1
|
Foat A, Stevens C, George G, Massawe J, Mhina A, Gray WK, Mmbaga BT, Rwakatema DS, Sallis P, Jarvis H, Haule I, Benedict D, Walker R. Prevalence of Skeletal Fluorosis in Northern Tanzania: A Follow-Up Study. GLOBAL HEALTH, SCIENCE AND PRACTICE 2023; 11:e2200342. [PMID: 38135514 PMCID: PMC10749641 DOI: 10.9745/ghsp-d-22-00342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 11/19/2023] [Indexed: 12/24/2023]
Abstract
OBJECTIVES Skeletal fluorosis is a metabolic bone disease caused by excessive exposure to fluoride, predominantly through contamination of drinking water. This study aimed to identify all cases of skeletal fluorosis in Tindigani village situated in Northern Tanzania. This was done following changes in drinking water sources after a previous prevalence study in 2009 in this population. METHODS In a door-to-door cross-sectional study of Tindigani village, a sample of residents was assessed for skeletal fluorosis and dental fluorosis. Diagnosis of skeletal fluorosis was based on pre-defined angles of deformity of the lower limbs. Dental fluorosis was diagnosed and graded using the Thylstrup and Fejerskov Index. Samples from current drinking water sources underwent fluoride analysis. RESULTS Tindigani village had a population of 1,944 individuals. Of the 1,532 individuals who were screened, 45 had skeletal fluorosis, giving a prevalence of 3.3% (95% CI=2.4, 4.3). Dental fluorosis was present in 82.5% of those examined (95% CI=79.8, 85.3). Dental fluorosis was present in all individuals with skeletal fluorosis and at higher grades than in the rest of the population. Drinking water samples were collected from 28 sources. These included piped, surface, well, and borehole water sources. Fluoride concentrations ranged from 0.45-38.59 mg/L of fluoride. CONCLUSIONS Skeletal fluorosis is an ongoing but preventable health problem in the current population. The delivery of sustainable low fluoride piped water to this community would be of clear health benefit. This has been addressed at a local level.
Collapse
Affiliation(s)
- Anna Foat
- Faculty of Medical Sciences, Masters by Research, Newcastle University, Newcastle Upon Tyne, United Kingdom.
| | - Claire Stevens
- Faculty of Medical Sciences, Masters by Research, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Grace George
- Faculty of Medical Sciences, Masters by Research, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - John Massawe
- Hai District Hospital, Boma Ng'ombe, United Republic of Tanzania
| | - Ally Mhina
- Hai District Hospital, Boma Ng'ombe, United Republic of Tanzania
| | - William K Gray
- Northumbria Healthcare NHS Foundation Trust, North Tyneside General Hospital, North Shields, United Kingdom
| | - Blandina T Mmbaga
- Kilimanjaro Clinical Research Institute, Moshi, United Republic of Tanzania
| | | | - Paul Sallis
- School of Engineering, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Helen Jarvis
- Population Health Science Institute, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Irene Haule
- Hai District Hospital, Boma Ng'ombe, United Republic of Tanzania
| | - Daniel Benedict
- Hai District Water Authority, Boma Ng'ombe, United Republic of Tanzania
| | - Richard Walker
- Northumbria Healthcare NHS Foundation Trust, North Tyneside General Hospital, North Shields, United Kingdom
- Population Health Science Institute, Newcastle University, Newcastle Upon Tyne, United Kingdom
| |
Collapse
|
2
|
Veneri F, Iamandii I, Vinceti M, Birnbaum LS, Generali L, Consolo U, Filippini T. Fluoride Exposure and Skeletal Fluorosis: a Systematic Review and Dose-response Meta-analysis. Curr Environ Health Rep 2023; 10:417-441. [PMID: 37861949 DOI: 10.1007/s40572-023-00412-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2023] [Indexed: 10/21/2023]
Abstract
PURPOSE OF REVIEW We performed a systematic review and meta-analysis on the relation between fluoride exposure and skeletal fluorosis (SF) using a novel statistical methodology for dose-response modeling. RECENT FINDINGS Skeletal fluorosis, a major health issue that is endemic in some regions, affects millions of people worldwide. However, data regarding the dose-response relation between fluoride exposure and SF are limited and outdated. We included twenty-three studies in the meta-analysis. When comparing the highest versus the lowest fluoride category, the summary risk ratio (RR) for SF prevalence was 2.05 (95% CI 1.60; 2.64), with a value of 2.73 (95% CI 1.92; 3.90) for drinking water and 1.40 (95% CI 0.90; 2.17) for urinary fluoride. The RR by the risk of bias (RoB) was 2.37 (95% CI 1.56; 3.58) and 1.78 (95% CI 1.34; 2.36) for moderate and high RoB studies, respectively. The dose-response curve based on a one-stage cubic spline regression model showed an almost linear positive relation between exposure and SF occurrence starting from relatively low concentrations up to 5 mg/L and 2.5 mg/L, respectively, for water and urinary fluoride, with no substantial increase above this threshold. The RR for developing moderate-severe forms increases at 5.00 mg/L and 2.5 mg/L of water and urinary fluoride, respectively. Better-quality studies are needed to confirm these results, but greater attention should be given to water fluoride levels to prevent SF, in addition to the other potential adverse effects of fluoride exposure.
Collapse
Affiliation(s)
- Federica Veneri
- Department of Surgery, Medicine, Dentistry and Morphological Sciences with Transplant Surgery, Oncology and Regenerative Medicine Relevance (CHIMOMO), Unit of Dentistry & Oral-Maxillo-Facial Surgery - University of Modena and Reggio Emilia, 41124, Modena, Italy
- PhD Program in Clinical and Experimental Medicine, Department of Biomedical, Metabolic and Neural Sciences - University of Modena and Reggio Emilia, 41124, Modena, Italy
| | - Inga Iamandii
- Environmental, Genetic and Nutritional Epidemiology Research Center (CREAGEN), Department of Biomedical, Metabolic and Neural Sciences, Medical School - University of Modena and Reggio Emilia, 41124, Modena, Italy
| | - Marco Vinceti
- Environmental, Genetic and Nutritional Epidemiology Research Center (CREAGEN), Department of Biomedical, Metabolic and Neural Sciences, Medical School - University of Modena and Reggio Emilia, 41124, Modena, Italy.
- Department of Epidemiology, Boston University School of Public Health, Boston, MA, 02215, USA.
| | - Linda S Birnbaum
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
| | - Luigi Generali
- Department of Surgery, Medicine, Dentistry and Morphological Sciences with Transplant Surgery, Oncology and Regenerative Medicine Relevance (CHIMOMO), Unit of Dentistry & Oral-Maxillo-Facial Surgery - University of Modena and Reggio Emilia, 41124, Modena, Italy
| | - Ugo Consolo
- Department of Surgery, Medicine, Dentistry and Morphological Sciences with Transplant Surgery, Oncology and Regenerative Medicine Relevance (CHIMOMO), Unit of Dentistry & Oral-Maxillo-Facial Surgery - University of Modena and Reggio Emilia, 41124, Modena, Italy
| | - Tommaso Filippini
- Environmental, Genetic and Nutritional Epidemiology Research Center (CREAGEN), Department of Biomedical, Metabolic and Neural Sciences, Medical School - University of Modena and Reggio Emilia, 41124, Modena, Italy
- School of Public Health, University of California Berkeley, Berkeley, CA, 94720, USA
| |
Collapse
|
3
|
Nelima D, Wambu EW, Kituyi JL. Fluoride distribution in selected foodstuffs from Nakuru County, Kenya, and the risk factors for its human overexposure. Sci Rep 2023; 13:15295. [PMID: 37714918 PMCID: PMC10504336 DOI: 10.1038/s41598-023-41601-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 08/29/2023] [Indexed: 09/17/2023] Open
Abstract
Critical data on the impacts of fluoride (F) in food systems along the Eastern Africa Rift Valley System (EARS) is needed for public health risk assessment and for the development of strategies for ameliorating its deleterious effects among the affected communities. Long-term F overexposure causes dental and skeletal fluorosis, and leads to neurotoxicity, which impacts several important body functions. Investigating F exposure pathways is of essence to inform and safeguard public health of the affected communities. The current study assessed the F levels in potatoes (Solanum tuberosum L.), beans (Phaseolus vulgaris L.) and garden peas (Possum sativa) from Nakuru County, Kenya, by potentiometric analysis using F ion-selective electrodes. It then evaluated the risk factors for excessive human exposure to F through contaminated foodstuffs. The mean F levels in the potatoes (8.50 ± 4.70 mg/kg), beans (8.02 ± 4.12 mg/kg) and peas (4.99 ± 1.25 mg/kg) exceeded recommended dietary allowances (RDA) level of 4 mg/kg endorsed by US Institute of Medicine for the different categories of people. The F distribution trends in beans and potatoes reflected the environmental patterns of F contamination of the study area but the spatial extent Fin the peas indicated existence of partial resistance of the pea plants to environmental F uptake. The results indicated that both the beans and the potatoes were more liable to accumulating greater amounts of F from the environment than garden peas and that all the three foodstuffs contained high F levels that posed greater risk of F overexposure and its deleterious impacts among the young children, male populations, and in people of greater body weight and high physical activity levels.
Collapse
Affiliation(s)
- Delphine Nelima
- Department of Chemistry, School of Science, University of Eldoret, P.O. BOX, Eldoret, 1125-30100, Kenya
| | - Enos W Wambu
- Department of Chemistry, School of Science, University of Eldoret, P.O. BOX, Eldoret, 1125-30100, Kenya.
| | - John L Kituyi
- Department of Chemistry, School of Science, University of Eldoret, P.O. BOX, Eldoret, 1125-30100, Kenya
| |
Collapse
|
4
|
Renewable energy powered membrane technology: System resilience under solar irradiance fluctuations during the treatment of fluoride-rich natural waters by different nanofiltration/reverse osmosis membranes. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2020.118452] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
5
|
Addison MJ, Rivett MO, Robinson H, Fraser A, Miller AM, Phiri P, Mleta P, Kalin RM. Fluoride occurrence in the lower East African Rift System, Southern Malawi. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 712:136260. [PMID: 31945540 DOI: 10.1016/j.scitotenv.2019.136260] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 12/18/2019] [Accepted: 12/19/2019] [Indexed: 06/10/2023]
Abstract
Countries located on the East African Rift System (EARS) are vulnerable to fluoride in their groundwater; a vulnerability for the developing country of Malawi at the southern rift periphery that is not well characterised. Groundwater fluoride occurrence in Malawi is documented here to better understand and manage fluoride risks posed. Available literature and Gov't of Malawi archive fluoride data spanning some fifty years have been collated and augmented by our own 2016-18 surveys of groundwater quality in Southern Malawi, targeting deep-sourced springs. In total, fluoride data for 1365 borehole, spring and hot spring samples were assembled. Statistically, 83% of samples were below the 1.5 mg/l WHO limit, concentrations in the 1.5-6 mg/l range between former (pre-1993) and current WHO guidelines at 14%, and those with fluoride above the current Malawi (former WHO) 6 mg/l guideline, at 3%. A lower occurrence than in other zones of the EARS, but indicative of a need for a Malawi Gov't management policy revision and associated management strategies endorsed by several documented incidences of dental fluorosis in proximity to high fluoride groundwater. Increased fluoride is related to increased groundwater temperatures signifying the importance of geothermal groundwater provenance. Temperature data may indeed be used as a proxy indicator of fluoride risk; samples with a temperature >32 °C, contained >6 mg/l fluoride. Structural geological controls appear to allow deep geothermal groundwaters to come to the near surface, as evidenced by increased fluoride in springs and boreholes close to faulted areas. Hydrochemical evaluation shows that fluoride concentrations are influenced by fluorite equilibration and sensitivity to calcium and pH. Recommendations are made to further document the occurrence of fluoride and enhance management of risks due to fluoride in drinking water in Malawi. With fluoride as a key indicator within Sustainable Development Goal number 6, the current Malawi standard and waters with concentration between 1.5 and 6 mg/l will come under increased scrutiny and pose a key challenge to assessment and management efforts.
Collapse
Affiliation(s)
- Marc J Addison
- Department of Civil & Environmental Engineering, University of Strathclyde, Glasgow, Scotland, G1 1XJ.
| | - Michael O Rivett
- Department of Civil & Environmental Engineering, University of Strathclyde, Glasgow, Scotland, G1 1XJ
| | - Helen Robinson
- Department of Civil & Environmental Engineering, University of Strathclyde, Glasgow, Scotland, G1 1XJ
| | - Aimee Fraser
- Department of Civil & Environmental Engineering, University of Strathclyde, Glasgow, Scotland, G1 1XJ
| | - Alexandra M Miller
- Department of Civil & Environmental Engineering, University of Strathclyde, Glasgow, Scotland, G1 1XJ
| | - Peaches Phiri
- The Ministry of Agriculture, Irrigation and Water Development, Regional Irrigation and Water Development Office, Lilongwe Headquarters, Private Bag 390, Lilongwe, Malawi
| | - Prince Mleta
- The Ministry of Agriculture, Irrigation and Water Development, Regional Irrigation and Water Development Office, Lilongwe Headquarters, Private Bag 390, Lilongwe, Malawi
| | - Robert M Kalin
- Department of Civil & Environmental Engineering, University of Strathclyde, Glasgow, Scotland, G1 1XJ
| |
Collapse
|
6
|
Shen J, Jeihanipour A, Richards BS, Schäfer AI. Renewable energy powered membrane technology: Experimental investigation of system performance with variable module size and fluctuating energy. Sep Purif Technol 2019. [DOI: 10.1016/j.seppur.2019.03.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
7
|
Ibiyemi O, Zohoori FV, Valentine RA, Maguire A. Fluoride intake and urinary fluoride excretion in 4- and 8-year-old children living in urban and rural areas of Southwest Nigeria. Community Dent Oral Epidemiol 2018; 46:482-491. [PMID: 29971814 DOI: 10.1111/cdoe.12396] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 05/30/2018] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To estimate and compare total daily fluoride intake (TDFI), daily urinary fluoride excretion (DUFE), daily fluoride retention (DFR), fractional urinary fluoride excretion (FUFE) and fractional fluoride retention (FFR) in 4- and 8 year-old Nigerians and explore associations between these outcomes to improve understanding of fluoride metabolism. METHODS Using a cross-sectional observational study, 72 four-year-olds and 72 eight-year-olds were recruited from nursery and primary schools (respectively) in lower and higher water F areas of urban and rural localities in Oyo State, southwest Nigeria. TDFI from diet and toothpaste ingestion was assessed using a validated Food Frequency Questionnaire and visual scale of toothpaste used during toothbrushing. DUFE was measured by collecting a 24-hour urine sample, FUFE estimated as the ratio between DUFE and TDFI, DFR estimated as TDFI-TDFE (where TDFE = DUFE + estimated faecal F excretion (ie TDFI × 10%), and FFR was estimated as [(TDFI-DFR)/TDFI] × 100. Data were analysed using ANOVA with post hoc tests and Student's t tests and strengths of associations between key variables measured. RESULTS Mean (SD) TDFI, DUFE, DFR, FUFE and FFR were 0.137 (0.169) mg/kg bw/d, 0.032 (0.027) mg/kg bw/d, 0.091 (0.147) mg/kg bw/d, 44% (44%) and 46% (44%), respectively, for 4-year-olds. Corresponding values for 8-year-olds (n = 63) were 0.106 (0.130) mg/kg bw/d, 0.022 (0.017) mg/kg bw/d, 0.073 (0.107) mg/kg bw/d, 36% (30%) and 54% (30%), respectively. Dietary contribution to TDFI was 79% and 75% (respectively), for 4- and 8-year-olds. Mean (SD) TDFI from toothpaste ingestion was 0.021 (0.013) mg/kg bw/d in 4-year-olds, 0.014 (0.010) mg/kg bw/d in 8-year-olds (P = .002) but with no differences between areas. Differences in dietary F intake determined the main differences in F exposure between areas. The positive correlation between TDFI and DUFE was weak for 4-year-olds (r = +.29) and strong for 8-year-olds (r = +.64). A strong positive correlation was observed between TDFI and DFR for both age groups: (r) = +.98 for 4-year-olds and (r) = +.99 for 8-year-olds. CONCLUSION Fluoride intake in these 4- and 8-year-old Nigerians was much higher than the "optimal range" of 0.05-0.07 mg/kg bw/d in rural, higher F water areas, with diet as the main contributor. F retention was similar in both age groups, with almost half of TDFI retained in the body. In terms of risk vs benefit for fluorosis and dental caries, this finding should be considered when mitigating against excessive fluoride exposure and planning F-based prevention.
Collapse
Affiliation(s)
- O Ibiyemi
- Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne, UK.,Institute of Health and Society, Newcastle University, Newcastle upon Tyne, UK
| | - F V Zohoori
- School of Health and Social Care, Teesside University, Middlesbrough, UK
| | - R A Valentine
- Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - A Maguire
- Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne, UK
| |
Collapse
|
8
|
Shen J, Richards BS, Schäfer AI. Renewable energy powered membrane technology: Case study of St. Dorcas borehole in Tanzania demonstrating fluoride removal via nanofiltration/reverse osmosis. Sep Purif Technol 2016. [DOI: 10.1016/j.seppur.2016.06.042] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
9
|
Jarvis HG, Heslop P, Kisima J, Gray WK, Ndossi G, Maguire A, Walker RW. Prevalence and aetiology of juvenile skeletal fluorosis in the south-west of the Hai district, Tanzania--a community-based prevalence and case-control study. Trop Med Int Health 2012. [PMID: 23198699 DOI: 10.1111/tmi.12027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Fluorosis is endemic throughout the East African Rift valley, including parts of Tanzania. The aim of the study was to identify all cases of deforming juvenile skeletal fluorosis (JSF) in a northern Tanzanian village and to document the extent of dental fluorosis (DF). METHODS Door-to-door prevalence survey of all residents of the village. Residents were assessed for the presence of DF and JSF. Those with JSF and randomly selected controls from the same age range were further assessed for possible JSF risk factors. RESULTS The village had a population of 1435. DF was endemic within the population, being present in 911 (75.5%; 95% CI, 73.0-77.9) of dentate individuals who were examined (n = 1207). JSF was present in 56 of 1263 people examined, giving a prevalence of 4.4% (95% CI, 3.3-5.6) and was more common in males. Low body mass index, drinking predominantly well water 3 years previously, not being weaned on bananas, the use of fluoride salts in cooking during childhood and drinking more cups of tea per day were independent predictors of JSF. CONCLUSIONS Juvenile skeletal fluorosis is a common and preventable public health problem. Providing clean, low-fluoride, piped water to affected communities is of obvious health benefit.
Collapse
Affiliation(s)
- Helen G Jarvis
- Northumbria Healthcare NHS Foundation Trust, North Tyneside General Hospital, North Shields, UK.
| | | | | | | | | | | | | |
Collapse
|