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Home My WebLink About1998-03-02 City Council (4)City City of Palo Alto Manager’s Report TO:HONORABLE CITY COUNCIL FROM:CITY MANAGER DEPARTMENT: UTILITIES DATE:MARCH 2, 1998 CMR:144:98 SUBJECT:TOTAL TRIHALOMETHANES (TTHMs) IN DRINKING WATER This is an informational report and no Council action is required. BACKGROUND According to recent news reports, two studies conducted by the California Department of Health Services and published in the March issue of The Journal of Epidemiology suggest that there may be a link between miscarriages and disinfection by-products (Total Trihalomethanes or TTHMs) in drinking water. TTHMs in drinking water form when chlorine or other disinfectants -- necessary to prevent waterborne diseases -- react with naturally occurring organic matter in water. Chlorine has been used for nearly 100 years as a disinfectant for water supplies due to its effectiveness at killing bacteria and viruses in water. The Safe Drinking Water Act (SDWA), which was enacted by Congress in 1974, gave the U.S. Environmental Protection Agency (EPA) the Federal authority to. establish primary and secondary drinking water standards. In 1979, the EPA adopted a regulated limit on the amount of TTHMs allowable in drinking water of 100 parts per billion, or 100 micrograms per liter. Primary drinking water standards were established to protect health and, if exceeded, require public notification. TTHMs are included in the primary drinking standards. The City is required to notify the community any time the water is not in compliance with these standards. Secondary drinking water standards were established for aesthetic reasons which include taste and color. DISCUSSION Staff conducts tests for TTHMs on a quarterly basis by collecting water samples at four locations in Palo Alto, approved by the California Department of Health Services, for analysis. Once collected, the samples are analyzed by the Regional Water Quality Control CMR:144:98 Page 1 of 2 Plant laboratory and the results are sent to the Department of Health Services, in compliance with State and Federal law..For the last ten years, Palo Alto’s water supply has met or exceeded all State and Federal standards for primary and secondary drinking water standards. The maximum contaminant level permitted for TTHM’s in drinking water is an average Of 100 parts per billion over four consecutive quarters. In other words, a utility has not violated the standard unless the average of the system-wide averages of the most recent four quarters does not exceed 100 parts per billion. For example, in Palo Alto four samples are collected each quarter for TTHM’s testing and these results are averaged. Then the averages of the three previous consecutive quarterly results and the current quarter are averaged to determine whether the utility is in compliance with the TTHM standards. An informational campaign will be implemented to inform tl~e community about this issue. Customer-contact staff will be trained to answer questions, fact sheets concerning TTHMs by the Department of Health Services will be made available to customers, phone numbers to relevant agencies will be provided, and the 1997 water quality analysis report will be distributed with the April utility bills. Staff will be following this issue closely and will continue to comply with any existing or future standards developed by the State Department of Health Services. ATTACHMENTS Attachment 1: Published abstracts for the two articles Attachment 2: Palo Alto’s average TTHM results over 10 years Attachment 3:1996 Water Quality Analysis bill insert Attachment 4: DHS Fact sheet - Trihalomethanes Attachment 5: DHS Fact sheet - Water Consumption PREPARED BY: DEPARTMENT HEAD: Linda Clerkson, Public Relations Manager CITY MANAGER APPROVAL: HARRISON Assistant City Manager CMR:144:98 Page 1 of 2 ¯ ’~’~Abstracts of two articles published in the March edition of Journal ofEpide~nology. "A Prospective Study of Spontaneous Abortion: Relation to Amount and Source of Drinking Water Consumed in Early Pregnancy" Shanna H. Swan, Kirsten Waller, Barbara Hopkins, Gayle Windham, Laura Fenster, Catherine Schaefer, and Raymond R. Neutra In 1992, we published four retrospective studies, conducted primarily within a single California county, which found higher spontaneous abortion rates amongwomen who drank more tapwater than bottled water in early pregnancy. The current prospective sicudy extends that investigation to other water systems. Pregnant women from three regions in California were interviewed during their first trimester. Multivariate analyses modeled the amount and type of water consumed at 8 weeks’ gestation in each region in relation to spontaneous abortion rate. In Region I, which was within the previous study area, the adjusted odds ratio (OR).comparing high (>6 glasses per day) consumption of cold tapwater with none wb, s 2.17 [95% confidence interval (CI) = 1.22-3.87]. "Furthermore, when women with high cold tapwater and no bottled water consumption were compared with those with high bottled water and no cold tapwater Consumption, the adjusted odds ratio was 4.58 (95% CI = 1.97-10,64). Conversely, women with high bottled water consumption and no tapwater had a reduced rate of spontaneous abortion compared with those drin "king tapwater and no bottled water (adjusted OR = 0.22; 95% CI = 0.09-0.51). Neither tap nor bottled water consumption altered the risk of spontaneous abortion in Regions II and III. Although controlling for age, prior spontaneous abortion, race, gestational age at interview, and weight somewhat strengthened the association in Region. I, the distribution of these confou,nders did not vary appreciably across regions. This study confirms the association between cold tapwater and spontaneous abortion first seen in this county in 1980. If causal, the agent(s) is not ubi@itous but is likely to have been present in Region I for some time. "Trihalomethanes in Drinking Water and Spontaneous Abortion" Kirsten Waller, Shanna H. Swan, Gerald DeLorenze, and Barbara Hopkins Trihalomethanes (chloroform, bromoform, bromodichloromethane, and chlorodibromomethane) are common Contaminants of chlorinated drinking water. Although animal data indicate that these compounds may be reproductive toxicants, little information exists on their relation to spontaneous abortion in humans. We examined exposure to trihalomethanes and spontaneous abortion in a prospective study of 5,144 p~’egnant women in a prepaid health plan. Seventy-eight drinking water utilities provided concurrent trihalomethane sampling data. We calculated total trihalomethane levels by averaging all measurements taken by the subject’s utility during her fi~’st trimester. We calculated exposures to individual trihalomethanes in an analogous manner. Women who drank >5 glasses per day of cold tapwater containing >75 gg per liter total trihalomethanes had an adjusted odds ratio (OR) of 1.8 for spontaneous abortion [95% confidence interval (CI) = 1.1-3.0]. Of the four individual trihalomethanes, only high bromodichloromethane exposure (consumption of>5 glasses per day of cold tapwater containing >18 ~.tg per liter bromodichloromethane) was associated with spontaneous abortion both alone (adjusted OR = 2.0; 95% CI = 1.2-3.5) and after adjustment for the other trihalomethanes (adjusted OR = 3.0; 95% CI = 1.4-6.6). II 1996 Water Analysis for Palo AIt( This table lists the con- centrations of various chemical and biological parameters in PaloAlto s water supply. By law, raw water must be tested to ensure it is free from industrial or sanitary contamination. Treated water must also meet both primary and sec- ondary standards. Primary standards regu- late substances that may affedt public health. Secondary standards ad- dress aesthetic qualities such as taste and odor. The Maximum Contami- nant Level (MCL) is the standard set by both state and federal governments. The analysis shows that all elements detected in Pale Alto’s water supply were below state and federal MCLs during 1996. In general, these findings show that the water that Pale Alto receives from the San Francisco Public Utilities Commission (SF-PUC) and supplies to the community is of very high quality and safe to drink. Additionally, the water analysis shows that this water is very soft and contains few miner- This chart is bated on informationprovided, in March 1997, by the SanFrancisco Pubhc Utilities Commii- tion to the Ci~7 of Polo Alto Utihtie+. This information meets all of therequirements of Sectlon 64463.1 ofCalifornia Domestic Water Quahty and Monitoring Regulations for allpublic water supply agencies to send an annual water quali~7 report toout’Comers. It also satisJ~et the reporting requirements of the U.S.Environmedtal Protection Agency (USEPA) and the California Depart- ment of Health Services. PALO ALTO WATER DISTRIBUTI~)N SYSTEM MaximumContaminantParameterUnitLevel Range~ ....A_y=era_~_qCLARITYTurbidRy.....................................................................................................: NTU 1 (I)0 1.0 9 0 3MICROBIOLOGICAL - COLIFORM BACTERIATotal Colflorm Bacteria ...............% monthly posdwe sample .........SAMPLES 5 0-2E. Cob .........................................# monlhly pos~hve sample ..........POStTIVE 0 none INORGANIC CHEMICAL Fluodde added by Ctty (8) .........................................................................m~/L 1.4-2.4 0 4.1.2 0.98Free Chlorine ............................................................................................m~..NS 0. 1-1 .05 SAN FRANCISCO PUC TREATED WATER ORGANIC CHEMICALS(a) Volatile Organic Chemicals (VOCs) ¢2) ......................uoJL 0.5-~760 ¢3)<0.6 <.06Methyl Terlie~ Butyl Ether (MTBE) ............................................................ug/L NS <0.5 < 05t, 1,2-Trichloro- ~ ,2, 2- Ttflluoromethano (Freon 113) ...............................................ug/L 1"200 <0.5 <.05 (b) Synthetic Organic Chemicals (SOCs) (5)~drm ...........................................................................................................u~NS .~.0v~<oo76eenzo(a)pyrene ..........................................................................................ug/L 0.2 <0. I <.01Bulachlo¢ .....................................................................................................ug/L NS <0.38 <0.38Carbaryl...............................................................................; ......................~g~.NS <5.0 <5.0O~camba ......................................................................................................NS <0.081 <0.081D~eldnn ........................................................................................................ug/L 0.02 <0.02 <0.02Dmoseb .......................................................................................................ug/L 7.0 <2.0 <2.0Diquat.........................................................................................................uoJL 20.0 <4.0 <4.03-Hydroxycarboluran ..................................................................................ug/L NS <3.0 <3.0Melhomyl....................................................................................................ug/L NS <2.0 <2.0Meleiachlor .................................................................................................ugiL NS <0.5 <0.5Metdbuzin...................................................................................................ug/L NS <0.5 <0.5Oxamyl .......................................................................................................ug/L 200 <20.0 <20Ptopachlor...................................................................................................ug/L NS <0.5 <0.5 INORGANIC CHEMICALSAsbestos (6) (7) ..........................................................................................MFL 7 <0 026 <0.026Aluminum....................................................................................................ug/L 1000 57-115 66Anllmony .....................................................................................................ug/L 6 <5 <5Arsenic..................................................................~ .....................................ug/L 50 <2-2 <2Barium .........................................................................................................ugh.1~0 6-28 17Be~/Ihum .....................................................................................................ug/L 4 <1 <1Cadmium .....................................................................................................ug/L 5 <IChromium...................................................................................................ug/L 50 <2 <2Cyanide (7) ................................................................................................rng/L 0.2 <0.1 <0,1Lead............................................................................................................ug/L 15 (9)<1 <1Mercury .......................................................................................................ug/L 2 <0.5 <0,5Nickel..........................................................................................................ug/L 100 <3 <3Nitrate (es NO,) ..........................................................................................m.q/L 45 <0.4-0.4 0.4N tr{te (as N) .,: ..........................................................................................m~/L 1 <0°05 <0 05N=trete and blitnte (as N) ............................................................................mg/L 10 <0.05-0 09 0.08Selenium.....................................................................................................ug/L 50 <5 <5Thallium .....................................................................................................ug/L 2 <1 <1 Radionuclides (~0) Total Alpha panicle .....................................................................................pci/L 15 . <0 96 -<0,96Tolal Beta particle .......................................................................................p~’~_50 <0.56 <0 56Radon .........................................................................................................pc~L NS <0.18 <0.18Strontium....................................................................................................pci/L 8 <0.14 <0.14Trihum .........................................................................................................pci/L 20000 <3.7 <3.7Uranium......................................................................................................pci/L 20 0.04-0.70 0.37 Chlodde .....................................................................................................mg/L 250 "4-17 10 Color ...........................................................................................................units 15 <1-6 3Copper.......................................................................................................ug/L 1000 <1-1Iron ..............................................................................................................ug~L 300 <5-40 2Manganese.................................................................................................ug/L 50 <3 <3Silver .........................................................................................................;; ~J~g~mu100 <1 <1Specific Conductance ....................................................................................900 42-213 126Sulfate........................................................................................................mg/L 250 1.3-12 6 6Total Dissolved Solids (’TDS) .....................................................................mg, q.500 24-121 72Zinc.............................................................................................................ug~50~0 <5 <5 Atkatinity (CaCO~) ......................................................................................mg/L NS 13-68 40Calcium .............’.. ................., .....................................................................mg/L NS 3.8-15 9 4Hardness (CaCO=) .....................................................................................mg/L NS 10-68 39Magnesium ................................................................................................mg~NS <0.2-6.7 3 5pH...............................................................................................................uniLs NS 8 9-9.6 9.2Phosphate .........................................................................................: ........m ,~.’L NS <0.05 <0 05Potassium.................................................................................................m~/L NS 0.2-0.9 0.5Sdica ..........................................................................................................m~/L NS 4-7 6Sod=urn .......................................................................................................m~1_NS <3-16 9 (I) Filtered w=ter 0.5 N"ru, unfiherd water 5,0 NTU, (.,o~ A~ion level.(2) SF-PUC hva also analTz~d additmna] 56 VOW, ~1 of which t~uhs were ~low (1@ B~d on ~u~ m~ured duflng calendar ~r 19’ ¯¯.<~) Mzxm~um contaminant !~d ~n~ for each anti. Bromo£o~m.,~,~ - milhg~ ~r [ie (parts Fer million)bdhon)u L(S) SF-PUC ~ctwtd waw~rs for mommong ogan addmon~ 40 -No Standard(6) Forfib~sovtr 10umlong ~U -Ntphdome~ricTurbld~¢yUn;t~(7) B~ed on ~u~ m~urtd durlng ~endar year 1995.~L - pic~u~i~ per li~(8) Fluudde st~d d~en~ on ~em~u~e,~l~m TRIHALOMETHANES IN,DRINKING WATER SPONTANEOUS ABORTION SUMMARY FEBRUARY 1998 AN,D []Trihalomethanes (chloroform, bromoform, bromodichloro- "~]ethane, and chlorodi- bromomethane) are common contaminants of chlorinated drinking water. They form when chlorine reacts with de- composing plant material, which is often found in water from surface sources. [] Although animal data sug- gest some of the trihalometh- ones may interfere with re- production athigh doses, little information exists on the re- lationship between trihalo- methane exposure and mis- carriage (spontaneous abor- tion) in humans. []We examined exposure to tri- halomethanes in relation to miscarriage in a studyofS,144 pregnant women living in three areas of California (centered in Santa Clara, Walnut Creek and Fontana). These women were interviewed early in preg- nancy ab6ut their water con- sumption and a va~riety of other factors that may infl uence preg. nancy outcome. (That study is discussed in further detail in Swan et al, an analysis con- ducted on the same data). []Eighty-five drinking water utilities served the pregnant women’s homes. These utili- ties provided records .of dis- tribution systemmeasure- ments oftotal trihalomethanes (TTHM) and, where available, the four individual triha[o- methanes. The TTHM level in a participant’s home tap wa- ter was estimated by averag- ing all measurements taken .by her utility dur]ng her first trimester. Tap water levels of the individual trihalometh- aries (chloroform, bromo- form, etc.) were estimated in the same manner. Women who drank five or more glasses per day of cold home tap water containing at least 75 ug per liter of TTHM had a miscarriage rate of 15.7%. Among other women (those who drank less than 5 glasses per day and/or.had tap water’contalning less than 75 I~g per liter of TTHM) the miscarriage rate was 9.5% (Adjusted odds ratio for mis- carriage of 1.8, 95% confi- dence interval 1.1-3.0). Of the four individual trihalo- methanes, only high bromo- dichloromethane exposure (drinking 5 or more glasses per dayof cold home tap water containing >18 Iz~L bromo~ dichloromethane) was asso- ciated with miscarriage both alone and after adjustment for the other trihalomethanes (adjusted odds ratio for mis- carriage of 3.0, 95% confi- dence interval 1.4-6.6). Given the widespread expo- sure to trihalomethanes, we recommend that additlon~l research be conducted to rep- licate our findings. ¯ 1 About this chlorination stu.dy: Call Dr. Kirsten Waller (301) 620-c~551 [] About the Pregnancy Out- come Study: Call. Dr. Shanna Swan (510) 450-381 8 u About water quality: Call David Spath (9"[ 6) 322-2308, or your local water utility TRIHALOMETHANES IN DRINKING WATER AND SPONTANEOUS ABORTION QUESTIONS AND ANSWERS FEBRUARY 1998 Q: 34~’n’at are trThalomethanes~, A: Trihalomethanes (chloro- form, bromoform, bromodi+ chtaromethar,e, and chlorodi- bromomethane) are common contaminants of drinking water that has been chlorinated or chioraminated. Trihalometh- ones form when chlorine reacts with certain acids-that come from decomposing plant mate- rial. Trihalomethanes are found ~ainly in water that originally came from surface sources, such as rivers and lakes. The amount of trihalomethanes in drinking water can change a lot from day to day, depending on the tem- perature, the amount of plant material in the water, the amount of chlorine added, and a variety of other factors. Q: What did your study,find? A: Women with high personal exposure to total trihaiometh- anes (1-i’HM) &~ring their first trimester o,~ pregnancy had a miscarriage rate of 15.7%, com- pared to a miscarriage rate of 9.5% among women with low TTHM exposure (adjusted odds ratio (OR) = 1.8, 95% confi- dence interva! 1.1-3.0). When. we looked .at the individual tri- halom, ethanes, only high per-. sonal exposure to bromodi- chloromethane (BDCM) was associated with miscarriage af- ter adjusting for the other tri- hal0methanes (adjusted OR = 3.0, 95% confidence interval 1.4-6.6). (See Definitionsbelow.) high personal TTHM exposure: low personal TTHM exposure: high personal BDCM exposure: low personal t~DCM exposure: drinkin8 five or more glasses per day of cold home tap water containing a~ least 75 lzg per liter of TTHM drinking less than 5 glasses per day of cold home tap wa~er or having home tap water containing less than 75 #g per liter of TTHM drinkinl~ five or more 81asses per ~lay of cold home tap water containin8 a~ least 18 ~= per liter of B DCM drinking less than 5 ~;lasses per day af cold home tap water or having home tap water contain[n8 less ~han 1 8 IJ.g per liter of BDCM Q: why was this study done? A: Sometrihalomethanes have been associated with poor re- productive outcomes in animals at high levels of expbsure. Two studies in humans have seen a relationship between trihalo- methane exposure and less- than.expected fetal weight gain, although another study d(d not see suck, an effect. Only one previous study has looked at miscarriage and trihalometh- ones and it did not find a clear- cut effect. Since we already had collecteda lot of wa~er informa- tion from a~ ~roup of pregnant women (this study is described in our companion report by Swan et el., 19~8), the U.S. En- vironmental Protection Asency gave us fundin8 to obtain addi- tiona! information about trihalo- methanes in the" pregnant women’s drinking water. Q: Who was in this study7 A: We s[udied 5,144 pregnant women living in three areas of California. They were recruked from the Santa Clara area (re- cru itm ent at Kaiser Santa Clara), the Fontana area in southern California (recruitment at Kaiser Fontana) or the Walnut Creek area (recruitment at Walnut: Creek, Martinez, Antioch and Pleasanton). The women were all members of the Kaiser Permanente Medical Care Pro- gram and were offered a chance to participate {n the study when they called to arrange their first prenatal visit. This stbdy looked at the same women, and the sam&pregnancies, as the study des--c’dbed in Swa.n et al., but for thi~ study we obtained addi- tional water quality information from the women’s drinking wa- ter utilities so that trihalometh- ones could be examined. Q: ,How did you do this study? A: Most drinking water utilities are required by state and federal regulations to measure the amount of TTHM in their system every three months. We "found out which utilities served the women in our study and, with the utilities’ full cooperation, obtained the records of the tri- halomethane measurements taken during the time our study participants were pregnant. T~e TTHM level in a participant’s home tap water was estimated by averaging all the water distri- bution system measurements taken by her utility during her first three months of pregnancy. Th is ’first trimester TTHM level’ was then examined together with the amount of tap water she reported drinking to create a personal TTHM exposure level. Personal exposure.levels of the individual trihalomethanes (chloroform, bromoform, etc.) were estimated in,the same manner. We did not measure the actual trihalb~ethanes els in the home tap water. Q: Were the trihalomethane results similar in all three areaz? A: With respect to TTHM, the association was somewhat stronger among women in the Santa Clara area than among women in the Walnut Creek area. Most women in the Fontana area received ground water, so there were very few women there with high TTHM levels. When we compared the composition of TTHM between the three study areas, there was a highe~ proportion of BDCM in the. Santa Clara-area women’s water than in the Walnut Creek- area women’s water. The asso- ciation between miscarriage and BDCM was similar in all areas. Q: .How did the risk of.miscar- riage vary with water intake and trihalomethane level? A: For TTHM, the highest risk wa~s seen in the 121 women who drank at least five glasses per day of cold tap water con- raining h;gh levels of TTHM (at least 75 IJ.g per liter). These women, who made up only 2% of the whole study group, had a miscarriage rate of 15.7%. Women whose home tap water. containedhigh levels of’FTHM butwho drank less than 5 glasses of tap water per day had a mis- carriage rate of 10.8%. Women who drank less than 5 glasses of tap water per day of water with low TTHM levels had a miscar- riage rate of 9.2%, and women who drank5 or more glasses of tap water per day of water with low TTHM levels had a miscar- r[age rate of 8.5%. When we looked specifically at BDCM levets, the differences were more pronounced. Of women who drank at least five 81asses per day of cold tap water, those whose water containedhigh lev- els Of BDCM (at least 18 IJ.g per liter) had a miscarriage rate of 16.4%, whereas those with lower levels of BDCM had a miscarriage rate of 6.1%. Women who drank tess than 5 glasses of tap water per day had miscarriage rates of 9.4% and 10.2% (high and low levels of B DCM, respectively). Q: Did you take water con- sumed at work and other places into account? A: No, we only had informa- tion about exposure to trihalo- methanes via home tap water. However, to see what sort of effect not having this informa- tion might have had on our re- sults, we looked at miscarriage rates by emplo~,ment status. We thought that our estimate of TTHM exposure for women who were not employed outside the home might be more ~ccurate than for women who were em- ployed. As it turned out, the association between high per- sonal TTHM exposure and mis- carriage was twice &s strong among women not employed outside the home compared to employed women. Q: Do the children born to women with high personal ex- posure to TTHM have more blrth defects or other problems? A: We didn’t have a big enough study to look at birth defects. Since about 3% Mall babies are ’born with birth defects, in the 121 women with high personal exposure we would expect only 3-4 birth defects in all. We are curr~ly analyzing our data to see iftrihalomethanes are asso- ciated with poor fetal weight gain or premature delivery, but we clon’t have any results about this yet. Q: Why is drinking water chlo- rinated? A: Drinkingwater is often chlo- rinated (or chloraminated) to kill bacteria and viruses that could cause serious illnesses. Overall, chlorination of drinking water has benefited the public health enormously. There are other methods of disinfecting public drinking water, but they are of- ten more expensive, and the potential health effects of using these other methods are in gen- era! less well understood. Q: How common is itfor drink- ing water to contain high levels of TTHM~. A: TTHM concentrations in tap water can vary greatly from place to place, and ffo,m time to time, dependin8 on the source of the water, how it is treated, and o~her factors. In our study, 18% of the participants received we- tar during their first trimester which we estim.ated contained at least 75 p.g of’FFHM per liter, and 13% had water with at least 90 p.g per liter. Q: is there a regulatory stan- dard for these chemicals in drinking water? A: Drinking water utilities that use chlorination are required by law to sample water throughout their distribution system at least once a quarter, average the TTHM measurements, and repor~ the results to the state. The Maxi- mum Contaminant Level (MCL) permissible for TTHM in drink- ing water by State and federal law is currently an average of 100 p.g per liter over four con- secutive quarters. In other words, a utility has no[violated the stan- dard unless the average of the system-wide averages over the past year is over 100 #g per liter. The water in the three study ar- eas met all Sta~e and federal drink- ing water.standards for TTHM. There are no standards for the individual tdhalomethanes. Q: I am pregnant. Should I stop drinking my tap water? A: First of all remember that it is important to drink lots of liq- uids during pregnancy. Keep fol- lowing the advice which your physician or midwife has given you. This study presents a new findi% which should be con- firmed by other studies before any firm recommendations can be made. In the meantime, if you are concerned about your tap water you can ask your wa- ter utility (or look at your annual water qua!ity statement) to see if your tap wate’!s frequently high in TTHMs. If it is and this con- cerns you, you have several options you can consider, at- though our study did not prove that miscarriage rates were lower in women making these choices. ~1 You can boll your water for one minute and then let it: stand in an open container in the refrigerator for several hours beforedrin kin8 it. Same studies .suggest that this may lower TTHM levels, although this is not yet established. Boiling water for more than a minute may concentrate met- als if they are present and , m.ay affect taste. 111 You can use a carbon-acti- vated filter, which should re- move most trihalomethanes as long as you follow the rnanufac(urer’s recommen- dations to change the filter regularly. m You may choose tO drink bo~led water. Bottled waters tend to be low in TTHM, thoul~h they can vary widely. Q: What is the California De- partment of Health Services doing next to look at the issue oftrihalomethanes in drinking water? A: The EPA is funding addi- tional studies which.will im- prove our understanding of chic- rination by-products as .well as improve our estimates of indi- vidual exposures. About this chlorination study: Call Dr. Kirsten Waller (3131) 620-9S51 [] About the Pregnancy Out- com__~e~$tudy: Call Dr, Shanna Swan (510) 450-361 8 [] About waterquality: Carl David Spath (916) 322-2306, or your l~¢al water utility EB.-II’98(~D) 11:03 Karl Stinson TEL:916 32~ 2306 Pag= B8? miscarriage rate of 17.9%, ’,.vhile those who drank only bottle water had a miscar- rio.go rate of 6.5%. Similar (bu~ less marked) dlf- ferences in miscarriage tate~ were seen among women drinking less waler, but. even amon~ those drinking .II~an 1 ~lass per day ~here was a siBnlficanI difference. The4e differences were notseen in oqr other two study areas, c~verall. However, a separate analysis (waller el al, 1998) looks at miscarriage rales iq re. lotion to products of chlorina- tion in the water these women drank. In this analysis, miscar- riage rates were elevated among women w~o drank large amounts of tap wa~er contain- in8 high levels e~ thgse prod. uc~s, regardless of~he s[udyarea. Q: Wa~ the rate ofmisca~;rlage higher lhan e,pected in your study/ A: No: Overall the miscarriage rate in this study was consistent with other studies on medi- cally confirmed miscarriages (about "1 0%),. Q: What about theSanta Clara area? A: Among women living in the Santa Clara area, a high miscar- riage rate was seen in lap water dri Qkers. However, more women in this area drank bottled water than tap waler, and those women had lower miscarriage rates, so averaged over all womerh The miscarriage rate was actually slightly less In this area (about g%). Q: Could Ihelawermiscarriage rate in botlled water drinkers in the Santa Clara area be due to other factors such as younger age or healthier habits? A: We don’! think so, We ex- am ined our dala For factors such as age, previous miscarriage: weight, smoking, alcohol intake and stress. Some of these did differ between tap and bottled water drinkers, and these differ- ences were all taken into a=- coun! in our ;analyses. Q: Does the a~soclation be. Iwe~n lap water and miscarriage vary by utility or location wltMn Ihe Santa Clara study area7 A: Our results reflect lhe over- all, or average, experience of women in this study are.",. These women received water t’tom sev- eral sources, delivered by many different util,ties. Our study was not designed to compare risks between water utllhies or small areas and we do not have data to reliably estimate such rates. We will be planning further analyses that may help answer this question. Q: Did you find evidence of olher health problem~ in the Santa Clara area, such aa in- crea~ed rates of birth defect~ or cancer? :A; Our s~udy was only designed to look at risk of miscarriage. However, based on rates of blr~h def’ec~s routlnely collected bythe Callt’omla Birth. Defects Moni[or- ing Program, Ihere was no excess of birlh delec{s; in our study ~pu- ladons we would expect ~a see binh de~c~s in 3% bu~ found ~hem only in abou[ 2%, The Inci- dence roles for cancer in San~a Clara are sl~ghdy below the stale average for bo~h males and males, based on datafrom Californ;a Cancer Registry. Q: .I am pregnant. Should ! stop drinking .my lap water? A: Bo,’h you and your develop- ing fetus need a lotof fluids. Folio,’,, your health care provider’ s r~comrnendation with respect to dr,nking w~ter. We are no: making any health tacos. menda~i0ns at this time because our data do not paint m a dear altern~,ive. Howevor, there are sew, to1 cptlons you can consider, although our sludy did hal prp.ve that miscarriage ra~es were lower in women making ~hese choices: ¯You can boil your water for one minute and then refriger- -ate It in an open container for several hours hot’ore drin’kin# il. (Some studies sugges! that . this may allow some agents in water, such as .trihalometh- ones (by.products of chlori- nation), to decrease, a khough this is not ye~ established,) Boilin~ wate[ longer ~han one miAute may concemra~e ~oci metals like lead, if present. ~ You maychose ~o drinkbo~led . water. (HoweveG our ~udy ~.-I’I’98(~ED) 11:03 TEL:916 3215 2306 .........~’ibo8" was not designed to examine specific brands, and there is no guarantee that bottled wa- ter is safer than tap water. You can use an approved car- ban Jilter. (:These devices only f’uncdon if re~,hlarly serviced,} Q: Can l usemywaterformak. ing iu{ce, ¢ooklng or making my baby’s formula? A: Ii~ your are conceme.d, you can follow the options listed above for these uses of water, Q: I am pregnant, Will show- ering, bathing or swimming In, crease my risk of miscarriage~ A: We looked at the amount t~me women spent in the shower and found litde or no increased risk due to long showers. Women who swam actually had a somewhat lower risk, but that could be because they were healthier, or could reflect the benefir.s of exercise. Q: Was the water tested for chemical contaminants? A; Yes. The water in the th’ree study areas wasregularly monl- tared and tested in accordance with State and federal standards. Throughout these areas all wa- ter met these standards. Chlo. rine by-products ’and other chemicals were found, but all below regulatory levels, Q: What does the Department of Heallh Services do to assure the safely of water A; The Department regulates both tap and bottled waters and requires purveyors to regularly test for and report all contami- nants known to cause health problems so as to assure a safe drinking water supply. The De- partmen{ also participates In s~udles such as these to extend ou r knowledge about water and i~ safety. The Depa~ment re- po~s on ongoing research to keep the population informed. When solid evidence abou~ pre- viousl~ unrecognized hazards has been ~athered, ~he Depan- men~ pa~lcipates in se~[ng new regulations. Q: Are these resul{s due to~ chlurinalion of my water A: Although our companion paper (Wailer et all indicated an association between miscarriage and the levels ot’ chlorination by-products in ~he water, this idoes nor explain the Increase in the miscarriage ra~e reported in Swan e~ al, which was seen only In ~he Santa Clara area. Q: What are you doing to find the cause of this problem? A: Currently, the Department’s Drinking Water Program regu- lates 80 omaminants at levels designed ~o protect the public health. We are working with ~he Drinkin~ Water Program and the utilities to look foragems which may account for the find- i~gs in this study. The EPA is funding additional studies which will improve our understanding of chlorination by-products as well as helping to characterize the water in the Santa Clara area. We will be workin~ with the utilities and hooded water companies to bet- ter understand the differences between small areas and brands of bodied water. We will con, suit wkh e~pert scientists who may help us identify the cause of these I’indinss. About this study; Call Dr. Shanna Swan (510) 450-3818 About the chlorlnadon s~udy: Call Dr, Kirs[en’Waller (301) 620-9551 About water quality: Call David Spath (g161 322-230B, or your local water utilit;y