Spectral Analysis of Earthworm Coelomic Fluid for Detecting Heavy Metals in Soil

Soil contamination by heavy metals poses a long term threat to ecosystems, especially to soil dwelling organisms. This study explores the use of earthworm (Lumbricus rubellus) coelomic fluid as a non-destructive bioindicator for detecting heavy metal contamination. Groups of earthworms were exposed to Zn, Cu, and a combination of both metals under controlled conditions. Ultraviolet light was used to excite the fluid, and the AS7262 sensor was used to observe six visible wavelengths. Differences in reflectance patterns helped differentiate between each type of metal contamination. ANOVA confirmed statistically significant differences in the orange, green, and yellow bands, indicating their sensitivity to the presence of metals. These results support the potential of coelomic fluid spectroscopy as a cost effective and reliable method for environmental monitoring.