Living near water-pollution sources associated with rare brain disorder

People who reside near industrial facilities that release water pollutants may have an increased risk of developing a rare brain disorder known as progressive supranuclear palsy (PSP), according to a study published in the medical journal Neurology. PSP is a type of atypical parkinsonism, a group of neurodegenerative diseases that can progress rapidly and respond differently to treatment compared to Parkinson's disease.

The study does not establish causation but suggests a potential association between environmental water pollutants and the onset of PSP. Study author Dr. Charlie Weige Zhao from Harvard Medical School stated that further research is required to confirm these findings.

The research involved analyzing health records of over 500,000 individuals in the United Kingdom over a period of up to 25 years. Out of these participants, 221 individuals were diagnosed with PSP. Researchers matched the PSP patients with 10 non-PSP individuals based on age and sex. Home addresses from 2007 were used to determine the proximity of participants to industrial facilities that emitted various pollutants.

The analysis revealed that about one-third of PSP patients lived within three miles (4.8 kilometers) of such facilities, while approximately one-quarter of non-PSP individuals resided in similar proximity.

The study found that residing near facilities emitting pesticides like atrazine, simazine, and diuron raised the risk of PSP by 66%. Exposure to inorganic pollutants, including phosphorus, nitrogen, and fluorides, increased PSP risk by 60%. Organic pollutants, such as benzene, ethylbenzene, and toluene, raised the risk by 52%, while heavy metals like lead, mercury, and cadmium raised the risk by 38%.

However, the study did not find a significant association between chlorinated solvents and persistent organic pollutants and PSP development.

Interestingly, the researchers also discovered that the proximity to the facility seemed to influence the risk. People living closer to the sources of pollution, up to a distance of approximately six miles (9.7 kilometers), had a higher chance of developing PSP. The study also noted that the duration of exposure to the pollutants played a role in the risk. Furthermore, the researchers highlighted that the overall risk of developing PSP remains low, regardless of where a person lives.

Some limitations of the study include the lack of comprehensive information on participants' job histories, which prevented a thorough analysis of occupational exposure to pollutants. Additionally, many industrial facilities emitted multiple types of pollutants, making it challenging to isolate the effects of any single pollutant.

Despite these limitations, the study provides valuable insight into the potential role of environmental water pollutants in the development of PSP, emphasizing the need for further research to confirm these findings.