Daily Archives: May 25, 2011

Skeletal Fluorosis from Brewed Tea

Some foods are known to have a very high fluoride content…such as brewed tea…as illustrated in the recently published study below.  In comparison fluoridation of drinking water at the optimal dose of ~1 mg/L is a minor source of exposure and well below the USEPA MCL of 4 mg/L.

J Clin Endocrinol Metab. 2011 May 18.
 
Skeletal Fluorosis from Brewed Tea.
 
Izuora K, Twombly JG, Whitford GM, Demertzis J, Pacifici R, Whyte MP.
Division of Endocrinology, Metabolism, and Lipids (K.I., J.G.T., R.P.), Department of Medicine, Emory University, School of Medicine, Atlanta, Georgia 30322; Department of Oral Biology (G.M.W.), Medical College of Georgia, Augusta, Georgia 30912; Musculoskeletal Disease Section (J.D.), Mallinckrodt Institute of Radiology at Barnes-Jewish Hospital, Washington University School of Medicine, St. Louis, Missouri 63110; Center for Metabolic Bone Disease and Molecular Research (M.P.W.), Shriners Hospital for Children, St. Louis, Missouri 63131; and Division of Bone and Mineral Diseases (M.P.W.), Washington University School of Medicine at Barnes-Jewish Hospital, St. Louis, Missouri 63110.

Background: High fluoride ion (F(-)) levels are found in many surface and well waters. Drinking F(-)-contaminated water typically explains endemic skeletal fluorosis (SF). In some regions of Asia, however, poor quality “brick tea” also causes this disorder. The plant source of brick, black, green, orange pekoe, and oolong tea, Camellia sinensis, can contain substantial amounts of F(-). Exposure to 20 mg F(-) per day for 20 yr of adult life is expected to cause symptomatic SF. High F(-) levels stimulate osteoblasts and enhance bone apposition but substitute for OH(-) groups in hydroxyapatite crystals and thereby result in skeletal fragility and perhaps lead to secondary hyperparathyroidism. Beginning in 2005, we showed that daily consumption of 1-2 gallons of instant tea made from this plant can lead to SF.

Aim: We describe a 48-yr-old American woman who developed SF from brewed tea.

Patient and Methods: Our patient had elevated bone mineral density revealed by dual-energy x-ray absorptiometry (spine Z-score, +9.9), severe chronic bone and joint pain, and kyphosis after consuming 1-2 gallons of brewed orange pekoe tea daily for more than three decades. F(-) levels were high in her serum, urine, and clippings of fingernails and toenails, as well as in our reproduction of her beverage. Renal function was normal. She had vitamin D deficiency. Elevated serum PTH levels were unresponsive to adequate vitamin D supplementation. Pain resolved over several months when she stopped drinking tea and continued ergocalciferol.

Conclusion: Our patient shows that SF can result from chronic consumption of large volumes of brewed tea.

Abstract source: National Library of Medicine

On-Line Chlorine Monitor Calibration

Below is a copy of a memorandum being distributed by USEPA’s Office of Ground Water and Drinking Water – Technical Support Center that describes calibration requirements of on-line chlorine monitors.MEMORANDUM

SUBJECT: Complying with Calibration Requirements of On-line Chlorine-monitors

FROM:    Gregory Carroll, Director
         Technical Support Center

TO:      Regional Drinking Water Branch Chiefs
         Regional Certification Authorities
         Regional Certification Officers
Our office recently learned of confusion regarding the calibration requirements of on-line chlorine-monitors employed at public water systems to continuously measure disinfectant residuals. Continuous monitoring of disinfectant residuals is addressed in both the Ground Water Rule (GWR) and the Surface Water Treatment Rule (SWTR). The Surface Water Treatment Rule [141.74(a)(2)], indicates that, “Instruments used for continuous monitoring must be calibrated with a grab sample measurement at least every five days, or with a protocol approved by the State.” The Ground Water Rule repeats these requirements at 141.403(b)(3)( i) by referencing 141.74(a)(2). Therefore, when using a continuous chlorine disinfectant residual monitor for compliance with these rules, the unit must be calibrated with a grab sample at least every five days, or with a protocol approved by the State. This requirement applies to all methodologies used for continuous monitoring.

Consistent with the regulations, and presuming State concurrence, utilities can operate their continuous chlorine disinfectant residual monitor under the requirements of EPA Method 334.0, approved as an “alternate testing method” on November 10. 2009 (74 FR 57908). Once routine operation of the continuous monitor is achieved by meeting the demonstration of capability requirements, the method specifies that a calibration check standard is to be run at least every seven days. Therefore routine re-calibration is not required as long as (1) the weekly calibration check meets the quality control requirements of the method and (2) this calibration verification protocol and frequency are approved by the State (i.e., in lieu of re-calibration every five days).

If you have any questions regarding this matter please contact Steve Wendelken of the Technical Support Center at wendelken.steve@epa.gov or (513) 569-7491.

cc: Pamela Barr, SRMD
    Ann Codrington, DWPD
    Mindy Eisenbe rg, DWPD
    Michael Finn, DWPD
    Dan Hantman. TSC
    Ed Moriarty, DWPD
    Carrie Wehling, OGC
    Steve Wendelken, TSC