Conclusion

Our findings suggest that higher ambient air pollution exposure is associated with greater risk of NAE and AE in adult men and an increased risk of aeroallergen sensitisation in both sexes. Ongoing efforts to reduce ambient air pollution exposure are likely to have a range of health benefits. Nevertheless, further research is needed to identify the components of ambient air pollution that exert the major effects, the extent of exposure required to increase risk of eczema and the factors that determine individual susceptibility. Further efforts are required to harmonize measurement of ambient air pollution markers, case definitions, study designs, and assessment of confounding factors to aid in replication of findings in this area.