Microplastic pollution in water, sediments and commercial fish species from Ciénaga Grande de Santa Marta lagoon complex, Colombian Caribbean.

Microplastics are emerging pollutants that have been found in different environmental matrices of marine and coastal ecosystems, where they can generate harmful ecological impacts. Little is known about the current state of microplastic pollution in fragile tropical lagoon ecosystems, such as Ciénaga Grande de Santa Marta (CGSM) in the Caribbean coast of Colombia. This study assesses microplastic pollution in surface waters and sediments, and the occurrence of microplastic ingestion in commercially important fish species from CGSM. In waters, microplastic abundances ranged from 0.0 to 0.3 items L-1 while in sediments they varied from 0.0 to 3.1 items kg-1. The most abundant types of microplastics are fibers and fragments, with polypropylene, polyethylene and high-density polyethylene as the most abundant polymers. Also, 100 (i.e. 21.1%) out of 474 individuals from nine fish species had microplastics in their digestive tracts. Microplastics present in water and sediments and in the digestive tract of the analyzed fish species have similar characteristics, also showing a moderate and statistically significant association. Microplastic abundances are higher near river mouths and in urban areas with a high density of fishing activities and aquaculture infrastructures, which are important sources of contaminants. Microplastic pollution in CGSM represents a threat to the lagoon ecosystem and to local people depending on artisanal fishing. Consequently, effective actions to reduce pollution and its socio-environmental impacts are urgently required.

Comparative Genomics of Clinical and Environmental Isolates of Vibrio spp. of Colombia: Implications of Traits Associated with Virulence and Resistance.

There is widespread concern about the increase in cases of human and animal infections caused by pathogenic Vibrio species due to the emergence of epidemic lineages. In Colombia, active surveillance by the National Institute of Health (INS) has confirmed the presence of Vibrio; however, in routine surveillance, these isolates are not genomically characterized. This study focused on the pangenome analysis of six Vibrio species: V. parahaemolyticus, V. vulnificus, V. alginolyticus, V. fluvialis, V. diabolicus and V. furnissii to determine the genetic architectures of potentially virulent and antimicrobial resistance traits. Isolates from environmental and clinical samples were genome sequenced, assembled and annotated. The most important species in public health were further characterized by multilocus sequence typing and phylogenomics. For V. parahaemolyticus, we found the virulent ST3 and ST120 genotypes. For V. vulnificus, we identified isolates belonging to lineages 1 and 2. Virulence gene homologues between species were found even in non-pathogenic species such as V. diabolicus. Annotations related to the mobilome, integrative mobile and conjugative elements and resistance genes were obtained from environmental and clinical isolates. This study contributes genomic information to the intensified surveillance program implemented by the INS to establish potential sources of vibriosis in Colombia.