Research conducted by scientists from the Warsaw University of Technology has shown the potential of Eisenia Fetida and Eisenia Andrei not only for remediating soils contaminated by a pipeline leak in Poland, but also those from Kuwait. The latter are a particular challenge. During Operation Desert Storm in 1991, 10 million tonnes of crude oil seeped into the soil, contaminating a large area of Kuwait. Despite the passage of time, remediation works are still being carried out on an unprecedented scale – the area requiring cleanup is about 300 km². It is the largest inland environmental cleanup operation, with an estimated cost of around USD 3 billion.

The mechanism of vermiremediation is simple yet highly effective: as earthworms move through the soil, they aerate it and mix it with humus, creating better conditions for microorganisms to break down contaminants. Moreover, microbes living in earthworms’ intestines can metabolise petroleum hydrocarbons. Thanks to this, toxins decompose and the soil gradually regains its natural properties. This method is attractive because it is relatively inexpensive and does not require complex equipment.

“Earthworms act as natural soil engineers,” emphasises Professor Małgorzata Kacprzak from the Faculty of Civil Engineering, Mechanics and Petrochemistry. “Their physical activity and intestinal microflora support the biodegradation of organic pollutants, including petroleum hydrocarbons. This is a promising path towards sustainable environmental cleanup.”

Despite promising results, the use of earthworms in soil remediation faces several challenges. First, the effectiveness of the process depends on the earthworm species and on the type and concentration of contaminants – not all pollutants are easily degradable. Second, extreme soil conditions, such as high salinity, lack of moisture, or very acidic pH, may limit the survival and activity of earthworms. In addition, scaling up laboratory experiments to industrial sites requires large numbers of organisms and careful monitoring of processes to avoid disruptions in the ecosystem.

Nevertheless, in the future these small soil engineers may become an important tool in combating environmental pollution and revitalising industrial areas.