A baby’s exposure to air pollution while in the womb is associated with the development of certain mental health problems once the baby reaches adolescence, according to new research. The study led by the University of Bristol, published in Open JAMA Network today [28 May]examined the long-term mental health impact of early exposure to air and noise pollution.
There is growing evidence to suggest that air pollution, which includes toxic gases and particles, could contribute to mental health problems. It is thought that pollution could negatively affect mental health through numerous pathways, including by compromising the blood-brain barrier, promoting neuroinflammation and oxidative stress, and directly entering the brain and damaging tissues.
Although youth is a key period for the emergence of these problems, relatively few studies have so far investigated the associations of air and noise exposure during the first years of life with mental health.
In this new study, researchers sought to examine the long-term impact of exposure to air and noise pollution during pregnancy, early childhood, and adolescence on three common mental health problems: psychotic experiences (including hallucinations, such as hearing or seeing things that others cannot, and delusions, such as having very paranoid thoughts), depression and anxiety.
To investigate this, the team used data from more than 9,000 participants from the Bristol ’90s Kids Birth Cohort Study (also known as the Avon Longitudinal Study of Parents and Children), which recruited more than 14,000 pregnant women from the area. from Bristol between 1991 and 1992. and has followed the lives of the women, children and their partners ever since.
By linking participants’ early childhood data with their mental health reports at ages 13, 18 and 24, the researchers were able to use this to map outdoor air and noise pollution in south-west England at different times. moments.
The researchers found that relatively small increases in fine particles during pregnancy and childhood were associated with more psychotic experiences and symptoms of depression many years later, in adolescence and early adulthood. These associations persisted after accounting for many related risk factors, such as family psychiatric history, socioeconomic status, and other area-level factors such as population density, deprivation, green space, and social fragmentation.
The team found that every 0.72 micrograms per cubic meter increase in fine particulate matter (PM2.5) during pregnancy and childhood was associated with 11 percent greater odds and 9 percent greater odds of psychotic experiences, respectively; while exposure during pregnancy was associated with a 10 percent increase in the odds of depression. In contrast, greater exposure to noise pollution in childhood and adolescence was later associated with more anxiety symptoms.
Dr Joanne Newbury, Sir Henry Wellcome Postdoctoral Research Fellow at the University’s Bristol Medical School: Population Health Sciences (PHS) and lead author of the study, said: “Childhood, adolescence and adulthood Early life are critical periods for the development of psychiatric disorders: worldwide, almost two-thirds of those affected become ill by the age of 25. Our findings add to a growing body of evidence (from different populations, locations and using different. study designs) suggesting a detrimental impact of air pollution (and potentially noise pollution) on mental health.
“This is an important concern, because air pollution is now a very common exposure and rates of mental health problems are increasing globally. Since pollution is also a preventable exposure, interventions to reduce exposure, such as Low-emission zones could potentially improve mental health. Interventions targeting vulnerable groups, including pregnant women and children, could also provide an opportunity to more quickly reduce exposure.
“It is important to emphasize that these findings alone do not prove a causal association. However, other recent studies have shown that low-emission zones appear to have a positive impact on mental health.”
The research, which involved researchers from King’s College London, University College London and Cardiff University, was funded by the University of Bristol, Wellcome, the Economic and Social Research Council (ESRC), the Research Council (MRC) and the National Institute of Health and Care. Research (NIHR) and the Natural Environment Research Council (NERC).