Don, adding baking soda to pickle does two things. It causes the
release of carbon dioxide gas. Same stuff we exhale with every
breath, and in these quantities, not toxic. Plants need it…
It also causes a bunch of foaming and bubbling to take place, as the
gas is evolved. that can be relatively rapid, and herein is the
danger, since it’s not hard to get a pickle pot to overflow with all
that foam. Plus, bursting foam bubbles can cause an aerosol of tiny
bits of the liquid itself to be projected up into the air, where it
will, of course, slowly settle out, or evaporate leaving dried
particulate matter. the amounts of this aerosol can be assumed to be
quite small. Dangers thereof are most likely minimal, especially
since the main dissolved metal you’ll find in the pickle will be
copper, and if you’re careless with your pickle, iron. Not heavier
metals, usually, than that, since then we’d be talking about silver or
gold, and neither forms soluable sulphates in the pickle. You might,
I guess, also get lead or cadmium compounds, if you’re pickling
metals with that in them, though I’m not a chemist, so I’m not sure
of that. In any case, frankly, I’d not consider the aerosol
potential as dangerous. But the spillage from overflowing foam
certainly could make a mess of the floor, and if the pickle is hot,
cause nasty burns if it’s spilling on you.
Overall, my feeling is that the main dangers of our pickle is the
acid fumes released by the normal hot working liquid (and of course
hot spills which can burn, as well as destroying clothing). It’s not
all that much, but in poorly ventilated areas, it certainly can cause
lung irritation, especially with chronic exposure, as we get when
this is our job day to day. Cold pickle doesn’t do that of course,
but it also doesn’t work as well. So if your ventilation is
questionable, simply keep a cover on your pickle pot. Keeps the
fumes under control nicely. If you can smell the stuff when you go
near it, address the problem. If you can’t, you probably don’t have
a problem.
As to disposal, there’s nothing created, chemically, that worse than
the pickle itself, but as has been pointed out, dissolved metal
(copper) is not destroyed. The main purpose of neutralizing the acid
would be to neutralize the corrosive potential of that acid, and in
many cases, this is not needed. If you’re dumping it down a septic
system (I’d probably not recommend that), then you’ll most likely
want to neutralize the acid. If you’re connected to a normal
municipal waste system, then I doubt it’s needed, since the
considerable dilution it would quickly get pretty much solves the
problem. Sodium bisulphate in trace amounts in the water does little
if any harm, and is quickly neutralized in the environment by
reacting with calcium carbonate (limestone). The copper, well that
depends on how much. If you’re an industrial user of pickle, you’ve
got a toxic material to deal with. If you’re a small jeweler, who
once a month has a couple cups of used pickle, which might contain a
few milligrams of copper sulphate, if that, then frankly, these tiny
amounts of copper aren’t significant to anything. Now, in a global
scale of things, all the pickle generated by all the jewelers in an
area might indeed be significant amounts of copper… but that’s
another issue. Remember that the main environmental effect of copper
is that algae doesn’t like it, and if there’s enough, some
invertebrate organisms also don’t like it. It’s main effect on fish
is to make them healthier, since if theres enough, it kills some of
the parasites. copper compounds are widely used as remedies for
various infections, especially fungal and parasitic, in aquarium
fish. when I do that, eventually I’ll have to do a water change (to
get rid of the color, mostly) and in doing that, I’ll be dumping more
copper into the waste water than my pickle pot ever does.
If it helps, I did contact my municipal hazardous waste department
once, to ask about this, after getting curious from another orchid
thread along this line. After getting past the various trained
monkeys who respond by rote, and finally reaching someone who
actually knew the subject, i was told pretty much what I just said
above. Dump the used pickle down the toilet and flush. Won’t cause
harm in non-industrial quantities.
Regarding pickle brands, I’m pretty fed up with Sparex. Not that it
doesn’t work. It works just fine. But apparently, the stuff they’re
packaging isn’t real pure. On mixing, it reacts in some manner to
generate a sort of waxy/greasy brownish scum. Not sure if this is a
reaction to stuff in the water, but I suspect it’s not. My feeling
is that it’s just impurities in the chemical which are very finely
divided, and which aren’t immediately visible other than by the
yellowish color of the mixed liquid. With time, the tiny suspended
particles combine and float, forming the visible scum. Messy and
nasty. And not, apparently, due to the sodium bisulphate itself,
since using lab grade chemical mixes to a colorless clear solution
with no scum. I’ve stopped using sparex. Now I use the version of
sodium bisulphate sold for lowering the ph in your hot tub (if you’re
lucky enough to have one. Can I come over?) Sold in the local
hardware stores, it ends up being cheaper than Sparex. And it’s
apparently pure enough to not cause that damn scum formation. If
the folks at Krohn technical products (the name on the Sparex can)
are reading this, take note. Your sparex product is junky
contaminated material sold for a too-high price. pay attention. It
might make me think twice about going to your product line for your
main items, such as your sometimes costly plating solutions…
Peter Rowe