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HomeMy Public PortalAboutCyanobacteria Risk Categories 2022 Draft 3.25.22 Association to Preserve Cape Cod 1 March 25, 2022 Dear Cyano Program Partner: The Association to Preserve Cape Cod (APCC) is committed to providing the best possible information to the public about the presence and severity of cyanobacteria outbreaks in the Cape’s lakes and ponds. As a part of that effort, APCC has been attending meetings with the Cape and Islands Health Agents Coalition (C&I HAC) to expand the discussion of cyanobacteria monitoring and responses on Cape Cod. These meetings were also attended by our partners, which included cyanobacteria experts Nancy Leland, who is affiliated with the University of New Hampshire Center for Freshwater Biology, and Karen Malkus-Benjamin, former Coastal Health Agent for the town of Barnstable, and members of the Brewster Ponds Coalition. Our discussions centered on providing outreach to health agents concerning cyanobacteria risks, explaining the EPA and CyanoCasting cyanobacteria monitoring and analysis methods, discussing local and regional responses to cyanobacteria monitoring data, and communication of results to public officials and the public. In parallel with these meetings, APCC and the Barnstable County Department of Health and the Environment’s (BCDHE) Water Quality Lab began planning a new and important advancement in regional capability for cyanobacteria toxin testing. Beginning in 2022 as a complement to APCC’s well-established monitoring program, the BCDHE Water Quality Lab will expand its cyanobacteria toxin testing capabilities to provide local officials with precise toxin measurements from ponds pre-identified by APCC as potentially containing cyanobacteria toxin levels of concern. APCC’s proactive cyanobacteria monitoring data will be used to flag ponds that will receive confirmatory toxin testing by the BCDHE Water Quality Lab to determine whether an advisory is warranted. To ensure that samples for toxin testing are collected on the same date, time, and place as samples for cyanobacteria monitoring, APCC will collect GRAB samples for toxin analysis at the same time and location as our samples for cyanobacteria analyses. Samples for toxin analyses will be collected and preserved according to EPA protocols (Surface Water Sampling, Method 546). In the event that APCC’s cyanobacteria data indicate the potential for toxin levels of concern, the corresponding GRAB sample(s) will be sent to the County for toxin analysis. The County Water Quality lab will then pass on its results and recommendations to local officials and APCC. These results will supplement data collected and communicated by APCC. The simultaneous collection of samples for cyanobacteria and cyanotoxin will help to ensure that cyanotoxin analyses (if warranted) correspond to cyanobacteria monitoring data in terms of time and place. This proactive sampling approach will avoid a common pitfall of reactive sampling that can occur when cyanobacteria monitoring data are collected on one date and confirmatory samples are collected several days to a week later when conditions may have changed. APCC has listened to input and comments from health agents and other interest groups. The input we have heard has resulted in changes and improvements to our program highlighted by the new regional capability for toxin testing provided by the BCDHE Water Quality Lab. As new materials or information are produced by program partners, they will be considered for incorporation into the attached document. Sincerely, Andrew Gottlieb, Executive Director Kevin Johnson, Ecologist Jo Ann Muramoto, Ph.D., Director of Science Programs Association to Preserve Cape Cod 2 March 25, 2022 APCC 2022 Cyanobacteria Risk Categories for Communication of Results via Reports and the Interactive Map Introduction APCC’s Cyanobacteria Monitoring Program partners with officials at the town, county, state, and federal levels as well as local pond associations and residents to conduct cyanobacteria monitoring in Cape Cod ponds. Each season, data is collected biweekly and shared with local officials and the general public through reports, emails, and an interactive map of monitoring results found on our website (https://apcc.org/our-work/science/community- science/cyanobacteria/). Our goals are to raise public awareness of the health and ecological risks posed by cyanobacteria blooms, to help inform proper responses to cyanobacteria concerns in order to promote public health, to monitor priority ponds across the Cape, and to motivate public action to address the causes of harmful cyanobacteria blooms (HCB) by improving water quality. Cyanobacteria are an ancient group of photosynthetic microorganisms common in freshwater systems on Cape Cod and worldwide. Under the right conditions, they can multiply rapidly and form harmful cyanobacteria blooms. According to the Centers for Disease Control and Prevention, certain common cyanobacteria genera can produce toxins known as cyanotoxins that can be harmful to humans (CDC). HCBs have increased worldwide, including in the U.S., because of nutrient enrichment and rising water temperatures due to warming resulting from climate change. As HCBs are expected to increase, the need for increased cyanobacteria monitoring and awareness has never been greater. Cape Cod ponds are commonly heavily used for swimming, boating, paddle boarding, and fishing. Due to the increasing prevalence of HCBs and the resulting increased threat of public exposure to cyanobacteria, the Massachusetts Department of Public Health (MDPH) has guidelines for municipal officials to post and remove advisories at ponds for established thresholds for cyanobacteria concerns (MDPH). Frequent cyanobacteria monitoring of ponds provides the data for resource managers to track cyanobacteria trends in their ponds throughout the season, apply relevant public health criteria, and to be proactive about posting and removing recreational advisories. APCC’s cyanobacteria monitoring program provides scientifically sound data on cyanobacteria composition, concentrations, and predicted toxin concentrations. Our program uses and follows the EPA’s Quality Assurance Project Plan (QAPP) for cyanobacteria monitoring, developed by EPA for the Cyanobacteria Monitoring Collaborative or CMC (CMC QAPP). The QAPP was developed by EPA Region 1 scientists, including Hillary Snook and others, with the goal of encouraging and facilitating widespread monitoring of cyanobacteria. The QAPP is based on Association to Preserve Cape Cod 3 March 25, 2022 methods created by EPA scientists and other cyanobacteria specialists, including Dr. Jim Haney and Nancy Leland with the University of New Hampshire Center for Freshwater Biology. The method involves taking concentrated samples of “Bloom Forming Colonies” (BFCs) through a 3- meter student plankton net tow and unconcentrated samples of “Whole Lake Water” (WLW) through a meter integrated tube. APCC also utilizes the CyanoCasting method developed by Nancy Leland (Leland, 2018), which builds on the methods described in the QAPP by including metrics that allow for the forecasting of potential imminent cyanobacteria blooms. The forecasting ability of this method provides valuable advance warnings of potential HCBs to inform proactive responses, such as increased frequency of specific toxicity testing or precautionary advisories and postings of ponds to warn the public of imminent cyanobacteria blooms. The ability to predict and anticipate potential HCBs based on frequent monitoring is a unique and valuable feature of APCC’s program and stands in contrast to reactive responses involving measurement of cyanobacteria concentrations after a bloom has occurred (Leland et al. 2018, Leland et al 2019). Massachusetts Department of Public Health (MDPH) Guidelines for Cyanobacteria The MDPH cyanobacteria webpage describes guidelines for cyanobacteria in recreational freshwater bodies that are described as follows (“Guidelines for Cyanobacteria at Recreational Freshwater Locations”) (MDPH). “DPH recommends issuing a public health advisory for HABs at recreational freshwater locations when at least one of the following criteria is met: 1. A visible cyanobacteria scum or mat is evident. 2. Total cell count of cyanobacteria exceeds 70,000 cells/mL. 3. Concentration of the toxin microcystins exceeds 8 µg/L; or 4. Concentration of the toxin cylindrospermopsin exceeds 15 µg/L Guideline values are based on US Environmental Protection Agency (US EPA) and World Health Organization (WHO 1999) (WHO 2003) recommendations. When issuing an advisory, signage should be posted at each access point at the waterbody warning against any contact with the water. Rescinding a Public Health Advisory Cyanobacteria cells can release cyanotoxins into the water when they die. Therefore, algal toxins may be present when a visible scum or mat is no longer evident. DPH recommends the rescinding of a public health advisory after two successive samples, collected a week apart, demonstrate cell counts or toxin levels below the quantitative guideline values.” (MDPH). APCC Cyanobacteria Risk Communication in 2022 APCC’s updated method of communicating and interpreting results will no longer be referred to as “Warning Tiers,” but rather “Cyanobacteria Risk Categories” comprised of three categories: “Acceptable,” “Potential for Concern,” and “Use Restriction Warranted.” Association to Preserve Cape Cod 4 March 25, 2022 The “Acceptable” category will be applied to ponds where no concerning results are found and APCC deems that additional toxin testing will not be necessary based on our monitoring results. The “Potential for Concern” category will be applied to ponds where concerning results or trends are found that could serve as an early warning of cyanobacteria risks. APCC will send samples in this category to the BCDHE Water Quality Lab for confirmatory toxin testing. A “Pet Advisory” may also be warranted for ponds in this category. APCC has developed the criteria for these two categories with recommendations from Karen Malkus-Benjamin, former Coastal Health Agent for the town of Barnstable, and Nancy Leland to distinguish between ponds with safe results requiring no additional toxin testing and potentially concerning results requiring additional toxin testing. The “Use Restriction Warranted” category will be applied to ponds where results exceed one or more of the following four criteria: criteria for microcystin based on MDPH guidance, criteria for cyanobacteria scum layers based on MDPH guidance, criteria for anatoxin-a based on the draft Health Agent Guide, or where the health agent has already posted an advisory for cyanobacteria. Ponds that are placed in this category warrant posting of a recreational use advisory by health agents and will be marked in red on APCC’s map. Ponds in this category will be sampled weekly and APCC will continue to send samples to the BCDHE Water Quality Lab for confirmatory toxin testing until the pond is deemed safe to reopen or the advisory is removed. Use Restrictions and Advisories Use restrictions and advisories are issued at the discretion of the municipal health agents. As of this writing, there is no commonly utilized set of guidelines in use for health agents across the Cape that provides consistency in posting criteria. As a result, members of the public are advised to contact the health agent in each town (see the contact list provided on APCC’s website) to determine the official status of the pond about which they are interested. While ponds exceeding MDPH standards as discussed above will be marked in red, this coloration does not always mean a use restriction has been issued by the town. APCC will update our list of restricted ponds as we are informed by the respective towns, but APCC does not speak for the towns unless otherwise and explicitly noted on our posting map. As part of the C&I HAC meetings, former Barnstable coastal health agent Karen Malkus- Benjamin developed the Cyanobacteria Health Agent Guide (2022) to assist health agents in decision making for cyanobacteria advisory responses based on data. While the Health Agent Guide remains in draft form and has not yet been formally adopted, APCC encourages the C&I HAC to review, adopt, and implement the guide. The draft Health Agent Guide is included as Attachment 1 to provide information to health agents and APCC partners. Further updates to this draft guide may be adopted by the C&I HAC, and APCC guidance will be updated to reflect any such action. APCC’s risk categories are closely tied to the current draft of the Health Agent Guide. However, an important difference between APCC’s risk categories and the categories in the Health Agent Guide is that the latter includes three nuances of recreational advisory postings including “Warning,” “Swimming Beach Closure,” and “Pond Closure,” whereas APCC only has one such Association to Preserve Cape Cod 5 March 25, 2022 category, “Use Restriction Warranted.” APCC’s “Potential for Concern” category roughly equates to the “Pet Advisory” as both indicate that concerning results are still below concern thresholds for standard human advisory notices. For simplicity in communication, APCC will use the “Use Restriction Warranted” category to include all recreational advisory postings. APCC’s recommendations for removing a recreational use advisory will mirror the reopening guidance from the draft Health Agent Guide. For a microcystin toxin exceedance or bloom, APCC will recommend lifting a recreational use advisory or closure after two consecutive weekly tests contain microcystin concentrations less than 8 parts per billion (ppb) and no presence of cyanobacteria bloom material. For an anatoxin-a toxin exceedance or bloom, APCC will recommend a recreational use advisory or closure be lifted the week following an exceedance if anatoxin-a concentrations are below 10 ppb and there is no evidence of cyanobacteria bloom material.1 Health agents are solely responsible for the issuance and removal of recreational use advisories or closures related to water clarity. Cyanobacteria Risk Categories Discussion Using these updated risk categories, APCC will interpret our monitoring results to inform health agents and the public of when cyanobacteria conditions are deemed safe (Acceptable), when cyanobacteria trends are becoming concerning (Potential for Concern), and when an advisory is warranted (Use Restriction Warranted). All specific criteria for these categories are included in Table 1 at the end of this document. The criteria for these categories do not include cell counts or cylindrospermopsin, as neither APCC nor the BCDHE Water Quality Lab has the capacity to test for these metrics. To assign a Cyanobacteria Risk Category to a pond for a given monitoring period, the most hazardous result among multiple criteria will determine the category in which the pond is placed. A pond that meets even a single criterion in the “Use Restriction Warranted” category will placed in that category. Likewise, a pond that meets even a single criterion in the “Potential for Concern” category, but does not meet any criteria in the “Use Restriction Warranted” category, will be placed in the “Potential for Concern” category. If a pond meets no criteria in the “Use Restriction Warranted” or the “Potential for Concern” categories, that pond is placed in the “Acceptable” category. All descriptions and criteria for these categories are summarized in the table and discussed below. APCC Cyanobacteria Risk Categories Acceptable Definition: No concerning cyanobacteria results at the time and place of sampling. To the best of our knowledge and based on our monitoring results, regular recreational usage of the pond is safe with respect to cyanobacteria and toxins. Map color is blue. Formerly the Low Warning Tier1. Recommended Sampling Frequency: Biweekly. Recommended Action: APCC will continue biweekly monitoring. Potential for Concern Association to Preserve Cape Cod 6 March 25, 2022 Definition: Monitoring results at the time and place of sampling indicate either moderate risk for potential exposure to cyanobacteria toxins or a likelihood for higher cyanobacteria risks in the near future. While these conditions pose low health risks to adults, risks are higher for children or pets, particularly if contaminated water is incidentally ingested. Children may inadvertently consume pond water while swimming and pet exposure can result from directly drinking pond water or from grooming after swimming. Due to lower body masses, children and pets are more susceptible to cyanobacteria risks than adults. A “Pet Advisory” may be posted at public access points. Map color is yellow. Formerly the Moderate Warning Tier1,2. Recommended Sampling Frequency: Weekly. Recommended Action: 1. Samples should be analyzed for cyanotoxins by the BCDHE Water Quality Lab. APCC or the town will provide a GRAB sample and, if available, a SCUM sample to the BCDHE Water Quality Lab. If the sample is Microcystis spp. dominant, test for microcystin. If the sample is Dolichospermum spp. dominant, test for anatoxin-a. If the sample is dominated by a different genus or is a mixed assemblage, test for both. 2. Post a “Pet Advisory” or similar advisory according to municipal policies and procedures until the pond is once again Acceptable. Use Restriction Warranted Definition: Monitoring results at the time and place of sampling indicate a high risk for potential exposure to cyanobacteria toxins, based on one or more of the following criteria: 1) presence of microcystin according to MDPH guidance, 2) presence of cyanobacteria scum layers according to MDPH guidance, 3) presence of anatoxin-a according to the draft Health Agent Guide, or 4) a municipal health agent issues a closure for any other reason related to cyanobacteria. Recreational risk to adults is moderate following exposure. Recreational risks are especially high for children and pets following exposure through accidental ingestion of contaminated water. Children may inadvertently consume pond water while swimming and pet exposure can result from directly drinking pond water or from grooming after swimming. Due to lower body masses, children and pets are more susceptible to cyanobacteria risks than adults. A “Use Restriction Advisory” has been recommended for public access points. Map color is red based on the application of the following criteria: County sample for microcystin exceeds 8 ppb or for anatoxin-a exceeds 10 ppb; presence of a visible scum in excess of MDPH guidelines, or if a municipal health agent issues a closure for any other reason related to cyanobacteria. Formerly the High Warning Tier1,2,3. Recommended Sampling Frequency: Weekly. Recommended Action: 1. Samples should be analyzed for cyanotoxins by the BCDHE Water Quality Lab. APCC or the town will provide a GRAB sample and, if available, a SCUM sample to the BCDHE Water Quality Lab. If the sample is Microcystis spp. dominant, test for microcystin. If the sample is Dolichospermum spp. dominant, test for anatoxin-a. If the sample is dominated by a different genus or is a mixed assemblage, test for both. 2. Post a “Use Restriction Advisory” or similar advisory according to municipal policies and procedures and otherwise notify the public to avoid contact and exposure until the pond completes the criteria to be reopened or for the advisory to be removed by the local health agents. Association to Preserve Cape Cod 7 March 25, 2022 APCC 2022 Cyanobacteria Risk Categories Table of Criteria APCC 2022 Cyanobacteria Risk Categories Criteria APCC Acceptable APCC Potential for Concern Use Restriction Warranted Microcystin Predicted microcystin by APCC. Less than or equal to 8 ppb microcystin predicted in APCC’s BFC (bloom- forming colonies) sample4. Greater than 8 ppb microcystin predicted in APCC’s BFC sample4. Measured microcystin by County. Less than 4 ppb microcystin measured in GRAB or SCUM sample. Between or equal to 4 and 8 ppb microcystin measured in GRAB or SCUM sample. Greater than 8 ppb microcystin measured in GRAB or SCUM sample3. Cyanobacteria Biomass Cyanobacteria growth rate calculated by APCC. Less than 0.07 in all APCC samples1,2,4. Greater than or equal to 0.07 in any APCC sample1,2,4. Cyanobacteria bloom material confirmed by APCC. None present at the time and place of sample collection. A slight cyanobacteria scum or small patches of cyanobacteria bloom material sampled and confirmed1. Significant cyanobacteria scum or large patches of cyanobacteria bloom material sampled and confirmed1,3. Anatoxin-a Measured Anatoxin-a by County. Less than 4 ft of visibility for any pond with elevated pico- cyanobacteria concerns2. Greater than or equal to 10 ppb Anatoxin-a measured in GRAB or SCUM sample1. Notes To interpret cyanobacteria data using this table, the most hazardous result determines the category the pond is placed in from right to left. A pond that meets even a single criterion in the “Use Restriction Warranted” column will placed in that category. Likewise, a pond that meets even a single criterion in the “APCC Potential for Concern” category, but does not meet any criteria in the “Use Restriction Warranted” category, will be placed in the “APCC Potential for Concern” category. If a pond meets no criteria in the “Use Restriction Recommended” or the “APCC Potential for Concern” category, that pond is placed in the “APCC Acceptable” category. 1 Developed with recommendations from cyanobacteria expert Karen Malkus-Benjamin, former Coastal Health Agent for the Town of Barnstable. 2 Developed with recommendations from cyanobacteria expert Nancy Leland affiliated with the University of New Hampshire Center for Freshwater Biology. 3 Criteria attributed to MDPH. 4 Predictive cyanobacteria metrics that project and estimate risks, rather than reactive cyanobacteria metrics that measure risk after a bloom has occurred. Table 1. APCC 2022 Cyanobacteria Risk Categories Table of Criteria. Association to Preserve Cape Cod 8 March 25, 2022 Footnotes 1 Developed with recommendations from cyanobacteria expert Karen Malkus-Benjamin, former Coastal Health Agent for the Town of Barnstable. 2 Developed with recommendations from cyanobacteria expert Nancy Leland affiliated with the University of New Hampshire Center for Freshwater Biology. 3 Criteria attributed to MDPH. 4 Predictive cyanobacteria metrics that project and estimate risks, rather than reactive cyanobacteria metrics that measure risk after a bloom has occurred. Work Cited Centers for Disease Control and Prevention (CDC) webpage on “Harmful Algal Bloom (HAB)- Associated Illness”. https://www.cdc.gov/habs/general.html Leland, N.J. 2018. Fundamentals of Cyano-casting: cost-effective monitoring techniques for cyanobacteria surface blooms and cyanotoxin levels. In cooperation with UNH Center for Freshwater Biology. http://lim-tex.com/wp- content/uploads/2018/05/CyanoCasting_Handbook_v18.pdf Leland, N.J. and Haney, J.F., 2018. Alternative Methods for Analysis of Cyanobacterial Populations in Drinking Water Supplies: Fluorometric and Toxicological Applications Using Phycocyanin. Journal of Water Resource and Protection, 10, 740-761. Posted at: https://www.scirp.org/journal/PaperInformation.aspx?paperID=86671& Leland, N.J., J.F. Haney, K. Conte, K. Malkus-Benjamin and B. Horsley. 2019. Evaluation of size structure in freshwater cyanobacteria populations: methods to quantify risk associated with changes in biomass and Microcystin concentrations. Journal of Water Research and Protection, 2019, 11, 810-829. Posted at: https://www.scirp.org/journal/paperinformation.aspx?paperid=93424 Leland, N.J., R. A. Landon, and J.F. Haney. September 2020. Trophic interactions between anadromous juvenile Alewife (Alosa pseudoharengus) and cyanobacterial populations in a shallow mesotrophic pond. Natural Resources, 2020, 11, 394-419. Posted at: https://m.scirp.org/papers/102960 . Malkus-Benjamin, Karen. 2022. Cyanobacteria Health Agent Guide. Draft (see Attachment 1). Massachusetts Department of Public Health (MDPH) website on “Guidelines for cyanobacteria at recreational freshwater locations”. https://www.mass.gov/info-details/guidelines-for- cyanobacteria-at-recreational-freshwater-locations U.S. EPA (United States Environmental Protection Agency) (2021). Surface Water Sampling. https://www.epa.gov/sites/default/files/2017- 07/documents/surface_water_sampling201_af.r4.pdf?VersionId=UWp.tCIlmVPv9SW6xeJX5Zi 7NCqtdNhZ Association to Preserve Cape Cod 9 March 25, 2022 U.S. EPA (United States Environmental Protection Agency) (2019). Recommended Human Health Recreational Ambient Water Quality Criteria or Swimming Advisories for Microcystins and Cylindrospermopsin. EPA-822-R-19-001 (PDF). www.epa.gov/sites/default/files/2019-05/documents/hh-rec-criteria-habs-document-2019.pdf U.S. EPA (Environmental Protection Agency). 2017, revised 2021. Cyanobacteria Monitoring Collaborative Program (CMC). Quality Assurance Program Plan (QAPP) for the Cyanobacteria Monitoring Collaborative Program. Rev: 0, April 26, 2017: Posted at: https://cyanos.org/wp- content/uploads/2017/04/cmc_qapp_final.pdf. U.S. EPA (Environmental Protection Agency). 2016. Method 546: Determination of Total Microcystins and Nodularins in Drinking Water and Ambient Water by Adda Enzyme-Linked Immunosorbent Assay. https://www.epa.gov/sites/default/files/2016-09/documents/method-546- determination-total-microcystins-nodularins-drinking-water-ambient-water-adda-enzyme-linked- immunosorbent-assay.pdf World Health Organization. 1999. Toxic cyanobacteria in water: a guide to their public health consequences, monitoring and management. https://www.who.int/water_sanitation_health/resourcesquality/toxcyanbegin.pdf WHO (World Health Organization) (2003). Guidelines for Safe Recreational Water Environments, Volume 1: Coastal and Fresh Waters. (PDF) http://apps.who.int/iris/bitstream/handle/10665/42591/9241545801.pdf?sequence=1