One analysis of eight Dutch cohorts found a significant pooled prevalence of depression [odds ratio (OR) = 1.07] per 0.2 × 10−5 increase in PM2.5 absorbance

Two other meta-analyses also reported small but significant associations at the shorter (<6 months) and longer terms (>6 months) (ORs = 1.10 and 1.06).

One meta-analysis reported a significant association between depression and PM10 at the very short term (<2 weeks) (OR = 1.03).

Other pollutants were found to be significantly associated with depression: nitrogen dioxide (NO2; OR = 1.04), carbon monoxide (CO; OR = 1.01); and sulfur dioxide (SO2; OR = 1.03).

A significant association was also found between noise from aircrafts and depression (OR = 1.14).

Several meta-analyses found significant associations between pollutants and ASD when the mothers were exposed during pregnancy: PM2.5 (ORs ranging from 1.06 to 2.32), PM10 (OR = 1.07), ozone (O3; OR = 1.03 and RR = 1.05), NO2 (OR = 1.02), and solvents (OR = 1.03).

One study found a lower risk for ASD and pesticides (OR = 0.83).

Other meta-analyses found a significant association between PM10 and suicide (RR = 1.02) and between NO2 and suicide (RR = 1.03).