• Ecotoxicity assessment of environmental pollutants by earthworms.

• Genotoxicity assessment of environmental pollutants by plants and rodents

Soil is the main sink for all the chemicals. The pesticides, which are used to combat the menace of insect pests and weeds ultimately find their way to soil and disturb the population of non-target organisms. Since the earthworms are eco-friendly and belong to the trophic net work, they also get affected by various chemicals. Apart from this, they reflect the condition of the soil as well as nearby water bodies as they inhabit the moist soil. Being hermaphrodite they reflect the effect of pollutant on both male and female reproductive organs simultaneously. 

The use of Italian earthworm Eisenia foetida is very well approved by OECD for toxicity testing. Beside this, an Indian earthworm Metaphire posthuma is also established as a sensitive model by our group for the same. Acute toxicity studies showed that the Indian earthworm is more sensitive than Eisenia foetida. These earthworms are regularly being used for acute toxicity testing. 

Modern Agriculture involves indiscriminate use of synthetic chemicals. Pesticides are the major part that is used in agricultural areas and also for domestic pest control. In general, pesticides are the synthetic chemicals used to kill the pests that cause serious damage to agricultural crops and other organisms. Incorporation of plant and animal test systems has been well accepted and recognized for the genotoxicity assessment of these chemicals. Chromosomes are advocated to be reliable and sensitive bioindicator of genetic damage. Many plant systems such as Allium cepa (onion), Allium sativum (garlic), Vicia faba (broad bean) species have been standardized and validated for the evaluation of genotoxic, cytotoxic and phytotoxic potential of environmental chemicals. 

Reasons of recommendation to use the plant systems like Allium cepa, Allium sativum, Vicia faba, are:

a) Easy availability and maintenance in laboratory conditions at very low cost. 

b) Large and uniform size of chromosomes. 

c) Low chromosome no. 

d) Root tips provide high frequency of proliferating cells. 

e) Relatively less time and space for the experimental evaluation. 

Mus musculus is also a representative model of mammalian system and well approved by regulatory agencies. A large number of dividing cells can be obtained from bone marrow having 24 hr cell cycle and is conveniently used for experimental purposes.

• Ecotoxicity by earthworms

• Genotoxicity by plant and rodent models under the scope of NABL

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