General News · 2nd May 2016
Dietrich Schwarz (MD)
The return of warm sunny spring days following a long wet winter are welcome almost everywhere, but not on our unpaved roads. As the sun bakes the gravel, compacted fine dust particles loosen and are tossed dozens of feet into the air by passing cars. As more or less dense dust clouds they are ugly, uncomfortable and a deterrent for the tourist industry. And, as components of the road itself go up, so do annual road repair costs.
The dust clouds also present hazards both immediately, by reducing visibility, and with growing severity over time. Dust acts as an abrasive in engines and virtually all other mechanical equipment. On chronic exposure the dust clouds also are a serious health hazard. As we are forced to breathe dust with the air, tiny silicate particles become stuck in the lymphatic system of our lungs where they accumulate permanently in granulomas similar to those of tuberculosis. With the dust we also inhale microorganisms that can cause bronchitis and pneumonia. In combination and over time the result may be life-shortening emphysema. Naturally, problems are greatest for people living in homes close to these roads.
All this is preventable by simply reducing the dust. The best prevention would be, of course, to pave the roads. As this possibility seems to be constrained by budget limitations alternatives need to be considered. Dozens of years ago road crews used industrial organic chemical by-products of various sorts sprayed over dirt roads to control the dust. While this worked it also enraged the environmentally educated public, since the sprays were, unsurprisingly, considered toxic. An unfortunate result of this history is that up to the present day many people are fundamentally opposed to any kind of road spraying.
Consider, however, a substance used widely in BC to control road dust today: a magnesium (Mg) salt solution works similar to cement, binding dust particles. Mg in this solution is not toxic; on the contrary, it occurs in vast quantities in the oceans, where it seems essential to all life forms. As central atom in chlorophyll, Mg is critical for the generation of the oxygen we breathe and the removal of CO2 by our forests. In salads and vegetables we (should) eat it every day and it has many important functions in our bodies, e.g. in the control of submicroscopic pores in cell membranes and as enzyme components. To stay healthy we need Mg. When spraying our dusty roads, the Mg escaping may be more desirable than problematic for the environment.
Mg salt solution spraying should be considered a rational routine gravel road maintenance procedure as long as we cannot afford paving. Our Regional Director has committed herself to road dust control in her election campaign. Action due now may be budget dependent. If needed, priorities might be guided by the degree of sun exposure since the dust problem tends to be less severe on shadier roads. The dust clouds over our dry summer roads are a problem that can and should be solved.