The Costs of Green Space

Preliminary research suggests green space carries costs alongside its benefits. Allergenic pollen is the best-documented: people living near green space with higher allergenic pollen, whether measured or merely perceived, report worse mental health. Reviews also note injury, vector-borne disease and drowning risk near water, and greening can raise housing costs and displace the residents it was meant to serve. We grade this C because the environmental evidence carries only a small number of clean sources on these costs against a very large literature on the benefits, so the asymmetry here reflects the asymmetry in the evidence rather than a settled balance.