Lake Atitlan is in Crisis
The current bloom of Cyanobacteria Lyngbya Hironymusii on Lake Atitlan has receeded significantly from the November levels, perhaps until next fall. There are still potentialy serious negative health impacts from contact with this form of Blue-Green algae.
There have been many cases of severe dermatitis reported around the lake from people who came in direct contact with the cyanobacteria during attempts to "clean" the lake.
A preliminary report by
Green Water Laboratories in Florida on samples collected November 8 indicates that the levels of: lyngbyatoxin (LT), debromoaplysiatoxin (DAT), aplysiatoxin (AT), cylindrospermopsin (CYN), and saxitoxins (STX) can be classified as “trace amounts”, i.e., the bloom does not produce enough toxins to represent a serious health risk; fish and crab meat should be tested. As the bloom start dying off, the water samples should be retested. The report can be seen on our Facts/Links page.
This DOES NOT MEAN that the lake is free of toxins or that health recommendations to not use water with the cyanobacteria in it domestically should be ignored. There are more tests being done and studies have
shown that cyanobacteria can vary greatly in its levels of toxicity over time.
THE GOOD NEWS is that with cooler weather the bloom is diminishing and tourists can see a beautiful Lake Atitlan once again! Kayaking on parts of the lake where no Blue Green algae can be seen should be relatively safe.
Presentation By Dr. Rejmankova on Nov. 9 in San Pedro La Laguna
Dr. Rejmankova gave a presentation about Lake Atitlan and the Cyanobacterial bloom on Monday afternoon.
- The only way to reverse the bloom is to stop the entrance of phosphor and nitrogen rich nutrients to the lake.
- The presence of high levels of dissolved oxygen in the upper layers of the Lake indicate the bloom is currently in a growth phase.
- Lake Atitlan already has a sufficient load of nutrients to feed the Cyanobacteria for years.
- Planting of Tule reeds and other wetland plants will help mitigate the problem.
- Cyanobacteria Lyngbya Hironymusii is not well understood or well researched.
- The Lyngbya can vary greatly in toxicity, from none at all to toxic, from week to week.
- Lake water should not be used domestically and protective gear should be worn when in direct contact with the lake water.
- Well water should not be greatly affected by the Cyanobacteria.
- There are only a handful of laboratories worldwide with adequate facilities to fully test the toxicity of Lake Atitlans bloom. Results from testing can take weeks.
- Leaving the Cyanobacteria in the lake will help break down toxins faster than removing it from the water.
- Even if the flow of nutrients is greatly reduced we should expect the Cyanobacterial bloom to return and grow larger every year for the next several years, until the existing nutrient load is reduced.
Dr. Eliska Rejmankova, PhD Botany, is currently an Associated Professor in the Department of Environmental Science and Policy (ESP) at the University of California, Davis. She has over 20 years of experience in aquatic and wetland plant ecology.
Official Government Action Plan
The Guatemalan government has released an official action plan. The Spanish language PDF is here. We have a translation on the Facts/Links page.
Salvemos Atitlan
This is an organization comprised of scientists, ecologists, business people, community and government leaders. They have realeased a very current set of recommendations based on a series of meetings over the last weeks. Click Here to see all of their recommendations in english.
http://www.salvemosatitlan.com/