The sargassum that arrives in the DR has high concentrations of arsenic
SANTO DOMINGO. The sargassum varieties that reach the shores of country do concentrations de arsenic which exceed that bounds established to international to be used in agricultural work and animal feeding. This is revealed by a study conducted by researchers from the Instituto Tecnológico de Santo Domingo (INTEC) who analyzed the concentration of heavy metals in the algae.
The research, published in the scientific journal Marine Pollution Bulletin, consisted of harvest of samples of the three varieties of seaweed that reach the coasts of the country in eight beaches, with the objective of analyzing the presence of heavy metals in its composition to determine the possibility of its use in agriculture.
The INTEC researchers detected the presence of eleven heavy metals, having the iron, arsenic y zinc in the highest concentrations. Also cadmium in the samples from three of the beaches, nickel in five and lead in six.
Rolando Liranzo, Aris Mendis Gomez, Bolivar Gomez, Yusmel Gonzalez-Hernandez y Ulises Jauregui-Haza collected samples of the three varieties of sargassum that arrive in the country: S. fluitans III, S.nathans I y Nathans VIII, on eight beaches in the national territory in the year 2021. They were the beaches of Bávaro and Punta Cana, in La Altagracia; Juan Dolio and Guayacanes, in San Pedro de Macorís; San Andres, in Santo Domingo; Nigua, in San Cristóbal; Enriquillo, in Barahona and Juancho in Pedernales.
The research is part of the research work produced by students of the PhD in Environmental Sciences offered at INTEC.
The findings were compared with the two previous studies on the presence of metals in the algae that reach the coast of the island and it was found that the reported arsenic values are two times higher than those reported in samples collected in 2015 and 2019. cobalt, chlorine, cadmium, nickel and zinc values were lower; while for copper and lead they were in the same range as in previous studies.
"When comparing our results with the range of maximum values established for the use of arsenic in agriculture, soils and animal feed, we observe that, in all cases, the arsenic content in the samples studied is within that range or exceeds it, which constitutes a limitation for purposes of use in agriculture”, specifies the scientific publication. It indicates that its use for these purposes could cause long-term damage to soils, and potentially pass up the food chain through food.
The investigation confirms the importance of continuing to conduct research on the chemical and organic composition of the sargassum that reaches the country's coasts, before stimulating its use in agricultural work and animal feeding.
The two previous studies on the presence of heavy metals in sargassum were also carried out by INTEC researchers. Fernandez, boluda, Olive, Bill, Gomez, Echavarria, Mendis Gomez presented the study "Prospective elemental analysis of the accumulated algal biomass off the coast of the Dominican Republic in 2015"; while Roof-Roof, Rodriguez-Rodriguez, Luis Rodriguez of Francisco, Omar Paino y boluda they presented “Lead, chromium, nickel, copper and zinc levels in sargassum species reached the coast of the Dominican Republic during 2019”.
Arsenic is a chemical element of the metalloid group and can be found naturally in air, water and soil. Arsenic exposure has been linked to various types of cancer.