A new study has linked dirt and air pollution to multiple neuropsychiatric conditions, as well as an increased risk of developing personality disorders. The link was first identified using environmental data from the US, but was profound enough that researchers double-checked their work by looking for similar links using data from Denmark. The association remained for the second country, as well.
The research comes from the University of Chicago Medicine, where a team of scientists first analyzed air pollution in the US using data from the EPA. The information was broken down to individual counties; places with the worst air quality were found to have 6-percent higher instances of major depression and 27-percent higher instances of bipolar disorder.
In addition to these two conditions and their correlation with air pollution, the study also found what is called a ‘strong link’ between pollution in the soil and an increase in personality disorders. According to the researchers, these results ‘seemed unusually strong,’ so they sought to validate them by using the same method on environmental data from Denmark.
Unlike in the United States, Denmark keeps track of pollution data on smaller regions. The results, it turns out, were largely the same: counties in Denmark with the worst air pollution had a 29-percent increase in bipolar disorder. More concerning, however, were stronger links with other serious conditions.
The study found, for example, that exposure to poor air quality in early childhood was linked to a 148-percent increase in schizophrenia, a 50-percent increase in major depression, and a 162-percent increase in personality disorders. It’s unclear how air and soil pollution may trigger the onset of these diseases, assuming it actually is a cause of onset in some people.
The full study can be read here.