Escalating prevalence of autism spectrum disorders (ASD) in recent decades has triggered increasing efforts in understanding roles played by environmental risk factors as a way to address this widespread public health concern. Several epidemiological studies show associations between developmental exposure to traffic-related air pollution and increased ASD risk. In rodent models, a limited number of studies have shown that developmental exposure to ambient ultrafine particulates or diesel exhaust (DE) can result in behavioural phenotypes consistent with mild ASD. The authors performed a series of experiments to determine whether developmental DE exposure induces ASD-related behaviours in mice. C57Bl/6J mice were exposed from embryonic day 0 to postnatal day 21 to 250-300 ?g/m3 DE or filtered air (FA) as control. Mice exposed developmentally to DE exhibited deficits in all three of the hallmark categories of ASD behaviour: reduced social interaction in the reciprocal interaction and social preference tests, increased repetitive behaviour in the T-maze and marble-burying test, and reduced or altered communication as assessed by measuring isolation-induced ultrasonic vocalisations and responses to social odours. These findings demonstrate that exposure to traffic-related air pollution, in particular that associated with diesel-fuel combustion, can cause ASD-related behavioural changes in mice, and raise concern about air pollution as a contributor to the onset of ASD in humans.
Authors: Chang YC, Cole TB, Costa LG. ; Full Source: Particle and Fibre Toxicology. 2018 Apr 20;15(1):18. doi: 10.1186/s12989-018-0254-4.