It is those who used the product indoors who are considered to have been at risk. The results of the HRA were hampered by the lack of quantitative data on the amount of pesticides used during the Gulf War, and the levels of pesticides present in the air and on surfaces to which US troops were exposed. The investigation also lacked information from veterans' hospital and medical records. The HRA does not account completely for some potentially important combined exposures. While it accounts to some extent for combinations of organophosphate and carbamate pesticides, it does not fully account for additional concurrent exposures to DEET, permethrin, pyridostigmine bromide, and nerve agents.
Some individuals are more susceptible to the effects of pesticides than others.
This may be due to several factors, including genetic make-up. For example, some individuals may be more efficient at detoxifying and clearing pesticides than others.