Discipline: Ecology Environmental and Earth Sciences
Room: Exhibit Hall A
Nashali I. Ramos Carrasquillo - Universidad Ana G. Mendez, Recinto de Carolina, P.R.
Co-Author(s): Dr. Frances Lugo Alvarado, Universidad Ana G. Mendez, Recinto de Carolina, P.R.
The contamination of freshwater is a rising concern due to its use for recreational purposes and as a tourist attraction. The main objective of this research is to identify the presence and concentration of heavy metals lead, cadmium, and zinc in Rio Tanamá, located in the municipality of Arecibo, Puerto Rico. Another aspect of this study is determining the bioabsorption capacity of river algae for future heavy metal bioremediation and measurement of chlorophyll α and ß from the collected algae sample and those exposed to heavy metals in order to understand their health during the absorption of heavy metals. Algae samples were collected during the summer and fall of 2018. The heavy metals used for the samples collected in the summer of 2018 were zinc and lead; while cadmium was added to the fall samples. The importance of identifying lead, cadmium, and zinc is due to the harmful effects on the ecosystems and public health. Water and algae samples taken from Rio Tanamá were examined using the Ultraviolet-Visible Light spectrophotometer (U-VLS) and the Atomic Absorption Spectrophotometer (AAS). U-VLS was used to identify the amount of chlorophyll α and ß in the algae samples collected. AAS was used to identify and measure the presence and concentration of heavy metals. Algae samples were exposed to different concentrations of heavy metals for a period of 24 to 48 hours to identify the algae capacity of absorption. Samples were then digested with nitric acid, and run through the AAS to obtain the concentration of heavy metals absorbed by algae. Water samples collected underwent digestion and measurement of heavy metal concentration using AAS. With the results obtained, we were able to identify the presence of heavy metals in the water, their concentration in algae, and the algae absorption capacity. The heavy metal concentration found in the water was compared to the standards established by the Junta de Calidad Ambiental (JCA). Results obtained demonstrated levels above those established by the JCA; while zinc was below the established by JCA. The water results for the fall of 2018 are in process. The results for summer 2018 indicate that the algae absorbed lead and zinc when compared with their control. While the algae collected in fall (2018) absorbed cadmium and lead when compared to controls, yet zinc was not absorbed when compared to those controls. Also, a decrease of chlorophylls during 24-hour exposure was seen in the summer 2018 algae samples. Therefore, we can conclude that algae can absorb heavy metals lead, cadmium, and zinc, but organism damage can occur. In future studies, we will compare the results during the four seasons of the year, extend algae exposition to heavy metals exposition more days, identify the algae species, and add other heavy metals.
Funder Acknowledgement(s): HSI-STEM and Articulation Program 'Competency Development Approaches: Increasing STEM Awareness and Retention to Narrow the Achievement Gap of Hispanic Students'; Funded by the US Department of Education PR/AWARD NUMBER P031C1602222; Puerto Rico Louis Stokes Alliance For Minority Participation (PR-LSAMP)
Faculty Advisor: Dr. Frances Lugo Alvarado, firstname.lastname@example.org
Role: My tasks are carried out with the methods of calibration of heavy metals, extracting the samples from the Tanam? river, digest the samples, extract the chlorophyll from the samples, work with the atomic absorption spectrophotometer and Ultraviolet Visible Light spectrophotometer, reach conclusions.