# An Exploratory Review of Microplastic Pollution, Associated Microbiomes and Pathogens in Water
## 1 Introduction  
Plastics, since their invention in 1907, have become commonly used in many branches of industry, ranging from food packaging to medicine [1]. In 2023, global plastic production reached approximately 413.8 million tons, with around 47% originating from Asia. China remained the largest producer, accounting for 32% of global output. In the same year, the European plastics industry achieved a positive trade balance of approximately EUR 12.7 billion [2, 3]. Both their abundance in the environment and some industrial processes can result in the formation of microplastic particles (MP, <5 mm), which have recently become the subject of intense research due to their negative effects on the aquatic environment. Plastic, including MPs, accounts for up to 95% of marine waste, and notably, these materials are highly resistant to degradation, which leads to their long-term environmental persistence [4; 5; 6]. MPs found in the environment, including in surface water, can come from various sources including food production, cosmetics, health care, and many others. Its particles enter water through, among other things, malfunctioning treatment plants and runoff with heavy rains from land into water, etc. [4; 5]. Their presence is associated with a wide range of adverse effects on aquatic organisms. As demonstrated by the study conducted by [PERSON] and [PERSON] [7] on Norway lobsters (_Nephrops norvegicus_) in Scotland, bioaccumulation can be one of such effects. More recent studies confirm the presence of microplastics in _N.s norvegicus_ from various regions, including Irish waters and the Mediterranean Sea. In particular, the study by [PERSON] et al. [8] found microplastics in the gastrointestinal tract of these crustaceans, indicating their ability to accumulate such particles. Moreover, a literature review by [PERSON] et al. [9] indicates that the microplastic burden in benthic marine invertebrates such as _N. norvegicus_ depends on species traits and feeding ecology, which may influence the extent of bioaccumulation. In a study by [PERSON] et al. [10] on the economically important estuarine apex predator _Cynoscien acoupa_ (n = 552), it was shown that MPs were detected in more than half of the fish examined. Additionally, it was noted that MPs accumulated more frequently in adults than juveniles. With accumulation in the body, heavy metals, chemicals, polymeric or oligomeric substances can be released from MP; however, this depends on the phycochemical structures of MP and environmental conditions [11; 12]. In addition to fish, the bioaccumulation of microplastics has been widely documented in various other aquatic organisms, including bivalves, crustaceans, zooplankton, and marine mammals. Filterfeeding bivalves such as _Mytilus_ edulis and _Crassostrea gigas_ can accumulate microplastics in their digestive glands and soft tissues, which can result in oxidative stress, immune response alteration, and decreased reproductive capacity [13; 14]. Similarly, microplastics have been detected in copepods and cladocerans, affecting feeding behavior and energy acquisition at the base of the aquatic food web [15]. Furthermore, marine mammals such as whales and seals can be exposed through trophic transfer, leading to the presence of plastic particles in gastrointestinal tracts and faeces [16]. These findings underscore the ubiquity of microplastic contamination across aquatic taxa and support the need for holistic ecological assessments. In addition, MP structures can be altered due to interactions with the various systems in the animal organism, including digestive fluids or gastrointestinal microbes, and then accumulate in the gut [11; 17; 18]. Another aspect is the impact of the formation of the microbial community on microplastics. One of the first studies presenting this problem was presented by [PERSON] et al. [19], in which the occurrence of potentially harmful _Ostreops_ sp., _Coolia_ sp., and _Alexandrium taylori_ on MP surfaces was detected. On the other hand, a study by [PERSON] et al.