Two Letters on "Seasonal Distribution of Soil and ... - ACS Publications

In a very interesting article by M. Greenfield and W. N.. Skourup on "The Seasonal Distribution of Soil and Fecal Strains of the Colon-Aerogenes Group...
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T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING C H E M I S T R Y

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NOTES AND CORRESPONDENCE TWO LETTERS ON “SEASONAL DISTRIBUTION OF SOIL AND FECAL STRAINS OF T H E COLON-AEROGENES GROUP IN SURFACE WATERS” Editor of the Journal of Industrial and Engineering Chemistry: In a very interesting article by M. Greenfield and W. N. Skourup on “The Seasonal Distribution of Soil and Fecal Strains of the Colon-Aerogenes Group in Surface Waters” published in the July, 1917, number of THIS JOURNAL,the conclusion is reached by the authors, on p. 678, that “there seems t o be no difference between soil and fecal strains of organisms of the colonaerogenes group from surface water supplies in their resistance to treatment.” I n interpreting the data submitted in the article, however, it would seem to the writer that the above conclusion is not quite justified. As far as can be judged, Miss Greenfield and her co-worker have based their conclusion upon a n interpretation of the total percentages of soil and fecal strains without regard to the findings in the raw and treated waters of individual cities. If the data are analyzed with reference to particular sources and to the effect of treatment upon the different types of waters, a very complete selective action may be found to exist. In order to make clear the presence of a distinct differentiation of action by treatment of these surface supplies, I have taken the liberty of summarizing the data found in the article, in Table I. The interpretation of these results may be made

TABLE 11-INTERPRETATIONOF SELECTIVEACTION B Y TREATMENT O F CERTAlN KANSAS WATERS (Wolman. July, 1917) STRAINS ONLY-FECAL Rain Drouth Probable Scoring of SeProbable Scoring of SeDegree of Resistance lecDegree of Resistance lecof Organisms tion of Organisms tion City in Raw Water Ratio in Raw Water Ratio 2.4 A-Least Resistant 1.6 Cherryvale. . A-Least Resistant Humboldt.. B 1.4 B 1.4 C 0.8 C 1.2 Chanute.. . , , Independence.. D 0.4 D or B 1.5 Coffeyville.. E-Most Resistant 0.3 E-Most Resistant 0.8

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done in Table 11. That the gradation of the scoring is a reasonable one, we may venture to assert because of the following conditions. The raw water of Cherryvale would probably contain the least resistant forms of bacilli because it is polluted by raw sewage a t a distance of only 20 miles. The effect of the storage of five days on the Cherryvale supply is problematical in this connection, although it would tend possibly to increase the resistance of the surviving bacilli. The scoring of the Humboldt supply seems reasonable when it is noted that the source of its pollution (even though subjected to preliminary treatment) is only 8 miles away and also relatively great in its extent. It would appear, therefore, that this raw water should contain bacterial forms of quite low resistance. The Chanute raw water, upon a similar basis, should show a slightly higher degree of resistance in its bacilli. Independence and Coffeyville may be assigned fourth and fifth places in this system of scoring, since the former has been exposed to raw sewage polluTABLE.I-DISTRIBUTION OF FECAL AND SOIL B. Coli. RESULTS IN PER tion, but a t a distance of 24 miles, while the latter should unCENT OF TOTAL BACILLI (Adapted from Greenfield and Skourup. THISJOURNAL, 9 (1917). 676) doubtedly contain the most resistant forms of bacilli, since its RAIN -DROUTHsewage pollution is farthest away and subject t o the highest -Fecal-Soil-Fecal-SodCity Raw Treated Raw Treated Raw Treated Raw Treated degree of treatment of any of the five contributory sewages, Independence.. 1 2 . 4 33.17 8 7 . 6 6 6 . 8 87.5 60.0 12.5 4 0 . 0 factors which would tend to inhibit the appearance of less reChanute.. , . . , 5 0 . 0 5 9 . 9 5 0 . 0 40.1 56.5 45.7 43.5 5 4 . 3 Cherryvale .... 6 3 . 4 2 6 . 6 36.6 73.4 61.8 38.2 37.8 65.2 sistant forms in the Coffeyville raw water supply. In periods 76.2 8 2 . 8 Humboldt ... , 2 3 . 8 1 7 . 2 60.0 43.5 40.0 56.5 of drouth, a similar grading of resistance and selective action 86.7 5 9 . 9 Coffeyville ..... 13.3 40.1 52.4 66.7 4 7 . 6 33.3 NoTEs-Humboldt raw water had by far the more sewage pollution. is possible, but modifications in interpretation are necessary Cherryvale raw water collected after five days storage. Independencein order to readjust the probable degree of resistance of surviving only a small number of samples during drouth. Treatment of above waters consisted of coagulation with alum and rapid sand filtration. Indeforms of raw water bacilli. pendence also uses lime at times. SOURCESOF POLLUTION-Cherryvale-rsw sewage (20 mi.). IndeThe conclusion which the writer would like to indicate, therependence-raw sewage (24 mi.). Coffeyville-septic tank and contact fore, is that the treatment of these Kansas surface water supbed effluents (24 and 30 mi.). Humboldt-septic tank effluent (8 mi.). Chanute-Septic tank eBuents (8 and 16 mi.). plies apparently does exhibit a degree of selection between fecal soil strains of bacilli, which may be correlative with the and considerably easier by using a numerical measure of selective action of treatment upon soil and fecal strains, which we shall resistance of the particular forms and with the nature of their name the “ratio of selection” and which may be defined as the origin. Since the action of a rapid sand filter upon resistant numerical ratio of the percentage of total bacilli (fecal or soil, and non-resistant forms of bacteria would be, in all probability, as the case may be) in the raw to that in the treated water. non-selective, it might be well to search for the selective actions illustrated above in the devitalization effect arising in the process Using the above ratio, we may test the selective action of treatof coagulation and sedimentation preliminary to the actual ment in the case of the various cities cited in Table I. The filtration. presence or absence of this selective action will be evidenced ABEL WOLMAN, MARYLAND STATE DEPT. OF HEALTH equally as well by the use of the fecal or the soil strain percent16 W. SARATOGA ST.. BALTIXORE. RID. Division Engineer ages, since these are comparable, in each case, in a n inverse July 12. 1917 degree. For the purpose of this discussion, the fecal strains *......., only are considered. In Table I1 the calculations of the “ratio of selection” have Editor of the Journal of Industrial and Engineering Chemistry: been made and arranged in the order of descending selective The note from Abel Wolman, Division Engineer, Maryland action. The table indicates a t once, not only the presence of a State Department of Health, in which he criticizes the article well-defined selective action, but also an apparent gradation of on “The Seasonal Distribution of Soil and Fecal Strains of the selection by treatment, an explanation for which may be found Colon-Aerogenes Group in Surface Waters,’’ published in the in a study of the five types of raw water used. Since these raw July, 1917, number of THISJOURNAL, is very interesting. Cnwaters, ineachcase, havebeensubjected to approximately the same fortunately, Mr. U‘olman misinterpreted the terminology of type of treatment, we can attribute probably the varying selec- the authors. A treated water is one coagulated with alum only, tion to the variable resistance of the raw water bacilli. A study and a tap water is the finished product, that is, a water coagulaof the data regarding the character and source of pollution in ted with alum and filtered through a rapid sand filter. By each of the raw waters seems to the writer to offer sufficient using the numerical ratio of the percentage of total fecal bacilli justification for a system of scoring of the bacilli in these sur- in the raw to that in the tap water, very different results are face supplies upon a basis of relative resistance. This has been obtained.

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Table I gives the percentage of fecal strains in the raw and tap water, Mr. Wolman’s scoring of the degree of probable resistance of organisms in the raw water, and the selection ratio. I agree with Mr. Wolman’s scoring of the degree of resistance of organisms in raw water with the exception of Cherryvale. It seems reasonable to assume that only very resistant organisms would remain after five days storage. TABLE I-INTERPRETATIONOF SELECTIVE ACTIONBY TREATMENT OF CERTAINKANSASWATERS -FECAL STRAINS ONLYWolman’s scoring of -RaincDrouthprobable degree of Per Per SelecPer Per Selecresistance of organisms cent cent tion cent cent tion CITY in raw water Raw Tap Ratio Raw Tap Ratio

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Table I shows that there is a difference in the resistance of t h e fecal strains from the several cities but that this selective action is not consistent with the variable resistance of the raw water bacilli. I n other words, there is no way to prophesy, given the source of pollution, the percentage of fecal bacilli that will resist the treatment. M. GREENFIELD A N D W. N. SKOURUP STATE BOARDOF HEALTH LAWRENCE. KANSAS

NITRATE SUPPLY COMMITTEE-CORRECTION Owing t o a typographical error, the investment cost of the Haber Process when ammonia is the product [see table, THIS JOURNAL, g ( 1 9 1 7 ) , 8411was made to read $540, when it should CHARLESL. PARSONS read $340.

WASHINGTON LETTER

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BY PAUL WOOTON, Metropolitan Bank Building, Washington, D. C.

With such matters on the tapis as the location of the nitrate mittee on Chemicals of the Council of National Defense, finds it difficult to understand the delays in official action. The fact plant; the investigation of the defective primers manufactured a t the Frankford arsenal; the important progress being made that the selection of the site for the nitrate plant is being deferred in the study of noxious gases and the materials used in the from week to week is giving much concern to Dr. Nichols, who characterizes the handing over to the government of the General manufacture of submarines, aeroplanes and balloons ; the pyrite Chemical Company’s synthetic ammonia processes as the greatest and manganese situation and the important information gleaned at the Boston meeting of the American Chemical Society, sacrifice he ever made. He pointed out that the General ChemiWashington chemists have had much food for thought and cal Company has been working on this process since 1911and, a t the time of the government’s appeal, had allotted a large sum subject matter for discussion during the past month. Rarely has there been such a demand in Washington for a of money to build a plant for the carrying out of the process on a publication as that evinced for the September issue of THIS large scale. He said the only condition which the company had JOURNAL.Despite the fact that proofs of the article on the stipulated was that the government take adequate steps to nitrate report had been delivered in advance to the four daily safeguard the company’s confidences. He also called attention newspapers published in the capital, nothing in regard to the to the fact that the company is not receiving a penny for the use of its processes and that they had been turned over with the report was published. The only available copies of the report were those contained in the Journal. The demand for the re- sole intention of being helpful to the country. port became so great that a week following its publication in That a knotty chemical problem which will have to be solved the Journal, the Committee on Public Information issued a by the special board consisting of Col. Worth Robinson, prostatement containing some of the more important phases of the fessor of chemistry a t the U. s. Military Academy, Dr. H. P. matter. Talbot of Massachusetts Institute of Technology and Dr. Chas. The failure of the newspapers to print the results of the nitrate L. Parsons, secretary of the American Chemical Society is ininvestigation led Representative Longworth, of Ohio, on Septem- volved in the failure of certain primers manufactured a t the ber 14, to address the House on the subject and to have the Frankford arsenal became very evident during the course of the complete report printed in the Congressional Record. Mr. investigation conducted by a special congressional committee. Longworth considered the action taken “of vast, if not vital, H. C. Pritham, the chief chemist of the technical staff a t the importance to the safety of the nation and to our continuance arsenal, testified that a number of causes contributed to the as a potent factor in this war.” failure of the primers. Principal among these were: the presence Continuing, Representative Longworth said : “My other of impurities in the ingredients; improper granulation of materials; object, far more important, is to show that a situation has been overcrowding in the dry houses; and irregularities in manufacture. brought about by the intelligent action of this Government, The particular impurity which Mi. Pritham held largely rewith the assistance of a number of prominent American engi- sponsible for the trouble was potassium bromate in the potassium neers and scientists and chemists, by which the country is chlorate. “Primers may shoot fine when made,” said Mr. assured during this war, no matter what may happen, regardless Pritham, while on the stand, “but the potassium bromate will of whether or not we may by some chance be cut off from the cause a slow deterioration. We do not know whether it is a Chile nitrate supply, of an absolutely sufficient and cheap catalytic action or whether it is simply a decomposition with supply of nitric acid, without ‘which it is impossible to make the liberation of the bromine and the generation of sulfuric ammunition or explosives of any kind, without which we would acid. The presence of the bromate is a result of impurities in be impotent in the conduct of a war, either defensive or offensive, the original potassium chloride from which the chlorate was and without which the enormous amount of money appropriated made.” in this bill would be absolutely useless. This happy situation After explaining how war conditions have cut off the supplies is better summed up than I could sum it up in a letter written of chlorate usually relied upon in this country, Mr. Pritham by Dr. Herty, formerly the president of the AMERICAN CHEMICAL said: “The chlorate made in the United States carries a higher SOCIETY,now the editor of the official organ of the AMERICAN percentage of impurities. During manufacture the bromate CHEMICALSOCIETY,known as the Journal of Industrial and is not eliminated; that is, it occurs as bromide and is oxidized to Engineering Chemistry, and a member of the committee ap- the bromate and crystallizes out with the chlorate in the ordinary pointed by the Secretary of War to investigate this question. process of manufacture. The improved process which Major In a letter written to the editor of the Manufacturers Record Cushman has been working on, will be a very simple way of and published a few days ago he says:” Representative Long- getting rid of the bromate. All the chlorate on hand a t the worth then read excerpts from the letter. arsenal has been shipped away t o be treated by the new process. After recounting how Dr. Chas. I,. Parsons (secretary of the Previously no one had paid any particular attention to this matter American Chemical Society), whom he designated as “one of the because nobody had any information or had demonstrated t h a t great chemists of the country,” has investigated nitrate manu- bromates formed a deleterious ingredient in a primer.” facturing methods in Europe, Mr. Longworth said: “The Mr. Pritham was graduated from the Chemical and Engineeroutstanding feature of the action officially taken is the postponement indefinitely of the proposition to make nitrogen in any ing Department of the University of Maine in 1901. Walter Arthur, the research metallurgist for the Titanium form by the use of water power. This, thank goodness, gentlemen, sounds the death knell of that Muscle Shoals $zo,ooo,ooo Alloys Manufacturing Company, who made an examination of some of the primers for the War Department, told the comnitrate scheme.” Accustomed as he is to the high standard of efficiency in his mittee that the trouble resulted wholly from too coarse granulation of the antimony sulfide and the potassium chlorate. “NO own organization, Dr. W. H. Nichols, chairman of the Com-