Document 15EaaNBG22VRjD95JOnjN5OoE

volume number date i 4 JANUARY 11, 1980 CertainTeedEI PLAINTIFF LP-273 " I A!CPipe & Health Bulletin FROM: Roman P. Korobij SUBJECT: UNIVERSITY OF CALIFORNIA - KANAREK STUDY "Asbestos in Drinking Water and Cancer Incidence" - University of California - EPA Study This flare-up of the asbestos and health issue began when the EPA made a grant to Dr. Robert Cooper of the School of Public Health at the University of California. The purpose of this grant was to finance a study of the San Francisco Bay Area water supply to test the hypothesis that there is a positive association between the presence of chrysotile asbestos in drinking water supplies and cancer incidence in the human populations served by those water supplies. The San Francisco Bay Area was selected because it is known that there are varying degrees of asbestos content in the water supplies. The study was conducted by Marty Stevens Kanarek and was the sub ject for his thesis for a doctorate degree from the University of California. In his thesis, Kanarek reported that statistically significant results were found for cancer of the peritoneum for both sexes, lung cancer for males and gall bladder and pancreatic cancers for females. CTD032408 UNIVERSITY OF CALIFORNIA - KANAREK STUDY PAGE 2 1/11/80 Although Dr. Cooper had not issued his report, the thesis none theless was forwarded to EPA and at the direction of the EPA an abstract of the thesis was sent to utilities involved in the study. Shortly thereafter front page headlines in the San Francisco and Oakland newspapers proclaimed that the drinking of Bay Area potable water supply had been linked to cancer. Naturally, this tended to create a mini panic with lots of press and T.V. coverage paid to the news. However, public interest soon died down. The reason was in part due to the rational ap proach by the California State Public Health officials. The California Public Health Department issued a position that the University of California doctoral thesis contained no new or original evidence of a medical nature about cancer and asbestos. Nor did it establish any causatal link between asbestos in the Bay Area drinking water and the incidence of cancer. It simply requested that water utilities should develop plans to reduce the asbestos content in their water supplies and to adjust water quality if necessary so that there would be no pickup of asbestos from A/C pipe. The EPA has issued several position papers on this study. The most significant part of their position papers is the statement that the results of this new study in California are not definite enough to justify extensive modifications in water supply treatment and distribution, but it would be prudent to operate water systems to minimize fiber counts. This would include optimal operation of filtration to remove fibers from raw water when present and actions to stabilize distributed water so that it does not erode the A/C pipe and then add fiber to drinking waters. The industry's position on the Kanarek study is that although the data do support a statistical association, they are clearly inadequate even for speculation in establishing a cause and effect relationship. Determining causality involves a number of indispensable factors, none of which is considered in this study. For example, the multifactorial etiology of cancer is well known, particularly in relation to cancer of the lung, yet this factor is not adequately discussed in the Kanarek thesis. With respect to cancer of the gall bladder and pancreas, there is a complete absence of data indicating an increased risk to those cancers among those highly exposed occupationally in the past to asbestos, so any potential association in the general population would have to be examined more critically than is done in this study. In the case of cancer of the peritoneum, peritoneal involvement is a most common occurrence even though the primary site of the cancer may be CTD032409 UNIVERISTY OF CALIFORNIA - KANAREK STUDY PAGE 3 1/11/80 another organ of the abdomen; therefore, it is critical that cancers of the peritoneum be studied to determine whether they are primary or secondary tumors, Again, the Kanarek thesis does not take this factor into account. In summary, cancer causation is a highly complex process and the superficial biological observations of the Kanarek study do not support asbestos in drinking water as being causally related to the cancer incidence noted in the report. CTD032410 m.vs itn.r.nG:; Deportment of Health Services Vli* ? Street, Sucromento, CA. 95Bl4 f DUMBER: 52-70 TO?. RELEASE: IkfiCDIATE DATE: CONTACT; 22 September 1978 Pete V.'cisscr (916) 1*45-1967 The UC doctoral thesis cbstrect (entitled: Asbestos in Drinking Water end k Cancer Incidence) contains no nev or origins! evidence of a mcdiccl nature cbout cancer or osbestes, nor does it establish any causal link between esbcslos in Bey Area drinking -water end the incidence of cancer. It doer suggest cn apparent statistics! correlotl.cn between voter r.uppli c . high in naturally occuring osbentes end highcr-thcn-crpcctcd cancel of re::? hod; sites, including the stomach. The department ngrees with the student's conclusion (recited on pages 155 end 156 of the complete thesis) that: "The results of this study can only be Judged as cuggestive of needed further research into the question of the curcinogcnic effects of asbestos fibers in drinking water. "The study design was the indirect approach; census tracts were compared. Indirect epidemiological studies such ns this one can only specify associations, and cannot pinpoint causation." As the student also noted in his conclusion the sample was limited and potentially important variables such os cigarette creoking, alcohol consumption and other dietary factors were not included in tils research. Accordingly, it would be unscientific to conclude from the relatively najro-. scope of research of this study that Hay Arco voter users need to change in any wav their habitual and customary use ami consumption ol voter. However, Ih? research path explored here merit:; further study. CTD032411 52-78 2- 22 September 1978 The department plena to consult. with the voter utilities involved in the study and stands ready to perform further research and consultation vith locu 1 health officers, the university, the Federal Environmental Protection Agency, end other agencies and individuals vith an interest in safeguarding California < water supplies. .p Ve suggest that persons interest'in the water aspects of this study contact the Ecnitcry Engineering Section cf the State Department of health Services fit (^5) h'^-YJOO. Persons interested in the cr.ncer epidemiological cr.rectr of the study, which is now being reviewed by the Environmental Protection Agency, may contact Dr. Donald Austin, Chief of the Department' c Resource for Cancer Epidemiology' through the 6one telephone number in Berkeley. oOo ASSIGXMZhT EDITOR'S NOTE: The Department health Services rjeeting vith veter utility representatives is scheduled for Tuesday at 10 am at the Department of Health Services offeree at 2151 Berkeley Way in Berkeley. The meeting is scheduled for Room 123. CTD032412 Water Quality Deterioration in the Distribution System by Earl F. McEarren, Ralph W. Buelov, Robert C. Thuruau Marvin Cardels, R. Kent Sorrell, Patricia Snyder and Ronald C. Dressman For Presentation at Water Quality Technology Conference, Kansas City, Missouri December 5th and 6ch, 1977 Water Supply Research Division Municipal Environn-.encal Research Laboratory U^S. Environmental Protection Agency Cincinnati, Ohio 4516S CTD032413 7 Wacer Quaiicy Deterioration in che Distribution System Inti educ tion Everyone in the uacor industry probably is aware that lead plumbing was used in ancient Rome and has read or heard speculations concerning the possible relationship between the use of lead pipe and the downfall of Rome. Because of che high toxicity of lead, other materials like copper and galvanized icon have largely replaced lead as discribucion piping macerial during che last one hundred years. However, many older syscems, like Boston, Massachusetts and Benningcon, Vermont scill concain lead service lines chat were installed many years ago. Not only mecals, but also organic materials and particulates may be released from che discribucion syscem when piping materials such as polyvinyl chloride, asbestos-cement, or coal tar lined pipes are used. These compounds also have health significance. In the case of metal and asbestos-cement piping Che release of subscances from the piping materials is the result of corrosion, depending mostly upon the quality of che water. Important water quaiicy parameters relaced co corrosion, are pH, alkalinity, hardness, cemperacure, dissolved oxygen and dissolved carbon dioxide. In the case of coal-car-lined or plastic pipe, che quaiicy of the wacer is of minor importance, and che concern becomes simply a matter of leaching of material from the pipe or lining by che uacer. CTD032414 2 this report will acter.pt not only to presenc some daca to tlluscrace it the nature or extent of the problem encountered with each kind of pipe buc will also discuss methods for the concrol and measurement of each parameter. Oecerioracion of wacer quality in metal pipes will be discussed first, followed by asbescos-cement pipe, Chen plastic pipe and finally coated pipes. Galvanised Iron Pipe Loop A galvanized iron pipe loop study was initiated because of a continuing quescion as co whether cadmium (an impurity) was leaching from the zinc coacing of galvanized pipe and chereby getting into domestic water supplies. A pipe loop was fabricated from 1/2-inch pipe, and connected co a system of pumps and timers that simulated household usage (see Figure 1). Based on the analysis of che galvanized pipe coacing, concentrations of 0.054 ug/t of cadmium and 9.1 ug/1 of lead were calculated to be expected if the pipe was exposed to corrosive wacer. To check chis conclusion and to simulate the worst possible condition, deionized water was circulated through 160 ft. of pipe at the race-of 200 gallons per day, with intermittent flow to simulate household.usage, and only samples of the wacer thac had been standing in che pipe overnight were collected for chemical analysis. Afcer four weeks of operation, analysis of che data showed thac the lead concentration in the water varied from 3.2 co 24.1 ugit and the cadmium from < 0.04 to 0.2 ug/i. 2inc, as expected, uas the only metal found in quantity; namely, 230 to 1400 yg/2. From chis experiment cadmium impurities in galvanized pipe was concluded not Co be a problem, buc that lead night be. Lead In Distributed Water Distribution studies conducted several years ago In Seattle^ and 2 3oston illustrate the effect of corrosive water on cap-wacer quality. CTD032415 -3- FIGURE 1. SCHEMATIC OF GALVINIZED PIPE LOOP. RECIRCULATION CTD032416 -u - Boch Bcsccn and Seaccla use impounded surface uacer and provide chlorination as che only creacmenc. Seaccle also fluoridates. The hardness and alkalinity of chese waters are low, and the pH is on the acid side. In Seattle thac part of che distribution system served by the Tolc River was sampled. Samples uere collected from 31 points in che discribucion syscem, primarily household caps. Two types of samples were collected early in che morning for comparison - a scanding and a running sample. Scanding samples uere che first to run out of che faucec in che morning, representing water with a long residence cime in che household plumbing and service line. Running samples-uere collected afterward, ensuring chat the house lines were well flushed and represented water froa the mains. This same procedure was followed in Boston, and running and standing samples uere collected at 54 households in the Beacon Hill area. The difference in mecal pickup becveen these systems (see Table I) is mosc likely related to the type of plumbing material and service lines in use. In Boston a high percentage of homes sampled had lead service pipes; in Seattle copper and galvanized iron were more commonly used, h'o lead pipes were reported in Seattle and the source of the lead was assumed to be from the solder used to join the copper piping.^ In light of the galvanized loop studies reported above, the source of the lead more probably was the galvanized pipe because all the houses but one had galvanized iron pipe plumbing, although a number (about half) did have copper service lines. Recently, In a class action suit brought by a private individual against ERA, che distributed water of Benningcon, Vermont also uas shown to contain high levels of lead (See Table II). In chi3 CTD032417 Table I. Boston and SeaccLe Wacer Quality Parameters Parameter pH Hardness - mg/2 Alkalinity - mg/2 Chlorides - mg/i Sulfaces - mg/i Lead** - running - mg/1 scanding - mg/2 Boston 6.7 14.0 8 12 10* 0.241 0.321 ~4eactle 5.5 6*0 2 2.1 2 0.022 0.170 * 0.008 correction for lead determination required ** maximum values case, the interior results Indicate the first water collected from the household plumbing in the morning, the service results represent the water sample collected after allowing the water to run until it became cool, and the main results are the water samples collected after allowing the water to run for an additional one or two mi**ces. A lead pipe loop has also been constructed by the Water Supply Research Division. Our experimental apparatus- consists of 100 ft of 3/4 inch diameter lead pipe, a 350 gallon reservoir and a series of pumps and timers. The reservoir allows the chemistry of the wacer encering the loop to be closely controlled and permits several days operation from a single batch of water. In thl3 case, the wacer from the loop goes to waste rather chan returning to Che reservoir. The pumps and timers simulate daily usage uich 100 gallons being selecced as che daily volume. The firsc series of tescs were designed to sinulacc the effect of Boston CTD032418 -6 - Table II. Lead" in Bennington, Vc. Water Samples Residence Water from Interior plumbing Wacer from Service Line Water from Screec Main A .165 .440 .096 B .112 .096 .047 C .155 .180 .110 C .124 .144 .056 .165 .540 .072 F .145 .448 .200 C .150 .132 .450 H .185 .860 .156 I ' .328 .600 .592 . J .165 .460 .145 . Raw Wacer - pH 5.5, ailkalinicy 1.0 , sodium 0.7, lead < . 005 * all values in mg/1. water upon new lead pipe and to observe Che effect of increasing the pK (A possible control procedure) of Che water upon the lead concencracion. A simulated Boston water was achieved by mixing Cincinnati tap vacer with deionized water in a ratio of 1 to 10, the pH being adjusted with sodium hydroxide. The lead data that are reported (Table III) were obcained by analysis of wacer that had resided in the pipe overnight and is assumed to be the worse condition. Adjustment of the pH was not expected co significantly louer the lead values and the data shows chat adjustment of che pH did not (see Table III). Ac present, it is not understood why the pH of the water in the pipe (see Table III) Increased. The next cest will be co observe CTD032419 Table III. Lead Concentration as a Function of pH Tesc Humber PH Mo. of Days Incended Reservoir Loop Avg. Lead Cone., mg/2 Langelier Index Reservoir Pipe 18 7.5 7.6 9.61 0.167 -2.11 -0.16 2 9 8.5 7.9 9.24 0.169 -1.39 -0.49 3 6 9.5 9.1 9.60 0.137 + 0.54 -0.13 Alkalinicy 10.2 co 11. 3 Hardness 18.1 to 21.1 the effect of che addicion of sodium bicarbonate co increase che alkalinity upon che lead levels. The Church and Dwight Co., Inc.^ sug gesc that wich such treatment che lead levels can be reduced to as low as 0.016 mg/i- The Virginia Chemical Co. also suggests that the addition of zinc orcho phosphate with the pH controlled to between 7.0 to 7.3 should be effective. Supposedly the zinc phosphate (which has a lower soLubility . than either calcium or zinc carbonate) causes a film to be formed on the pipe which protects the pipe and prevents corrosion. This possibility will be investigated later. In analysis of che samples for lead, the so-called "flauieless acomic adsorption spectrophotomecric" or graphite furnace technique was used. Vich this technique, however, caution does need co be observed because sulfate^ in che water sample will suppress the signal and produce erroneous results. One can either add lanthanum Co Che sample and standards co overcome this effect or measure the concentration of sulface in the water and apply a correction co che lead results. The Boston lead values cited above have been corrected in the latcer manner by adding a CTD032420 faccor of 0.008 mg/1 co the lead results to compensate for the presence of 10 mg per liter of sulfate. Asbescos Cement Pipe The AUVA Scandard C4QQ-77 establishes criteria for determining the qualicy of wacer that can be transported through A/C pipe without any adverse effects. These criteria are: (a) Use either Type I or Type IIpipe where pH + log (AH)2 12 (b) Use Type II where pH + log(AH) 10 Where: Type II A/C pipe is autoclaved and Type I (no longer manufactured in chis councry) is noc. pH " index of acidity or alkalinity of the water in scandard pH units A =* the total alkalinity in mg/i as CaCO^ H * the calcium hardness in mg/1 as CaCO^. because (according co the above) pH, alkalinity and calcium hardness of the wacer are the main factors that determine vhecher water is aggressive or corrosive co A/C pipe, a range of wacer qualities from che aggressive to the non-aggressive were selecced for field evaluation. Six public uacer supply systems chat used A/C pipe and whose water had combinations of pH, alkalinity, and calcium hardness co produce aggressive indices (A.I. from the equation above) ranging from 5.34 to 12.85 were finally selecced for a year long scudy. Water samples were collected by the local water utility or water supply regulator personnel on che average of at lease once every two monchs. The samples were collected in 1 qc (946 mi) cubltainers and shipped to EPA Wacer Supply Research Laboratory, Cincinnati, Ohio for analyses. To determine che possible release CTD032421 / -$ - \ asbescos fibers from che pipe walls, samples of wacer as ic encored ticrosaopt. Samples roc asoesccs analysis were preserver wru. r.: rouriw chloride, uhile ocher samples collecced ac che same cirae and place for pH, alkalinicy and calcium hardnes were non-preserved. Table V Uses che six syscems scudied, cheir uacer qualicy characceriscics and chelr asbesco3 fiber counts. As can be seen, consiscencly quancifiable fiber councs were found only in che cuo syscems wich very aggressive wacers. Table V. Wacer Qualicy Paramecers Same of Syscem pH Alkalinicy Calcium Aggressiveness mg/i CaCO^ Hardness Index mg/i CaCOj (A.I.)* Avg. Chrysocile Fiber Counc Fibers/licer Pensacola, Fla. 5.2 c King Councy Wacer Disc. No. 58 Seaccle, Wash. 7.2 Crane Hill Assoc Bloomfield, Conn .' 7.5 Clark Councy Ucilicics, Norchridge, OK 7.3 Lockharc, Texas 9.4 Cleburne, Texas 9.7 1.0 14 88 22Q 50 36 1.4 14.5 82 250 44 39 5.34 9.51 11.56 12.54 12.74 12.85 5.52 X 106 0.66 X 106 NSS BDL BDL BDL *As uacer encered pipe NSS - noc scaciscically significant BDL - Below che Dececcion Limic c CTD032422 10 For asbestos analysis, from 100 Co 500 mi (depending upon the amounc of ocher debris present) of a well mixed sample was filtered with suction chrough a 0.45 urn pore diamecer millipore filter. The filter was removed, dried in an oven at 45C for 2 hours, a 3 mm circle cut ouc of che filter and placed upside down on a carbon-coated (200 mesh) copper grid, lhe grid is then placed on che coldfinger of a side arm condenser washer chac has been charged vich acecone. The acecone is Chen refluxed for four hours to dissolve away che filter and leave the residue deposited on che carbon-coated grid. The grid was then placed in a transmission electron microscope mounted in a special carbon specimen holder and viewed at 17,000 X. Ac least 10 grid holes on each of cvo grids were viewed. Every time a fiber was found, an electron diffraction pattern was attempted. A fiber vas then counted, provided a diffraction pattern was obtained which was characteristic of either chrysotile or one of the amphiboles. If any doubc exisced concerning che identity of a fiber an energy dispersive xray spectrum was also obcained. The mlcroscopist used a tally sheet to note che number of fibers found in each grid hole and to note che size of each. When 20 grid holes had been counced, an average of che number of fibers found per hole was calculated, and this used to calculate che number of fibers per liter of sample. This procedure is che same as chac presented at an earlier meeting of chis association in Dallas and is published in Che proceedings I of chat meeting.^ It is also, for all practical purposes, identical to Q an "Interim Mechod for Asbestos Analysis" recently adopced by EPA. Although not indicated in Table V, che pH, alkalinicy, and calcium hardness increased as the wacer passed through Che pipe, presumably as a result of the water reacting vich che cement in che pipe, and thus causing the water to become less aggressive co che pipe. CTD032423 u- This is evidenc also from Sell (scanning electron micrographs) of an inside section of unused a/c pipe (Figure 2A) and a piece of the incerior surface (Figure 2B) of the pipe from the King Councy Water Districc. As can be seen in Figure 2B, the incerior surface af che pipe is significantly changed. Although no known or proven methods for controlling corrosion of A/C pipe exist, che above observations would indicate that simply adjusting che pH upward and adding calcium might solve che problem. This seems, however, too obvious and some people might object to an increase in the hardness of their water. Currently, two ocher procedures chac have proven successful with cast iron pipe are being tested'. The Wacer Supply Research Division has a reserach a grant with Greenwood, South Carolina to try pH adjustment and coating of the pipe with zinc ortho phosphate and also has a research contract with the Corner Uacer Company in ShippenviLle, Pennsylvania for rehabilitation of their badly deteriorated asbescos-cemervt pipe by cleaning of the pipe and then coating it in place by using controlled calcice-cemenc deposition (McCauley Process). 9 ' 10 Polyvinyl Chloride Pipe Studies Polyvinyl chloride (PVC) pipe has been in use to varying degrees in some wacer distribution systems in che United States for the pasc 18 years. Recencly, however, concern has been raised chac unpolymerized vinyl chloride remaining in the pipe could migrate into the wacer flowing through it. To investigate chis theory existing methodology^ for vinyl chloride was improved L2 to permic the detection and measurement of vinyl chloride at very low concentrations in wacer, and five wacer systems chac used PVC pipe were studied. In a paper submitted to Che Journal of the American Uacer Uorks Association in May 1976 concentrations beeween 0.01 and 1.4 yg of vinyl chloride per liter of wacer were reported*^ in the distributed water, although none was found In the source. The lesser concentration was found Co perslsc in a syscem containing pipe CTD032424 13 chat was nine years old and the higher concentration was tou4 in rt* newest system (pipe about 1 year old). These levels are well below those chac have been associated with adverse effects In experlnehteS. animals, and should decline as lower residual monomer pipe (the only known means of control) is puc into use. To achieve greater sensitivity chan can be provided by purging a 5 mi sample,^ a modification was developed to enable the contents of a 40 mi bottle to be purged onto a silica gel trap. 12 The vinyl chloride is then desorbed onto a column composed of one third Chroraosorb 101, and two-thirds Chromosorb 102, rather than all Chronosorb 101 in order to resolve vinyl chloride and cyanogen chloride, an interference in some samples. The gas chromatograph is initially set at 50C, but is programmed to rise by 10C per minute co. 160C. Microgen carrier gas flow uas 80 mi per min. and desorb (inlet) cemperature was 150C. Detection was achieved by using the halogen, specific aicrocoulomecric decector, and Che limic of detection was 0.1 pg/l. Asphalt Coated Pipes To prevent corrosion of cast iron or steel pipes and1co aid in the. curing of cemenc lined pipes, the innerside of such pipes may be lined " wich asphalt or coal-tar coatings. Depending upon conditions, cemperature, thickness and age, during che production of these coatings, polynuclear aronacic hydrocarbons (PAH's) may be released. The solubilicy of most PAH's in water is relatively low; however, a number of representatives of che PAH's are known carcinogens and che World Health Organization has recommended a limit of 200 ng/t for che total of six representative P.A.H.'s (a value well belou cheir solubility). Table VI lists some of che PAH's thac have been found In water, 14 and Indicates their relative carcinogenic!cy. CTD032425 - u TABLE '.'I SOME PAH'S FOUND IN WATER NAME 8ENZO lal ANTHRACENE BENZO |ta) FLUORANTHENE BENZO |j) FLUORANTHENE BENZO (a) PYRENE BENZO |e) PYRENE CHRYSENE 1NOENO (1.2.3 cd) PYRENE ANTHRACENE PENANTHRENE BENZO ('*) FLUORANTHENE BENZO (gni) PERYLENE FLUORANTHENE STRUCTURE ca? aS CARCINOGENICITY +* 2co 8> <3?= cffio coo a? ca2) & * 7 7. - PERYLENE PYRENE 1-METHYL PHENANTHRENE 2-METHYL PHENANTHRENE 1-METHYL PYRENE CORONENE strong * MOOERATE WEAK - INACTIVE 7 UNKNOWN 8 c^"3 a?*"3 cg)CH3 7 7 7 7 CTD032426 15 A high pressure liquid chromatographic procedure (K?LC) for the determination of PAli's^' ^ in distributed water is presently under development. Because the details of this procedure will be discussed at another session of this meeting, (see paper by Sorrell, K., McFarren, E.F., and Dressman, R. , High Pressure Liquid Chromatography for Measurement of Polynuclear Aromatic Hydrocaroons in Distributed Waters, in the proceedings of the meeting), chey will not be discussed here. The next step will be to select various cities around the United States where there are asphalt lined pipes in place, and attempt to deceraine whether during passage of water through the system any increase in PAH concenc occurs. If any PAH's are found, an attempt will be made to correlate Che PAH content of the water to the age and length of pipe, and the type of coating (bituminous or petroleum base), etc. No methods for the control or for the prevention of PAH's geccing into che wacer are known or have been investigated. Summary An attempt has been made to identify che problems that may be encountered uhen different kinds of pipe (galvanized, lead, poly vinyl chloride, asbestos-cement, and asphalt coated) are used to distribute uacers of various qualicy. The methods of analysis developed to idencify these problems as well as ideas for controlling or preventing che deterioration of che wacar qualicy during distribution are discussed. CTD032427 EXPOSURE TO ASBESTOS FIBERS IN WATER DISTRIBUTION SYSTEMS Gunther F. Craun1 James R. Millette1 Richard S. Woodhull2 Richard Lauippa2 Pre-Publication Copy Presented at the 97th AlvWA Conference American Water Works Association Anaheim, Callfcrrffl* May 8 - 13, 1977 1. Health Effects Research Laboratory, U.S. Environmental Protection Agency, Cincinnati, Ohio 4S263 2. Water-Supplies Section, Environmental Health Sciences Division, Connecticut State department of Health, Hartford, Connecticut .UflMb CTD032428 EXPOSURE TO ASBESTOS FIBERS If: WATER DISTRIBUTION SYSTEMS Gunther F. Craun and James R. Millette Health Effects Research Laboratory U. S. Environmental Protection Agency Cincinnati, Ohio 45268 Richard S. Woodhull and Richard Lauippa Environmental Health Sciences Division Connecticut State Department of Health Hartford, Connecticut 06115 Serious health hazards can exist if asbestos fibers are inhaled. Asbestos-related lung cancer, mesothelioma, and fibrotic pulmonary disease have been documented in occupationally exposed populations (1-4). Ingesting such material may also be dangerous, as indicated by increased rates of gastrointestinal cancer among some asbestos worker groups (5,6,7). Animal studies in which asbestos fibers have been injected or implanted (8,9,10) indicate that the fibers may penetrate the mucosa of the stomach and intes tine. Although there is no proof that drinking water containing asbestos will cause cancer, the long term health effects of ingesting asbestos fibers are uncertain. Several surveys of domestic water supplies have noted the presence of asbestos fibers in drinking water (11,12,13). Contamination of surface water occurs because of industrial activity or from the erosion and weathering of fiber bearing rocks. Asbestos fibers can also be found in wells where the ground water originates in serpentine rock. Asbestos-cement pipe used as water mains may also contribute fibers to the drinking water if the asbestos is leached from the interior walls of the pipe. Samples collected from 64 water systems in the U.S. prior to distribution through water mains showed 29 of the systems with asbestos fiber concentrations above 50,000 fibers per liter. Systems in San Francisco, Seattle and Duluth had concentrations over 1 million fibers per liter (14). The chrysotile fibers found in the surface water sources used by Seattle and San Francisco were attri buted to erosion of asbestos-bearing rock-in the water shed. Duluth also uses surface water, Lake Superior, and the source of amnhibolc asbostiform fiber? here has been related to industrial contamination. Considerable amounts of asbestoscement pipe convey potable water in Morth America, Europe and other parts of the world. According to a recent survey by the Asbestos-Cement Pipe Industry, of U. S. cities with a population of 1,000 or more, 3 3 (6S million people) specify, purchase or have in service A/C pipe. Over 200,000 miles of 1 CTD032429 A/C pipe are now in use in the U.S. (15). Chrysotile comprises 80% or more of the asbestos used in asbestoscement pipe manufactured in the U.S. (16). These facts have raised- a q u e srf*HT*with respect to the possible health hazard that m*pbe associated with drinking water which has flowed through this type of pipe. In 1974, a committee on asbestos in water chaired by George M. Wright, M.D. prepared a report for the American Water Works Association (16) which summarized the information available on asbestos in water from A/C pipe and recommended several study areas where research was needed to answer the health questions raised by the use of such pipe. Included in the research suggestions were: a. the need for data on fiber quantities and sizes as found in A/C pipe water systems. b. the need to conduct epidemiology studies of hu man population groups exposed to asbestos-cement distri bution systems. An investigation of the use of asbestos-cement pipe for public water supplies and the incidence of gastroin testinal cancer in Connecticut was initiated in 1974 by the Health Effects Research Laboratory (HERL) in response to these needs. A multidisciplinary team of water supply officials, public health engineers, epide miologists, scientists, and statistians from 11ERL, The Connecticut Tumor Registry, and the Center for Disease Control collaborated in the design, field work, and analysis of data in this study. This report is primarily to define the methodology used to determine the extent of exposure of Connecticut's population to A/C pipe and to serve as a progress report of the initial findings of the epidemiologic study which will be described in detail elsewhere (17), Selected water samples collected in con junction with this study were analyzed by electron mi croscopy techniques (IS). These provided some data as to fiber quantities and sizes as found in a number of different water distribution systems containing A/C pipe. The size of asbestos fibers leached from the interior of asbestos-cement pipe may differ from those found in source waters . The State of Connecticut was chosen as the site of the study because of the reliable cancer incidence data over a 38 year period a vail able through the Connecticut Tumor Registry. Registration of cases during life now exceeds 98% and histological confirmation approaches 100% (19). Preliminary surveys of the use of A/C pipe in Connecticut showed that some A/C pipe had been in use for a nu in her of year? but that a major effort would have to he undertaken to document this usage by town so it would be compatible with the tumor registry data which is recorded by township. 2 CTD032430 The Connecticut Study Public water supplies, available in 148 of Connec ticut's. 169 towns, provided water to 821; of the state's population in 197S. The total population served by public water supplies in each town varied from 10% or less in 36 towns to 9S% or more in 30 towns. Because asbestos-cement pipe is unlikely to be used in indivi dual water systems, only public water supplies were included in this study. A list of public water supplies using asbestoscement pipe was compiled after surveying each public water supply and cross referencing the data with infor mation available from the Public Utilities Commission and the Water Supplies Section, State Department of Health. Public water supplies are not developed accord ing to town boundaries. Some towns are served by sev eral different water supplies and a single water supply may serve areas in several towns. Because the Tumor Registry collects data on a town basis, it was neces sary to compile the asbestos-cement pipe data in a similar manner. Each public water supply using asbes tos-cement pipe was then contacted in order to docu ment the location of the pipe and collect the follow ing data felt to be of epidemiologic importance: (a) date(s) of installation of the asbestos-cement pipe, (b) length of asbestos-cement pipe compared to other types of pipe, and (c) population served by asbestoscement pipe compared to other types of pipe. The data were then grouped by town. Asbestos-cement pipe is used totally or partial ly by 149 public water supplies in 82 towns. Approxi mately 576,800 people in Connecticut received water which has passed through asbestos-cement pipe. This compares to a total population of 1,724,000 for the 82 towns in which 1,438,500 people are served by public water supplies. In assessing the exposure to asbestos fibers from the pipe, several factors were considered. Factor: Age of Pipe Some public water supplies reported asbestoscement pipe that was 45 years old in 1975; some report ed newly installed pipe less than 5 years old. The majority (66%) of the population receiving water through asbestos-cement pipe used pipe at least 25 years old in 1975. The majority of the towns had asbestos - cement pipe that was at least 25 years old in 1975: (a) 34* had asbcstos-ccmcnt pipe 50 years old or greater, (b) 16.; 25-29 years old, (c) 16%; 20-24 years old, (d) 2 2%; 15-10 years old and (e) 12%; less than 15 years old. In a few instances asbestos-cement pipe had been used for a period of time but replaced in recent years. These were included as asbestos-cement pipe systems only for their period of usage. it. 3 CTD032431 Factor: Length of Pipe Approximately 900 miles (1450 KM) of asbestoscement pipe were found to be in use in Connecticut. The majority of the towns had at least 3 miles (4.8 KM) of A/C pipe in their distribution lines: 28% had between " 10 (16 KM) and 101 (160 KM) miles of A/C pipe, (b) 46% had between 1 (1.6 KM) and 10 (16 KM) miles, and (c) the remaining 26% had less than 1 mile (1.6 KM) A/C pipe. Factor: Population Served by A/C Pipe The percentage of the town population that received water which had flowed through A/C piper-was determined after investigating the distribution systems of each of the 149 water utilities. If the utility had a section of A/C pipe at the beginning of the distribution line, the entire population served by that utility was consid ered as being served by A/C pipe. In towns served by more than one utility the populations served by A/C pipe in each utility were added. Where a utility served two towns, the distribution system was divided according to town boundaries. Factor: Aggressiveness of Transported Water The quality of the water transported by the pipe is known to be a critical parameter in the release of fibers from the pipe. In 1973 Webster (20) presented pictures of the A/C pipe which had been carrying brine (water with a high saturation index) for a number of years. The pictures showed a well marked deposition of calcium salts lining the inside of the pipe which would protect the pipe from corrosion. He also presented pic tures of the A/C pipe that had been subjected to acid conditions while carrying sewage. These had very rough inner surfaces which presumably could release fibers through erosion. The corrosive effects of certain waters on A/C ,p^pe have been studied closely by the Asbestos Cement Pipe Industry and 3 definition of aggressive water derived from the Langlier Index is given in the AWh'A Standards C400-75 for A/C transmission and pressure pipe (21). The aggressiveness of wateT transported through a pipe, with in the temperature range of 40-80F, is determined by .he formula: aggressiveness index (A.I.) = pH + log (A x H) where: pH = index of acidity or alkalinity of the water in standard pll units A = total alkalinity in mg/l as CaCO^ II = calcium hardness in mg/1 as CaCO. 4 CTD032432 Higher values of this aggressiveness index are jless cor rosive than lower values. Ivaters with an A.I. less than 10 arc considered very aggressive while A.i.'s greater than 12 are considered essentially non-aggressive. The criteria established by AWWA Standard C400-7S are: (a) use either Type I (not autoclaved) or Type II (autoclaved) pipe where A.I. > 12.0 (b) use Type II where A.I. > 10.0 The correllation between fiber release and wateT aggres siveness has been confirmed by studies recently comple ted by the EPA (Municipal Environmental Research Labora tory) on asbestos-cement pipe distribution systems in the field (22). These investigations showed that fibers were present in water sampled over a year period from two systems which had source A.i.'s under 10.0, but few, if any, fibers ewuld be found in water samples from 3 systems with source A.I. > 12.0. In the 1974 AWWA Asbes tos in Water Committee Report (16), analyses of two sim ilar A/C pipe distribution systems were reported in terras of asbestos fiber mass/unit volume of water. The data showed that a greater amount of asbestos (0.28 ug/1) was found to be coming from the pipe in the Malvern system which had a source A.I. of 11.2 than from the A/C pipe in the Glendale system with a source A.I. of 11.8. Glen dale A/C pipe was found to have contributed 0.015 yg/1. Water samples were collected from each public water supply in Connecticut with asbestos-cement pipe, analyzed for the appropriate chemical parameters, and an A.I. was calculated for each supply. A population weighted A.I. was calculated for each town according to the number of public water supplies with asbestos-coment pipe in the town. The majority of towns had an aggressiveness index under 9.8: (a) 56% had A.i.'s under 10.0, (b) 43% had A.i.'s between 10.0 and 12.0, (c) 1 town (1%) had an A.I. above 12.0. FACTORS COMBINED FOR ASSESSMENT OF EXPOSURE: While current exposure to asbestos fibers leached from A/C pipe could best be described by direct measure ment of the fibers in the distribution system, this might not provide an accurate assessment of exposure to fibers over the entire time the pipe was used. An assessment of exposure value or risk factor was developed from the fac tors described in the proceeding paragraphs which were felt to be of epidemiologic importance and important in the release of fibers from the interior of the A/C pipe. To prevent a possible bias in data analysis, the assess ment of exposure (AOE) values were developed independ ently of'the tumor registry data. None of those calcula ting the AOE1s had knowledge of cancer incidence by town within Connecticut and thus were not influenced in the selection of parameters used to calculate the exposure to asbestos-cement pipe in each town. 5 CTD032433 A list of towns was prepared according to the per cent of population served by public water supplies a*4 towns were subdivided into those with and those without asbestos-cement pipe. The towns were further subdivided according to urban and non-urban criteria, an urban town being defined as having an estimated 197S population of > 2500 and > 50% of the town's population served by pub lic water supplies. The towns were than ranked according to the following parameters to show a relative risk of exposure to asbestos from asbestos-cement pipe. (1) maximum age of asbestos-cement pipe (2) population-weighted A.I. C3) Assessment of Exposure (AOE) as defined by: AOE * CL) X (P) x Cjg) x A.I. Factor where: L = length of asbestos-cement pipe in m41e* P = population served by asbestos-cement pipe Z = age of pipe in years A.I. Factor: use 1.0 if A.I. = *12.0; 1.3 if A.I. = 11.1-12.0; 1.6 if A.I. = 10.1-11.0; 2.0 if A.I. = >10.0. (4) Risk Factor (RF) as defined by RE = AOE/(P) The AOE and RF were developed to combine epidemiologically important parameters and factors influencing the release of fibers-from pipes. Since risk was felt to be independ ent of the population using asbestos-cement pipe, the RF was calculated omitting this parameter. However, rank correlations calculated for towns ranked by AQE arrt RF showed the town ranks to be similar (Spearman .SR#', $< .0001; Kendall .713, p<.0001) and only the AOE was used in further analysis. Since age of pipe and corrosiveness of water (A.I.) were felt to be most important in asses sing total fiber release from -pipes, these parameters were to be analyzed separately with Tumor Registry Data. To determine current exposure to asbestos in drink ing water and confirm the importance of the aggressiveness index and the other factors used to establish the relative exposure to asbestos by the towns, a study of asbestos in source water and tapwater samples from each township has been undertaken using electron microscopy techniques (13,18). Electron diffraction and energy dispersive x-ray analysis are being used to classify fibers as chrysotile, amphibole, or nonasbestos. Information on the length, diameter, and age of A/C pipe between the source and sam pling point and the aggressiveness indexes of the water at both sites are also being recorded. ---w. To evaluate if populations not served by asbestoscement pipe were exposed to naturally occurring asbestos in water sources, thirty-one samples were collected at water sources prior to entering the distribution system. 6 CTD032434 Sampling sites were selected based on the type of water source, size of system and geographic location. All major water supplies were sampLed including the Metropol itan District Commission, Now Haven Water Company, and Bridgeport Hydraulic Company. All samples except three-, were either below detectable limits, which means no chrysotile or amphibole asbestos fibers were found, or not statistically significantly, which .means that less than five asbestos fibers were found in the portion of the sample examined. The three source water samples contain ing asbestos were: (1) A drilled rock well serving 100 customers contained 100,000 chrysotile fibers per liter. (2) A surface water source serving 3,000 customers con tained 500,000 chrysotile fibers p?r liter. Resam pling is now in progress. (3) A gravel well was found to contain 300,000 chryso tile fibers per liter but this could not be confirm ed upon resampling. RESULTS Based on these sampling results it was concluded that the population served by public water systems not using asbestos-cement pipe were not exposed to signifi cant amounts of naturally occurring asbestos in water. Thus far, 19 water samples have been analyzed from the distribution system after water 4fad passed through various lengths of asbestos-cement pipe. Chrysotile fi ber counts ranged from below detectable limits (10,000 fibers/1iter) to 700,000 fibers per liter. Some amphiboles were detected; concentrations were below 50,000 F/t. Seven of the samples had chrysotile fiber counts over 100,000 fibers per liter. In general, the fiber counts were low when compared to counts reported for water in some other situations. In Duluth where the source of amphibole fibers in the water is considered to be related to mineral processing operations, fiber counts as high as 600 million fibers per liter have been found (23). Two hundred million chrysotile fibers per liter were found in water from a lake in Marin County, California which receives runoff from areas of serpen tine rock (2<l) . In some non - Cornice t i cu t asbestos-cement pipe systems which transport highly aggressive water, chrysotile fiber counts as high as 32 million fibers per liter have been found (22). f In the Connecticut samples where chrysotile fibers were found, their lengths ranged from 0.2 to 60 um with widths from 0.02 - 0.5 urn. Aspect ratios (length/width) ranged from 3 to 2000. Figure 1 presents a comparison between the fiber lengths found in the Conn. A/C pipe 7 CTD032435 distribution systems and fibers found in-a sample from a San Francisco Reservoir in California which has a natu ral source of chrysotile fiber from surrounding rock formations. It is apparent that the pipe distribution samples have a higher percentage of fibers over 1 urn in length than does the sample with a natural source of fibers. The median value of the San Francisco fiber length range was 0.7 um while the median value of the fiber length range from the Conn. A/C pipe distribution samples was 2,0 um. The data is also compared with araphibole fiber lengths as found in Duluth, Minnesota'tap water 1975 C23) l The age adjusted sex specific incidence data for stomach, colon, and rectum cancer for Connecticut town ships for the period 1935 to 1973 was used to investigate whether asbestos cement pipe usage in public water sys tems could be associated with gastrointestinal cancer. Observed versus expected ratios for the occurrence of each cancer, by sex, time period, and estimated exposure to asbestos cement pipe were calculated within each of three categories of population density. In addition, townships within each of the three categories of popula tion density were ranked for age-adjusted rates of each cancer site, by sex and time period and compared to townships ranked for exposure to asbestos-cement pipe. These correlations revealed no obvious trends or patterns of association with the use of asbestos-cement pipe (17). These negative findings seem to indicate that the use of A/C pipe has probably not been responsible for excess gastrointestinal cancers, but there arc inherent un cc r t a in i t i e s associated' with epidcmiologi.c studies of this type. Prior migration, occupational history, and personal habits regarding other asbestos exposure and smoking could not be obtained in this typo of study. Because, the study area was selected to take advantage of reliable cancer data available in the long standing State Tumor Registry, another limitation which could not be avoided was the small population served by A/C pipe. An additional factor which may be important is the rela tively low dose asbestos exposure found after sampling a limited number of water systems using A/C pipe. It seems justified, however, to report these ini tial, negative findings to allay fears that a large, obvious epidemic of gastrointestinal cancer attributable to the use of A/C pipe has been overlooked. It is accu rate to stare that if asbestos in water has ir. fluended gastrointestinal cancer rates in Connecticut, the ef fects are not obvious (17). Additional studies are now in progress to provide more substantial data on fibers in Connecticut water supplies. When the present work is completed, all S2 towns identified as using asbcstos-ccmcnt pipes will have been sampled. Supplies in thirty towns not using 8 CTD032436 A/C pipe will also have been sampled. All the major sources in each town are to be analyzed for natural asbestos content. Analysis of data from at least 82 pairs of samples, before A/C pipe and from the distri bution system after a known length of A/C pipe, will be compared with aggressiveness index changes of the water in the system. It is possible that a re-evaluation of our exposure assessment will be necessary if fiber counts do not con firm the Assessment o^f Exposure equation as a reliable predictor of fiber exposure. Closed loop studies and field sampling are currently underway to determine if one of the three parameters used to determine the aggressiveness index (A.I.) is more important than the others. Data on corrosion control practices, such as, the addition of polyphosphates is being collected to determine their influence on preventing fibers from being released from the pipe. A situation in which iron in the water can apparently coat the interior of the pipe pre venting fiber release is also being investigated. Fur ther studies will be conducted investigating the rela tionship between incidence of gastrointestinal cancer and the following: 1) current asbestos counts, 2) town ag gressiveness indexes, 3) age of pipe data, 4) revised AOE calculations, if indicated by the current sampling program. An investigation of pleural and peritoneal mesothe lioma using data from the Connecticut Tumor Registry is currently being conducted in conjunction with the Con necticut Cancer Epidemiology Program, Yale University School of Medicine. If sufficient numbers of cases of peritoneal mesothelioma are found which are not associ ated with occupational exposure, a case-control study will be conducted to determine if these are related to drinking water that has passed through asbestos-cement pipe. The Health Effects Research Laboratory is currently sponsoring another epidemiologic study in an area of California where chrysotile asbestos occurs in the source water. This study will look at cancer incidence in coun ties which maintain tumor registries. Although the fiber concentrations and sizes may be somewhat different than those found in the Connecticut A/C pipe systems, the California study will provide additional data as to the health effects of ingested asbestos. Further information will also be provided by the results,of a large scale animal feeding study supported by the Food and Drug Ad ministration, CPA, and the National Institute of Environ mental Health. Results of this study will not be avail able for several years. 9 CTD032437 SUMMARY A study of the asbestos-cement pipe distribution systems in Connecticut water supplies was performed as background for an epidemiology investigation designed to determine whether there were differences in cancer ex perience between population groups exposed to asbes-toscemcnt pipe distribution systems and those exposed to distribution systems of other materials. Connecticut townships were ranked according to the population served by A/C pipe, the age and length of the pipe, and the aggressiveness of the water transported. Towns studied contained from less than 1 to over 100 miles of A/C pipe. The majority had A/C pipe that was at least 25 years old and most had water which would be considered aggressive based on the chemical parameters of pH, alkalinity, and calcium hardness. The preliminary findings of the epidemiology study did not show any excess in cancer incidence for stomach, colon, or rectum in Connecticut townships during 19351973 that could be related to the use of asbestos-cement pipe for drinking water. Since the safety of asbestos in drinking water can not be proven or disproven at this time, current public health recommendations about the use of A/C pipe for potable water systems should be based primarily on the * aggressiveness of the water. Closed pipeloop studies and field sampling currently in progress are expected to provide data on which water quality parameters have the most affect on the release of fibers from the inte rior of A/C pipe. On the basis of the analytical results from thirtyone samples collected at the water sources prior to entering the distribution system, it was concluded that the population served by public water systems not using asbestos-cement pipe were not exposed to significant amounts of naturally occurring asbestos in water. Chrysotile fiber counts from 19 samples collected after water had passed through various lengths of asbestoscement pipe ranged from below detectable limits (10,000 fibers/1 iter) to 700,000 fibers per liter. The lengths of the chrysotile fibers found ranged from 0.2 to 60 micrometers in length; 0.02 to 0.5 micrometers in width. ACKNOWLEDGEMENTS The authors wish to acknowledge the valuable as sistance of Patrick J. Clark, Exposure Evaluation Branch, Health Effects Research Laboratory (UERl) in sample preparation and electron microscopy analysis, Cynthia Sonich, Epidemiology Branch, I1ERL, in data organization and statistical analysis, and Mrs. Barbara L. 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Sensing and Assessment, Pub. by IEEE, Piscataway, NJ. 34(2): 1-9. 24. Cooper, R.C. and J.C. Murchio, 1974. Preliminary Studies of Asbcstiform Fibers in Domestic Water Supplies, Final Report to the Aerospace Medical Research Laboratory, Wrighu-Pnttcrson Air Force Base, Ohio (available from NT 15, U.S. Dept, of Commerce &AD-A011-S55.) CTD032440 MICROMETERS w CTD032441