Warming waters cited as key factor in new Spanish health study
By Summit Voice
SUMMIT COUNTY — The impacts of global warming are often described in the context of human activities or how it will affect charismatic megafauna and visible landscape features.
But at a much more fundamental biological level, increasing temperatures also appear to be having a huge effect on basic ecosystem components like bacteria — especially cyanobacteria, blue-green aquatic organisms that helped oxygenate the earth’s atmosphere during the early stages of life’s development on the planet, 3.5 million years ago.
According to a study by Spanish researchers, populations of cyanobacteria are increasing, with no signs of a slow down. The study suggests global warming is the cause, and warns that the accelerated growth may also lead to an increase in the amount of toxins produced by some of these populations.
In Spain, the relation between the proliferation of toxic cyanobacteria in the Doñana wetlands and the death rate of wild fauna in this natural space has been confirmed, but of even more concern are its effects on human health.
“Cyanobacteria love warm water, therefore an increase in temperature during this century may stimulate their growth, especially … of the cytotoxic varieties, which could even produce more toxins and become more harmful”, said Rehab El-Shehawy, a researcher from IMDEA Agua and co-author of the study published in the journal, Water Research. Her team is working on developing efficient tools to monitor the number of cyanobacteria in water.
Blooms of these microorganisms in lakes, reservoirs and rivers all over the world, and in estuaries and seas, such as the Baltic, are becoming a more and more frequent phenomenon. According to the experts, this poses an economic problem affecting water sanitation, shipping and tourism. It also presents an environmental problem, as the toxins can affect internal organs, the nervous system and other bodily functions.
“These toxins may affect the liver and other organs (hepatotoxins), the nervous system (neurotoxins), different cells (cytotoxins), the eyes and mucous membranes, as well as causing dermatitis and allergies”, said Francisca F. del Campo, another co-author and researcher at the Autonomous University of Madrid.
The scientists warned that the issue needs much more attention from public heath authorities and the general public.
“We suspect that these cytotoxins may be behind some gastrointestinal disorders and other illnesses, but epidemiological studies are required to confirm this”, said Del Campo.
According to studies carried out by the Centre for Studies and Experimentation of Public Works (CEDEX), approximately 20 percent of Spanish reservoirs (278 were sampled) revealed cyanobacteria in concentrations in excess of standards for bathing water quality set by the World Health Organization.