The effect of formalin fixed specimen disposal by burial on earthworm

Formalin is widely used for preservation of surgical and anatomical specimens in hospitals and medical laboratories. Formaldehyde (CH2O) is a water soluble, pungent, colourless and highly reactive gas. 40% solution of formaldehyde in water or solvent is known as formalin. Though the toxicology and the adverse effects of formaldehyde on human have been explained in details elsewhere, the effect on the environment is still considered very limited. This study was to identify the impact of formalin exposure towards earthworms by observing their reaction in different formalin concentration. A series of standard solution was prepared from 1000 ppm formaldehyde stock solution and the absorbance of formalin in the earthworms was recorded by using UV-Vis spectrophotometer. Results from this study showed the negative impact on earthworm caused by the formalin. When the formalin made contact with earthworm, the earthworms will expulse to the surface of soil. Expulsion of earthworm onto the surface will make the earthworm vulnerable to its predator, for instance, ants and birds. Moreover, the higher the concentration of the formalin exposure to earthworm, the faster earthworm will die. Formaldehyde can rapidly degrade air, water and soil. It also does not bio-accumulate under environmental conditions. Hence, short-term effect of formalin can be expected.