Tobacco Control 2000; 9:98Banning outdoor smoking is scientifically justifiable The reality of atmospheric dispersion of ETS
in outdoor settings is this: individual cigarettes are point sources
of air pollution and, therefore, smoking in groups becomes an
area source. Outdoor air pollutants from individual point sources
are subject to plume rise if the temperature of the smoke plume
is hotter that the surrounding air. However, if the plume has
a small cross-section, as far a cigarette, it will rapidly cool
and lose its upward momentum, and then will subside as the combustions
particles and gases are heavier than air. Thus, in the case of
no wind, the cigarette plume will rise to a certain height and
then descend. In a case where a group of smokers are sitting in
an outdoor café, on a hospital patio, or in stadium seats,
their smoke will tend to saturate the local area with ETS. Where there is wind, the amount of thermally
induced plume rise will be inversely proportional to the wind
velocity--doubling the wind velocity will halve the plume rise.
In this case, the cigarette plume will resemble a cone tilted
at an angle to the vertical. The width of the cone and its angle
with the ground will depend upon the wind velocity: a higher wind
will create a more horizontal cone, a smaller cone angle, and
a higher concentration of ETS for downwind non-smokers. If there
are multiple cigarette sources, the downwind concentrations will
consist of multiple intersections cones--that is, overlapping
plumes. As the wind direction changes, ETS pollution will be spread
in various directions, fumigating downwind non-smokers. ETS contains
a large quantity of respirable particles, which can cause breathing
difficulties for those with chronic respiratory diseases, or trigger
an asthmatic attack in those with disabling asthma. For the remainder
of non-smokers, ETS causes eye, nose, and throat irritation, just
like any other noxious outdoor fumes, such as bus exhaust. If
smoking is freely permitted in these venues, hospital orderlies,
sports spectators, outdoor café aficionados, and beach
goers might have to be restricted to the ranks of the non-asthmatic. Have you ever had dinner in an outdoor café
in Pairs, Athens, Las Palmas, or Salt Lake spoiled by smokers
at adjacent tables? Have you ever had to move your blanket on
a public beach because someone suddenly started smoking upwind,
replacing clean salt air with irritating smoke? Smoking has no
social value other than to create unnecessary work for physicians,
and windfall profits for morticians. Even if outdoor environmental
tobacco smoke were no more hazardous than dog excrement stuck
to the bottom of a shoe, in many places laws require dog owners
to avoid fouling public areas. Is this too much to ask of smokers? JAMES REPACE RepaceAssociation, Inc, |
