Cyanobacterial Harmful Algal Blooms: Chapter 15: Cyanotoxins Workgroup Report (original) (raw)
Related papers
Toxins, 2015
Human health risks from cyanobacterial blooms are primarily related to cyanotoxins that some cyanobacteria produce. Not all species of cyanobacteria can produce toxins. Those that do often do not produce toxins at levels harmful to human health. Monitoring programs that use identification of cyanobacteria genus and species and enumeration of cyanobacterial cells as a surrogate for cyanotoxin presence can overestimate risk and lead to unnecessary health advisories. In the absence of federal criteria for cyanotoxins in recreational water, the Oregon Health Authority (OHA) developed guideline values for the four most common cyanotoxins in Oregon's fresh waters (anatoxin-a, cylindrospermopsin, microcystins, and saxitoxins). OHA developed three guideline values for each of the cyanotoxins found in Oregon. Each of the guideline values is for a specific use of cyanobacteria-affected water: drinking water, human recreational exposure and dog recreational exposure. Having cyanotoxin guidelines allows OHA to promote toxin-based monitoring (TBM) programs, which reduce the number of health advisories and focus advisories on times and places where actual, rather than potential, risks to health exist. TBM allows OHA to more efficiently protect public health while reducing burdens on local economies that depend on water recreation-related tourism.
Advances in Experimental Medicine and Biology
Cyanobacteria are the oldest life forms on earth known to produce a broad spectrum of secondary metabolites. The functions/advantages of most of these secondary metabolites (peptides and alkaloids) are unknown, however, some of them have adverse effects in humans and wildlife, especially when ingested, inhaled or upon dermal exposure. Surprisingly, some of these cyanobacteria are ingested voluntarily. Indeed, for centuries mankind has used cyanobacteria as a protein source, primarily Spirulina species. However, recently also Aphanizomenon flos-aquae are used for the production of so called blue green algae supplements (BGAS), supposedly efficacious for treatment of various diseases and afflictions. Unfortunately, traces of neurotoxins and protein phosphatases (inhibiting compounds) have been detected in BGAS, making these health supplements a good example for human exposure to a mixture of cyanobacterial toxins in a complex matrix. The discussion of this and other possible exposure scenarios, e.g. drinking water, contact during recreational activity, or consumption of contaminated food, can provide insight into the question of whether or not our current risk assessment schemes for cyanobacterial blooms and the toxins contained therein suffice for protection of human health.
Chapter 3: Occurrence of Cyanobacterial Harmful Algal Blooms Workgroup Report
2000
Agency. Thanks are also due to Dr. Jeffrey Johansen of John Carroll University for his review and revisions to the Section 4 discussion of the current status of taxonomy of cyanobacteria. Special thanks to the workshop co-chairs: Jim Sinclair, PhD, US Environmental Protection Agency, Office Water, Cincinnati, Ohio and Sherwood Hall, PhD, Food and Drug Administration, CFSAN, Laurel, Maryland, who co-managed the process of preparing the manuscript. rine resources, fish and shellfish harvests and recreational and service industries along US coastal waters. In 2004, as part of its reauthorization, HABHRCA requires federal agencies to assess CHABs to include freshwater and estuarine environments and develop plans to reduce the likelihood of CHAB formation and to mitigate their damage (NOAA 2004). Many federal agencies recognize the potential impacts of CHABs and share risk management responsibilities; an interagency task force was established and charged to prepare a scientific assessment of the causes, occurrence, effects and economic costs of freshwater. The United States Environmental Protection Agency (EPA) has included "cyanobacteria (bluegreen algae), other freshwater algae, and their toxins" in its Contaminant Candidate List (CCL) as one of the microbial drinking water contaminants targeted for additional study, but it does not specify which toxins should be targeted for study (EPA 2005b). Based on toxicological, epidemiology and occurrence studies, the EPA Office of Ground Water and Drinking Water has restricted its efforts to 3 of the over 80 variants of cyanotoxins reported, recommending that Microcystin (MC) congeners LR, YR, RR and LA, Anatoxin-a (AA) and Cylindrospermopsin (CY) be placed on the Unregulated Contaminant Monitoring Rule (UCMR) (EPA 2001). The EPA uses the UCMR program to collect data for contaminants suspected to be present in drinking water that do not have health-based standards set. This monitoring supplies information on the nature and size of populations exposed to cyanotoxins through tap water use. Various federal agencies are mandated to address CHABs and their impacts, which commonly have been managed on a case-by-case, somewhat fragmented basis. A new national US plan, the Harmful Algal Research and Response National Environmental Science Strategy (HARNESS), is "designed to facilitate coordination by highlighting and justifying the needs and priorities of the research and management communities and by suggesting strategies or approaches to address them" (HARNESS 2005). CHABs cross all four critical areas identified for harmful algal research and response: bloom ecology and dynamics; toxins and their effects; food
Occurrence of Cyanobacterial Harmful Algal Blooms Workgroup Report
Advances in Experimental Medicine and Biology
Agency. Thanks are also due to Dr. Jeffrey Johansen of John Carroll University for his review and revisions to the Section 4 discussion of the current status of taxonomy of cyanobacteria. Special thanks to the workshop co-chairs: Jim Sinclair, PhD, US Environmental Protection Agency, Office Water, Cincinnati, Ohio and Sherwood Hall, PhD, Food and Drug Administration, CFSAN, Laurel, Maryland, who co-managed the process of preparing the manuscript. rine resources, fish and shellfish harvests and recreational and service industries along US coastal waters. In 2004, as part of its reauthorization, HABHRCA requires federal agencies to assess CHABs to include freshwater and estuarine environments and develop plans to reduce the likelihood of CHAB formation and to mitigate their damage (NOAA 2004). Many federal agencies recognize the potential impacts of CHABs and share risk management responsibilities; an interagency task force was established and charged to prepare a scientific assessment of the causes, occurrence, effects and economic costs of freshwater. The United States Environmental Protection Agency (EPA) has included "cyanobacteria (bluegreen algae), other freshwater algae, and their toxins" in its Contaminant Candidate List (CCL) as one of the microbial drinking water contaminants targeted for additional study, but it does not specify which toxins should be targeted for study (EPA 2005b). Based on toxicological, epidemiology and occurrence studies, the EPA Office of Ground Water and Drinking Water has restricted its efforts to 3 of the over 80 variants of cyanotoxins reported, recommending that Microcystin (MC) congeners LR, YR, RR and LA, Anatoxin-a (AA) and Cylindrospermopsin (CY) be placed on the Unregulated Contaminant Monitoring Rule (UCMR) (EPA 2001). The EPA uses the UCMR program to collect data for contaminants suspected to be present in drinking water that do not have health-based standards set. This monitoring supplies information on the nature and size of populations exposed to cyanotoxins through tap water use. Various federal agencies are mandated to address CHABs and their impacts, which commonly have been managed on a case-by-case, somewhat fragmented basis. A new national US plan, the Harmful Algal Research and Response National Environmental Science Strategy (HARNESS), is "designed to facilitate coordination by highlighting and justifying the needs and priorities of the research and management communities and by suggesting strategies or approaches to address them" (HARNESS 2005). CHABs cross all four critical areas identified for harmful algal research and response: bloom ecology and dynamics; toxins and their effects; food
Toxins produced in cyanobacterial water blooms - toxicity and risks
Interdisciplinary Toxicology, 2009
Cyanobacterial blooms in freshwaters represent a major ecological and human health problem worldwide. This paper briefly summarizes information on major cyanobacterial toxins (hepatotoxins, neurotoxins etc.) with special attention to microcystins -cyclic heptapeptides with high acute and chronic toxicities. Besides discussion of human health risks, microcystin ecotoxicology and consequent ecological risks are also highlighted. Although significant research attention has been paid to microcystins, cyanobacteria produce a wide range of currently unknown toxins, which will require research attention. Further research should also address possible additive, synergistic or antagonistic effects among different classes of cyanobacterial metabolites, as well as interactions with other toxic stressors such as metals or persistent organic pollutants.
Cyanobacterial toxins: risk management for health protection
This paper reviews the occurrence and properties of cyanobacterial toxins, with reference to the recognition and management of the human health risks which they may present. Mass populations of toxin-producing cyanobacteria in natural and controlled waterbodies include blooms and scums of planktonic species, and mats and biofilms of benthic species. Toxic cyanobacterial populations have been reported in freshwaters in over 45 countries, and in numerous brackish, coastal, and marine environments. The principal toxigenic genera are listed. Known sources of the families of cyanobacterial toxins (hepato-, neuro-, and cytotoxins, irritants, and gastrointestinal toxins) are briefly discussed. Key procedures in the risk management of cyanobacterial toxins and cells are reviewed, including derivations (where sufficient data are available) of tolerable daily intakes (TDIs) and guideline values (GVs) with reference to the toxins in drinking water, and guideline levels for toxigenic cyanobacteria in bathing waters. Uncertainties and some gaps in knowledge are also discussed, including the importance of exposure media (animal and plant foods), in addition to potable and recreational waters. Finally, we present an outline of steps to develop and implement risk management strategies for cyanobacterial cells and toxins in waterbodies, with recent applications and the integration of Hazard Assessment Critical Control Point (HACCP) principles. D
Journal of Microbiology, 2013
Fig. 1. The increasing trend of published scientific studies about toxic cyanobacteria worldwide. The key words used for searching in database [Web of Science (SCI & SSCI), PubMed and National Library of Medicine] were 'toxic cyanobacteria', 'harmful algal bloom', 'HAB', 'harmful algae', 'cyano HAB' and 'toxic blue-green algae' with EndNote (X4, Thomson Reuters). Journal articles and books were included. It should be noted that the census for 2012 publications was done as of November 2012, so it may underestimate the actual number accumulated by the end of 2012. Cyanobacteria have adapted to survive in a variety of environments and have been found globally. Toxin-producing cyanobacterial harmful algal blooms (CHABs) have been increasing in frequency worldwide and pose a threat to drinking and recreational water. In this study, the prevalence, impact of CHABs and mitigation efforts were reviewed, focusing on the Lake Erie region and Ohio's inland lakes that have been impacted heavily as an example so that the findings can be transferrable to other parts of the world that face the similar problems due to the CHABs in their freshwater environments. This paper provides a basic introduction to CHABs and their toxins as well as an overview of public health implications including exposure routes, health effects, and drinking water issues, algal bloom advisory practices in Ohio, toxin measurements results in Ohio public water supplies, and mitigation efforts.
Cyanobacteria Harmful Algae Blooms: Causes, Impacts, and Risk Management
2023
habitats, they are equally capable of secreting toxins, which altogether present grave environmental and medical consequences. In this paper, we gave an update on factors that influence cHABs, cyanotoxin exposure routes, and environmental public health implications, especially impacts on fish, pets, and livestock. We discussed social economic impacts, risk assessment, and management problems for cHABs and, thereafter, assessed the extant management approaches including prevention, control, and mitigation of the proliferation of cyanobacterial blooms. In light of this, we suggest that more intensified research should be directed to the standardization of procedures for cyanotoxin analysis. Also, the provision of standardized reference material for the quantification of cyanotoxins is vital for routine monitoring as well as the development of strong in situ sensors capable of quantifying and detecting HABs cells and toxins in waterbodies to prevent the adverse impacts of cHABs. Also, more investigations into the natural and environmentally friendly approach to cyanobacteria management and the necessary and appropriate deployment of artificial intelligence are required. Finally, we wish to redirect the focus of public health authorities to protecting drinking water supply sources, agriculture products, and food sources from cyanotoxins contamination as well as to implement proper monitoring and treatment procedures to protect citizens from this potential health threat.