SBE Professor Adria Elskus Published New USGS Fungicide Report

Adria Elskus works for the United States Geological Survey (USGS) whose purpose is to provide scientific understanding about natural resource conditions, issues, and problems. In its surveys, the USGS found fungicides in US surface waters that could affect valuable native fungi as well as other aquatic organisms. However, there is little information on the effects of fungicides on non-target aquatic organisms, and Elskus was asked to gather information on those fungicides USGS detected most frequently, have high or increasing global use, or are likely to persist in the environment.

Fungicides are a type of pesticide used to kill unwanted fungi and are used heavily in agriculture. New types of fungicides are produced regularly because fungi can develop resistance to them quickly. Unlike herbicides and insecticides that are sprayed on plants at certain times of the year, fungicides are applied when habitats are damp. Studying fungicides is increasingly important due to the potential for climate change to make some areas warmer and wetter, including Maine, increasing the use of fungicides.

Elskus summarized data on the specific environmental consequences of fungicides on organisms inhabiting aquatic environments. Insecticides on the one hand, can target an insect’s nervous system but fungicides have to target the most basic cell processes like mitosis and RNA transcription because fungi are so simple, being single celled organisms. Many organisms such as fish, birds and mammals, as well as invertebrates like clams and water fleas all share these same biological processes, and therefore could be harmfully affected by fungicides.

Native fungi may also be susceptible to these fungicides. Native fungi in streams break down leaves allowing bacteria to come in and break down the leaves even more to get nutrients into the streams and allow for healthy nutrient cycling.

Elskus’ report identifies a broad range of significant sub-lethal effects of fungicides on aquatic organisms and ecosystems, indicates the biochemical mechanisms where known, and points out where further research is needed.  Her report is entitled: ‘Toxicity, Sublethal Effects, and Potential Modes of Action of Select Fungicides on Freshwater Fish and Invertebrates’ and can be accessed by going to