On looking at the prices of masks and filters, I figured that it could eventually get rather expensive for me. Moreover, there's an article in a newspaper that these masks don't really help:
Don't be fooled by safety masks (Sep 30, 2001)
According to a two-year painstaking study conducted by a group of researchers in the department of chemical engineering, Indian Institute of Science, no mask being sold in Bangalore is effective against the most common and harmful pollutants: carbon monoxide (co), sulphur dioxide (so2), suspended particulate matter (spm), oxides of nitrogen (nox). The study, commissioned by the council for scientific and industrial research (csir), has been examining all the material used in the filters inside the plastic masks. To their utter dismay, researchers found that people using these masks are being fooled beyond imagination. says senior scientific officer Mr.J.R. Mudakavi: "we have tested more than a dozen such masks available in the city's markets. I am sorry to see that none of them informs the buyer what it is effective against, what load it can take, if the filter is recyclable, et al". The most injurious of all, CO, is not filtered by any mask. sulphur dioxide is absorbed by some filters to some extent, but given its concentration in the atmosphere, these masks are effective only for 2-3 hours. no user is told that if the filter is washed it can be used efficaciously a few more times. one of the dreaded pollutants is spm (small particles from industry, stone crushing, construction materials, exhaust, etc) which when inhaled in large quantity gets deposited in the lungs and can cause silicosis.
Ok, so if even the anti-pollution masks can't filter out CO or SO2 properly, then that leaves the danger of the particulate matter which in my opinion, could be prevented with just a cloth wrapped around the nose and mouth.
Not a thin layer of cloth. A cloth where the folds form a couple of layers over your face and nose. If this cloth is moistened a bit, shouldn't it be effective against particulate matter.
For a short ride of maybe 30 minutes, won't a simple cloth be more cost effective and offer a reasonable amount of protection against pollutants?