Table 1.
Evidence for an association between environmental estrogen exposures and the development of asthma
| Types of studies and topic and type of patients | Findings of study | Finding in asthma |
|---|---|---|
| Human epidemiology | Significant positive association between urinary BPA and lifetime prevalence of allergic asthma [54] | 10-fold increase in BPA was independently associated with higher likelyhood of allergic asthma in females |
| All patients with urinary BPA measurements in NHANES 2005–2006 survey | ||
| Human epidemiology | Significant positive association between mid-gestational urinary excretion of BPA and incidence of wheeze by age 6 months [55▪] | Wheezing in the first 6 months of life is positively associated with subsequent episodes of wheezing (asthma) |
| Pregnant women and their children followed up for 3 years | ||
| Human epidemiology | Male children have higher level of BPA in amniotic fluid than female children [56] | |
| Several relatively small group studies of urinary BPA | ||
| Human epidemiology | Urinary BPA is higher in children than in adults [57] | Age at diagnosis of asthma (80% by age 5 years) |
| NHANES | ||
| Human epidemiology | Urinary BPA is lowest in Mexican Hispanics and highest in African–Americans [2,58] | Ethnicity order for asthma prevalence same as order for urinary BPA |
| NHANES | ||
| Small-animal study | Perinatal exposure to BPA via dams’ drinking water [47] | Pups from BPA exposed were more likely to develop each manifestation of allergic asthma |
| Small-animal study | Prenatal vs. postnatal exposure to maternal BPA [52▪▪] | Prenatal exposure required to develop after postnatal allergen sensitization |
| Cell culture experiments on mouse and human mast cells to which endogenous and EEs were added | Both forms of estrogens induce partial release of mediators and augments release induced by IgE –allergen exposure [13,27] | About 40% of women have perimenstrual worsening of their asthma symptoms |
| Small-animal model | Urinary phthalate secretion relationship to allergy and asthma; the phthalate DEHP increases the IgE response to OVA [17,59▪,60▪] | Urinary phthalate level is associated with asthma prevalence |
The table gives a summary of growing body of evidence suggesting a relationship between environmental estrogens and the development of asthma. EEs, environmental estrogens; IgE, immunoglobulin E.