Plastics carry a bacterial biofilm on their surface, called Plastisphere, that is composed of various micro-organisms. The presence of potential human pathogenic bacteria (PHPB) and antibiotic resistant bacteria (ARB) in the plastisphere has been described.
In this study, we used a combination of metabarcoding and standard antibiotic susceptibility testing to study the pathobiome and resistome of macroplastics, fish guts and the environment in a marine aquaculture farm. Plastics were found to be higher in PHPB from the Vibrionaceae family (Fig. 1) compared with environmental samples. Moreover, isolates from aquaculture plastics showed higher significant multiple antibiotic resistance (MAR) compared to non-plastic samples of seawater, sediment and fish guts (Fig. 2). These results suggest that plastics act as a reservoir and fomite of PHPB and ARB in aquaculture, potentially threatening the health of farmed fish and human consumers.
Through its great characteristics, plastic has spread through human society. It is a light, solid, and inexpensive material, making it ideal for long-term purposes as well as for single uses. All industrial sectors rely on plastics, and aquaculture make no exception since plastics are ubiquitous in aquaculture structures. This ubiquity raises the concern of the threat they could represent for reared species and human consumers. Plastics has deleterious effects through direct mechanicals actions, but also through indirect chemical intoxication or biological contamination, subsequent to ingestion of microplastics or cutaneous contact with plastic equipment.