RT journal article
T1 Photochemical treatment strategies for okadaic acid degradation: Effects of salinity, oxidants, and UV sources
A1 Moreno Andrés, Javier
A1 Lage, Sandra
A1 Catarina Braga, Ana
A1 Reis Costa, Pedro
A2 Tecnologías del Medio Ambiente
K1 Phycotoxin
K1 Seawater toxicity
K1 Seawater treatment
K1 UV-LED
K1 Advanced oxidation processes
AB This study evaluates the degradation and detoxification of okadaic acid (OA), a marine biotoxin, through UV-assisted photochemical processes using environmentally relevant OA concentrations. Experiments were conducted in distilled water (DW) and artificial seawater (ASW), applying two UV sources: UV-LED (λmax = 275 nm) and low-pressure mercury lamp (LP-Hg; λ = 254 nm), combined with hydrogen peroxide (HP), sodium peroxydisulfate (PDS), and potassium peroxymonosulfate (PMS). Photolysis alone was ineffective, and kinetic rate constants (kobs; min−1) followed the trend UV/PMS > UV/PDS > UV/HP for both UV sources. While all treatments showed high OA removal (>79 %) in DW, degradation was significantly reduced for HP (72.8 %–89.9 %) and PDS (67.8 %–76.6 %) in ASW. In contrast, UV/PMS efficacy improved in saline media, achieving rapid and effective degradation of OA, and reaching 99 % detoxification (PP2A activity) within 15 min. The main transformation product, norokadanone (m/z 757.453), formed via decarboxylation, showed significantly reduced toxicity compared to OA. These results confirm the suitability of sulfate radical-based processes (particularly UV/PMS) for OA mitigation in marine environments. In addition, this work highlights the critical role of water matrix composition in marine toxin treatment and supports the development of scalable, mercury-free strategies for effectively mitigating hazardous compounds in coastal environments.
PB Elsevier
SN 0025-326X
YR 2025
FD 2025
LK http://hdl.handle.net/10498/37344
UL http://hdl.handle.net/10498/37344
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 22-sep-2026