Morpho-histological and enzymatic alterations in earthworms Drawida willsi and Lampito mauritii exposed to urea, phosphogypsum and paper mill sludge

ABSTRACT

The effects of varying concentrations of urea, phosphogypsum and paper mill sludge (PMS) on the morphology, histology, tissue protein content, lipid peroxidation (LPX), activities of lactate dehydrogenase (LDH), acetylcholinesterase (AChE) and catalase in earthworms Drawida willsi and Lampito mauritii have been studied over an exposure period of 24 hr. Integumentary lesions, clitellar swelling and loss of pigmentations were found to be major morpho-pathological changes in the worms. Histology indicated cuticular damage, ruptured epithelium and muscle fibres with accumulation of cellular debris. Lowest tissue protein content (57.02 ± 4.02 mg/g tissue) and highest LPX (0.113 ± 0.04, 0.137 ± 0.08 nmol/mg protein) were noticed in D. willsi at a high concentration of PMS, whereas highest tissue protein content was observed in L. mauritii (115.32 ± 7.18 mg/g tissue) with the same treatment. In both the species, LDH activity was minimum at a high concentration of urea (0.172 ± 0.02; 0.247 ± 0.08 U/mg protein). AChE activity was highest (0.099 ± 0.002 U/mg protein) at a high concentration of PMS in D. willsi, whereas catalase activity was the maximum (0.338 ± 0.02 U/mg protein) at high concentrations of PMS in L. mauritii. The study indicated that morpho-histological and enzymatic alterations in these earthworms exposed to agrochemicals could be useful biomarkers to evaluate soil toxicity.

KEYWORDS:

• Biomarker
• earthworm
• paper mill sludge
• phosphogypsum
• urea

Acknowledgement

The authors are thankful to the Science and Technology Department, Government of Odisha, India for financial support.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Suryasikha Samal is a Research Scholar.

Sunanda Sahoo is a Lecturer in Life Science.

C. S. K. Mishra is a Professor of Zoology.

ORCID

Suryasikha Samal http://orcid.org/0000-0001-7301-3249

Sunanda Sahoo http://orcid.org/0000-0002-1934-8133

C. S. K. Mishra http://orcid.org/0000-0003-1105-9764