I thought I'd share this article. It doesn't mention MS specifically, but apparently air pollution is linked with nervous system problems, including blood brain barrier dysfunction.
I'm not really interested in debating causes. I am interested in finding things that make this disease worse and how to avoid them or repair damage. Here's the citation and abstract. It's full text available and it's fairly easy to skim with clear subject headings. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3317189/
The Adverse Effects of Air Pollution on the Nervous System
Sermin Genc, Zeynep Zadeoglulari, [...], and Kursad Genc
Additional article information
Exposure to ambient air pollution is a serious and common public health concern
associated with growing morbidity and mortality worldwide. In the last decades,
the adverse effects of air pollution on the pulmonary and cardiovascular systems
have been well established in a series of major epidemiological and observational
studies. In the recent past, air pollution has also been associated with diseases
of the central nervous system (CNS), including stroke, Alzheimer's disease,
Parkinson's disease, and neurodevelopmental disorders. It has been demonstrated
that various components of air pollution, such as nanosized particles,
can easily translocate to the CNS where they can activate innate immune responses.
Furthermore, systemic inflammation arising from the pulmonary or cardiovascular system
can affect CNS health. Despite intense studies on the health effects of
ambient air pollution, the underlying molecular mechanisms of susceptibility
and disease remain largely elusive. However, emerging evidence suggests that
air pollution-induced neuroinflammation, oxidative stress, microglial activation,
cerebrovascular dysfunction, and alterations in the blood-brain barrier
contribute to CNS pathology. A better understanding of the mediators and mechanisms
will enable the development of new strategies to protect individuals at risk
and to reduce detrimental effects of air pollution on the nervous system and mental health.