1. Cyanotoxins & Human Health
Alison Reeve
Jiaxin Yu
Marshall Ambros
Rachel Beauregard
Steve Hoffmann

2. Problem Statement
Cyanobacteria are capable of producing toxins and have been linked to human health concerns

3. Objectives
Study the behavior of cyanotoxins in the environment and the human body
Thoroughly investigate cyanotoxin's effects on human health in the Lake Champlain Basin. 
Determine precautionary measures to prevent the toxins from further impacting human life and the environment.
Cyanobacteria, commonly known as blue-green algae, have recently been linked to several types of neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), Parkinson's Disease, and Alzheimer’s Disease, which occur through exposure to toxins produced by cyanobacteria.

4. Cyanobacteria History
They’ve been around for 2 billion years
Research on cyanobacteria toxicity began 19th century
Incidence of disease in 20th century caused by:
Population pressure
Global warming
Eutrophication of surface waters
Increased monitoring/awareness
Unknown factors?
Charmichael 2001

5. Cyanotoxin Receptors Humans Livestock Ducks
Zooplankton (some indication)
Fish?
Shellfish?
DeMott 1991, EPA 2005

6. Exposure Eating contaminated food Drinking contaminated water
Swimming or dermal exposure
Inhalation
ALS
Gastroenteritis, liver and kidney damage, death
Skin rashes
Irritation of eyes, nose, throat, skin, and respiratory tract

7. Cyanobacteria Prokaryotic Photosynthesizing
Important primary producer in aquatic ecosystems
Nuisance “blooms” in eutrophic environments
Some species produce toxins

8. Eutrophication Phosphorus loading Algae Blooms Agricultural runoff
Stormwater runoff
Algae Blooms

9. Algae Blooms Other Contributing Factors Effects on Ecosystem
Nitrogen concentrations
Water temperature
Light
Morphology of the impoundment
Effects on Ecosystem
Anoxia
Toxic Blooms

10. Toxic Cyanobacteria 2,000 species: ~ 40 known to produce toxins
Anabaena spp.
Microcystis spp.
Planktothrix spp.
Nostoc spp.
Nodularia spumigena
Microcystis aeruginosa
Planktothrix rubescens
Nodularia spumigena

11. Cyanotoxins Neurotoxins Anatoxin-a Anatoxin-as Saxitoxin
β-Methylamino-L-alanine (BMAA)
Hepatotoxins
Microsystin-LR
Nodularin-R
Cytotoxins
Cylindrospermopsin
Gastrointestinal and dermatotoxins
Aplysiatoxin
Lyngbyatoxin a
Anatoxin-as
Anatoxin-a
BMAA
Microcystin LN
Nodularin R
Cylindrospermopsin
Aplysiatoxin

12. Neurotoxins Anatoxin-a mimics acetylcholine
Anatoxin-as is structurally different from Anatoxin–a and is highly toxic
Saxitoxin is usually associated with red tides in marine ecosystems
Responsible for paralytic shelfish poisoning
Been detected in some freshwater species
Anatoxin-a
Acetylcholine

13. Hepatotoxins Cyclic peptides Cause liver damage
Long term exposure can lead to liver cancer

14. Past Cases First known linked case found in Guam
Caruaru, Brazil, Summer 1996
Dialysis center used water contaminated with microcystins
23 patients died in first 2 weeks, 37 more within 5 weeks

15. Funari E, Testai E. Toxigenic cyanobacteria from marine, brackish and freshwaters. Chart. Critical Reviews in Toxicology, Feb2008; 38(2):98 Available from: Academic Search Premier, Ipswich, MA. Accessed March 20, 2010.

16. Funari E, Testai E. Toxigenic cyanobacteria from marine, brackish and freshwaters. Chart. Critical Reviews in Toxicology, Feb2008; 38(2): 101 Available from: Academic Search Premier, Ipswich, MA. Accessed March 20, 2010.

17. BMAA neurotoxin Caused by over 30 species of cyanobacteria:
Ex. Microcystis, Anabaena, Nostoc, Planktothrix
Can cause motor neuron disease or death
Accumulates in brain tissue
Found in Guam and linked to ALS

18. Amyotrophic Lateral Sclerosis (ALS)
Neurodegenerative disease
About 2 per 100,000 people in US
Can be caused by the neurotoxin BMAA
Symptoms
Muscle weakness (including speech muscles)
Twitching and cramping of muscles
Trouble with speech
Shortness of breath, trouble swallowing
Death by suffocation

19. Parkinson’s Disease (PD)
Neurodegenerative Disease
Symptoms
Rigidity of muscles, slowing of movement
Muscle spasms or tremors
Loss of smell, blinking, smiling
Speech changes (soft, monotone, repetition)
Dementia in later stages

20. Alzheimer’s 7th leading cause of death Most common form of dementia
Destroys brain cells leading to memory loss, confusion, changes in personality, mood, behavior, problems with language

21. Primary Liver Cancer (PLC)
Most common form of liver cancer
About 90% of liver cancer patients have this form
Low 5-year survival rate
1.6 million people are diagnosed every year

22. Water Treatment Techniques
Must use several methods in conjunction to eliminate both cells and toxins
Coagulation/flocculation/sedimentation are good first steps, followed by:
filtration with membrane, sand or activated charcoal
Final treatment with UV light or ozone
Burlington water intake is located in deep water, forty feet below the surface. Cyanotoxins and cells accumulate in shallows and near water surface.

23. Still Unknown
Why certain species of cyanobacteria produce toxins only sometimes
If chronic diseases are actually caused by cyanotoxins
What causes algal blooms
What factors besides shallow, stagnant water and phosphorus loading
How to effectively remove cyanotoxins from water

24. Exposure in Lake Champlain
Algal blooms in St. Albans Bay and Mississquoi Bay – not all toxic
Drinking water- only during major blooms
Ingestion or dermal contact
Swimming- dermal contact
Can lead to acute or chronic diseases, none reported thus far
Dog deaths from swimming
Only problem in summer

25. Algae via Remote Sensing
Can detect different types of blooms using aerial imagery
Each bloom has a different color
Color change from Southern to Northern lake due to blooms in the summer
Apparent on Google Maps

26. Potential Cyanotoxin Producing Species in Lake Champlain
2003 Frequency of Occurrence - Percent of Samples
Taxon
Main Lake
South Lake
Missisquoi Bay
St Albans and other
Northeastern Bays
Anabaena flos-aquae 83 29 57 53
Anabaena spp. 51 50 43 58
Microcystis aeruginosa 47 94 56
Coelosphaerium spp. 34 4 44
Gloeotrichia spp. 1 5 9
Aphanizomenon
flos-aquae 73 22 49
Samples Analyzed
102 14
175 45

27. Lake Champlain’s Algae Problem
Not sure what causes toxicity
Algae blooms are caused by:
P/Nutrient/N cycles thrown off
Lack of/not enough BMP’s in place
Missisquoi Bridge
Turtle Habitat
Urban/Residential runoff
Transportation

28. Wetlands
Many wetlands have reached their holding capacities for nutrients
LCBP wetland preservation
Nutrients released when wetlands are destroyed
Could construct more in key areas, but it would only be a temporary fix

29. Recommendations

30. The Three Aspects Prevention Increase public and government awareness
Continuation of research and monitoring

31. Prevention To prevent cyanobacterial blooms
To prevent human exposure to cyanotoxins

32. Cyanobacterial Bloom Prevention
Prioritization
Riparian Buffers
Constructed Wetlands

33. Human Exposure Prevention
Water treatment methods and technology
Coagulation/Flocculation/filtration + UV light treatment
Provisional guidelines (World Health Organization)

34. Public Awareness Get Connected Be Informed Demand Actions
Clean Water Action
Be Informed
Demand Actions

35. Monitoring Areas with repetitive cyanobacterial blooms
Areas with cyanotoxin exposure reports

36. Research
The behaviors and mechanisms of the cyanobacteria and toxins in both water and the human body.
To develop effective water treatment 36

37. Questions?

38. Resources:
DeMott, W.R. et al. (1991) Effects of Toxic Cyanobacteria and Purified Toxins on the Survival and Feeding of a Copepod and Three Species of Daphnia. Carmichael Limnology and Oceanography, 36, 7, “International Symposium on Cyanobacterial Harmful Algal Blooms” U.S. Environmental Protection Agency < Carmichael, WW. (2001) Health Effects of Toxin-Producing Cyanobacteria: “The CyanoHABs”. Human and Ecological Risk Assessment, 7, 5, Parkinsons.org Alsa.org Alz.org LCBP.org