Document 1QEm8J6LD10RgKxG5m4MEE29o

WATER CANS ) 0022671 metimmsi of tssxs oh vm sb cxm9 5 Q&UJSSi GiMSHimSD. 1. physical Condition of Cans. Upon receipt the slat cans were all dull dark gmy on th outside, tho result of a "pickling" process. Throe of the cana ware "pickled" csa the inside as well; the other three shewed the bright finish and characteristic rosette appearance of galvanizing. Caps on all cans were !ifroze" and difficult to rasamro. 'frideneo of corrosive action on th threads of e&p and nipple was present. \/ A white powdery coating varying frost slight to fesiavywas present in all cans. Is some large floes of whitish precipitate were adherent to the alls. Prior to any tostins, the cans wore thoroughly scrubbed with calgooite sad hot water, usins brushes with hair sr fiber bristles only. After each succeeding use, -tli cans were similarly scrubbed. The cans could not be completely drained because of th inward directed threaded nipple. Approximately three ounces (89 to 99 we) of water rersainsd after the sosi eosaplete emptying possible. To facilitate complete drainage a inch hoi was bored through the top of tho can just at' tm shoulder bolow the regular opening. 2. Analysis of base metal and coating. a. Base metal - low carbon stool b. Coating - physically stripped fro a can,, th top of which was sawed off: Zinc Iron 55.3 $ 2.9 Load 1.03 ' Antimony 0,23 Total recovery 99.^3^ 3i Cfcssg in reaction of waters in the cans. (AH pE determinations made electrometrically) a. Mattiled water - preliminary tost. T i m In can pH Initial 3.4 After 1 min. 6.0 " IS hra. 8.6 " 2h hra. 8.6 KE 0022672 Tine ia can After48bars* pa 8.8 o'* DistilledIwater - collected directly f^ca still with aoda lise eomecteaIanittoiaelxc'l.ude COg air. g.4 Aft1n5er 42184aihhaarr.s.. 58T...696 2a the abe throe roas, 6 liters of water sed each tino. The cans were allowed to stead, without shaking, at roosa temperature. Only in (3) was any attempt made to exclude COg. d. Furtlser definitive deterainaticai of pH was sad for the purpose of correlating reaction with solution of the coating natal. The waters used, time elapsing and pH are shown in the table below* Change in pH `C M T -C" -"m&tillsd"--- Can "D" 'lap------- Oan^C" Distilled--------- C S a ^ ^ T d p -------- 7/ater Water water & 1 ffj$f Chlorine water & 1 PPM Chiarine Elapsed Tim uH Elapsed Tine pH _rilapsed Time . PH.... Elapsed Tim Pi Initial 'lasjeiiato 2 Mia. 6 Min. io- Mia. 18 Min. 26 Min. 42 Min. 74 Min. 138 Mia. 2 6 6 Min. 24 Era. 5.7 6.0 6.0 3 6.10 6.15 6.40 6.40 6.50 6.50 6.60 6.60 7.15 .Initial -^assediata 13 His. > 30 Min. 150.Hin. 4 Srs. : 24 Era. 7.9 Initial 8.0 Xasasdiat 8.15 13 Mia. 8.29 50 Min. 8.25 45 Min. 8.40 73 Mia. 8.75 IO? Mia. 24 Ers. 6,6 -6 .8 5 7.0 7.2 7.2 7.2 7.25 . 8.25 Initial ^Insediate 15 Min. 30 Mia. 1 Hr. 4 Era. 6 Ers. 24 Era. 7.85 8.0 0 8 .10 8 .13 8 .13 8 .23 8 .30 8 .43 >issasdlato Essane that a sassole was withdrawn as soon as possible after introducing the water into the can. m all instances 10 liter quantities were used and prior to sanpling the cans were rigorously shakes in addition to being shaken at intervals during the test in order to reduce the ssaunt of COg in solution. Hf. 0022673 4. Evidence of chemical action on coating asstal. . Distilled water - not chlorinated. After 24 hours the water was very faintly silky with floes of a heavier sodicxmt which adhered to the sides of a glass vessel, fetches of white deposit could he seen in the can. b. Tap water - not chlorinated. After 24 hours id water was very silky and contained a white sediment in particles of varying else. InsIdo of can showed many patches of whit deposit. ai'tsr 2k hra. with a considerable amount of heavy white precipitate. d. Tap water, chlorinated, 1 PPM. Free chlorine disappears rapidly. {Bee table). Water very cloudy after 5k hours, with large amount of heavy white sediment. la the four testa above, it was observed that the portion of the can covered by water was distinctly warmer than the metal above the water level. This would indicate an exothermic reaction, probably galvanic in nature. Upon opening the cans there was a musty, metallic odor and the waters all had a distinctly metallic taste. 5. Loss of free chlorine - Remaining concentration in ?PM, Can Run Water AA *1 Distilled 2 it A5 3 A* *i n B2 -t B3 ? 1 Tap 2 Time in Minutes Initial 10 1.0 o.h 0.4 0.5 0.1 0.5 0.15 0.15 1.0 0.5 0.4 o.5 0.1 0.5 0.2 0.15 0.5 0.2 0.1 0.2 0.1 0.05 15 0.25 0.1 0.5 0.1 50 cO 0.1 0.05 0.05 0.1 0.02 0.1 0.05 0.1 0.05 0.0 150 0.0 0.0 0.0 0.0 0.0 0.0 0.0 la can "3" some of the base metal was exposed due to breaking of "blis ters" of the coating metal. As soon as base metal (iron) is exposed a gal vanic action is set up and the typical moth eaten appearance is produced, followed by rapid rusting of the base aetal. Can "A" showed no visible breaks in coating. Can "C" is one from which the top was cut upon receipt and from which coating metal was stripped for analysis. Using a dental abrasive disc, the coating was removed from four circular areas on the bottom of the can, each Jr inch in diameter, to set up an artificial condition such as later occurred spontaneously in can "B". 6. Zinc content of water from cans. Quantitative determinations of zinc, lead and total solids are not yet completed, but qualitative tests show that zinc is dissolved from the gal vanized lining by distilled water, plain and chlorinated, and by tap water, plain and chlorinated. 7. Conclusions. a. Water, chlorinated or unchlorinated, after storage for 2k hours in the galvanized water cans is unpalatable in appearance and taste. This is due in part to the actual solution of zinc by the water and in part to the resultant precipitation from solution of calciua and magnesium salts naturally present. b. Ho conclusions as to the offact on the health of individuals con- 3 ta3 ins such water can be drawn at the present time. However, should lemon ade, or other mildly acidic beverage be placed in such cans, sufficient sine would bo put into solution to produce severe symptoms of gastro-entoritis in individuals using the beverage. G. J . GFNTZKOV, I t C o l o n el . M edi cal Cor ps, C h i ef Bi ' ' M on o f Chem 1a t r y * p h y si c s. K 0022675