Disadvantages of pesticides are:

i. Pesticides are detrimental to the environment and produce considerable damage to ecosystems.
ii. Insecticides and herbicides may be harmful for non-target species.
iii. Pesticides pollute air, water and soil.
iv. Carried by the wind, pesticide suspensions contaminate other areas.
v. Pesticides affect considerably natural biological equilibrium.
vi. Pesticides diminish biodiversity, reduce nitrogen fixation, contribute to the disappearance of pollinators, threaten fish, and destroy bird and animal habitats.
vii. Pets may also become affected by strong pesticides.
viii. Pesticide exposure is damaging to the immune system.
ix. Pesticides are poisonous and toxic to health.