Harmful Algal Blooms at Surface Water Reservoirs. Stephanie A. Smith, Ph.D. September 18, 2014 NY AWWA Tift Symposium Liverpool, NY

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1 Harmful Algal Blooms at Surface Water Reservoirs Stephanie A. Smith, Ph.D. September 18, 2014 NY AWWA Tift Symposium Liverpool, NY

2 HABs Bloom overgrowth of algae, usually but not always visible Algae often not true algae, but rather are cyanobacteria, a.k.a. blue-green algae Harmful causing adverse ecological impacts and/or posing a potential threat to animal and human health Toxins are an obvious issue, but what about Anoxic conditions that kill fish Deaths of pets, livestock Taste and odor issues in drinking water Sludge disposal is it toxic? Economic damage at recreational lakes

3 Figure 3 Paerl & Paul (2012) Water Research 46:

4 Figure 4 Paerl & Paul (2012) Water Research 46:

5 5 Competitive advantages Growth at high temperature Buoyancy regulation Microcystis, Anabaena, Aphanizomenon, Planktothrix Nitrogen fixation Aphanizomenon, Nostoc, Cylindrospermopsin, Anabaena Toxin production?

6 It s Obvious, right? 6

7 Or is it? Photos courtesy of Steve Morton, NOAA

8 8 Or is it? P. rubescens and M. aeruginosa Heather Raymond, OH EPA, 2012 Suspected Planktothrix rubescens, but turned out to be Euglena Heather Raymond, OH EPA, 2012

9 9 Or is it? Lyngbya, Julie Letterhos Cylindrospermopsis, Heather Raymond Planktothrix, Linda Merchant-Masonbrink Ohio EPA accessed February 2013

10 10 HABs: The Toxins Cyanotoxins Hepatotoxins, neurotoxins, dermatoxins Acute or chronic One toxin can be made by multiple organisms One organism can make multiple toxins For any one toxin, there may be multiple structural types, or congeners

11 11 HABs: The toxins microcystin nodularin anatoxin saxitoxin Microcystin-LR cylindrospermopsin

12 The Toxins Toxin Organisms Target organ/system Microcystin Anatoxin Cylindrospermopsin Microcystis, Anabaena, Aphanizomenon, Anabaenopsis, Planktothrix Anabaena, Aphanizomenon, Cylindrospermopsis, Oscillatoria, Planktothrix Cylindrospermopsis, Aphanizomenon, Umezakia, Lyngbya, Rhaphidiopsis, Anabaena Liver Nervous system Liver Effects Abdominal pain, vomiting and diarrhea, liver inflammation, dermatitis, and more Neurotoxin; tingling, burning, numbness, drowsiness, slurred speech See MC

13 13 Toxin potency Cyanotoxin LD50 (ug/kg) Comparison Saxitoxins 10 Ricin 22 Anatoxin-a 200 Cobra venom 185 Anatoxin-a(S) 20 Sarin 218 Microcystin-LR 50 Curare 500 LD50 (ug/kg) Cylindrospermopsin 300/180 Strychnine 2500/980 Hudnell (2010), Toxicon 55:

14 Intracellular or Extracellular? Healthy cells making microcystin or anatoxin-a Healthy cells making cylindrospermopsin Dying cells release toxins of any type

15 What s a TPO to do? Define your goals For your source For your raw water intake For treatment Develop an approach to meet those goals Develop a contingency plan

16 Monitor Identify Phycocyanin, chlorophyll, turbidity, etc. Microscopy, to look for toxic vs. nontoxic taxa of algae Measure Manage Measure for algal toxins using test strips or ELISA Limit nutrients, algaecides, natural products

17 Monitoring Tools YOUR EYES! Turbidity Temperature ph Dissolved oxygen Filter backwash is it green? Taste & Odor in summer? Fluorescent pigments

18 Principles of Fluorescence Plants and green algae have chlorophyll Chlorophyll

19 Principles of Fluorescence Cyanobacteria (blue green algae) have phycocyanin + chlorophyll Phycocyanin Chlorophyll

20 Fluorometers Used in a wide range of applications microbiology, medical, WQ, molecular research, etc. Portable or Submersible Automated data logging Google image search handheld fluorometer YSI Google image search submersible fluorometer

21 Portable Fluorometers Measure, PC, Chl, or both Changes in pigment reflect changes in population Establish a baseline, and monitor for changes No magic cutoffs!

22 Identify: Microscopy Different types of microscopes with different features Classical compound light, inverted, phase contrast, fluorescence These are bacteria need X! Wide range in price Significant skill

23 Identify: Microscopy Oscillatoria Lyngbya

24 Identify: Microscopy Again, define your goals: Do you need full identification and enumeration of all taxa present, OR Do you just need to know if you have potentially toxic organisms to help decide whether you should test for toxins, OR Are you using this as a monitoring tool, and you are regularly looking for shifts in the population, OR Some combination of the above?

25 Monitor Identify Phycocyanin, chlorophyll, turbidity, etc. Microscopy, to look for toxic vs. nontoxic taxa of algae Measure Manage Measure for algal toxins using test strips or ELISA Limit nutrients, algaecides, natural products

26 Microcystin International Guidelines Country Limit Note Australia 1.3 ppb total microcystins Canada 1.5 ppb MC-LR MAC Czech Republic, China, Italy, Japan, Korea 1 ppb MC-LR, WHO provisional guidance New Zealand 1 ppb Addresses 5 other toxins Brazil 1 ppb Presumed total MC; has CYN and SAX guidelines, too Spain 1 ppb Total microcystins United State of America??????

27 Cyanotoxins are not regulated in the U.S. Safe Drinking Water Act requires USEPA to publish list of unregulated potential contaminants Contaminant Candidate List (CCL) #3 has Anatoxin-a Microcystin LR Cylindrospermopsin

28 Cyanotoxins are not regulated in the U.S. However 2014 ASDWA Survey, 34 states responding 5 have advisory thresholds for MC, 2 for additional toxins 6 have programs and policies, 4 have draft policies, 8 are discussing drafting policies General consensus the regulations will be coming

29 Holy Toledo! ADDA-ELISA detected >2 ppb in finished water USEPA, OEPA confirmatory testing with ELISA + LC/MS Is the WHO guideline the way to go, and if so, what does it actually mean?

30 Toxin Analyses High specificity Low sensitivity NMR TLC Bioassay LC/MS HPLC PPIA ELISA High sensitivity Low specificity

31 ELISAs For water, by far the most popular Considered a screening tool A handful of popular commercial kits Abraxis Beacon Modern Water Envirologix Enzo Life Sciences (Abraxis?)

32 ELISAs Some limitations Antibody binding to an analyte, so actually an indirect measurement Cross reactivity of those antibodies with other things (low specificity) What are the antibodies binding to?

33 Does ADDA add up? nodularin

34 Does ADDA add up? WHO guidelines and others were not based on ADDA or total microcystins, they were based on MC-LR, and LR only Does this matter? Are the microcystins all the same?

35 LD Toxicity Toxin LD 50 (µg/kg) Animal Route Reference MC-LR 43.0 Mouse i.p. Gupta et al., ± 9 Mouse i.v. Kondo et al., (reported as ng/g) Mouse i.p. Stoner et al., Mouse Oral Fawell et al., Mouse i.p. Fawell et al., 1999 >5000 Rat Oral Fawell et al., Rat (fed) i.p. Miura et al., Rat i.p. Miura et al., 1991 (fasted) 73 Mouse i.p. Watanabe et al., 1988 MC-YR Mouse i.p. Gupta et al., ± 2 Mouse i.v. Kondo et al., Mouse i.p. Watanabe et al., 1988 MC-RR Mouse i.p Gupta et al., Mouse i.p. Watanabe et al., (reported as ng/g) Mouse i.p. Stoner et al., 1989 MC-LA 39 (reported as ng/g) Mouse i.p. Stoner et al., 1989 MC-LY 91 (reported as ng/g) Mouse i.p. Stoner et al., 1989

36 Monitor Identify Phycocyanin, chlorophyll, turbidity, etc. Microscopy, to look for toxic vs. nontoxic taxa of algae Measure Manage Measure for algal toxins using test strips or ELISA Limit nutrients, algaecides, natural products

37 #1 Goal at the Source: Prevention Know your watershed, not just your water Preventing growth: Limit nutrient inputs Good aeration and mixing Flowing/movement of water Do copper or other treatments before the bloom? Preventing intake: Intake valves at different depths Rotation of reservoirs/more than one source

38 Manage the Source Copper is still the most popular Peroxide-based Alum treatment of reservoirs Is the toxin intra- or extra- cellular?

39 Intracellular or Extracellular? Healthy cells making microcystin or anatoxin-a Healthy cells making cylindrospermopsin Dying cells release toxins of any type

40 Treatment Intracellular toxin (Intact Cells) Removal Yay or Nay? Pretreatment oxidation Coag/Sediment/Filtration Membranes Flotation/DAF Oxidation processes Nay Yay Assumed Yay Yay Nay

41 Treatment Extracellular Toxin (waterborne) Removal Yay or Nay? Membranes Potassium Permanganate Ozone Chlorine dioxide Chloramines Chlorination UV Radiation GAC/PAC Maybe Yay for MC and Ana, not sure on CYN Yay for all Nay for acceptable DW doses Nay Yay for MC if ph is below 8, ineffective for Ana Yay, but really high doses Yay

42 Chlorination ph MC-LR CT values in (mg x min)/l ppb 10⁰C 15⁰C 20⁰C 25⁰C Acero et al 2005

43 Chlorination For MC: ph below 7 Saxitoxin, higher ph is better At ph 9 CT of 15 Cylindrospermopsin CT of 15 at phs above 6 Anatoxin-a is not degraded by chlorine However, byproducts may have some toxicity in the case of cylindrospermopsin Nicholson et al 2003; Senogles et al 2000; Carlile et al 1994; Shaw et al 2001

44 Carbon Generally effective for the extracellular toxins Challenge is disposal/regeneration Mesoporous for MC and CYN, micro for ANA

45 Management Must have a plan for response just like any contaminant or contingency plan Must have a plan for public outreach and communication Frazil ice example from OH very savvy usage of social media

46 In Summary There are tools for dealing with HABs: Monitor/Identify, Measure, and Manage From a drinking water perspective, being reactive, rather than proactively monitoring and managing, can have serious consequences

47 In Summary There needs to be consensus and leadership regarding how we handle HABs How to monitor and measure How to regulate/mitigate the causes How to build the foundation of understanding The situation we are in now reflects the paucity of research funding in this area for the last 25 years Reactionary funding does not solve problems!

48 Thank You