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(The statements referred to follow :)
STATEMENT OF CHARLES G. BUELTMAN, TECHNICAL DIRECTOR,
THE SOAP & DETERGENT ASSOCIATION
Honorable Chairman and members of the Special Subcommittee on Air and Water Pollution, I am Charles Bueltman, technical director of the Soap & Detergent Association, with professional training and experience as a sanitary engineer. My function is to assist members of our association in the guidance and interpretation of cooperative research programs, not only on an intramembership basis, but also on a contract-and-grant basis with universities, private aboratories, as well as independent research.
Ours is a factfinding and information-gathering effort which formally began back in 1951 with the formation of the Technical Advisory Council (1). Members of the association at that early date became aware of local problems that were beginning to appear as the result of increased usage of a surfactant material known as ABS or alkyl benzene sulfonate. Although this material was available earlier, its skyrocketing use on a millions of pounds per year basis in household detergents began to occur only in the late 1940's. The last available igures (1962) indicate that ABS is now consumed at the rate of 560 million pounds annually as its part of the 4 billion pounds per year of packaged deterzent consumed by the housewives throughout the United States (2). Exhibit 1 iisually depicts the average portion of the final packaged product represented by he surfactant or alkyl benzene sulfonate. The remaining contents of the wackage are the builders and miscellaneous ingredients that enhance the cleansng properties of the ABS or tailor it to do a specific chore-heavy-duty and/or ight-duty laundering, dishwashing and specialized commercial cleansing such is in food processing, hospital sanitation, building maintenance and many, nany other specialized cleansing functions. I will not pretend to discuss this ispect of detergent formulation in detail, inasmuch as men more technically qualified to discuss these aspects will follow me.
I would like to speak about the role ABS—alkyl benzene sulfonate—is playng as a pollutant. Let me first state that the industry has recognized the fact *hat ABS is a pollutant, and has properly assumed the responsibility for removng ABS from this position through the development of a surfactant which vill degrade at a faster rate.
The development of a product to fulfill a specific need, in this case faster viodegradation, required an understanding of the mechanisms of breakdown, · he contributing environmental factors and the influence of various methods of sewage treatment on the present ABS. Once this was established, replacenent products could be examined as to their ability to meet these requirements, s well as the primary function of being a good all-purpose cleansing agent. t must be remembered that this industry counts as its customers the more han 180 million people in our country. It has been estimated, by others, that ess than 10 percent of these people are affected by the residues of detergents n water supplies and sewage treatment plant effluents. Thus the satisfaction f the other 90 percent could not be subverted to the interests of the 10 percent, who themselves demand not only a biologically soft product, but also a product which will still maintain the high cleanliness and sanitary standards we demand n our society. I mean by this, the industry must and will produce a product o satisfy the entire 100 percent of the population. Early complaints associated rith the presence of ABS in water were primarily ones about foaming, and he presence of an offtaste and odor. We recognize that ABS will begin to Shibit transient foam properties at a concentration of 1 milligram per liter, nd that no one desires to drink water which exhibits a foaming tendency. his fact was recognized by the U.S. Public Health Service when setting forth e 1962 drinking water standards wherein it is stated: “It is recommended that kyl benzene sulfonate (ABS) in drinking water be limited to 0.5 milligram r liter inasmuch as higher concentrations may cause the water to exhibit desirable taste and foaming." However, they further state: “ABS is essenUly odorless. The odor and taste characteristics are likely to rise from the gradation products of other wastes rather than ABS * * * waters containing is are likely to be at least 10 percent of sewage origin for each milligram S per liter present.” Thus * * * "Concentrations of ABS above 0.5 milliim per liter are also indicative of questionably undesirable levels of other vage pollution” (3). And from an article by Jesse M. Cohn of the Taft
Sanitary Engineering Center which appeared in the May 1963 issue of the Journal AWWA: "ABS is always accompanied by other contaminants from domestic or industrial sources, however, and the reported taste and odor must be attributed to these contaminants" (4).
Gentlemen, this could become a very lengthy presentation if I were to attempt a full discussion on each of the areas where concern has been exhibited at ode time or another, insofar as the influence of ABS on various water and sewage treatment operations, and its effect on our water supplies is concerned. Mr. Frank M. Middleton of the U.S. Public Health Service, Taft Sanitary Engineering Center at the University of Minnesota's Ninth Annual Wastes Engineering Conference, summarized most succinctly the results of intensive investigation in this regard as follows (5):
“EFFECTS ASCRIBED TO ANIONIC SYNTHETIC DETERGENTS-ABS "1. Froth at sewage plant-ABS not the only cause, but a significant contribution,
“2. Foams in rivers-ABS not the only cause, but a significant contribution. "3. Ground water contamination-a symptom of pollution. “4. Taste and odor source in drinking water-not likely. *5. Health effects-none. “6. Esthetic effects
of principal concern. "7. Aquatic lifeconcentrations in streams well below dangerous lerels. Fish toxicity 3.5 to 6 parts per million.
“8. Coagulation and sedimentation—not significant effect. “9. Fouling ion exchanges—not significant."
In passing, as evidence that ABS is not the only cause of foam, I would call your attention to the February 14, 1963, newspaper (exhibit 2) which repmduced pictures taken in 1926 (before synthetic detergents were invented) of the Blue River at Crete, Nebr., which showed excessive foaming, due to natural causes (6). This happens in many other rivers of our country also, but I will not take the time to document this, for the industry is positively moving forward to produce products that will eliminate ABS's contribution in this regard, and those incidents of this nature due to ABS will become of historical record.
[From the Crete (Nebr.) News, Feb. 14, 1963)
"RIVER SUDS HERE BEFORE DETERGENTS"
"The most ridiculous story I ever heard,” stated Earl Krebs, longtime Crete resident.
Krebs referred to the sudsy problem the Blue River is causing in the Wilber and DeWitt areas and the blame placed on hard detergent pollution by Ma Steen, game commission director, and T. A. Filipi, secretary of Nebraska's Water Pollution Council.
Drifts of rolling suds, similar to that found in your dishpan, except that these have reached heights of 20 to 25 feet, have been dissipating on the river below Wilber this week.
Krebs stated that he has lived above the upper dam on the river in Crete since 1925 and he has seen the same phenomenon several times ". that was before detergents were even manufactured," he laughed.
Krebs said that his explanation was that when the ice melts and the water temperature is approximately 36°, the dust and other foreign matter in the melting ice will cause a foam as it rushes over a dam.
He recalled that in 1928 the suds reached heights of 28 feet in Crete, costpletely covering the dam and about 3 acres surrounding the river.
“And one year the temperature dropped suddenly while the river was foc ing," he said, “and people traveled for miles around to see the frozen soap sods"
Mrs. Joe Kalal, another Crete resident, recalled that when her husband was plant engineer on the Blue River Dam near Milford, the same thing occurred
This happened in the spring of 1926 and Mrs. Kalal remembered that it took less than 24 hours before the entire dam was covered with white foam and pieces of foam were carried as far as their home, four blocks away.
It lasted 3 to 4 days, she stated, and then gradually disappeared.
"At that time,” she said, "we talked to oldtimers in the area who remembered the same thing happening in the early 1920's. Their explanation was that the water from underground springs and the river ran so fast with the spring thaws that it took a chemical from the gr nd which caused the foam.
"I don't know if this is the correct explanation," she went on, “but at least I know that the river was known to suds before hard detergents were on the market."
According to the 1960 census of housing, 34 percent of the housing units in this country are equipped with on-lot septic tanks and wells, or in other words, a built-in closed circuit of water to waste to water. (7) Albeit relatively few of these have had problems. Our attention in this area was immediately directed to the allegations that the surfactant nature of ABS caused the soil to become *slippery," and therefore sped up the migration of harmful bacteria through he soil. Again, work done at the Taft Sanitary Engineering Center specifically nvestigating the potential enhancement or inhibition of bacterial migration hrough the soil, due to the presence of ABS, proved conclusively that ABS neither enhances nor inhibits bacterial migration. (8) Therefore, claims that vells have been made bacteriologically unsafe because of the presence of ABS n the ground waters are unfounded. This work confirmed previous theoretical alculations, that at the dilute concentrations of ABS present in our ground vaters the surface tension influence of ABS was completely dissipated.
Further, the Soap and Detergent Association and its members, at the request of State Senator Frank Van Lare, chairman of the temporary State commision on water resources planning is cooperating in New York State in honest 'ndeavor to obtain all of the facts in an intensive study of the fate of various letergent products in the septic tank-private well cycle. (9) This is an addiion to a sponsored contract the association has placed with the University of California under the direction of Prof. P. H. McGauhey to study various prodcts in a pilot plant septic tank, tile field operation. (10)
The constructive use of foam in activated sludge treatment systems is the ubject of considerable research activity by researchers. It has been found hat tertiary treatment in the form of forced foaming not only removes the BS residuals remaining after secondary sewage treatment but also removes ther refractory compounds, many of which due to lack of analytical techniques emain unidentified not only as to what they are but more significantly as to heir effects on water quality.
The problem with the use of forced foaming as a tertiary treatment technique as been the economic disposal of the foam thus produced. A member of our ssociation, California Research Corp., found that the foam may be recycled ack to the influent to the secondary treatment unit (atration basins) where ontinued exposure and reexposure to the active bacterial environment will cause 5 percent plus degradations of the ABS. Whether or not there the same imroved degradation of other refractory compounds is accomplished through this cycle technique has not yet been demonstrated. This leads me to a misconception in the minds of many people, that is the (tent of degradability, or lack of degradability of ABS, which I would like
briefly discuss. In this regard I am specifically referring to the branched sain ABS presently found in more than 75 percent of today's household detergent oducts. Field surveys of sewage treatment plants to determine the influence "ABS on treatment operations not only revealed that this influence was negative · nonexistent but also revealed that branched chain ABS is degradable. Treatment plants, receiving normal attention, will average branched chain BS reductions of 2 percent in primary treatment, 25 to 30 percent in trickling ters, and 50 to 60 percent in activated sludge.
With careful attention to an activated sludge system ABS reductions can be increased to as high as 80 percent. In fact, it was also found that increasing the mixed liquor suspended solids level in aeration basins not only improves ABS reduction but also eliminates the foaming nuisance on the aeration basins tbeoselves. (11) These findings show that dependent upon the circumstances and conditions, branched chain ABS is degradable from levels of 25 to 95 perceni. Also emphasized is the difficulty involved in attempting to establish a standard test method for determining degradability. A technical subcommittee of our association has been working intensively on the latter problem for quite soire time, with the results to date only confirming the complexity involved: the difficulty of developing a test method which will be universally applicable, not only to all surfactants but also in the ability of separate laboratories producinz repetitive results.
One last item, gentlemen, and that is the level of ABS in our water supplies and the potential that continued use on an increasing basis will cause increases in the present levels of concentration.
A survey conducted by our association of the drinking water of 32 cities throughout the country in 1959–60 (12) illustrates (exhibit 3) clearly that the levels of ABS present are certainly well below, not only the USPHS suggested maximum of 0.5 milligram per liter ABS but also well below the AWWA suggested lere of 0.2 milligram per liter ABS considered permissible by them, even in an ideal water. (13)
1 One-eighth of United States.
These low levels were confirmed by Mr. Floyd B. Taylor, of the l'SPHS, WE in he reported on 165 cities (14). This survey shows a mean arerage (dyrt.tration of 0.054 parts per million alkyl benzene sulfonate (exhibit 4). Eren mit recently the Wisconsin Detergent Study Committee reported * "studs of 1:+ surface-water samples revealed that only 5 had detergent residue concentration higher than those specified by the USPHS standards for drinking water, tliree of the five high samples were taken from a stream known to be polluted by sewage.” (15)
Thus, after more than a decade of large volume, national use of alkyl bera sulfonate in our household detergents our drinking waters reflect a wide mare". well below the esthetically based, recommended maximum of 0.5 milligranske? liter alkyl benzene sulfonate, which you will recall was set by USPHS.
As to the accumulative possibilities, the best documentation available is the long-term monitoring of the Ohio River. From this illustration (exbibit) can see that for over a decade the levels of alkyl benzene sulfonate in the e' River, well known for the fact that it receives the sewage effluents from a densit populated area, and that its waters are subject to reuse many times over. Ibe concentration of alkyl benzene sulfonate in this river certainly has Do leo subject to any accumulative effect, and in fact seems to have lereled out at : concentration of 0.16 parts per million alkyl benzene sulfonate, despite increix use of household detergents containing alkyl benzene sulfonate. (16)