Effect of heavy metals on the survival, growth and development of earthworm Eisenia fetida

Abstract

The present laboratory study was carried out to determine the effect of the metal contaminated soil on the survival, growth and development of Eisenia fetida. Metal contaminated soil samples were collected from five different sites of Ludhiana city which is an industrial hub of Punjab. Maximum heavy metal concentrations were recorded in soil sample taken from hambran around the Buddha Nullah and minimum concentration of heavy metal from haibowal. The level of heavy metals chromium and nickel (347 ppm and 189 ppm) were higher than permissible limits according to CCME (2001), whereas lead (42.6 ppm) was within permissible limits. Adult E. fetida were exposed to different concentrations of heavy metals in artificial soil for 28 days. Significant effects were observed on growth and reproduction of the tested organisms. There was 100% survival of E. fetida in soil amended with lead, chromium and nickel along with morphological abnormalities such as extrusion of coelomic fluid. It was observed that the worms in the low and high doses of heavy metal treated substrate produced cocoons with a one week and two week delay, respectively, vis-a-vis the control group. Furthermore, the emergence of hatchlings started one week earlier in control than in soil treated with medium and high concentration of metals. It is safely concluded that presence of heavy metal in soils adversely affects the growth, reproduction and development of E. fetida. Results ofthe study indicated that reproduction was more sensitive to higher concentrations of heavy metal contaminated soil than survival or weight change.

Negative Effect of Phosphogypsum Over Physiological Activity of Earthworm Eisenia Fetida

“…In a such kind of study, Honsi et al (2003) reported no effect of heavy metals (Cu, Zn, Cd and Pb) on survival of earthworm E. fetida exposed to contaminated soils in Norway despite the fact that the concentrations of metals were high (max Pb -8750 μg gˉ¹, Cd -110 μg gˉ¹ soil). Kaur and Hundal (2016) 2009) findings also support our results. Spurgeon and Hopkin (1996) also argued that the worms living in metal polluted soils reached the lower weight or needed more time to reach the maximum weight than in non-polluted sites.…”

Eco-toxic effects of lead and nickel on survivability, reproduction and growth of earthworm (Eudrilus eugeniae)

“…These tests give a more ecologically pertinent sub-lethal endpoint than lethality. In eco-toxicological estimations reproduction is of pivotal importance because it influences population dynamics (Kaur and Hundal, 2016) [9] . Hence, the present study is set out to explore the effects of lead and nickel on survivability, growth and reproduction of E. eugeniae.…”

“…Shefali et al (2018) [17] reported the significant difference in body weight of worms treated with arsenic and chromium after the 28 th day of treatment as compared to control. The weight of worms was significantly affected by high levels of heavy metals in the study of Kaur and Hundal (2016) [9] . Reduction in body length of earthworms due to Pb and Ni exposure has also been reported by Urmila et al (2019) [20] .…”

“…If the earthworms in any ecosystem are in danger then the development of that particular ecosystem is very difficult (Dutta and Dutta, 2016) [6] . Nowadays soil pollution from heavy metal contamination has become a serious concern as it causes ground water contamination and biomagnification of heavy metals through food webs and therefore, considered as a major environmental issue (Loureiro et al, 2005; Kaur and Hundal, 2016) [12,9] . Earthworms act as an important link in the food webs by transferring energy from dead and decaying organic matter to higher trophic levels by acting as a prey for birds and terrestrial vertebrates (Parihar et al, 2019) [13] .…”

“…They are exposed to heavy metals through their skin and digestive system. Elevated concentration of heavy metals in soil can result in several destructive effects on earthworms such as reduced density, viability, cocoon production, growth and sexual development (Kaur and Hundal, 2016) [9] and thus indirectly affect the soil properties (Wang et al, 2018) [22] . Earthworms have therefore been used as biomarkers to spot contaminated soils and are used as a modal organism for terrestrial ecotoxicology studies (Tang et al, 2016) [18] .…”