Titanium in commercial shrimp from anthropized tropical bays and estimated quantities of TiO2

Titanium (Ti) is a metal with low toxicity in organisms; however, Ti in the form of TiO2 nanoparticles is a contaminant of emerging concern. This study determined the concentration of total Ti in the muscle of pink shrimp (Penaeus brasiliensis and P. paulensis) from two anthropized tropical bays (Guanabara and Sepetiba Bays, southeast Brazil) and presented the first estimates of TiO2 in shrimp. Differences in the total Ti concentration were associated with fishing site and season, showing a spatial-temporal trend. The level of anthropization per se did not explain the metal concentration. Both trophic position (δ15N) and trophic habitat (δ13C) of shrimp had negligible influence on the metal concentration. We suggest that Ti point sources into Sepetiba Bay and/or differences regarding fishing sites inside the bays are possible explanations for the results. The estimates of TiO2 in shrimps based on the total Ti concentration are baseline values for future monitoring. Since shrimps are targets of commercial fisheries, monitoring the Ti concentration is a public health interest.