Explain how harmful chemicals enter our bodies.
Chemical substances such as pesticides are sprayed over crop plants to protect them from pests and diseases. When herbivorous animals eat plant food, these poisonous chemical pesticides go into their bodies. Man, being an omnivore, eats plant food as well as the flesh of herbivores. Thus, the pesticides present in plant food and in the bodies of herbivores are transferred to the bodies of humans through food. In this way, harmful chemicals enter our bodies.