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Home , Aphanizomenon, Cyanotoxin, Cylindrospermopsin, Microcystin

United States Office of Water EPA-810F11001 Environmental Protection Agency Mail Code 4304T June 2019 and : Information for Drinking Water Systems

Summary in drinking water for children pre-school age and younger (less than six years This fact sheet provides public water systems old). For school-age children through adults, the (PWSs) basic information on human health effects, recommended HA levels for drinking water are at analysis tools, and the effectiveness of various or below 1.6 μg/L for and 3.0 μg/L treatment processes to remove or inactivate four for cylindrospermopsin. Young children are more commonly occurring cyanotoxins in water bodies susceptible than older children and adults as they that are a source of drinking water throughout most consume more water relative to their body of the U.S. Cyanotoxins are listed on the EPA’s weight. fourth drinking water Candidate Contaminant List and include, but are not limited to, anatoxin-a, There are currently a few states that have cylindrospermopsin, microcystins, and . established monitoring guidelines and This fact sheet does not address and odor cyanotoxin threshold levels for public water issues caused by the cyanobacteria and will only systems (PWSs). PWSs are responsible for focus on discussions of anatoxin-a, following those guidelines/thresholds and for cylindrospermopsin, microcystins, and saxitoxin. undertaking any follow-up action required by their state. Background The (SDWA) protects public health by regulating the nation's public Causes of cyanobacterial harmful algal drinking water supply, which relies on sources that blooms include: rivers, lakes, reservoirs, springs, and Cyanobacteria are photosynthetic that ground water wells. The SDWA requires the EPA share some properties with and are found to publish a list of unregulated contaminants that naturally in lakes, streams, ponds, and other are known or expected to occur in public water surface waters. Similar to other types of algae, systems in the U.S. that may pose a risk in drinking when conditions are favorable, cyanobacteria can water. This list is known as the Contaminant rapidly multiply in surface water and cause Candidate List (CCL). "blooms." Several types of cyanobacteria, for

example Dolichospermum (previously ) The cyanotoxins included in the most recent CCL flos-aquae, have gas-filled cavities that allow are produced by several species of cyanobacteria them to float to the surface or to different levels (cyanobacteria are known as blue-green algae). below the surface, depending on light conditions No federal regulatory guidelines for and nutrient levels. This can cause the cyanobacteria or their in drinking water or cyanobacteria to concentrate on the water surface, recreational waters exist at this time. The EPA causing a pea-soup green color or blue-green published drinking water health advisories (HA) "scum." Some cyanobacteria, such as for microcystins and cylindrospermopsin in June agardhii, can be found in bottom 2015. The EPA recommends HA levels at or sediments and float to the surface when mobilized below 0.3 μg/L for microcystins and 0.7 μg/L for 1 by storm events or other sediment disturbances. varieties of most of the common -producing Other cyanobacteria blooms may remain cyanobacteria exist, and it is impossible to tell if a dispersed through the water column (such as species is toxic or not toxic by looking at it. Also, Raphidiopsis, previously Cylindrospermopsis sp.) even when toxin- producing cyanobacteria are leading to a generalized discoloration of the present, they may not actually produce toxins. water. Furthermore, some species of cyanobacteria can produce multiple types and variants of Conditions that enhance growth of cyanobacterial cyanotoxins. Molecular tests are available to harmful algal blooms determine if the cyanobacteria, for Factors that promote cyanobacterial bloom formation example, carry the toxin-producing gene. and persistence include: However, quantitative cyanotoxin analysis is • Extended periods of direct sunlight, needed to determine if the cyanobacteria are producing the toxin. Water contaminated with • Elevated nutrient availability (especially cyanobacteria can occur without associated taste phosphorus and ), and odor problems. • Elevated water ,

• pH changes, In most cases, the cyanobacterial toxins naturally • An increase in precipitation events, exist intracellularly (in the cytoplasm) and are • Calm or stagnant water flow, and water column retained within the . Approximately 95% of stability/lack of vertical mixing. anatoxin-a and the variants are found intracellularly during the growth stage of the Although bloom conditions in much of the U.S. are bloom of certain cyanobacteria species. When the more favorable during the late summer, the cyanobacteria cell dies or the cell membrane interrelationship of these factors causes large ruptures or is stressed, the toxins are released into seasonal and year-to-year fluctuations in the the water (called “extracellular” toxins). cyanobacteria levels. Some toxin-producing strains However, more significant proportions of other can occur early in the summer season while others cyanotoxins such as cylindrospermopsin, can be are only found during late summer. naturally released to the water by the live cyanobacterial cell. The reported ratio is about 50% intracellular and 50% extracellular during Effects of cyanobacterial harmful algal the growth stage of the bloom. Extracellular blooms toxins may adsorb to clays and organic material in the water column and are generally more Cyanobacterial blooms can be harmful to the difficult to remove than the intracellular toxins. environment, animals, and human health. The bloom decay consumes , creating hypoxic conditions which result in plant and animal die- Health effects caused from exposure to off. Under favorable conditions of light and cyanotoxins nutrients, some species of cyanobacteria produce Exposure to cyanobacteria and their toxins could toxic secondary metabolites, known as occur by of drinking water cyanotoxins. Common toxin-producing contaminated with cyanotoxins and through direct cyanobacteria are listed in Table 1. The contact, inhalation and/or ingestion during conditions that cause cyanobacteria to produce recreational activities. The recreational cyanotoxins are not well understood. Some exposure to cyanobacterial blooms and their species with the ability to produce toxins may not cyanotoxins can result in a wide range of produce them under all conditions. These species symptoms in humans including fever, headaches, are often members of the common bloom- muscle and joint pain, blisters, stomach cramps, forming genera. Both non- toxic and toxic , , mouth ulcers, and allergic 2 reactions (see Table 1). Table 1. Cyanotoxins on the Contaminant Candidate List (CCL)

Number Primary 1 Most Common Cyanobacteria Cyanotoxin of Organ Health Effects 2 Variants Affected Producing Toxin Microcystis, Dolichospermum (previously Anabaena), Nodularia,

Microcystins >100 Planktothrix, Fischerella, Nostoc, Abdominal pain Oscillatoria, and Gloeotrichia Vomiting and diarrhea Liver inflammation and Raphisiopsis (previously hemorrhage Cylindrospermopsis) raciborskii, Acute pneumonia 3 Liver flos-aquae, Acute dermatitis Aphanizomenon gracile, damage Aphanizomenon ovalisporum, Cylindrospermopsin Potential tumor growth Umezakia natans, Dolichospermum promotion bergii, Dolichospermum lapponica, Dolichospermum planctonica, wollei, Rhaphidiopsis curvata, and Rhaphidiopsis mediterranea Chrysosporum (Aphanizomenon) ovalisporum, Cuspidothrix, 2-6 Nervous Tingling, burning, Raphisiopsis, Cylindrospermum, System numbness, drowsiness, Dolichospermum, Microcystis, incoherent speech, Oscillatoria, Planktothrix, 3 Anatoxin-a group salivation, respiratory Phormidium, Dolichospermum paralysis leading to flos-aquae, A. lemmermannii (symptoms Raphidiopsis mediterranea observed in animals (strain of Raphisiopsis raciborskii), Tychonema and Woronichinia Tingling, numbness, Aphanizomenon flos–aquae, headaches, dizziness, Dolichospermum circinalis, Lyngbya nausea, vomiting and wollei, Planktothrix spp. and a Nervous Saxitoxin >50 diarrhoea, temporary Brazilian isolate of Raphisiopsis System blindness, paralysis and raciborskii. death

1 Sources: Health Effects Support Documents (HESD) for microcystins, cylindrospermopsin and anatoxin-a (US EPA c,d,e) and Testai et al., 2016 2 Not all species of the listed genera produce toxin; in addition, listed genera are not equally as important in producing cyanotoxins. 3 The anatoxin-a group does not include the organophosphate toxin anatoxin-a(S) as it is a separate group. In the US, the most common member is thought to be anatoxin-a, and thus this toxin is listed specifically.

3 Such effects can occur within minutes to days after available for the presence or absence of exposure. In severe cases, seizures, liver failure, cyanotoxins. If cyanotoxins are detected by a field respiratory arrest, and (rarely) death may occur. The screening kit, repeat analysis is recommended cyanotoxins include (which affect the using either a quantitative ELISA test or one of the nervous system), hepatotoxins (which affect the other analytical methods identified in Table 2. liver), and dermatoxins (which affect the skin). More precise, quantitative ELISA test kits are However, there have been new studies of effects in available for microcystins/ (including other systems, including hematological, kidney, ADDA-ELISA), saxitoxin, anatoxin-a, and cardiac, reproductive, and gastrointestinal effects. cylindrospermopsin. Although they provide rapid There is evidence that long-term exposure to low results, ELISA kits generally have limitations in levels of microcystins and cylindrospermopsin may selectivity and are not congener specific and promote cell proliferation and the growth of tumors. recognizing different congeners can vary However, more information is needed to determine quantitatively due to different cross-reactivities. the carcinogenicity of both microcystins and cylindrospermopsin. Methods that utilize liquid combined with (LC/MS) can There have been many documented reports of dog, precisely and accurately identify specific bird and livestock throughout the world as microcystin congeners for which standards are the result of consumption of surface water with available. LC/MS methods have also been cyanobacterial blooms. In 1996, 116 patients at a designed to minimize matrix interference. renal dialysis clinic in Caruaru, Brazil experienced Currently, a few standards for a limited number headache, eye pain, blurred vision, nausea and of the known microcystin congeners are vomiting when they were exposed intravenously to available. If congener-specific information is water containing a mixture of microcystin and needed, an LC/MS (ion-trap, tandem mass cylindrospermopsin (Carmichael et al., 2001). spectrometry, TOF) method should be Subsequently, 100 of the affected patients considered. Although HPLC-PDA methods are developed acute liver failure and, of these, 76 died. less selective than LC/MS methods and the Analyses of , sera, and liver samples from the quantitation is more problematic due to sample patients revealed only the microcystin toxin. matrix interference, they could provide a measure of resolution of the congeners present. You may also consult the EPA Frequently Asked Analytical Methods Questions: Laboratory Analysis for Microcystins Table 2 describes the methods available for in Drinking Water for more information. cyanotoxin measurement in freshwater. For drinking water, the EPA developed Method 544, a liquid Sample handling considerations chromatography/tandem mass spectrometry Samples must be handled properly to ensure (LC/MS/MS) method for microcystins and reliable results. Detailed procedures are typically (combined intracellular and extracellular), Method specified in the particular analytical 545, a LC-ESI/MS/MS method for the determination methods/SOPs. Water systems should obtain and of cylindrospermopsin and anatoxin-a, and Method follow sample collection and handling procedures 546, an ADDA-ELISA method. established by the laboratory performing the Commercially available Enzyme-Linked analysis. Laboratories establishing such Immunosorbent Assay (ELISA) test kits are one of procedures should adhere to analytical method the more commonly utilized cyanotoxin testing defined protocols but may also consult the USGS methods, since they do not require expensive sampling protocol Guidelines for design and equipment or extensive training to run. Semi- sampling for cyanobacterial toxin and taste-and- quantitative field screening ELISA kits are odor studies in lakes and reservoirs (2008). 4 Table 2. Methods Available for Freshwater Cyanotoxin Detection

Methods Anatoxins Cylindrospermopsin Microcystins Saxitoxin

Biological Assays Mouse Yes Yes Yes Phosphatase Inhibition No No Yes Assays (PPIA) Neurochemical Yes No No Enzyme-Linked Immunosorbent Assays (ELISA) Yes Yes Yes Yes Chromatographic Methods Gas Chromatography Gas Chromatography with Flame Ionization Detection (GC/FID) Yes No No No Gas Chromatography with Mass Spectrometry (GC/MS) Yes No No No Liquid Chromatography Liquid Chromatography / - Visible Detection Yes Yes Yes Yes (LC/UV or LC/PDA) Liquid Chromatography/ Fluorescence (LC/FL) Yes No No Yes Liquid Chromatography Combined with Mass Spectrometry Liquid Chromatography Ion Trap Mass Spectrometry (LC/IT MS) Yes Yes Yes Yes Liquid Chromatography Time-of- Flight Mass Spectrometry Yes Yes Yes Yes (LC/TOF MS) Liquid Chromatography Single Quadrupole Mass Spectrometry Yes Yes Yes Yes (LC/MS) Liquid Chromatography Triple Quadrupole Mass Spectrometry Yes Yes Yes Yes (LC/MS/MS)

a residual disinfectant, e.g., , should be Among the most important sample handling quenched immediately upon sampling. Sodium considerations are the following: thiosulfate or ascorbic acid are commonly used • Collection – Bottle type, volume, and as quenching agents and their appropriateness preservative used depend on the laboratory doing can be specific to the analytical method the analysis. Generally, samples should be selected to meet the monitoring data quality collected and stored in amber glass containers to objectives. For example, EPA Method 544, an avoid potential cyanotoxin adsorption associated LC/MS/MS technique for measuring six with plastic containers and to minimize exposure microcystin congeners and nodularin in to sunlight. drinking water, specifies the use of ascorbic • Quenching – samples (particularly acid, along with other sample preservation “finished” drinking water samples) that include reagents. On the other hand, EPA Method 546 5 (an ELISA technique for measuring “total remove or inactivate them in several ways. Some microcystins” and nodularin in drinking water), treatment options are effective for some exclusively specifies the use of sodium cyanotoxins, but not for others. Effective thiosulfate and prohibits the use of ascorbic management strategies depend on understanding acid. The different approaches are deliberate the growth patterns and species of cyanobacteria and designed to meet method performance that dominates the bloom, the properties of the goals that include established criteria for cyanotoxins (i.e., intracellular or extracellular), sample hold times. and appropriate treatment processes. For • Chilling – samples should be cooled example, oxidation of microcystin depends on the immediately after collection, during shipping, chlorine done, pH and the temperature of the and pending analysis at the laboratory. water. Applying the wrong treatment process at a Depending on the analytical method being used, specific state in treatment could damage cells and sample freezing may be appropriate to extend result in the release rather than removal of holding times, taking precautions to avoid cyanotoxins. breakage. Table 3 summarizes the effectiveness of different Sample analysis considerations types of water treatment to remove intact cyanobacteria cells and treatment processes that When measuring both intracellular and extracellular are effective in removing extracellular dissolved toxins, rupturing cyanobacterial cells (lysing) is toxins of several of the most important generally employed to break the cell wall and cyanobacteria. You may also consult the EPA release the toxins into solution. Freeze/thaw Water Treatment Optimization for Cyanotoxins cycling, traditionally carried out over three or more document for more information. cycles, is the most common lysing technique, though some analytical methods rely on other approaches. Lysing is particularly important for To avoid the release of cyanotoxins into the samples collected prior to the PWS filter effluent. water, drinking water treatment operators can For a well-designed, well-operated PWS, lysing undertake different management strategies to deal would not be expected to have a significant impact with cyanobacteria blooms. For example, those on finished water (post-filtration) samples as drinking water utilities that have access to more cyanobacteria cells should not be present at than one intake can switch to an alternate source significant levels in the finished water. However, that is not as severely impacted by the bloom. laboratories must carefully follow the requirements Another management alternative is to adjust of the analytical methods and mandated monitoring intake depth to avoid drawing contaminated water programs, which may require lysing for all samples. and cells into the treatment plant. Some analysts elect to confirm the effectiveness of raw-water lysing (or to judge the need for finished- Pretreatment oxidation at the intake poses several water lysing) using microscopic examination for concerns with respect to lysing cells and releasing intact algal cells. toxins. Copper and ozone at the intake are not recommended because of the risk of lysing algal cells. Chlorination, in addition to lysing the Cyanotoxin treatment and bloom cells, has the potential to produce disinfection by- management products during water treatment. If pretreatment oxidation is needed, it is important to carefully Once cyanobacteria and/or their cyanotoxins are evaluate the influent, as successful pre-oxidation detected in the surface water supplying the water depends on the algal species, oxidant and dose. system, the treatment system operators can act to

6 Table 3. Cyanotoxin Treatment Processes and Relative Effectiveness

Treatment Process Relative Effectiveness

Intracellular Cyanotoxins Removal (Intact Cells) Oxidation often stresses or lyses cyanobacteria cells releasing the cyanotoxin to the water. If oxidation is required to meet other treatment Pre-treatment objectives, consider using lower doses of an oxidant less likely to lyse cells. oxidation If oxidation at higher doses must be used, sufficiently high doses should be used to not only lyse cells but also destroy total toxins present (see extracellular cyanotoxin removal). Effective for the removal of intracellular toxins (cyanobacteria cells). Coagulation/ Ensure that captured cells accumulated in sludge are removed frequently Sedimentation/ so as not to release toxins. Ensure that sludge supernatant is not returned Filtration to the supply after sludge separation. Effective for removal of intracellular cyanotoxins (cyanobacteria cells). Microfiltration and ultrafiltration are effective when cells are not allowed Membranes to accumulate on membranes for long periods of time. More frequent cleaning may be required during a HAB. Flotation processes, such as Dissolved Air Flotation (DAF), are effective for Flotation removal of intracellular cyanotoxins since many of the toxin-forming cyanobacteria are buoyant. Extracellular (Dissolved) Cyanotoxins Removal Depends on the type of cyanotoxin, membrane material, membrane pore size distribution, and influent water quality. Nanofiltration is generally effective in removing extracellular microcystins. Reverse osmosis filtration Membranes is generally applicable for removal of microcystins and cylindrospermopsin. Cell lysis is highly likely. Further research is needed to characterize performance. Potassium Effective for oxidizing microcystins and anatoxins. Further research is Permanganate needed for cylindrospermopsin. Not effective for oxidizing saxitoxin. Very effective for oxidizing microcystins, anatoxin-a, and Ozone cylindrospermopsin. Not effective for oxidizing saxitoxin. Chloramines Not effective. Chlorine dioxide Not effective at doses typically used in drinking water treatment. Effective for oxidizing microcystins as long as the pH is below 8. Effective Free Chlorine for oxidizing cylindrospermopsin and saxitoxin. Not effective for oxidizing anatoxin-a. UV radiation alone is not effective at oxidizing microcystins and cylindrospermopsin at doses typically used in drinking water treatment. UV Radiation When UV radiation is coupled with ozone or peroxide (called “advanced oxidation”), the process is effective at oxidizing anatoxin-a, cylindrospermopsin, and with high UV doses, microcystins. 7 Treatment Process Relative Effectiveness Powdered activated carbon (PAC): Effectiveness of PAC adsorption varies based on type of carbon, pore size, type of cyanotoxin, and other water quality parameters such as NOM concentration. Wood-based activated carbons are generally the most effective at microcystins adsorption. More research is needed to evaluate PAC’s effectiveness at adsorbing cylindrospermopsin, anatoxin-a, and saxitoxin, however the limited research has demonstrated promising results. Doses in excess of 20mg/L may be needed for complete toxin removal, especially if NOM Activated Carbon concentrations are high. Adsorption Granular activated carbon (GAC): Effectiveness of GAC adsorption varies based on type of carbon, pore size, type of cyanotoxin, and other water quality parameters such as NOM concentration. GAC is effective for microcystins, and likely effective for cylindrospermopsin, anatoxin-a and saxitoxin. The condition of the carbon is an important factor in determining GAC’s effectiveness for cyanotoxin removal. GAC may need to be regenerated more frequently to ensure adequate adsorption capacity for HAB season.

In-line application of powdered activated carbon activated carbon, membrane filtration and (PAC) could also be used to remove any toxins that chemical inactivation (disinfectants and oxidants). may have been released. Both powdered activated carbon (PAC) and granular activated carbon (GAC) have been

effective in adsorbing microcystins and Intracellular cyanotoxin removal cylindrospermopsin, although microcystin The conventional drinking water treatment processes variants may have different adsorption (coagulation, flocculation, sedimentation and efficiencies. The performance of activated carbon filtration) can be effective in removing intracellular depends on the concentration of the toxin, influent cyanotoxins (cyanobacteria cells). Coagulation, water quality (i.e., NOM concentration), PAC flocculation and dissolved air flotation (DAF) are dose, and type of activated carbon. Jar tests are more effective than sedimentation. Microfiltration recommended to test the effectiveness of various and ultrafiltration are highly effective at removing PAC types and doses, with the implementation of intact cyanobacterial cells. During an active bloom, the carbon with the greatest capacity for removal operators may need to alter process parameters to of the target contaminants. GAC filters are account for the increased loading of cyanobacteria. It effective in removing microcystins if they are may be necessary to backwash filters more properly regenerated to ensure adequate frequently to prevent retained cells from releasing adsorption capacity is maintained. Nanofiltration intracellular toxins. and reverse osmosis may be effective in removing cylindrospermopsin and microcystin. However, Physical removal of extracellular cyanotoxins site specific tests are recommended as removal efficiency depends on the membrane pore size Common treatment techniques for the removal of distribution and water quality. extracellular toxins include adsorption by

8 Oxidation of extracellular cyanotoxins adequate CT1 values can be guaranteed to ensure Ultraviolet (UV) radiation is not effective at typical efficient oxidation of lysed cyanobacteria and the water treatment plant doses. Much higher doses are resulting extracellular cyanotoxins. required to photolytically destroy microcystin, anatoxin-a, and cylindrospermopsin. For example, Drinking water operators are encouraged to UV inactivation dose for Cryptosporidium parvum is monitor the treated water to confirm the removal about 40 mJ/cm2, while the photolytic destruction of cyanotoxins. dose for microcystin, cylindrospermopsin, anatoxin- a and saxitoxin ranges between 1530 to 20,000 Developing a Risk Management Plan 2 mJ/cm . UV has been used along with a catalyst Water supply managers should consider (e.g., ozone, hydrogen peroxide, or titanium dioxide) developing a risk management plan for to oxidatively decompose the toxins (this is typically cyanobacterial bloom occurrence, especially called advanced oxidation). However, the those systems with source waters that are effectiveness of this process is largely dependent on susceptible to HABs. Elements of such a plan the organic content of the water. should include monitoring, treatment and communication components. The plan could Oxidants such as free chlorine, ozone and include a monitoring program to determine permanganate can be used to inactivate microcystins sampling locations and schedule; sample volume; but free chlorine’s effectiveness is pH-dependent whether to sample for cyanobacterial cells or (ideal range is 6-8). Anatoxin-a is resistant to specific cyanotoxins or both; which analytical oxidation by free chlorine. Ozone is an effective screening test to use; and conditions when it is oxidant for microcystins, but its efficacy may be necessary to send sample(s) to an identified affected by the presence of organic matter. Ozone laboratory for confirmation. The EPA published can also be used as an oxidant for anatoxin-a and Recommended Recreational Ambient Water cylindrospermopsin; however, ozone is pH- Quality Criteria or Swimming Advisories for two dependent for the oxidation of anatoxin-a (pH 7 to Cyanotoxins, Microcystins and 10) and for cylindrospermopsin (4 and 10). Ozone is Cylindrospermopsin, that public water systems not effective for oxidizing saxitoxin. Permanganate could use as part of the monitoring program is effective in oxidizing microcystin and anatoxin-a during a severe bloom event with high levels of (from pH 6 to 8), but is not effective for cyanobacteria and cyanotoxins in a surface water cylindrospermopsin. Chloramines and chlorine used for recreation and as a supply for drinking dioxide are not effective treatments for microcystin, water treatment facilities. As part of the anatoxin-a or cylindrospermopsin. management plan, water supply managers should also develop strategies for effective treatment Formation of disinfection by-products is another approaches to reduce the potential of cyanotoxins potential problem with the use of ozone, copper in the finished water. Additionally, as part of the sulfate, and chlorine when there are high bromide plan, water supply managers should develop a concentrations in the water. However, results communication plan that identifies the required from studies on the impact of chlorination of cell- communication steps to coordinate with the bound toxins and resulting disinfection by- agencies involved, the appropriate actions that products formation are contradictory. Most of the must be taken, and the steps to inform consumers findings suggest that pre-chlorination should and the public. The following are potential EPA ideally be avoided during blooms, unless resources for developing a management plan:

1 A CT value is used in the calculation of disinfectant dosage for time with the water being disinfected (typically expressed in units chlorination of drinking water. A CT value, the product of the of mg-min/L). concentration of a drinking water disinfectant and the contact 9 • Recommendations for Public Water Systems http://www.umweltdaten.de/publikationen/fpdf- to Manage Cyanotoxins in Drinking Water l/2910.pdf 7. Chow, C., Drikas M., House J., Burch M., and • Cyanotoxin Management Plan Template and Velzeboer R. (1999) The impact of conventional water Example Plans treatment processes on cells of the cyanobacterium • Drinking Water Cyanotoxin Risk . Water Research, Vol. 33, 15, Communication Toolbox 3253-3262. 8. Codd, G.A., Morrison, L.F., Metcalf, J.S. (2005) Cyanobacterial toxins: risk management for health For more information protection. Tox and Applied Phar. 203, 264-272. Additional information on cyanobacteria and 9. de la Cruz, A. et al (2011) Can we effectively degrade cyanotoxins is available on the EPA’s Cyanobacteria Microcystins? Implications on Human Health. Anti- Harmful Algal Blooms (CyanoHABs) in Water Cancer Agents in Medical Chemistry, 11; 19-37. 10. Dixon, M., Falconet, C., Ho, L., Chow, C., O’Neill B., : https://www.epa.gov/cyanohabs website and Newcombe, G. (2011) Removal of cyanobacterial metabolites by nanofiltration from two treated waters. Additional information and resources about Journal of Hazardous Materials 188, 288 –295 cyanotoxins in drinking water is available on the 11. Dixon, M., Richard Y., Ho, L., Chow, C., O’Neill B., EPA’s Cyanotoxins in Drinking Water web and Newcombe, G. (2011) A coagulation– powdered page: activated carbon–ultrafiltration – Multiple barrier https://www.epa.gov/ground-water-and-drinking- approach for removing toxins from two Australian water/cyanotoxins-drinking-water cyanobacterial blooms. Journal of Hazardous Materials, 186; 1553–1559. Contact Dr. Lesley D’Anglada at the EPA Office of 12. Drikas, M. et al., 2001b. Water Treatment Options for Water at (202) 566-1125 or [email protected] Cyanobacteria and Their Toxins. Proceedings Water Quality Technology Conf., November 11-15,

Nashville, TN

13. Falconer, I. R. and Humpage, A. R. (2006) References Cyanobacterial (blue-green algal) toxins in water 1. Antoniou, M., de la Cruz, A. and Dionysiou, D. (2005) supplies: . Environ. Toxicol, 2; Cyanotoxins: New Generation of Water Contaminants. 299–304. Journal of Environmental Engineering, ASCE, 1239- 14. Falconer, I.R. (2005) Cyanobacterial toxins of 1243. drinking water supplies: Cylindrospermopsins and 2. Brooke, S., Newcombe, G., Nicholson, B. and Klass, microcystins. CRC Press, New York, 279 pp. G. (2006) Decrease in of microcystins LA and 15. Graham, J.L., Loftin, Keith, Ziegler, A.C., Meyer, LR in drinking water by ozonation. Toxicol, 48; 1054- M.T., 2008, Guidelines for design and sampling for 1059. cyanobacterial toxin and taste-and-odor studies in 3. Carmichael, W.W., S.M.F.O. Azevedo, J.S. et al. 2001. lakes and reservoirs: U.S. Geological Survey Scientific Human fatalities from cyanobacteria: Chemical and Investigations Report 2008-5038, 39 pp. online at biological evidence for cyanotoxins. Environ. Health http://pubs.usgs.gov/sir/2008/5038/ Perspect. 109(7):663-668. 16. Graham, J.L., Loftin, Keith, Ziegler, A.C., Meyer, 4. Centers for Disease Control and Prevention (CDC). M.T., 2008, Cyanobacteria in Lakes and Reservoirs: Environmental Hazards & Health Effects Program. Toxin and Taste-and-Odor Sampling Guidelines U.S. Harmful Algal Blooms (HABs) website: Geological Survey Techniques of Water-Resources http://www.cdc.gov/hab/ Investigations, book 9, chap. A7, section 7.5 on line at 5. Chorus, I. (2001) Cyanotoxins: occurrence, causes, http://water.usgs.gov/owq/FieldManual/Chapter7/7.5.h consequences. Springer, New York, 357 pp. tml 6. Chorus, I. (2005) Current approaches to cyanotoxin 17. Health Canada (2002) Guidelines for Canadian risk assessment, risk management and regulations in Drinking Water Quality: Supporting Documentation. different countries. Dessau, Germany: Federal Cyanobacterial Toxins - Microcystin-LR. Available Environmental Agency, (Umweltbundesamt). ISBN online at: http://www.hc-sc.gc.ca/ewh- 0175- 4211, 122pp. Available online at: semt/pubs/water-eau/cyanobacterial_toxins/index- 10 eng.php 30. U.S. EPA (2015a). Drinking Water Health Advisory 18. Ho, L., Lambling, P., Bustamante, H., Duker, P., for the Cyanobacterial Toxin Microcystin. EPA Newcombe, G. (2011) Application of powdered 820R15100. Available online at: activated carbon for the adsorption of https://www.epa.gov/sites/production/files/2017- cylindrospermopsin and microcystin toxins from 06/documents/microcystins-report-2015.pdf drinking water supplies. Water Research, Vol. 45 (9), 31. U.S. EPA (2015b). Drinking Water Health Advisory 2954–2964 for the Cyanobacterial Toxin Cylindrospermopsin. 19. Ho, L., Slyman, N., Kaeding, U., Newcombe, G. EPA 820R15101. Available online at: (2008) Optimizing PAC and chlorination practices for https://www.epa.gov/sites/production/files/2017- cylindrospermopsin removal. Journal of American 06/documents/cylindrospermopsin-report-2015.pdf. Water Works Association, 100; 88-96. 32. U.S. EPA (2015c) Health Effects Support Document 20. Jurczak, T. (2005) Elimination of microcystins by for the Cyanobacterial Toxin Microcystins. EPA water treatment processes—examples from Sulejow 820R15102. Available online at: Reservoir, Poland. Water Research, Vol. 39, (11); https://www.epa.gov/sites/production/files/2017- 2394 - 2406. 06/documents/microcystins-support-report-2015.pdf. 21. Merel S., Clément, M., Mourot, A., Fessard V. and 33. U.S. EPA (2015d) Health Effects Support Document Thomas, O. (2010) Characterization of for the Cyanobacterial Toxin Cylindrospermopsin. cylindrospermopsin chlorination. Science of the Total EPA 820R15103. Available online at: Environment, 408; 3433–3442. https://www.epa.gov/sites/production/files/2017- 22. National Health and Medical Research Council 06/documents/cylindrospermopsin-support-report- (NHMRC) (2004). Australian Drinking Water 2015.pdf Guidelines 34. U.S. EPA (2015e) Health Effects Support Document 23. (ADWG). Available online at: for the Cyanobacterial Toxin Anatoxin-a. EPA http://www.nhmrc.gov.au/publications/synopses/eh19s 820R15104. Available online at: yn.htm#comp https://www.epa.gov/sites/production/files/2017- 24. Paerl, H., Hall, N. and Calandrino, E. (2011) 06/documents/anatoxin-a-report-2015.pdf Controlling harmful cyanobacterial blooms in a world 35. U.S. EPA (2015f). Recommendations for Public Water experiencing anthropogenic and climatic-induced Systems to Manage Cyanotoxins in Drinking Water. change. Science of the Total Environment, 409; 1739– EPA-815R15010, Washington, DC; 2015. Available 1745. from: https://www.epa.gov/sites/production/files/2018- 25. Rapalaa, J. et al (2002) Endotoxins associated with 11/documents/cyanotoxin-management-drinking- cyanobacteria and their removal during drinking water water.pdf treatment. Water Research, 36; 2627–2635. 36. U.S. EPA (2019). Recommended Recreational Ambient 26. Rositona, J., Newcombe, G., Nicholson, B. and Water Quality Criteria or Swimming Advisories for Sztajnbok, P. (2001) Ozonation of NOM and Algal two Cyanotoxins, Microcystins and Toxins in Four Treated Waters. Water Research, 35; Cylindrospermopsin EPA-822R19001, Washington, 23-32. DC; 2015. Available from: 27. Snider, B. and Xie, C. (2004) Chapter 2. Total https://www.epa.gov/wqc/recommended-human- synthesis of (±)-cylindrospermopsin. Strategies and health-recreational-ambient-water-quality-criteria-or- Tactics in Organic Synthesis, Academic Press, 4; 19- swimming-advisories 39. 37. Westrick, J., Szlag, D., Southwell, B. and Sinclair, J. 28. Testai E, Scardala S, Vichi S, Buratti FM, Funari E (2010) A review of cyanobacteria and cyanotoxins (2016). Risk to human health associated with the removal/inactivation in drinking water treatment. Anal environmental occurrence of cyanobacterial Bional Chem, 397; 1705-1714. neurotoxic anatoxins and . Critical 38. World Health Organization (1999) Toxic reviews in toxicology. 46:385-419. Cyanobacteria in Water: A guide to their public health 29. US EPA (2007) International Symposium on consequences, monitoring and management. Edited by Cyanobacterial Harmful Algal Blooms (ISOC-HAB), Chorus, I. and Bartram, J. ISBN: 978-0-419-23930-7, Proceedings from the 2005 symposium. Available 416pp. Available online at: online at: http://www.who.int/water_sanitation_health/resources http://nheerlpub.rtord.epa.gov/nheerl/cyanobacteria_sy quality/toxicyanbact/en/ mposium/ 39. World Health Organization (2003) Guidelines for safe 11 recreational water environments. Volume 1, Coastal and fresh waters. ISBN 92 4 154580 1, 33pp. Available on line at: http://www.who.int/water_sanitation_health/bathing/sr we1/en/ 40. Zamyadi, A. et al (2012) Fate of toxic cyanobacterial cells and disinfection by-products formation after chlorination. Water Research, 46; 1524-1535. 41. Zamyadi, A. et al (2012) Toxic cyanobacterial breakthrough and accumulation in a drinking water plant: A monitoring and treatment challenge. Water Research, 46; 1511-1523.

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