The NPIC specialist explained why infants can be more sensitive to pesticides than adults. During pregnancy and infancy, the babies' brain, nervous system and organs are developing rapidly. The barrier that protects the brain, and the liver and kidneys which help remove harmful substances from the body, are immature in infants. Therefore, their bodies don't tolerate pesticide exposure as well as adults. Infants may also take in higher levels of pesticides than adults because they take more breaths per minute and have more skin relative to their body weight.

Specific behaviors may also put infants and young children at a greater risk of pesticide exposure compared to adults. Babies and young children are often closer to the ground where pesticides may have been applied, which increases their potential to breathe in certain chemicals. Babies that crawl on treated carpeting may have a greater potential to dislodge pesticide residue onto skin. Young children are also more likely to put their fingers, toys, and other objects into their mouths.

The NPIC specialist said that the EPA considers the potential for children to be more sensitive to pesticides when assessing a chemical's risk. Mark and Jamie learned that if they choose to use a pesticide, they need to read the pesticide labels first. The product must be approved for their intended use and applied according to label directions. The NPIC specialist also discussed steps they could take to minimize their exposure to pesticides, including moving the baby's things out of the way before spraying, and making sure that Jamie is out of the area while the product is being applied. Jamie and Mark could reduce their exposure even more by remaining out of the treated area until the pesticide is completely dry and the area is well ventilated. They also discussed allowing Mark or their veterinarian to apply the spot-on flea product to the dog, and ensuring that the application site is completely dry before petting the dog. Finally, the NPIC specialist directed Mark and Jamie to additional resources for integrated pest management (IPM) approaches to flea control.