>> I don't even use selenium toner on
>> a regular basis, since that's a
>> pollutant unless you live near the ocean.
>
> Care to expand upon that Mike? What's one's proximity to the
> ocean got to do with selenium toner being a pollutant?
Shel,
Because selenium is a pollutant in fresh water but not in seawater. If you
live in an area where your "gray water" (municipal term for used household
water that doesn't need to go to the septic tank or sewer) sheds to the
ocean, you can put selenium toner down the drain without a care--selenium
occurs naturally in seawater anyway and a miniscule bit more won't hurt
anything. However, if you live in an arid region where gray water is
processed and recovered or goes into the soil and thence to the water table,
it's not really a nice thing to do to add selenium to it.
Most selenium poisoning of water, however, is not the result of the
inconsequential amounts used by art photographers--it's the result of
irrigation in dry areas. By pumping water up from wells, watering crops with
it and then letting it settle down into the water table again, selenium is
"leached" out of the soil and into the water, and the concentrations of
selenium can get unacceptable. This is just a byproduct of filtering the
water through the soil again and again, not the result of Mad Scientist
Zoner photographers maniacally tossing spent toner down their household
drains. Still, it's not something I want to do, just for form's sake. There
are a number of papers that look just fine without toning and aren't much
improved with toning--my standard paper, Agfa MCC, being one of them--so I
just use those.
--Mike
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