Epidemiologic Notes and Reports Lead-Contaminated Drinking Water in Bulk-Water Storage Tanks -- Arizona and California, 1993

Lead poisoning is a major environmental health problem for children in the United States (1,2): during 1988-1991, approximately 1.7 million U.S. children aged 1-5 years had elevated blood lead levels (BLLs) (greater than or equal to 10 ug/dL) (3). To determine the source of lead exposure for children with BLLs greater than or equal to 20 ug/dL, the Arizona Department of Health Services (ADHS) conducts environmental investigations. In 1993, as a result of investigations of increased BLLs in two children in southwestern Arizona, ADHS detected lead levels approximately 30 times the Environmental Protection Agency (EPA) action level of 15 parts per billion (ppb) in bulk-delivered drinking water in the homes of these children. Because two of the three companies that supplied bulk water to southwestern Arizona were based in California, ADHS notified the California State Department of Health Services (CSDHS) about the problem. As a result, CSDHS conducted a separate investigation and identified one child with an elevated BLL whose drinking water sources included bulk-delivered water with lead levels exceeding EPA standards. This report summarizes the investigations of elevated BLLs in these three children and high lead levels in bulk-delivered drinking water in Arizona and California. Arizona

In July 1993, routine screening by ADHS for lead poisoning detected a BLL of 42 ug/dL (CDC BLL of concern=10 ug/dL) in a 6-month-old infant in Yuma County, Arizona. To determine the source of lead exposure, ADHS initiated an environmental investigation. Lead was not detected in a first-draw water sample from the kitchen faucet, which was connected to a private well. However, the parents reported that the child's formula was prepared using bulk-stored water, and a first-draw water sample taken through the brass fitting of a bulk-water storage tank contained 495 ppb lead. Other potential environmental sources of lead included peeling lead paint on the outside of the house and on one kitchen wall covered with wallpaper. ADHS advised the parents to stop drinking bulk-stored water, informed them about professional paint removal and encapsulation, recommended measures to prevent lead exposure, and notified the water-delivery company about the high lead level in the bulk-stored water.

In August 1993, a BLL of 37 ug/dL was detected in a 12-month-old child in Yuma County who was tested by ADHS for lead poisoning following a complaint of abdominal pain. Lead was not detected in a first-draw water sample from the kitchen faucet, which was connected to the municipal water supply. However, the parents reported that the child's source of drinking water was bulk-delivered water, and a first-draw water sample obtained from a kitchen faucet supplied by a bulk-water storage tank contained 450 ppb lead. The investigation also identified lead-contaminated soil (68 ppm) at a relative's home where the child routinely stayed during the day. ADHS advised the parents to stop drinking bulk-stored water, recommended measures to prevent lead exposure, and notified the water-delivery company about the high lead levels in the bulk-delivered water. Two weeks after the first-draw sample was obtained, lead levels in water taken through the brass fitting on the tank and directly from the tank were 1050 ppb and 602 ppb, respectively.

Because the source of bulk-delivered water for both cases was a California-based water-delivery company, ADHS notified CSDHS about the potential problem of lead-contaminated bulk-delivered water. California

In November 1993, a newspaper report about lead-contaminated bulk-delivered water prompted parents in Imperial County, California, to have their 14-month-old child screened for lead poisoning by the county health department. A BLL of 15 ug/dL was detected in the child. The parents reported that the child's drinking water sources were bulk-delivered water and surface water. A first-draw water sample from the kitchen faucet, which was connected to a bulk-water tank supply, contained 66 ppb lead. After running the water for 3 minutes, a second-draw water sample from the same faucet contained 9 ppb lead. A first-draw water sample from the refrigerator faucet, also connected to the bulk storage tank, contained 50 ppb lead. First-draw water samples obtained from two other faucets in the house, which were connected to a surface water supply, had lead levels lower than the detection limit of 5 ppb. No other potential sources of lead exposure were identified. The county health department advised the parents to stop drinking bulk-delivered water and recommended measures to prevent lead exposure. Investigation of Bulk-Water Sources

ADHS identified three water companies (two based in California and one based in Arizona) that supplied bulk water to southwestern Arizona. ADHS obtained water samples from 96 residential and business storage tanks serviced by the two California water companies; no water samples were obtained from the Arizona company because the company used plastic tanks and fittings. Samples were drawn directly from the tanks, from the brass fittings on the tanks, and from the kitchen sinks. Twenty-two (23%) of the 96 water samples contained lead levels exceeding EPA's action level. Samples from three bulk-water delivery trucks containing the source water for the storage tanks met EPA drinking water standards (i.e., less than 15 ppb lead).

Both California water companies notified their customers about the possibility of lead leaching from soldered seams and brass fittings in bulk-water storage tanks. In addition, one company identified the sources of lead in its bulk-delivered water: lead solder in tanks manufactured before March 1987, lead-containing brass fittings, and lead solder in household plumbing. The company initiated replacement of all lead-soldered storage tanks and brass fittings and informed homeowners of the probable presence of lead-soldered household plumbing. Reported by: NJ Peterson, MS, FW Chromec, PhD, CM Fowler, MS, P Arreola, MS, E Arvizu, B Erickson, PhD, P Alder, J Soltis, L Sands, DO, State Epidemiologist, Arizona Dept of Health Svcs. V Freeman, M Miramontes, M Johnston, Imperial County Health Dept, El Centro; J Flattery, MPH, R Gambatese, MPH, S Gilmore, MA, R Ehling, MD, AM Osorio, MD, L Barrett, DVM, C Lee, PhD, I Small, GW Rutherford, III, MD, State Epidemiologist, California State Dept of Health Svcs. Lead Poisoning Prevention Br, Div of Environmental Hazards and Health Effects, National Center for Environmental Health, CDC.

Editorial Note

Editorial Note: In southwestern Arizona and southeastern California, bulk water delivered and stored in tanks is not an uncommon source of drinking water. Approximately 2500 residences and businesses in southwestern Arizona and 8500 in Imperial and San Diego counties, California, are served by bulk-delivered water. Although lead in the bulk-delivered water probably contributed to the high BLLs detected in the children described in this report, the role of other potential sources of lead could not be determined.

The Food and Drug Administration (FDA) has proposed a provisional total tolerable intake level of lead for infants and children of 6 ug daily (4). U.S. residents ingest an estimated 5-11 ug of lead daily (5). On average, lead-containing drinking water is estimated to contribute 10%-20% of the total lead exposure for children in the United States (5). For infants and young children, ingestion of only 0.5 L of water per day with a lead concentration of 450 ppb (450 ug/L) will result in a daily dose of lead of 225 ug -- a level approximately 38 times higher than FDA's total tolerable intake level. The children described in this report ingested daily doses of lead from six to 41 times higher than the total tolerable intake level.

Federal legislation authorizes both FDA and EPA to regulate drinking water (6): the Food, Drug, and Cosmetic Act * empowers FDA to regulate drinking water (including bottled water and water used in food and for processing), and the Safe Drinking Water Act ** and other statutes enable EPA to regulate public water systems that provide drinking water for human consumption. In 1986, an amendment to the Safe Drinking Water Act *** prohibited the use of 1) water pipes and pipe fittings with greater than 8% lead and 2) solder and flux with greater than 0.2% lead in public water systems and plumbing (in residential or nonresidential facilities) that provide drinking water for humans and are connected to public water systems (5). Although lead-containing faucets and fittings may comply with the lead restrictions in the Safe Drinking Water Act, lead from these fixtures can leach into the water supply and result in lead levels in drinking water that exceed EPA's action level. To address this concern, guidelines that further limit the amount of lead in plumbing fixtures are being developed by EPA, National Sanitation Foundation International (a nonprofit organization that tests and certifies water products), and the Plumbing Manufacturers Institute.

References

1. CDC. Preventing lead poisoning in young children: a statement by the Centers for Disease Control. Atlanta: US Department of Health and Human Services, Public Health Service, CDC, October 21, 1991.

2. Committee on Environmental Health, American Academy of Pediatrics. Lead poisoning: from screening to primary prevention. Pediatrics 1993;92:176-83.

3. Brody DJ, Pirkle JL, Kramer RA, et al. Blood lead levels in the US population: phase I of the Third National Health and Nutrition Examination Survey (NHANES III, 1988 to 1991). JAMA 1994;272:277-

5. Food and Drug Administration. Lead-soldered food cans: proposed rule. Federal Register 1993;58;33860-71.

6. Bolger PM, Carrington CD, Capar SG, Adams MA. Reductions in dietary lead exposure in the United States. Chemical Speciation Bioavailability 1991;3:31-6.

7. US Environmental Protection Agency/Food and Drug Administration. Memorandum of understanding between the EPA and FDA. Federal Register 1979;44:42775-8.

• 21 U.S.C. 301 et seq.

** 42 U.S.C. 300 et seq, 1974 ed. *** 42 U.S.C. 300 et seq, 1986 ed.

Disclaimer   All MMWR HTML versions of articles are electronic conversions from ASCII text into HTML. This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the electronic PDF version and/or the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices.

Page converted: 09/19/98

HOME  |  ABOUT MMWR  |  MMWR SEARCH  |  DOWNLOADS  |  RSS |  CONTACT POLICY  |  DISCLAIMER  |  ACCESSIBILITY

Morbidity and Mortality Weekly Report Centers for Disease Control and Prevention 1600 Clifton Rd, MailStop E-90, Atlanta, GA 30333, U.S.A Department of Health and Human Services

This page last reviewed 5/2/01