[Arid_gardener] Jennie -- Arsenic in water source

[Genie]

Dear Jennie,

While you are rightfully concerned about the toxicology of arsenic (As) 
in the water for fruit trees (and perhaps
other crops you may wish to grow) let me give you a bit of reassuring 
information:  Arsenic is so widely distributed,
that human exposure is almost inevitable.   Measurable quantities 
(measured in µg/litre)  are found in rainwater as well
as drinking water!  Arsenic is found in ALL types of food, but 
concentrations vary depending upon the food type,
type of soil, water, geochemical activity, and use of arsenic pesticides.
 
To address your central question; "effects of arsenic externally" - the 
answer which comes quickly to mind is... hair.
High levels of arsenic will cause hair to break!  In fact, hair and 
nails (fingernails and toenails) can be tested with
reasonable accuracy for presence and levels.   Arsenic is rapidly 
metabolized/excreted into urine and the sum of arsenic
metabolites in urine are used as biomarkers of *recent* arsenic exposure.

Research data is limited, however it is generally accepted that the 
highest concentrations of total arsenic is found in
seafood.   Livestock and grains have higher concentrations than 
vegetables, fruit, and dairy products. 
Although contamination from industry, mining, agriculture, etc., cannot 
be denied... did you know that AT LEAST 35%
of the contamination occurs naturally?  Arsenic is the primary 
constituent of more than 200 mineral species.
Volcanic activity (past or present) literally overwhelms soils with 
arsenic, that would otherwise contain an acceptable level.
And, an active volcano that "blows its top" spews pollutants (not simply 
arsenic) so far up in the atmosphere, that the
effects last for more than a decade.   Civilized society has abandoned 
the practice of "sacrificing a virgin female"
into a live volcano  :-)   upon discovering there's really nothing we 
can do to completely eradicate all evils from our water,
soil, air, crops, rainwater, etc..

I sincerely hope this gave you *some* comfort (and perhaps a giggle) 
Jennie. 
If you have information that your water source has exceedingly high 
concentrations of arsenic, determine whether the
contamination is from an organic or inorganic source and the 
concentration (µg/litre).  If you are watering only a few fruit
trees, consider purchasing an inexpensive filter made to work inline 
with a garden hose.  A quick search via "google"
turned up this EPA data: 

"Published by Borum & Abernathy (1994). Concentrations of arsenic were 
in the range of < 2.5-28 µg/litre for surface waters and < 5-48
µg/litre for groundwater sources."

Moreover, nearly 70% of the nearly 4,000 samples analyzed contained 
arsenic, nationwide.
Aside from grasses, mustard, and some types of lettuce... I was unable 
to find anything definitive regarding adverse
effects to fruit and/or fruit trees.   Dick Gross (a fruit expert and 
member of our Group)  will likely have more info
about arsenic uptake in fruit trees.

If I failed to make you feel a little bit better, Jennie, consider that 
arsenic has been used to treat a broad range of ailments
including: cancer, heart problems, parasites, syphilis... and the 
heartbreak of psoriasis!   :-D 

Kindest Regards,   Genie -- in Tucson



 

        
 

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