A Quick Guide to the Common Cyanobacteria

of New England

The "Dirty Dozen" represents groups of commonly occuring cyanobacteria in New England. Various genera are grouped together here, due to their similiarity in shape. While there are some organisms that look morphologically similar, they vary significantly by genus and species. This list summarizes associated toxins and taste and odor issues by cyanobacteria noted from the literature. The toxins are not a comprehensive list of all reported toxins and there is some variation in toxin-genetics by colonies and species. The most commonly reported toxins are the microcystins, hepatotoxins that chronically affect the liver and may cause gastrointestinal issues. The taste and odor compounds produced by cyanobacteria have been mainly identifed as "geosmin" and "MIB", organic compounds with a distinctive "earthy" and "musty" taste and smell. Though there is not a clear distinctintion between cyanobacteria species that produce these compounds, taste and odor issues in drinking water supplies have been noted and described (below) from EPA reports. We will continue to research and expand our knowledge of known toxins and taste and odor compounds for these major groups of cyanobacteria as we develop this key further.

Click on the genus name for more information

Genus Groups

Photo Example

Associated (known) Toxins

Reported Taste & Odor Issues

1 Anabaena/Anabaenopsis anasm_icon anatoxin-a, microcystins "earthy, grassy, nasturium, musty"
2 Aphanizomenon aphaniz-sm-icon neosaxitoxin, microcystins "earthy, grassy, nasturium, musty, sweet"
3 Aphanocapsa/Aphanothece aphanoc-icon microcystins "earthy and musty"
4 Coelosphaerium coelo-icon microcystins "earthy and musty"
5 Gloeocapsa/Chroococcus gloeo-icon microcystins "grassy and sweet"
6 Gloeotrichia gloeotric-icon microcystins "grassy and sweet"
7 Lyngbya/Phormidium lyngbya-icon anatoxin, microcystins "earthy"
8 Merismopedia merismopedia-icon microcystins "earthy and musty"
9 Microcystis microcyst-icon microcystins "grassy and sweet"
10 Nostoc nostoc-icon BMAA, microcystins "musty, septic"
11 Oscillatoria/Planktothrix Osci-sm-icon microcystins "earthy, grassy, musty and spicy"
12 Woronichinia woron-sm-icon anatoxin, microcystins "earthy and musty"