Is nostoc a pathogen?

Nostoc is not typically classified as a pathogen for humans or animals. However, some species of nostoc can produce toxins under certain conditions, which can cause health issues if ingested or exposed to in large amounts. These toxins, such as microcystins, are more commonly a concern in aquatic ecosystems. In general, nostoc is not pathogenic in the traditional sense but can cause skin irritation or allergic reactions in some individuals upon direct contact.