Interpreting reports of Blue Green Algae at Lake Texoma 2012

A primer for the recreational user of the lake

Scott Miller – Student - Ph.D., Public HealthWalden University - PUBH-8165-1Instructor: David Anderson, Ph.D.Spring Term, 2012

Photo – Scott Miller

Educational Objectives

• Inform recreational users of Lake

Texoma regarding the recent reports

of cyanobacteria, also referred to as

Blue Green Algae (BGA)

• Address the conflicting guidance from

The U.S. Army Corps of Engineers and

The Grayson County Health

Department

• Recreational users will have more

information to make decisions

regarding the recreational use of Lake

Texoma Photo – Scott Miller

Persons/Groups affected by BGA Reports at Lake Texoma

Background and Current Status

• August, 2011o Various media outlets inform the public on U.S. Army Corps of

Engineers (USACE) reports that BGA levels render Lake

Texoma “unsafe” (Liu, 2011)

o USACE issued a Warning (forbidding contact with the lake) for

portions of Lake Texoma, and placed the entire lake on

Advisory, discouraging lake contact ("BGA update," 2011)

Liu, X. (2011, August 26). Blue-Green Algae Found At Lake Texoma, Water Contact Prohibited. News9.com. Blue-green algae update. (2011). Retrieved from http://www.swt.usace.army.mil/~news/NewsDetail.CFM?ID=589

Background and Current Status, continued 2• Winter 2011 – Spring 2012

o USCAE updates BGA Warning to lake-wide “Advisory” ("Update

12-1-11," 2011)

o April 6, 2012 - USCAE maintains BGA Advisory at Lake Texoma

("March 28," 2012)

• Advisory signs are posted at boat ramps and other places of

public access to Lake Texoma

Lake Texoma BGA update 12-1-11. (2011). Retrieved from http://www.swt.usace.army.mil/~news/NewsDetail.CFM?ID=615

Lake-wide advisory still in place at Lake Texoma; samples taken March 28. (2012). Retrieved from http://www.swt.usace.army.mil/TDR/eNewsStory.cfm?Number=1617

Background and Current Status, continued 3• February 2012

o “Lake Texoma is Open for Business” (Dixon, 2012) • Educational campaign introduced by Grayson County

“Officials” with support from the Lake Texoma Association

• Statements from the “Open for Business” campaign appear to

undermine the USCAE’s educational campaign regarding BGA

• “Chris Duroy is a Marshall County Commissioner. He says last

year's Corps of Engineers warnings scared people from

spending time on the lake.” (Dixon, 2012, para. 6) Dibusiness”. KXII.com. Retrieved from http://www.kxii.com/community/headlines/Grayson_County_Officials_Said_Lake_is_open_for_Business__138525689xon, K. (2012, February 1). Grayson Co. officials say Lake Texoma is “open for.html

Background and Current Status, continued 4• Local business suffer as a result of the BGA warning and a severe

drought

o One marina, reported that at a time when boats should be

launching at a rate of 6 per fifteen minutes, only six boats

entered the water the entire day (Dixon, 2012, para. 3)

• Grayson County Health Department releases a “Blue-Green Algae

Risk Communication Tool” with updated BGA test results from

Lake Texoma (Grayson County Health Department, 2012) Dixon, K. (2012, February 1). Grayson Co. officials say Lake Texoma is “open for business”. KXII.com. Retrieved from http://www.kxii.com/community/headlines/Grayson_County_Officials_Said_Lake_is_open_for_Business__138525689.htmlGrayson County Health Department. (2012). Blue-Green Algae Sampling Data. Grayson County, TX: Grayson County Health Department.

Background and Current Status, continued 5• The USCAE maintains a lake-wide Advisory discouraging contact

with the water of Lake Texoma but maintains that fish may be

consumed if handled properly

• The Lake Texoma Association and Grayson County Health

Department highlight that no reports of adverse human health

effects caused by BGA have been reported subsequent to contact

with the water of Lake Texoma (Grayson County Health

Department, 2012)

• The public, is receiving conflicting messages from Government

agencies, creating confusion in the mind of the recreational user of

Lake TexomaGrayson County Health Department. (2012). Blue-Green Algae Sampling Data. Grayson County, TX: Grayson County Health Department.

What is cyanobacteria and can it harm humans?• Cyanobacteria, also known as blue-green algae, is present in most

lakes in Texas but does not typically present as a threat to humans

o Common descriptions for BGA overgrowth include:• “Pond Scum”• “Stagnant Water”

• Harmful Algae Blooms (HAB’s) occur when conditions permit the blue-

green algae to overgrow other species of aquatic life ("HAB’s," n.d.)

o Causes• Abundant nutrients for BGA, excess nitrogen and phosphorous• Change in lake conditions, i.e., excess sunlight, stagnant water,

high heat

Harmful Algal Blooms (HABs). (n.d.). Retrieved from http://www.tpwd.state.tx.us/landwater/water/environconcerns/hab/

BGA is a threat to human health

• BGA can produce cyanotoxins (Carmichael et al., 2001)

o Neurotoxic anatoxin-a, anatoxin-a(s), saxitoxins, others

• Human poisonings are rare as most people avoid water that has

“pond scum” or a foul odor, which is typical of a HAB

• Water treatment / filtration remediates the threat to human

health

• BGA and its toxins may be ingested by mouth or via inhilation

• Humans have died as a result of exposure to BGA cyanotoxins

o Symptoms include a mild rash through liver toxicity resulting in

deathCarmichael, W. W., Azevedo, S. M., An, J., Molica, R. J., Jochimsen, E. M., Lau, S.,...Eaglesham, G. K. (2001, July). Human Fatalities from Cyanobacteria: Chemical and Biological Evidence for Cyanotoxins. Environmental Health Perspectives, 109 (No. 7), 663-668. Retrieved from http://ehp03.niehs.nih.gov/article/fetchArticle.action?articleURI=info%3Adoi%2F10.1289%2Fehp.01109663

BGA is a threat to human health, 2

• BGA may be associated with neurodegenerative conditions (Holtcamp,

2012)

o Only 5-10% of ALS (Lou Gehrig’s disease) and Parkinson Disease are

due to an inherited genetic mutation, suggesting a role for

environmental causes of these diseases (Holtcamp, 2012, p. A113)

o Cyanotoxins have been found in the brains of people with ALS and

Parkinson Disease, these toxins cause human neurons to undergo

apoptosis (cell death) (Holtcamp, 2012, p. A114)

• Cyanotoxins in the brain do not necessarily mean causality for

neurodenerative conditons, more study is needed (Holtcamp, 2012, p.

A115) Holtcamp, W. (2012, March 1). The Emerging Science of BMAA: Do Cyanobacteria Contribute to Neurodegenerative Disease? Environmental Health Perspectives, 120 (No. 3), A110-A116. doi:10.1289/ehp.120-a110

WHO guidelines regarding BGA (World Health Organization [WHO], 2003, p. 150)

• Low Probability for adverse health effects (based on cell counts in water)o Skin irritation, GI illness. Post Warning Signs onsite to Inform Public.

• Moderate Probability for adverse health effects (based on cell counts in

water)o Potential for adverse short and long term health outcomeso Watch for “scum” on watero Discourage water contact, Post onsite signs, Inform relevant authorities

• High Probability for adverse health effects (based on cell counts in water)o Documented human or animal disease from siteo Potential for acute poisoning & Immediate action to stop water contact

World Health Organization. (2003). Guidelines for safe recreational water environments - Volume 1 - Coastal and Fresh Waters [Issue Brief]. Retrieved from WHO website: http://www.who.int/water_sanitation_health/bathing/srwe1/en/

Conflicting Messages, Uncertain Risks

o HAB occurred in Lake Texoma in 2011 and BGA toxins remain in

Lake Texoma currently• USCAE currently discourages contact with the water based on

the published standards of the World Health Organization• Grayson County Health Department, utilizing different criteria,

suggests there is very little risk associated with water contact– Grayson County has a vested reason to encourage people to

utilize the lake and has received pressure from the business community to react to the USCAE Warnings and Advisory

– Grayson County has undertaken more extensive and precise testing on the water of Lake Texoma

– Grayson County sponsored testing, reveals low levels of cyanotoxins (Grayson County Health Department, 2012)

Grayson County Health Department. (2012). Blue-Green Algae Sampling Data. Grayson County, TX: Grayson County Health Department.

Summary

• BGA and associated toxins, have been found in Lake Texoma

• BGA toxins (cyanotoxins) are capable of causing mild human

diseases such as a rash, GI disturbance or may cause death

• USCAE and Grayson County Health Department have each issued

conflicting guidance for the recreational user of Lake Texoma

o WHO Standards v. “newer” standards produced by an outside

lab but sponsored by The Grayson County Health Department

• Advisory Signs warning of BGA are still present at Lake

Texoma and the USACE currently advise against water

contact

Summary, 2

• Grayson County Health Department and other County Officials,

provide information that the public may use the lake with

reasonable caution

o Grayson County has economic motives to encourage Lake

Texoma visits

o No documented cases of adverse human health have been

reported as a result of exposure to the water of Lake Texoma

• Reporting bias?

Summary, 3

• Interpreting the data from two Government agencies should not

require such a detailed examination of the sources and

methodologies used to make public guidance

• The data seem to indicate that contact with Lake Texoma is safe,

provided that the public avoid areas that are grossly

contaminated with BGA

o Only a detailed examination of the USCAE report would

indicate where the highest concentrations of BGA have been

found at Lake Texoma

o Avoid stagnant water and water with a “scum” on the surface

More information regarding Blue-Green Algae and risks to human health

• The OPTIONAL link below will direct to a short video

presentation on BGA produced by the State of Ohio to

inform residents on dangers and precautions relating to

BGA exposure

http://powerhost.powerstream.net/008/00153/HarmfulAlgalBl

ooms.wmv

• WHO Guidance on BGA

Chapter 8 - Algae and cyanobacteria in fresh water pdf

Questions? Contact: scott.miller2@waldenu.edu

Photo – Scott Miller

ReferencesBlue-green algae update. (2011). Retrieved from http://www.swt.usace.army.mil/~news/NewsDetail.CFM?ID=589

Carmichael, W. W., Azevedo, S. M., An, J., Molica, R. J., Jochimsen, E. M., Lau, S.,...Eaglesham, G. K. (2001, July).

Human Fatalities from Cyanobacteria: Chemical and Biological Evidence for Cyanotoxins. Environmental Health

Perspectives, 109 (No. 7), 663-668. Retrieved from

http://ehp03.niehs.nih.gov/article/fetchArticle.action?articleURI=info%3Adoi%2F10.1289%2Fehp.01109663

Dixon, K. (2012, February 1). Grayson Co. officials say Lake Texoma is “open for business”. KXII.com. Retrieved

from

http://www.kxii.com/community/headlines/Grayson_County_Officials_Said_Lake_is_open_for_Business__138525689.

html

Grayson County Health Department. (2012). Blue-Green Algae Sampling Data. Grayson County, TX: Grayson

County Health Department.

Harmful Algal Blooms (HABs). (n.d.). Retrieved from

http://www.tpwd.state.tx.us/landwater/water/environconcerns/hab/

References

Holtcamp, W. (2012, March 1). The Emerging Science of BMAA: Do Cyanobacteria

Contribute to Neurodegenerative Disease? Environmental Health Perspectives, 120 (No.

3), A110-A116. doi:10.1289/ehp.120-a110

Lake Texoma BGA update 12-1-11. (2011). Retrieved from

http://www.swt.usace.army.mil/~news/NewsDetail.CFM?ID=615

Lake-wide advisory still in place at Lake Texoma; samples taken March 28. (2012).

Retrieved from http://www.swt.usace.army.mil/TDR/eNewsStory.cfm?Number=1617

References

Liu, X. (2011, August 26). Blue-Green Algae Found At Lake Texoma, Water Contact

Prohibited. News9.com. Retrieved from http://www.news9.com/story/15340346/blue-

green-algae-found-in-lake-texoma-water-contact-prohibited

World Health Organization. (2003). Guidelines for safe recreational water environments

- Volume 1 - Coastal and Fresh Waters [Issue Brief]. Retrieved from WHO website:

http://www.who.int/water_sanitation_health/bathing/srwe1/en/

World Health Organization. (2003). Guidelines for safe recreational water environments

- Volume 1 - Coastal and Fresh Waters [Issue Brief]. Retrieved from WHO website:

http://www.who.int/water_sanitation_health/bathing/srwe1/en/