ESTIMATION OF FLUORIDE INTAKE BY IRANIAN POWDERED MILK-FED INFANTS

Transcription

1 359 Estimation of fluoride intake by Iranian powdered milk-fed infants 359 ESTIMATION OF FLUORIDE INTAKE BY IRANIAN POWDERED MILK-FED INFANTS Marjan Ghanbarian, a Maryam Ghanbarian, a,b Mohammad Hoseini, a Amir Hossein Mahvi a,c,d Tehran, Iran SUMMARY: Fluoride (F) intake by formula-fed infants is highly variable, depending primarily on the F content of the water used to dilute the concentrated liquid or powdered infant formula products. The aim of the present study was to estimate the F intake by Iranian powdered milk-fed infants by taking account of the F content in the drinking water in different areas of Iran and the F content in the commonly used brands of powdered milk. The results showed that many infants in some regions of Iran were exposed to higher F intakes from powdered milk formula than those of other regions with a lower drinking water F level. Only in Bushehr province was the mean provincial F level in the groundwater resources higher than the WHO guideline value of 1.5 mg/l (1.86±0.86 mg/l) and the mean F intake of the powdered milk-fed infants in this province was µg/kg body weight (bw)/day, less than the EPA s reference dose (RfD) of 60 µg/kg bw/day. The F intake of powdered milk-fed infants in the other areas in Iran which were studied ranged from µg/kg bw/day. Keywords: Fluoride intake by infants; Iran; Powdered milk; Powdered milk-fed infants; Reference dose (RfD). INTRODUCTION Fluoride (F) occurs in the environment in various ways and is found in the groundwater in many regions. 1 The relationship between tooth decay and the concentration of F in drinking water has been studied for many years in children of all ages. 2,3 Studies of 7 12 and yr-old children, who had lived since birth in the United States and in a Swedish city, respectively, demonstrated that enamel fluorosis was more prevalent in those who had been fed, during the first 3 or 4 months of their lives, by powdered infant formulas diluted with the local water supply than in those who had been breast fed. 4,5 The F in milk is absorbable, 6 and it seems quite essential that the F intake, in mg/kg body weight (bw)/day, is assessed during the years when children are at risk of fluorosis. The US Environmental Protection Agency (EPA) reference dose (RfD) for F is 0.06 mg/kg bw/day or 60 µg/kg bw/day but adverse effects have been described at lower doses. 7 Infants given powdered milk formula prepared with low-f bottled water 8 may receive a low F intake while infants given cooled tea containing additional F will receive a higher intake. 9 The object of the present study was to estimate the amount of F intake by powdered milk-fed infants (1 12 months). MATERIALS AND METHODS The F-intake in mg F/kg bw/day by powdered milk-fed infants, aged 1 12 months, was calculated by analysing the existing data on the F content in drinking a School of Public Health, Tehran University of Medical Sciences, Tehran, Iran; b Ministry of Health and Medical Education, Tehran, Iran; c Center for Solid Waste Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran; d For correspondence: Assistant Professor Amir Hossein Mahvi, Center for Solid Waste Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran; E- mail: ahmahvi@yahoo.com.

2 360 Estimation of fluoride intake by Iranian powdered milk-fed infants 360 water in 30 provinces of Iran 10 and the F content in the brands of powdered milk commonly consumed in Iran. 11 RESULTS Table 1 presents the range and mean F concentration in twelve powdered milk brands. Tab le 1. Total F content of twelve brands of Iranian baby powdered milk* Milk brand name F content (µg F/g) Range Mean Humana ± Humana ± 0.1 Humana ± 0. 3 Multi ± 0.14 Multi ± Bebelac ± 0.08 Bebelac ± Nan ± 0.09 Nan ± 0. 4 Sama Gold ± 0.09 Sama Progres ± Biomil ± 0.13 *Mahvi et al. 11 Based on the water intake in the 2004 EPA-822-R report on per capita water ingestion, the per capita water ingestion for infants (<1 yr) is (maximum 261) ml/kg bw/day and for children (1 10 yr) is 1 57 (maximum 92) ml/kg bw/day. 12 Table 2 shows the constant parameters that were used for calculating the daily F intake in different areas of Iran. Table 2. Constant parameters used for calculating F intake by powdered milk-fed infants Age (m onths ) Weight (k g) Powdered milk intake (g/day) F in powdered milk (median) (µg F/g powdered milk) F intake from powdered milk weight us ing the median value for F in powdered milk of 1.8 µg F/g powdered milk (µg F /kg bw/day) Water consumption* (ml/kg bw/day) (1.8) * EPA-822-R Report (2004). 12

3 361 Estimation of fluoride intake by Iranian powdered milk-fed infants 361 Table 3 shows the F intake by Iranian powdered milk-fed infants, as calculated by using the existing data, in the provinces of Iran, whose locations are shown in the Figure. Table 3. Fluoride intake by Iranian powdered milk-fed infants Province F content in tap water (mg/l)* F intake from tap water (µg F/kg bw/day) Total F intake in powdered milk formula made with tap water (µg F/kg bw/day) * Mesdaghinia et al. 10 DISCUSSION The National Research Council declared that, for the US population, diet was the second largest source of F intake after drinking water. 13 As seen in Table 3, the total F intake calculated in all of the provinces is lower than EPA s reference dose (RfD) for F of 60 µg/kg bw/day.

4 362 Estimation of fluoride intake by Iranian powdered milk-fed infants 362 Figure. Location of the provinces in Iran shown in column 1 of Table 3. There is a significant difference between the F intake from water and the total intake. Note that the total F intake in column 4 of this table shows only the estimated F intake from powdered milk made with tap water and does not include F intakes from other sources, such as commercial beverages (which are often made with fluoridated tap water), toothpaste, tea, or food. When these other sources of F intake are included, the total F intake for many members of all age groups exceeds the EPA s reference dose. A study of mean F intake from Japanese infant milk formulas (IMFs) showed that the F intake ranged from 39 to 134 µg/ day with distilled water and from 78 to 258 µg/day with 0.13 mg/l fluoridated water, respectively, so F intake by infants from IMFs depends on the F content of the added water. 14 F can cause variety of diseases. 7,10 For province number 18 (Bushehr) the F intake from milk powder formula made with tap water was g/kg bw/day while for the other 29 provinces in Iran, the range of F intake g/kg bw/day (Table 3). Thus the infants in all 30 regions in Iran are exposed to the risk of most of the adverse effects of F such as stage II skeletal fluorosis, impaired glucose metabolism, impaired thyroid function, and moderate dental fluorosis. In addition, the infants in province number 18 are exposed additional adverse effects such as neurotoxicity and severe dental fluorosis. Table 3 showed the estimated F intakes from powdered milk formula when made up with tap water. When other F sources are included, the total F intake will be higher. It has been found that to be in on the safe side of the risk of fluorosis or dental caries in the future, the estimated mean daily F intake should be at or below 50 µg F/kg bw/day for nearly all time points through the first 48 months of life. 15 Various researchers 4,16,17 have estimated that F intakes of µg/kg bw/day are associated with development of enamel fluorosis of the permanent teeth. EPA s reference dose of 60 µg F/kg bw/day is not protective for most of these health endpoints. In order to be safe for all members of the population, F intakes must be kept below the lowest no-effect levels, when all sources of F intake are included, and with an adequate margin of safety. It

5 363 Estimation of fluoride intake by Iranian powdered milk-fed infants 363 is recommended in areas with high concentrations of fluoride in water, F should be removed from drinking water. 18 ACKNOWLEDGEMENTS The authors gratefully appreciate the financial support of Center for Air Pollution Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran, for this work which made the study possible. REFERENCES 1 Nouri J, Mahvi AH, Babaei A, Ahmadpour E. Regional pattern distribution of groundwater fluoride in the Shush aquifer of Khuzestan County, Iran. Fluoride 2006;39(4): Mahvi AH, Zazoli MA, Younecian M, Nicpour B, Babapour A. Survey of fluoride concentration in drinking water sources and prevalence of DMFT in the 12 years old students in Behshar City. Journal of Medical Sciences 2006;6(4): Dobaradaran S, Mahvi AH, Dehdashti S, Abadi DRV. Drinking water fluoride and child dental caries in Dashtestan, Iran. Fluoride 2008;41(3): Forsrnan B. Early supply of fluoride and enamel fluorosis. Scand J Dent Res 1977;85: Walton JL, Messer LB. Dental caries and fluorosis in breast-fed and bottle-fed children. Caries Res 1981;15: Ericsson Y. State of fluoride in milk and its absorption and retention when administration in milk: investigations with radio-active fluorine. Acta Odont Scand 1958;16: Limeback H, Thiessen KM, Isaacson RL, Hirzy W. The EPA MCLG for fluoride in drinking water: new recommendations. [presentation to the Society of Toxicology 2007 Annual Meeting]. Toxicological Sciences 2007;96 (1): Dobaradaran S, Mahvi AH, Dehdashti S. Fluoride content of bottled drinking water available in Iran. Fluoride 2008;41(1): Mahvi AH, Zazoli MA, Younecian M, Esfandiari Y. Fluoride content of Iranian black tea and tea liquor. Fluoride 2006;39(4): Mesdaghinia A, Azam Vaghefi K, Montazeri A, Mohebbi MR, Saeedi R. Monitoring of fluoride in groundwater resources of Iran. Bulletin of Environmental Contamination and Toxicology 2010;84(4): Mahvi A H, Ghanbarian Maryam, Ghanbarian Marjan, Khosravi A, Ghanbarian Masoud. Determination of fluoride concentration of powder milk in Iran British Journal of nutrition 2012;107: U.S. Environmental Protection Agency Office of Water and Office of Science and Technology. Estimated per capita water ingestion and body weight in the United States an update: baed on data collected by the United States Department of Agriculture s and 1998 continuing survey of food intakes by individuals. EPA-822-R Washington, DC: U.S. Environmental Protection Agency Office of Water and Office of Science and Technology; October Available from: advisories/drinking/upload/2005_05_06_criteria_drinking_percapita_2004.pdf 13 NRC (National Research Council). Fluoride in drinking water: a scientific review of EPA s standards. Washington, DC: The National Academies Press; 2006 Available at: Nohno K, Zohoori FV, Maguire A. Fluoride intake of Japanese infants from infant milk formula. Caries Res 2011;45: (doi: / ). 15 Warren JJ, Levy SM, Broffitt B, Cavanaugh JE, Kanellis MJ, Weber-Gasparoni K. Consideration on optimal fluoride intake using dental fluorosis and dental caries outcomes: a longitudinal study. J Public Health Dent 2009;69(20:111-5 [abstract in Fluoride 2010;43(4):253-4]. 16 Toth K. Fluoride ingestion related to body weight [abstract]. Caries Res 1975; 9, Baelum V, Fejerskov 0, Manji F, Larsen MJ. Daily dose of fluoride and dental fluorosis. Danish Dent J 1987;91: Boldaji MR, Mahvi AH, Dobaradaran S, Hosseini SS. Evaluating the effectiveness of a hybrid sorbent resin in removing fluoride from water. International Journal of Environmental Science and Technology, 2009;6: Copyright 2014 The International Society for Fluoride Research Inc Editorial Office: 727 Brighton Road, Ocean View, Dunedin 9035, New Zealand.