IGHE and allergic asthma: In addition, it has been proven that as the concentration of heavy metals in the blood increases due to exposure to heavy metals, the concentration of IgE in the blood increases, which increases the severity of asthma, bronchial hypersensitivity, and the risk of allergic asthma by constricting smooth muscles (Wang et al., 2017; Wu et al., 2019; Zahedi et al., 2021).