Identification of hazardous nanoparticles present in the Caribbean Sea for the allocation of future preservation projects

Highlights

• The diverse sources of nanoparticles increasingly induce their exposure in the waters of the Caribbean Sea.

• The nanoparticles caused the formation of potentially hazardous elements.

• The identification of nanoparticles is of paramount importance due to being more reactive.

• As, Cd, Pb, Mg, Ni, and V were detected used advanced characterizations.

• The results expound useful information in assessing the environmental risks and for public health.

Abstract

The deposition of remaining nanoparticles in the Caribbean Sea generates the formation of potentially dangerous elements, which influence at the imbalance of ecosystems. The detection of nanoparticles is not simple and the use of conventional methods is difficult application, which is why we highlight the immediacy and importance of this research for the areas of marine biology, urbanism, engineering and geosciences, applied in the Caribbean Sea. The general objective of this study is to evaluate the use of advanced methods for the determination of toxic nanoparticles, which can directly affect the development of marine organisms in the aquatic ecosystem in waters of the Caribbean Sea, favoring the construction of future international public policies with the elaboration of projects capable of mitigating these levels of contamination. The morphology and structure of nanoparticles were analyzed by emission scanning electron microscope with a high-resolution electron microscope. The nanoparticles smaller than 97 nm were identified in different proportions. The morphological analyses indicated nanoparticles' presence in the form of nanotubes, nanospheres, and nanofibers, which were shown in an agglomerated form. The presence of potentially hazardous elements, such as As, Cd, Pb, Mg, Ni and V were verified. In addition, the presence of asbestos in the form of minerals was confirmed, and that of titanium dioxide was found in large quantities. The results provide new data and emphasize the possible consequences to the in the Caribbean Sea, with the identification of dangerous elements (As, Cb, Pb, Hg, Ni and V), harmful to the marine ecosystem. Therefore, there is a need for strict control to reduce contamination of the Caribbean Sea and avoid risks to the ecosystem and public health, through suggestions of international public policies, through constant monitoring and the application of environmental recovery projects in this marine estuary.

Introduction

The presence of potentially dangerous nanoparticles (NPs) in the sea affects the fertilization and development of marine embryos and other existing organisms. These harmful concentrations of dangerous elements negatively enhance biological changes in fauna and flora, directly affecting humans and the ecosystem (Freitas et al., 2018; Gallo et al., 2018; Xia et al., 2018; Silva et al., 2020a; Oliveira et al., 2021). It is estimated that NPs can cause direct toxicity, changes in nutrient bioavailability and secondary risks caused by contact with organic mixtures, provoking alterations in environmental structure (Peralta-Videa et al., 2011; Caspah et al., 2016; Nguyen et al., 2020; Alnadhari et al., 2021). Therefore, the identification and characterization NPs origin are extremely important to avoid these environmental changes, through public policies, with environmental recovery projects.

The NPs can be of organic, inorganic origin or a mixture, from natural sources (for example pollen, sea salt, sand, erosion), secondary causes (oil refinery practices, vehicular traffic, and mining) or from syntheses (carbon nanotubes and metal hydr/oxides) (Civeira et al., 2016; Graca et al., 2018; Oliveira et al., 2019; Silva et al., 2020b). Whether natural or from anthropogenic sources, they appear as spherical, cylindrical or irregularly shaped compounds from connected, accumulated or agglomerated arrangements (Silva et al., 2011a, Silva et al., 2011b). The identification and characterization of these NPs influence their reactivity and the determination of toxicity due to their nanoscale (NIOSH, 2013). Therefore, the geochemical impact as a consequence of the accumulation of NPs is different from the behavior of macromolecules because NPs are, normally, more reactive in the environment (Wigginton et al., 2007; Barreto et al., 2021).

The deposit of NPs in the sea may be due to their presence in atmospheric air or from adsorption/desorption routes of existing organic materials, or even by autogenesis processes (Barreto et al., 2021). The accumulation and permanence of these NPs can induce the formation of potentially hazardous elements (PHEs) (Oliveira et al., 2021). Among these elements are Pb, Cd, TiO₂, As, that are highly toxic, carcinogenic compounds, which can cause autophagy and even changes in the nervous system of the human being (Freitas et al., 2018; Hu et al., 2018; Rojas et al., 2019; Silva et al., 2020a).

However, the methods of identifying EPS in seawater are restricted, and some have precariousness in the technique due to the lack of equipment capable of carrying out complex and advanced analyzes for the identification of these levels of contamination (Wigginton et al., 2007; Restrepo et al., 2012; Gallo et al., 2018; Gonçalves and Bebianno, 2021). Thereby, the identification of PHEs in sea samples through X-ray spectroscopy with energy dispersion (EDS) can be enhanced when coupled with advanced microscopy (Arai et al., 2019; Oliveira et al., 2021). This technique has advantages in providing simple sampling and does not compromise the integrity of the sample, justifying the possibility of identifying the dangerous NPs present in the waters of the Caribbean Sea of 8 different islands located in the city of Cartagena in Colombia through advanced microscopy, the which makes it possible to assess these contamination risks present in this marine estuary.

The general objective of this study is to evaluate the use of advanced methods for the determination of toxic NPs, which can directly affect the development of marine organisms in the aquatic ecosystem in waters of the Caribbean Sea, favoring the construction of future international public policies with the elaboration of projects capable of mitigating these levels of contamination.