FAST DOWNLOAD
These species represent a serious danger to human health in the Gulf of Fonseca due to the possibility of poisoning by contaminated mollusks.
On August 29, 2024, the Marine Toxins Laboratory of the University of El Salvador (LABTOX-UES) detected the presence of toxic microalgae during monitoring in the Gulf of Fonseca.
The results, presented on September 6 , reveal a high concentration of species such as the dinoflagellate Gymnodinium catenatum , responsible for producing paralyzing venom in mollusks.
The presence of toxic microalgae in the Gulf of Fonseca, shared by El Salvador, Honduras and Nicaragua , has put the area’s populations on alert.
“These microalgae identified in the Gulf of Fonseca belong to species that generate a poison known as paralytic shellfish poison (PMV), which is a neurotoxin capable of seriously affecting human health and even causing death,” explained the director of LABTOX, Óscar Amaya .
The danger generated by these toxic species is more due to the consumption of mollusks (oysters, mussels, clams ), explained the expert.
Amaya noted that the risk to public health posed by toxic algal blooms is prompting research laboratories across Latin America and the Caribbean to collaborate in a joint effort to constantly monitor the oceans.
Monitoring
Coastal monitoring is carried out within the framework of the project “Strengthening regional capacities in Latin America and the Caribbean in the use of nuclear and isotopic techniques.
This is to increase knowledge of the stressors that affect coastal areas and contribute to the sustainable management of marine resources.”
Amaya explained that algal blooms can arise for various reasons, such as temperature, conductivity and nutrient levels, including nitrogen and phosphorus.
“This period of the year is favourable due to the high solar radiation and the rains, which provide nutrients to the sea, and favour the proliferation of these species,” Amaya commented.
Regarding the duration of the presence of these microalgae, Amaya highlighted that it depends on the supply of nutrients to the blooms:
“They can last for days, months or even indefinitely. The greatest risk to the population lies in the consumption of mollusks such as oysters, mussels and clams, which could be contaminated,” he warned.
Results
The monitoring report details that seawater samples were collected at four points in the Gulf of Fonseca.
The samples were analyzed in the laboratory to measure chlorophyll “a”, total nitrogen, total phosphorus, and various physicochemical parameters.
The results revealed that the highest concentration was of the toxic dinoflagellate Gymnodinium catenatum , with 115,520 cells per liter (cel/L) at point 3.
This species is known for its ability to produce paralytic poison (PSP). In addition, the cyanobacterium Komvophoron sp. was identified , with 76,560 cells/L, and the diatom Skeletonema sp. , with 60,280 cells/L at point 1.
Although no visible signs of harmful algal blooms, such as colored patches indicating Red Tide , were observed , the concentration of toxic microalgae was high at the time of sampling.
For this reason, LABTOX recommends intensifying monitoring in the coastal zone, especially in the Gulf of Fonseca, and carrying out PSP toxicity tests on bivalve molluscs in the region.