Evaluation of Sargassum Recycling Options through Risk-Based Approaches
Full Proposal Submitted to the HCSHWM on
April 10, 2024
PRINCIPAL INVESTIGATOR: Helena Solo-Gabriele, PhD
AFFILIATION: University of Miami, Dept. of Chemical, Environmental, and Materials Engineering
CONTACT INFORMATION: hmsolo@miami.edu, 305-989-9103
PhD. STUDENT: Brittany Mc Intyre, MS
AFFILIATION: University of Miami, Dept. of Environmental Science and Policy
CONTACT INFORMATION: bzm4@miami.edu, 479-502-7413
UNDERGRADUATE STUDENT: Melanie Cerna, AA
AFFILIATION: University of Florida, Dept. of Environmental Engineering Sciences
CONTACT INFORMATION: mcern009@fiu.edu, 786-574-1025
ABSTRACT
Sargassum’s high arsenic concentrations have raised concerns about health impacts when repurposed for potential beneficial uses. Potential health impacts depend upon the speciation or specific chemical form of the arsenic, with inorganic forms more toxic than organic forms. The goal of this study is to assess the risk of arsenic from Sargassum in different recycling scenarios. Specifically, the objectives of this study are to 1) evaluatearsenic levels (total and speciation) in products made from recycled Sargassum (compost, biochar, biogas), and to use this information 2) to determine risks to humans from environmental exposures. Baseline risks will be assessed when Sargassum is not managed by leaving it on the beach. These baseline risks will be compared to health risks associated with its reuse as either compost, biochar or biogas. Through this study we will produce dried Sargassum to simulate beach conditions and compost. We will collaborate with commercial vendors to provide biochar (BiocharNow Inc.) and biogas digestate (Rum & Sargassum Inc.). Samples will be analyzed for total arsenic and arsenic species (arsenite, arsenate, monomethylarsonic acid, dimethylarsinic acid, arsenobetaine, and others). Results from the arsenic analysis will be combined with exposure assessments to compute risk. The results of this study can be used to identify beneficial re-use options that are acceptable from a human health perspective.