A Question of Water, Ethics, and Bacteria. BY Prof. ALBERT R. LEEDS, Ph.D., STEVENS INSTITUTE. FROM THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES, March, 1893 Extracted from The American Journal of the Medical Sciences, March, 1893. A QUESTION OF WATER, ETHICS, AND BACTERIA. By Prof. Albert R. Leeds, Ph.D., STEVENS INSTITUTE With our daily growing knowledge of the etiology of disease, and the discovery of the fact that the water which we daily use in our homes and houses is the most widely diffused and general bacterial culture- fluid, the feeling of responsibility connected with water diagnosis steadily increases. After an experience of twenty years, during which I have reported upon somewhat more than two thousand samples sent from a large proportion of our public supplies, and representing the most diverse kinds of water, I feel a more painful sense of this respon- sibility, and am at times more embarrassed in arriving at a decision than when I made my first analysis and report. This was upon the waters used by Jersey City, Newark, and Hoboken some twenty years ago. An interesting experience of this nature has recently befallen me. It involves not only a question of ethics and moral obligations, but also certain doubts as to the practical value of bacteriology in deciding upon the wholesomeness and purity of a water employed for domestic use. A sample of water was sent by a well-known engineer which had been taken from the well of one of his clients, whose house stands in perhaps the most beautiful of the residence-parks of suburban New York. It had so happened that the water of another well, located in the same park, had been sent just previously, and though affording better ana- lytical data, had been condemned as dangerous and impure. But the water of the particular well I now refer to, for reasons given below, was pronounced safe and wholesome. To put the matter in clearer light, I shall run the risk of making my article somewhat formidable with technical terms and with figures, and shall give in detail the relative composition in parts per 100,000 of the two well-waters: Condemned water. Approved water. Color ....... . Same Same Taste . . Pleasant Sparkling Smell . . None None- Ammonia ...... . 0.006 0.0045- Albuminoid ammonia , . 0.008 0.0115- Oxidizing oxygen . / ' . 0.071 0.20 Nitrous acid . . i. . . / !. . None Trace Nitric acid . . \. X, * W , ]■ t \h\07 4.008 Ch,oriM ■ • ■ . y.> 0/525 0.575 2 LEEDS: WATER, ETHICS, AND BACTERIA. Condemned water. Approved water. Total hardness .... . 7.65 10.25 Permanent hardness . 2.45 6.00 Temporary hardness . 5.70 4.25 Total solids .... . 13.10 23.13 Mineral matters . 9.10 19.80 Organic and volatile matters . . 4.00 3.33 Dissolved gases measured at 0° C. and 7.60 mm. pressure: Condemned water. Approved water. Oxygen . . . 6.15 cub. cent. 6.56 cub. cent. Carbonic acid .... . 9.47 " 23.53 " Nitrogen . 13.87 15.19 " Total gases .... . 29.59 " 45.28 " Colonies of bacteria per cub. cent. . . . Innumerable 1674 The very pleasant taste of both waters, which in the approved arose to a lively sparklingness, like mild mineral water, was due to two causes: in part to the high percentage of salts, but still more to the great amounts of nitrates and of carbonic acid gas. Peculiar interest and significance are connected with the presence of these acid substances in such large quantities on account of the way and manner in which they were originated. Unquestionably they sprang from manure and sub- stances of the nature of sewage which the water took up in its passage through the soil on its way to the well. Nitric acid is derived from sewage by the oxidation of its nitrogen and ammonia. And, lest any- one think there is a blunder in reporting this enormous quantity, amounting to 2i grains to the gallon, let me say how it was determined. After trying for years the various customary methods of estimating the nitric acid in potable water by means of its reduction to the form of nitro- gen and ammonia, by the indigo and other methods, I have given up all these methods, believing them to be untrustworthy. Instead of employing these methods, I reduce the nitric acid to the form of nitric oxide gas, and then measure the latter in a eudiometer. In this instance the nitric oxide obtained from i litre of the water, after its volume had been reduced to the normal temperature and pressure of 0° and 7.60 mm., amounted to 8.305 cubic centimetres. In order to prove that this great volume of gas was nitric oxide, and not some nitrogen or other gas re- sulting from extraneous substances, or some error in the conduct of the experiment, I passed up into the eudiometer a proper amount of oxygen gas. Nitric oxide has the property of combining with oxygen to form a dark-red gas known as nitrous acid. This is a most striking and characteristic phenomenon. On making the test with oxygen, these blood-red fumes appeared. The fumes were entirely absorbed by caustic soda, showing that no other gas than nitric oxide had been originally present, and all that was present in the eudiometer was derived from the nitric acid of the water. Though almost incredible, there could be LEEDS: WATER, ETHICS, AND BACTERIA. 3 no further question of the fact-2i grains of nitric acid to the gallon was certainly present in the water. The carbonic acid came from sub-aerial oxidation of the carbon of organic matters, which, as I have already stated, consisted in this instance almost entirely of manure and sewage. To realize how excessive is the amount, call to mind the fact that the carbonic acid in New York City water varies from 9.50 c.c. in midwinter to 2.5 c.c. in late summer and autumn. Also, that the well-waters in its vicinage, which are ordinarily soft, contain only 3 to 5 c.c of carbonic acid. But the feature sui generis was the nature and number of the bac- teria. In both cases these bacteria belonged to a class which is known as nitrifying ferments. It has been definitely ascertained of late years that the direct oxidation of nitrogen and ammonia to nitric acid very rarely, if ever, occurs in nature. It is necessary to have the aid of minute living organisms, which are known as nitrifying bacteria, to effect this change. They act as ferments, similar to the way in which the yeast plant brings about the conversion of sugar into alcohol and carbonic acid. The absorption of oxygen is an essential and necessary part of the discharge of the vital functions of these nitrifying bacteria. They cause the oxygen to combine with the nitrogen of the ammonia and albuminous substances which are present, these substances disap- pearing, and their place being taken by nitric acid. The number of bacteria in the condemned water was greater than I could count on the culture plates. The approved water, on the con- trary, exhibited 1674 colonies per c.c. Just here came the rub. Pro- fessor Koch has set down 50 bacteria per c.c. as being, in his opinion, the limiting number which should be present in any water that is to be accounted wholesome and potable. As to the extent of his practical familiarity with water-supplies I have no knowledge. Wolfhiigel found that the bacteria in the water of the Spree, from which a large part of the water-supply of Berlin is derived, were reduced by filtration from 3000 colonies in a c.c. to an average number of 107 colonies. This is by the use of the gravity filters constructed after the pattern of those commonly used in England. These filters are cleansed by scraping off the deposit of filth which forms on the upper surface of their filter-beds of sand. Their action is very slow. To show how different is their operation from that of the mechanical filters now extensively used in this country, I shall mention a few facts which are not generally known to the medical and engineering professions. At the present time the only method by which the city of Philadel- phia can be supplied with pure water at a moderate and reasonable outlay, is by means of filters erected at the pumping stations on the Schuylkill and Delaware Rivers. The plans for obtaining a supply from the upper Delaware, from the Tohickon, the Perkiomen, and the 4 LEEDS: WATER, ETHICS, AND BACTERIA. upper Lehigh, proceed upon the assumption that these water supplies are necessarily pure and can be kept so. This assumption is utterly false ; it is not borne out by the facts. Moreover, the expense of obtaining a supply from these sources, involving, as it does, the claims of certain syndicates which control water rights, and the building of immensely long conduits, would be enormous. In case the city deter- mines to supply filtered water, the New York Filter Company has guaranteed to run a filter plant at the Belmont pumping station with a capacity adequate to filter twenty million gallons of Schuylkill water per diem. Moreover, in case the number of bacteria at any time during the course of trial of a year's duration exceeds 100 per c.c., the company forfeits the payments of the contract price, amounting to nearly a quarter of a million of dollars, and obligates itself to remove the plant without charge of any kind to the city. As chemist of the Philadelphia Water Department for a number of years, and knowing the effect on the Schuylkill River of the sewage of Manayunk, Conshohocken, Norristown, Phoenixville, and a population of 300,000 people located in the drainage area above these manufacturing towns, I can assure my readers that in guaranteeing to cut down the bacte- ria to a lesser number than that found by Wolfhiigel in the Berlin filtered waters, this company has undertaken to achieve a most important result, and that, too, on a stupendous scale. Dr. Chapin, the health officer of Providence, R. I., has found, however, that this result, and a still more perfect one, is constantly attained in practice. A similar filter plant delivering two million gallons per diem, at Long Branch, N. J., supplies water containing, not 100, but only 2 to 5 colonies of bacteria per c.c. This is by the use of a filter which is washed thoroughly twice in every twenty-four hours. The bacteria, by the use of aluminic sulphate, are entangled in a magma of aluminic hydroxide, and filtered out along with the precipitated coloring matters, clay, etc. I have analyzed the waters of Long Branch before and after filtration, with the following results, which are stated in parts per 100,000: Before filtration. After filtration Free ammonia ..... . 0.132 0.0035 Albuminoid ammonia .... . 0.0445 0.0095 Oxygen required to oxidize organic matters . 1.232 0.1785 Nitrous acid . 0.0025 0.0015 Nitric acid ...... . 0.087 0.087 Chlorine . 0.35 0.35 Total hardness . 2.25 2.25 Permanent hardness .... . . 0.00 1.00 Temporary hardness .... . 2.25 1.25 Total solids ...... . 9.52 7.14 Mineral matters ..... . 5.28 5.40 Organic and volatile matters . 4.24 1.74 6 LEEDS: WATER, ETHICS, AND BACTERIA. In other words, the free ammonia was diminished to the one-thirty- third part of its original amount; the albuminoid ammonia to one-fifth, and the oxidizable organic matter to the one-seventh. To bring about this marvellous purification sixty-five one-hundredths of a grain of alum to the gallon was used. The alumina acting as a coagulating material had been so perfectly removed along with the dirt, bacteria, and coloring matter that it was practically absent in the filtered water; if present at all it could only be recognized by the application of the most delicate chemical tests. It is interesting to know what was the original source and nature of the water-supply of Long Branch. It comes from a peat bog located in a cypress swamp about four miles west of that watering- place. It had, on my color scale, July 8, 1892, seven degrees of color, and appeared like an infusion of coffee. And while it had a bitter, peaty taste, the filtered water was perfectly colorless, without odor, and pleasant to the taste. The almost complete removal of bacteria effected by these filters is in one sense a misfortune. Bacteria are Nature's physicians, constantly busying themselves in seeing that the decomposing and worn-out parti- cles, which would otherwise clog the machinery of Nature, are gotten out of the way and resolved into their simple and harmless elements. They are universally present: in the air, in the earth, and in the waters under the earth. They dwell with the trout in the waters of the purest moun- tain torrent and are found at the bottom of the coldest and deepest well. As to the moss-grown bucket, the oaken-bound bucket, its moss and oaken chinks and crannies are for bacteria a paradise. Frequently in a sample of milk, when fresh, I have found many hundreds to the tea- spoonful, while in the course of a few hours their number has increased to millions. With their aid it is possible to make good cheese, and each one of its peculiar and delicious flavors, from the pianissimo of cottage cheese and Brie, through the crescendo of Stilton, Gorgonzola, and Roquefort, and up to the fortissimo of the indescribable Limburger kiise, is due to its particular and peculiar flavor-developing bacteria. The choicest gilt-edged Darlington butter owes its aroma and dainty taste to cream ripened by bacteria under choice and dainty conditions. The human mouth, stomach, and intestines contain bacteria in im. mense numbers and variety. Recently I counted the bacteria in my own saliva six hours after eating. There were 10,775 colonies per cubic centimeter. If we assume that a litre is secreted daily and that it con- tains the same average number, we should have the enormous aggregate of over ten million bacteria. Some of the bacteria of the alimentary tract have a peptonizing action, converting the proteids of the food into peptones; others are diastatic, splitting cane-sugar into dextrose and laevulose. Some have a reducing action, breaking down albumin into the products of fermentation and putrefactive decay, with the evolution of LEEDS: WATER, ETHICS, AND BACTERIA. 7 hydrosulphuric acid, ammonia, etc. These are more especially active and abundant in disordered conditions of digestion. The reducing action of ■other varieties is exerted upon the fermentable sugars of the food, decom- posing them into lactic and carbonic acids. I have never examined the saliva without detecting the presence of nitrous acid due to the reduction of nitrates by the bacteria. At the same time that the counting of the bacteria above alluded to was made, I found my saliva contained 0.4 milligramme of nitrous acid in 100 cubic centimeters. Considering, then, the peptonizing, soluble-making, reducing actions of these alimentary bacteria, is it not eminently probable that they are intimately concerned in, if not essential to, the processes of digestion ? Unfortunately, among the countless multitudes and species of bacteria, which are the gardeners par excellence in the garden of Nature, working ever toward making it sweet and pure for man's indwelling, there are some which are too vigorous and hasty in their action for our immediate safety and comfort. These are the pathogenic, the toxic, the morbific genera, which tend to sweep away or extirpate any poorly nurtured, non-resistant, or diseased organism that comes in their way. Yet they are as abnormal, so to speak, as is disease itself. A thousand samples of milk taken at random will probably not show a single pathogenic bacterium. A thousand springs, wells, and watercourses might readily be found in our vicinity of which the same can be said. But inasmuch as the bacillus of typhoid and tuberculosis has been found in diseased cow's milk, the unfortunate recommendation was made to physicians some years since to sterilize all milk by long-continued heating to the boiling-point. The fad quickly became as universal as it was short- lived. It took on its acutest phase some two years ago, but to-day sterilized milk is no longer manufactured for sale in New York. The malnutrition and deaths due to feeding sterilized (i. e., by continued heating to 212° F.) milk to infants have a hundred-fold exceeded in number the cases of tuberculosis, scarlet fever, or other zymotic disease resulting from the bacilli of these diseases in ordinary good country milk. Pasteurized milk, which leaves the constituents of the milk in their natural condition, has taken the place of this tortured, over-cooked milk, in which scarcely a single element is left in its proper and digest- ible state. While the pasteurization of milk, or its heating for ten to thirty minutes at a temperature of 160° F., does not certainly destroy every germ, it reduces the probability of their presence to a minimum. So with regard to water. By long-continued heating it can be ren- dered absolutely germ-free. The same result can be effected by filtra- tion, provided the filtering medium is fine-grained enough and the rate of filtration is sufficiently slow. But with the materials and the methods essential to an economical supply of the immense quantities of water required by our great cities, no process of filtration ever has made, or 8 LEEDS: WATER, ETHICS, AND BACTERIA. in the nature of things can make, the filtered water absolutely germ- free or sterile. And even if it could, sterilized water is an artificial commodity of very questionable value. Experience has shown that such water, unless carefully kept in reservoirs as far as possible out of contact with light, heat, and air, spoils very rapidly. As soon as the spores, ever floating in the atmosphere, fall into it, they develop in the presence of warmth and sunlight with great rapidity, and the water so fertilized becomes filled with microscopic organisms, algae, etc. These, in their decay and by the production of foul tastes and odors, render the water unfit for domestic use. The reduction of the bacteria as far as can be practically accomplished by filtration, and not to the point of absolute sterility, is all that is necessary or desirable in an engineering plant designed to supply the water for the multifarious uses of a great city. This, indeed, is the system which has proven eminently satisfac- tory during the past thirty years for the supply of the five and a half millions of inhabitants of London. This city has 44 subsiding reser- voirs, covering an area of 465 acres, and an available capacity of 1,300,000,000 gallons. It has also 100 acres of filters, delivering 160,000,000 gallons daily of filtered water. No epidemic of cholera, such as repeatedly devastated London prior to the installation of its filter system, has occurred since the seven London water-companies were compelled in 1852, by Act of Parliament, to filter their water. In the fifty years prior to the passage of this act there had been four great epidemics, and they had all been traced by such overwhelming evidence to the drinking of unfiltered water that the compulsory installation of the filters had resulted in consequence. To-day the death-rate of London is lower than that of most cities, and the percentage of typhoid fever is correspondingly low. Having arrived at this conclusion, I wish to return to the question of ethics in relation to the significance of bacteria in water," which was the primary reason that induced me to write this somewhat lengthy article. What did my duty and a sense of moral obligation to the gentleman who had been at the expense of having his well-water examined require that I should do in face of such chemical and biological data as the analyses revealed ? It would not answer to report that the evidence as to purity or the reverse was conflicting in its nature, and as long as there was a doubt prudence demanded that he should not use the well, and that he should seek his supply of water from another source. A physician knows by hard experience that whatever may be his doubts as to the diagnosis, he must prescribe a course of action and treatment. It might be truly answered: Your duty was to confirm your diagnosis by every means in your power. Make culture experiments upon the separate colonies of bacteria until you were absolutely certain whether LEEDS: WATER, ETHICS, AND BACTERIA. 9 any pathogenic forms were present or not. My reply to this would be that such a search is a long, intricate, and difficult investigation, ending finally by establishing the probability of the absence of such forms, and not by arriving at an absolute certainty. Moreover, the expense and labor vastly exceeds the moderate fee which a client is willing to pay for a water analysis, and a charge commensurate for such an exhaustive investigation would be regarded as an extortion. I sent, therefore, for the engineer who had submitted the water, and requested him to acquaint me with the facts in the case and the location of the well in relation to cesspools and other possible sources of pollution. By refer- ence to the accompanying diagram, the facts which he made known will become easily intelligible. STABLE HOUSE >WELL CESS- HOUSE POOL SEWAGE FARM The well is located on the slope of a hill, and 20 feet and 100 feet, re- spectively, from a house and stable located farther down the slope. Above it are a house and a sub-surface irrigation field at distances of 35 feet and 150 feet, respectively. Between the house and the field is a cess- pool, stated to be cemented perfectly tight, and used to carry the house sewage by an intermittent flushing action upon the small sewage farm. This farm has an area of 100 square feet, with a sub-surface small drain-pipe system, the drains being 4 feet apart, and disposing of 1000 gallons of house sewage daily. These facts revealed by the engineer were strikingly in accord with the analytical data. By oxidation and nitrification the ammonia and nitrogenous matters in the house excreta were converted in the sewage 10 LEEDS: WATER, ETHICS, AND BACTERIA. farm into immense amounts of nitric and carbonic acids. The work was being very perfectly performed, as was shown by the very small amount of free ammonia and the mere trace of nitrous acid. The presence of so large a number of nitrifying bacteria was simply a guar- antee that their work of destroying the dangerous matters in the sewage was being very conscientiously and thoroughly performed. Had they been absent, the original sewage would have appeared in the well Moreover, it is well established that the bacillus typhosus and other pathogenic germs are themselves the food of the saprophytic varieties. Having assured myself by these considerations that the water in the well was not dangerous, I drank it myself freely during a period of two weeks, and then gave the owner a certificate, stating that the water had proven safe and wholesome. At the same time I advised the ex- amination during the cold weather to see whether the nitrifying bacteria were certainly doing their work during the winter months as thoroughly as in the warmer seasons of the year. Finally, as the water is not to be reservoired, but used for domestic purposes directly, I shall advise its filtration in order that the bacteria, which may be considered as having performed their work, shall be gotten rid of as far as practicable, on the ground of making assurance doubly sure, and on the ground of their superfluity. Tfye Aniericap Journal OF the MEDICAL SCIENCES. MONTHLY, $4.00 PER ANNUM. WITH 1892 The American Journal of the Medical Sciences enters upon its seventy- third year, still the leader of American medical magazines. In its long career it has developed to perfection the features of usefulness in its department of literature, and presents them in unrivalled attractiveness. 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