The prevalence of neurological and neurodevelopmental conditions has increased over the past decade, with experts suggesting that environmental factors could be contributing to this rise. A new study from Case Western Reserve University School of Medicine has found that some common environmental chemicals can damage specialized brain cells called oligodendrocytes, which are responsible for generating myelin sheaths on nerve cells. Exposure to these chemicals may explain the increase in conditions such as autism-spectrum disorders, attention deficit disorders, and multiple sclerosis.
The researchers assessed the impact of various chemicals on oligodendrocytes, organoid systems, and developing brains of mice, finding that organophosphate flame retardants and quaternary ammonium compounds (QACs) damaged oligodendrocytes without affecting other brain cells. Oligodendrocyte production starts during fetal development, with mature oligodendrocytes crucial for maintaining myelin sheaths that protect nerve cells. The study used oligodendrocyte progenitor cells (OPCs) derived from mouse pluripotent stem cells to assess the effects of 1,823 different chemicals on oligodendrocyte development.
Organophosphate flame retardants and QACs had adverse effects on oligodendrocytes, with the former inhibiting their development from OPCs and the latter causing cell death. In mouse experiments, quaternary ammonium compounds were found to cross the blood-brain barrier and accumulate in brain tissue, resulting in the loss of oligodendrocyte cells in various regions of the brain. Human cortical organoid models exposed to an organophosphate flame retardant showed a reduction in mature oligodendrocytes, suggesting a disruption in cell maturation.
Children with higher levels of the organophosphate metabolite bis (1,3-dichloro-2-propyl) phosphate (BDCIPP) in their urine were found to have increased risk of special educational needs or motor dysfunction. The study suggests a link between organophosphate flame retardant exposure and abnormal neurodevelopment. To reduce exposure to these chemicals, experts recommend using alternative disinfectants such as caprylic acid, citric acid, lactic acid, hydrogen peroxide, and alcohol. Pregnant women, children, and individuals with chronic diseases should be especially mindful of potential chemical exposure.
While the study provides valuable insights into how environmental chemicals can impact oligodendrocyte development and potentially contribute to neurodevelopmental conditions, caution is advised when interpreting the findings. Human beings are complex, and further epidemiological and fundamental studies are needed to establish a direct causal relationship between these chemicals and diseases like autism and multiple sclerosis. The study serves as a foundation for future research into the effects of environmental chemicals on brain cells and highlights the importance of reducing exposure to harmful substances to protect public health.