In Situ Assessment of Microplastic Ingestion and Physiological Status of Wild Penaeus Shrimp from the Gulf of California

There is a lack of information regarding the presence of microplastics (MPs) and the physiological status of shrimp species such as the brown shrimp (Penaeus californiensis), the blue shrimp (Penaeus stylirostris), and the white shrimp (Penaeus vannamei), all of which are of great economic and ecological value in the coastal waters of the Gulf of California. Shrimp caught in the open sea off the coast of Sinaloa during the fall season were analyzed to determine the microplastic content in the digestive tract, as well as their morphophysiological and biochemical conditions. Microplastic content was classified by size, color, and shape and confirmed using FTIR-ATR spectroscopy. A total of 63 organisms (21 per species) were processed. Significant differences were observed in total plasma proteins and triglycerides, as well as in triglycerides and total lipids in the hepatopancreas, among the species. However, the total MP content, its distribution among organs, and the various MPs classifications did not show significant differences between species or in relation to the organisms’ weight. Three types of polymers were confirmed: polyurethane (45%), polyvinyl ketone (36%), and polyacrylamide (18%). The most abundant MPs were black in color and fiber-shaped, and they ranged in size from 0.12 to 1.37 mm, with the highest concentration found in the organisms’ intestines. A 100% prevalence of MPs was observed in all species. Although no direct effects on the physiological and biochemical status of the species in their natural environment were detected, the variability in the types of MPs could suggest other types of impacts that may not yet be reflected in the indicators we observed.