1036 



FOODS AND FOOD ADULTERANTS. 



for from these lead and tin may be simultaneously dissolved. In 

 any case the difference in the affinities is too slight to allow the con- 

 sumer to implicitly rely on it to save him from the effects of the can- 

 ner's greed. Lead poisoning is a serious thing and no chances should 

 be taken. 



In Germany the laws relative to the composition of alloys used for 

 plating tinware are rigid. The law of June 25, 1887, l reads : 



" $ 1. Cooking, eating, and drinking vessels, as well as measuring vessels for fluids 

 * * * shall not be tinned with an alloy containing more than 1 part of lead in 

 100 parts, nor be soldered with an alloy containing more than 10 parts of lead in 100 

 parts by weight. 



"The tinning on the interior of cans for preserving food must satisfy the require- 

 ments of 1." 



The plating alloy of a few cans from the pea samples was examined. 

 In most cases lead was present. The quantity found varied Avithin tol- 

 erably wide limits, as may be seen from the subjoined table: 



Per cent of lead in plating alloy. 



The results shown under Nos. 10699, 10702, and 10703 were all from 

 cans packed by a single firm whose goods are widely sold in Washing- 

 ton. No. 10699 cost 13 cents per can and No. 10702 10 cents, but No. 

 10703 was sold at 18 cents, thus enabling the packer to use a better 

 quality of tin. Nos. 10700, 10706, 10708, 10709, 10710, 10882, 10891, 

 10900, and 10980 are all bad. No. 10891 was put up in France. 



In regard to the methods of analysis usually given for the detection 

 of lead in tin plate and for the analysis of the coating alloy, it may be 

 said that they are unsatisfactory. Pinette 2 proposes to attack the tin 

 coating with dilute nitric acid, decant the fluid and suspended matter 

 from the residual iron, evaporate to dryness on the water bath, take up 

 with nitric acid, filter and weigh the tin oxid, and in the filtrate esti- 

 mate the lead as sulphate, Results are calculated by adding the 



1 Quoted by .1. Pinette, Chein. /tg.. 1S!M, 15, 1 10!>. 

 "Chun, /tg., Will, 15. U>L>X. 



