Common environmental toxins such as nicotine and metals have been linked to depressive symptoms such as feeling hopeless or having little interest in daily activities, according to a study of American adults.
Researchers found that inflammation triggered by these environmental toxins could be one of the possible underlying reasons.
The team of researchers, which included researchers from Peking University in China, analyzed toxin levels in blood and urine samples from more than 3,400 adults. The data was obtained from the National Health and Nutrition Examination Survey (NHANES), which tracks the health and nutrition of Americans.
Depression in participants was assessed using the Patient Health Questionnaire-9 (PHQ-9), which can establish the diagnosis, along with symptom severity.
Researchers found that toxins including heavy metals, nicotine and volatile organic compounds (VOCs) found in paints and varnishes increased the risk of depressive symptoms in participants.
The authors found that those with detectable levels of MHBMA2, a VOC, had a 74 percent higher risk of experiencing depression-like symptoms compared to those with undetectable levels.
Furthermore, men were found to be more vulnerable to the depressive effects of environmental toxins, compared to women.
The authors found that inflammation, measured by white blood cell counts, was one of the processes driving these links between toxins and depression-like symptoms.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)