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Big Buzz News
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- story by Ellis Anderson
The Mississippi beach closures have made national news, but there’s lots of misinformation out there. So The Shoofly Magazine reached out to the U.S. Geological Survey (which is one of the national agencies researching harmful algal blooms – or HABs), the Center for Disease Control, the Mississippi Department of Health, and the MS Department of Environmental Quality (MDEQ) with some questions. |
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Is the culprit a bacteria or an algae? We’ve heard it called both.
The proper terminology now, according the Liz Sharlot, Director of Communications at the Mississippi Department of Health is “Algal,” pronounced, “All-gul.”
The University of California’s Museum of Paleontology says that:
Cyanobacteria are aquatic and photosynthetic, that is, they live in the water, and can manufacture their own food. Because they are bacteria, they are quite small and usually unicellular, though they often grow in colonies large enough to see. They have the distinction of being the oldest known fossils, more than 3.5 billion years old, in fact!
It may surprise you then to know that the cyanobacteria are still around; they are one of the largest and most important groups of bacteria on earth…
Do other places in the country have problems with HABs?
For example, Lake Erie, which is bordered by the states of Michigan, Ohio, Pennsylvania and New York (and the Canadian province of Ontario), has been battling significant problems for years.
We don’t remember having blue/green algal blooms before here on the Mississippi Gulf Coast. Why now?
Water from the Mississippi River, laden with nitrogen and phosphorus, causes the "Dead Zone" in the Gulf of Mexico each year. It's one of the largest dead zones in the world, since the Mississippi River drains America's agricultural heartland along the river's vast valley and watershed: Minnesota, Iowa, Illinois, Wisconsin, Missouri, Tennessee, Arkansas, Mississippi, and Louisiana.
This article from Montana State University, explains that "nitrogen and phosphorous enter the river through upstream runoff of fertilizers, soil erosion, animal wastes, and sewage. In a natural system, these nutrients aren't significant factors in algae growth because they are depleted in the soil by plants.
"However, with anthropogenically increased nitrogen and phosphorus input, algae growth is no longer limited. Consequently, algal blooms develop, the food chain is altered, and dissolved oxygen in the area is depleted.
The size of the dead zone fluctuates seasonally, as it is exacerbated by farming practices. It is also affected by weather events such as flooding and hurricanes."
To ease the threat of flooding along the lower Mississippi River this year, the Bonne Carre spillway was opened, allowing that nutrient-rich “fresh” water to pour into Lake Ponchartrain and directly out into the Mississippi Sound.
The river water changed the natural salinity of the lake and the Sound, providing a fertile environment for the cyanobacteria to grow. This story by the National Centers for Coastal Ocean Science (a branch of NOAA), published July 10th gives more info.
The short video below contains some excellent - and astonishing - animations. (there's no sound, but it's captioned).
How long will the algal bloom last?
While tropical surges might push in water with higher saline content, the rainfall from a tropical event could add to the fresh water problem in the Sound.
A spokesman for MDEQ said that "it is too soon for us to speculate given the uncertain characteristics and impacts of the storm at this time; however, our beach program will be monitoring along the coast as soon as possible after the storm passes.
"It is our understanding that algae that washes ashore would likely dehydrate and die. We encourage everyone to be aware of their surroundings, and if they see a Harmful Algal Bloom after the storm passes to contact MDEQ and/or local emergency management officials."
UPDATE - July 17: MDEQ conducted water tests after Barry passed through and says the results warrant leaving the water contact warnings in place. Click here for the full July 17 press release.
Is it safe to go onto the beach?
The water contact warning was extended on July 2 to include segment of the Jourdan River in Hancock County from the I-10 bridge to the mouth of the river into St. Louis Bay. MDEQ recommends that people avoid activities such as swimming, wading, and fishing. People should also avoid eating fish or anything else taken from this section of the river until further notice.
The CDC offers this advice: "People should stay out of waters that have an odd color (brown, red, turquoise, etc.), smell bad, or that have floating algal mats on them. People should also take extra care to keep dogs out of the blooms to prevent them from becoming sick."
So direct contact with cyanobacteria in the water can cause problems. Are there other ways that it can affect people?
Cyanobacterial toxins can be incorporated into airborne water droplets that people and animals can inhale.
People or animals can be directly exposed to cyanotoxins in freshwater during recreational activities or by breathing in aerosolized toxins (toxins in water turned into tiny airborne droplets or mist). People or animals exposed to cyanotoxins through direct skin contact or inhalation may experience the following symptoms:
- Skin irritation
- Eye irritation
- Nose irritation
- Throat irritation
- Respiratory irritation
There is still much to learn about the health effects of airborne exposure to chemicals and toxins released by cyanobacterial blooms.
CDC and partners previously conducted studies assessing the health effects from recreational exposure to cyanobacterial toxins in small lakes with ongoing blooms. After one hour of exposure to blooms, we found small amounts of microcystins on nasal swabs from study participants and microcystins in the water and in aerosols generated by the recreational activities. However, study participants did not report any symptoms after one hour of exposure.
What are the lingering effects on the environment, if any?
The CDC points out that: "Cyanobacterial blooms might also be a problem as they die off. The rotting organic matter can give off hydrogen sulfide, which may cause respiratory irritation, especially in people with asthma."
Have there been any reports of illness from the bloom in the Mississippi Sound?
Is there any connection between cyanobacteria and Vibrio?
No. No. And No.*
Liz Sharlot says the two bacteria are “completely unrelated.”
However, while we’re on the subject: Vibrio, sometimes known by the alarmist moniker, “flesh-eating-bacteria,” is present across the Gulf Coast. Infections are required to be reported to the CDC and the Mississippi Department of Health.
Mississippi has been keeping track of its own cases since 1998 and Sharlot says that "typically, we expect to see it every year, like the West Nile virus.”
In Mississippi, there's been a low of two reported Vibrio cases in 1999 and a high of 23 cases reported in 2005, (the year of Hurricane Katrina). Vibrio can come from eating infected raw oysters and from exposure in water. Statistics on the cause of the Mississippi cases weren’t immediately available, but nationally, the majority of Vibrio infections come from eating seafood, in most cases, raw oysters or clams. In Mississippi, so far this year, three cases have been reported.
“[Infection from Vibrio] is preventable," says Sharlot. “The main idea is to protect yourself. If your immunity is low or you’re taking some types of medication, you shouldn’t go into warm, brackish water if you have a cut and your skin is exposed.”
The CDC says the following people have a higher risk:
Anyone can get sick from vibriosis, but you may be more likely to get an infection or severe complications if you:
- Have liver disease, alcoholism, cancer, diabetes, HIV, or the blood disorder thalassemia.
- Receive immune-suppressing therapy for the treatment of disease, such as cancer.
- Have an iron overload disease, such as hemochromatosis.
- Take medicine to lower stomach acid levels, such as Nexium and Pepcid.
- Have had recent stomach surgery.
Sharlot advised people who aren’t high-risk to take precautions as well if they have a cut.
*Fox News 13 in Memphis actually published a piece pointing to Vibrio as the cause of Mississippi beach closures. We encourage you to contact them, requesting that they remove the piece.