In a newly published USGS study of cyanobacterial blooms in Midwest lakes, taste-and-odor compounds were found almost every time cyanotoxins were found, indicating odor may serve as a warning that harmful toxins are present.
“It is commonly believed that there are no health risks associated with taste-and-odor compounds,” said Dr. Jennifer Graham, USGS limnologist and lead scientist on this study. “While taste-and-odor compounds are not toxic, these pungent compounds were always found with cyanotoxins in the blooms sampled. This finding highlights the need for increased cyanotoxin surveillance during taste-and-odor events so that the public can be advised and waters can be effectively treated.”
Cyanotoxins are produced by some cyanobacteria. Cyanobacteria commonly form a blue-green, red or brown film-like layer on the surface of lakes and reservoirs. This phenomenon is frequently noticed in the United States during the summer, but also occurs during other seasons.
Cyanotoxins can be poisonous to people, aquatic life, pets and livestock. Removing or treating affected water can be both costly and time-intensive. Cyanotoxins are currently on the U.S. Environmental Protection Agency’s drinking-water contaminant candidate list, and many states include cyanotoxins in their freshwater beach-monitoring programs.
“Exposure to these toxins has caused a range of symptoms including skin rashes, severe stomach upset, seizures, or even death,” said Dr. Keith Loftin, USGS research chemist and environmental engineer. “Pets and livestock are most susceptible to direct exposure, but people can also be affected during recreation, by eating contaminated foods, or by drinking contaminated water that has not been treated properly.”
For this study, a cyanobacterial bloom from each of 23 lakes in Iowa, Kansas, Minnesota and Missouri was sampled and analyzed for thirteen toxins and two taste-and-odor compounds. Lakes were targeted based on a known history of cyanobacterial bloom occurrence.
Microcystins, a specific type of toxin, are often the only cyanotoxin considered when evaluating risks associated with cyanobacteria in waters used for recreation or drinking water supply. Microcystins were found in all samples; however, this study also indicates that toxins other than microcystins may be more common than previously thought.
Taste-and-odor compounds were detected in 91 percent of samples. Since toxins occurred more frequently than taste-and-odor compounds, odor alone does not provide sufficient warning to ensure human-health protection against cyanotoxin exposure.
If you think you see a harmful algal bloom, avoiding it is the first course of action. A good second step is to notify local authorities responsible for the affected area, such as a lake manager, state health department, or other relevant state agencies.
The full journal article, published by Environmental Science and Technology, as well as additional information, photos, and an audio podcast about cyanobacteria, can be accessed at http://toxics.usgs.gov/highlights/algal_toxins/.
Kara Capelli | EurekAlert!
Listening in: Acoustic monitoring devices detect illegal hunting and logging
14.12.2017 | Gesellschaft für Ökologie e.V.
How fires are changing the tundra’s face
12.12.2017 | Gesellschaft für Ökologie e.V.
DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.
Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
15.12.2017 | Power and Electrical Engineering
15.12.2017 | Materials Sciences
15.12.2017 | Life Sciences