The question about pollution-free pollen is an interesting one!  Oviously
you do not want to take pollen (or honey for that matter) from hives located
downwind from highways, power plants, chemical or other factories.  So I
would think the best pollen/honey for consumption would be that taken from
rural areas (try Arizona, Canadian provinces, northern California, OR, WA,
S. America, etc).  Several good refs follow:
Molzahn, D. et al.  1989.  Transfer of radioactive cesium from soil to rape
plants, rape blossoms, and rape honey.  Apidologie 20:473.
Bromenshenk, J.J. et al.  1985.  Pollution monitoring of Puget Sound
with Honey bees.  Science 227:632.
Free, J.B. et al.  1983. Using foraging honeybees to sample an area
for trace metals.  Environ. Internat. 9:9.
Hill, D.W. et al.  1981.  Metals in honey produced and marketed in
Connecticut.  Univ. Conn. Agr. Exp. Sta Res Rpt 68:1-8.
 
cheers, e.e. southwick
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