plastic product pollution. Microplastic (MP) have garnered significant attention due to their persistence and negative ecological consequences. Here, we review the current state of microplastic pollution research in aquatic ecosystems, highlighting the need for a comprehensive understanding of their impacts. A literature review was conducted using a science database up to the year 2023, identifying 200 manuscripts related to the topic. Data were categorized based on the year of publication, continent, taxonomic domain, type of sample, and the classification of MP to understand research trends and biases in geographical and taxonomic scopes. The analysis revealed a consistent increase in microplastic research publications until 2020, followed by a decline in the two subsequent years. The decline in research publications post-2020 underscores the broader impact of external factors, such as the COVID-19 pandemic, on scientific output. The Europe continent emerged as the leading research region. Most studies predominantly focus on eukaryotic organisms, particularly the Kingdom Animalia, with taxonomic emphasis on Arthropoda and fish. The taxonomic focus on eukaryotic organisms, especially within Kingdom Animalia, may limit a comprehensive understanding of the ecological impact of MP. Hence, these studies primarily concentrated on physical characterization, with marine environments receiving the highest attention. Methodological biases toward water samples, marine environments, and physical characterization suggest a need for more balanced research approaches. This comprehensive review analysis highlights the dynamic trajectory of MP research, emphasizing the importance of global collaboration, balanced taxonomic representation, and the need for increased emphasis on freshwater ecosystems.

Keywords: Microplastics; Aquatic pollution; Freshwaters; Review; Waterborne pollutants