Soil in Medicine

Soils can both challenge and support health

Soil can be used to make walls, bricks, and buildings - materials that may seem dry and lifeless. However, beyond its role in construction, soil is also one of the most biologically active habitats on Earth. A single gram can contain billions of microorganisms interacting in complex communities that affect ecosystems, plant health, and even human health.

Many people associate soil organisms with danger. In some cases, this is justified. One well-known example is tetanus, a serious bacterial infection caused by spores of Clostridium tetani. These bacteria can enter the body through open wounds, which is why proper wound care and tetanus vaccination are important.

Soil also contains organisms that cause plant diseases. One well-known example is Phytophthora infestans, a fungal pathogen associated with wet soils that causes potato and tomato blight. In the nineteenth century, it contributed to the Irish Potato Famine, demonstrating how strongly soil organisms can influence human societies and food security.

However, disease-causing organisms represent only a small fraction of soil life. In fact, scientists increasingly describe soil as a hidden pharmacy. Soil microorganisms constantly compete for space and resources, producing chemical compounds that inhibit or suppress one another.  Some of these compounds are now used in agriculture as biological control agents against crop diseases. As such, some microbes such as Trichoderma spp. are used in agriculture as biological control against crop diseases.

For sources and further information on soil - plant - human health relationships, we refer you to articles by Brevik et al. (2020), Wall et al. (2015), and Timmis & Ramos (2021). For more information on Trichoderma spp., you may read an article by Mukhopadhyay & Kumar (2020).