Tiffany, I would not use the term "danger" when describing any lawn disease/pest. This stuff is simply unsightly, prevents grass growth where these patches grow, and are something that you definitely would not want to walk on. Think of these patches, which may be several feet in diameter, as masses of gooey, slimy mold/algae.
When I refer to "experimental chemical", understand that this chemical is generally available for many uses, and may have been around for many decades. This might be a chemical used for other purposes, and thus the use on this mold/algae may simply be "off-label" use. And further, this is something being done by a university-based, horticultural expert, someone who has a PhD in plant pathology. It is not quite like someone just coming off of the street and applying a poison!
