8 BULLETIN 1027, U. S. DEPARTMENT OF AGEICULTUEE. 



In 1893 Davis (30) reported the determinations of arsenic on 

 celery that had been sprayed with Paris green at the rate of 1 pound 

 to 175 gallons of water. The results, obtained on the celery washed 

 without separating the stalks and prepared as for market, were as 

 follows: Sprayed once, 0.0244 grain of arsenious oxid per pound of 

 celery; sprayed twice, 0.0368 grain of arsenious oxid per pound of 

 celery. 



In 1893 Beach reported (12) the presence of from 0.00042 to 0.001 

 per cent of copper in celery that had been sprayed with Bordeaux 

 or ammoniacal copper carbonate solution, and 0.00081 per cent in 

 unsprayed celery, concluding that ''these investigations show that 

 when this sprayed celery was stripped and ready for market the 

 sprayed plants were no more poisonous than the unsprayed." 



In 1894 Kinney (68) stated that the skins and stems of pears 

 which had been sprayed five times with Bordeaux mixture (6 pounds 

 of copper sulphate, 4 pounds of lime, and 22 gallons of water), and 

 upon which the spray was still visible at harvest contained only 

 0.016 grain of copper oxid per pear, for which reason no serious 

 objection to this treatment could be raised from a hygienic stand- 

 point. 



In 1894 Garman reported (49) that the skins and ends of six apples 

 from a tree that had been sprayed once with London purple and five 

 times with Paris green at the rate of 1 pound to 160 gallons of water 

 showed on analysis no arsenic and only an unweighable amount of 

 copper. The flesh and cores of these apples gave no reaction for 

 arsenic or copper. He reported also (50) that cured tobacco which 

 had been sprayed with arsenites, at the rate of 1 pound to 160 gallons 

 of water, gave on analysis 0.077 grain of arsenious oxid and 0.042 

 grain of copper oxid per pound with one spraying with Paris green; 

 0.133, 0.259, and 0.329 grain of arsenious oxid and 0.126, 0.210, and 

 0.322 grain of copper oxid per pound with two sprayings with Paris 

 green; and 0.245 grain of arsenious oxid per pound with two spray- 

 ings with London purple. Later (1904) this author stated (51) that 

 arsenites such as Paris green can be used on cabbage without leaving 

 a trace sufficient for recognition by the chemist. In 1901, cabbages 

 which had been sprayed with Paris green or lead arsenate showed on 

 analysis "traces of poison present." In 1902, and again in 1903, 

 sprayed cabbages were analyzed, but the chemist "was unable to find 

 a trace of poison present." 



In 1897 Teyxeira (123) found from 20 to 50 milligrams of copper 

 in 1 kilogram of juice from tomatoes that had been sprayed with 

 copper sulphate, and none after treatment with Bordeaux, unless 

 the skin was cracked. He stated that the copper sulphate penetrates 

 the skin into the flesh, but that; the copper-lime mixture does not. 



