The Pioche weekly record. [volume] (Pioche, Nev.) 1877-1900, 1894-05-24
NEVADA AGRICULTURAL EXPERT.
MENT STATION.
Is There Danger of Poisoning From
Eating Sprayed Fruit7
Newspaper Bulletin No. II. j

Newspaper Bulletin No. A.
This is question which has been asked
many times and undoubtedly the fear OF
possible harm has kept many from using
this valuable method Of combating insect
foes. To allay any such fears. and thus
perhaps prevent the disuse of insectcde
sprays in many cases where they are really
needed, this e"spaper bulletin is published.
The only sprays used a. insecticides which
are at all dangerous to use are the arsenic
compounds and the copper compounds
though these latter are much less poisonous
than the former Both Paris green and
London purple have been used extensively
for many years in this county as insecticides
and case Of fatal poisoning has yet to be
recorded. The great danger lies i'll having
the poison about the ranch in bulk. The
supposed danger has developed great deal
of opposition to the use OF Paris green, and
it has been but year OF 30 since the sale of
American apples in English markets rcceiv.
ed set back from this supposed danger of
arsenical poisoning from their consumption.
1t was shown in 1878 by McMurtrie, of
U. s. Department OF Agriculture, that the
most rigorous chemical analysis detects no
arsenic in the composition Of plants taken
from a soil 30 saturated with Paris green
that the plants wilted from its influence,
thus it can be safely assumed that plants
and vegetables can convey the poison to the
consumer only through the very small guam.
tity of arsenic which may be left from spray.
ing on the edible part of the plant 1t
would seem at first thought that the use of
Parsgreen on plant like the cabbage would
be very unsafe but the absence of danger
hes been shown by Professor Gillette, Of the
Colorado station AZ follows
Where the green is busted from bag
in the proportion OF one ouocs to one hun,
bred ounces Of flour, and just enough applied
on the leaves say for twenty eight heads
one ounce of the mixture, the worms will
all be killed in two or three days, while the
average amount OF poison on each head will
be about one.seventh of grain. Fully half
of the powder will fall on the outside leaves
and on the ground, aud thus person would
have to eat about twenty eight heads of
cabbage to consume q poisonous dose Of
arsenic, even il the balance OF the poison
remained after cooking"
In the case of spraying apple orchards
there is scarcely possibility of injury tc
the consumer, for where the poison is used
in the proportion OF one pound to two hun
bred gallons of water the arsenic will be SC
distributed that it will be impossible for q
sufficient quantity to collect upon any given
appleto have the slightest injurious effect
upon the consumer. In fact an individual
would have to eat several barrels of apples
at single meul to absorb fatal dose. Al
experiment showing the minute quantity Of
arsenic used to one tree in ordinary spray
ing was made by Professor A. j, Cook Of
Michigan. He placed thick paper under &
tree and thoroughly sprayed the tree on {
windy day SO that the dripping was excess
i've, After dripping ceased, the papel
covering seventytwo square feet wa,
analysed and four-tenths grains OF arsenic
found.
In regard to the copper solutions it may
be said that the amount Of copper found OF
grapes intelligently sprayed is rarely NOR,
than five mlligrams (0,0O5) per kilograu
(about two pounds) the average is p to
milligrams per kilogram. In other word
1000 900 pounds of grapes sprayed in thu
usual way with Bordeaux mixture would
contain p to D pounds of copper. Accord
ing to Gauthier Professor of chemistry o.
the Faculty of Medicine, Paris, an adult cal
absorb daily. for period of several week
without evil effects from two tenths to five
tenths grams Il gram l543S grains) o
copper sulphate (blue vtrol,) On this basi
an adult may eat from 300 20 500 pounds o
sprayed grapes per day without fear of evi
effects from the copper.
N. L. WILSON, Chemist.
Repo Nav Nav IL 1904