Skeletal fluorosis in a resettled refugee from Kakuma refugee camp

“I suspected some contamination of the water of the much-frequented street pump in Broad Street, near the end of Cambridge Street”, said John Snow, about the contaminated water pump of the cholera outbreak of 1854, in London, UK.1Parkes EA Mode of communication of cholera by John Snow, MD: second edition – London, 1855, pp 162.Int J Epidemiol. 2013; 42: 1543-1552Crossref PubMed Scopus (10) Google Scholar In September, 2015, a Somalian man aged 46 years presented to a refugee clinic within 1 month of resettlement to Canada. From 2009 to 2015, this patient had lived in the Kakuma refugee camp (Rift Valley Province, Kenya), which houses 184 966 inhabitants.2UNHCRKakuma refugee camp: camp population by country of origin, sex and age group.https://reliefweb.int/sites/reliefweb.int/files/resources/KakumaCampPopulation_20160111.pdfDate: 2016Date accessed: November 30, 2017Google Scholar, 3Bauman P Ernst E Woods L Surface geophysical exploration for groundwater at the Kakuma refugee camp in Turkana County, Kenya.CSEG Recorder. 2017; 42: 36-43Google Scholar He had chronic, debilitating, diffuse axial bone pain, insidiously worsening over the previous 5 years, beginning with lumbar and hip pain. In the year before presentation, he was no longer able to rise from a chair alone and had an antalgic, shuffling gait with pronounced kyphosis. His sclerae were white and dentition poor. Spinal and hip mobility was severely limited in all directions, and point tenderness was present throughout the lumbar spine, sacro-iliac joints, and chest wall. Clinical investigation revealed elevated serum alkaline phosphatase with normal serum calcium, albumin, and 25-hydroxyvitamin D. All investigations are summarised in the appendix. Pelvic radiograph, CT scan, and a whole body technetium-labelled bisphosphonate bone scan revealed diffuse osteosclerosis with ligamentous calcifications. Bone densitometry (Hologic Discovery W; Marlborough, MA, USA) showed lumbar spine and femoral neck Z scores of 8·7 and 3·7, respectively. The extensive osteosclerosis led to measurement of serum and urine fluoride; both were within the normal range for someone drinking municipally fluoridated water (appendix). In October, 2016, a tetracycline-labelled iliac crest open bone biopsy for histomorphometry revealed a combination of osteosclerosis with severe low turnover osteomalacia, suggesting skeletal fluorosis (appendix). Additional bone biopsy specimen sections were ashed for direct bone fluoride content measurement, revealing 6·73 g/kg fluoride ash weight (normal range 0·5–1·2 g/kg), confirming severe skeletal fluorosis. In July 2016, 15 water wells supplying drinking water for Kakuma's residents had fluoride concentrations of 1·5–8·4 mg/L.3Bauman P Ernst E Woods L Surface geophysical exploration for groundwater at the Kakuma refugee camp in Turkana County, Kenya.CSEG Recorder. 2017; 42: 36-43Google Scholar WHO drinking water guidelines4Fawell JK Bailey K Chilton J et al.Fluoride in drinking-water. IWA Publishing on behalf of the World Health Organization, London2006Google Scholar recommend fluoride concentrations of 1·5 mg/L or less. Our patient lived in a camp section exclusively supplied by a single well (borehole 5; figure),5Adapted from UN map: Planning and Information Units Sources: UNHCR/NCCK – Kakuma, Datum: WGS 1984, Projection: UTM ZONE 37S, January, 2013.Google Scholar, 6TUBS“Kenya, administrative divisions - de – monochrome”. Adapted by GE Fabreau to change language and merge with map of Kakuma refugee camp.https://commons.wikimedia.org/wiki/File:Kenya,_administrative_divisions_-_de_-_ monochrome.svg. Licenced under CC BY-SA 3.0Date accessed: November 21, 2018Google Scholar which consistently contained high fluoride concentrations between 2014 and 2016 (8·4 mg/L in July, 2016).3Bauman P Ernst E Woods L Surface geophysical exploration for groundwater at the Kakuma refugee camp in Turkana County, Kenya.CSEG Recorder. 2017; 42: 36-43Google Scholar Symptomatic skeletal fluorosis from either environmental or toxic exposure has been described globally, with the highest reported burden in China and India.4Fawell JK Bailey K Chilton J et al.Fluoride in drinking-water. IWA Publishing on behalf of the World Health Organization, London2006Google Scholar, 7Edmunds W Smedley P Fluoride in natural waters.in: Essentials of medical geology: impacts of the natural environment on public health. Elsevier Academic Press, Burlington2005: 301-330Google Scholar There, the reported prevalence of skeletal fluorosis among populations exposed to drinking water with high fluoride concentrations (>4·8 mg/L) ranged from 26% to 63%.4Fawell JK Bailey K Chilton J et al.Fluoride in drinking-water. IWA Publishing on behalf of the World Health Organization, London2006Google Scholar Other potential toxic exposures, most often reported in modern cases, include consuming teas containing the fluoride-concentrating tea plant Camellia sinensis.8Kurland ES Schulman RC Zerwekh JE et al.Recovery from skeletal fluorosis (an enigmatic, American case).J Bone Miner Res. 2007; 22: 163-170Crossref PubMed Scopus (47) Google Scholar, 9Izuora K Twombly JG Whitford GM Demertzis J Pacifici R Whyte MP Skeletal fluorosis from brewed tea.J Clin Endocrinol Metab. 2011; 96: 2318-2324Crossref PubMed Scopus (44) Google Scholar Fluoride is a naturally occurring element in all natural waters and is associated with geological environments containing volcanic rocks.3Bauman P Ernst E Woods L Surface geophysical exploration for groundwater at the Kakuma refugee camp in Turkana County, Kenya.CSEG Recorder. 2017; 42: 36-43Google Scholar, 4Fawell JK Bailey K Chilton J et al.Fluoride in drinking-water. IWA Publishing on behalf of the World Health Organization, London2006Google Scholar, 7Edmunds W Smedley P Fluoride in natural waters.in: Essentials of medical geology: impacts of the natural environment on public health. Elsevier Academic Press, Burlington2005: 301-330Google Scholar The east African Rift Valley, where the Kakuma refugee camp is located, geologically comprises volcanic rock aquifers with naturally high fluoride concentration groundwater.3Bauman P Ernst E Woods L Surface geophysical exploration for groundwater at the Kakuma refugee camp in Turkana County, Kenya.CSEG Recorder. 2017; 42: 36-43Google Scholar, 4Fawell JK Bailey K Chilton J et al.Fluoride in drinking-water. IWA Publishing on behalf of the World Health Organization, London2006Google Scholar, 7Edmunds W Smedley P Fluoride in natural waters.in: Essentials of medical geology: impacts of the natural environment on public health. Elsevier Academic Press, Burlington2005: 301-330Google Scholar Dental fluorosis has been reported in this region, but to our knowledge, no cases of severe skeletal fluorosis have been reported in inhabitants of Kakuma refugee camp.4Fawell JK Bailey K Chilton J et al.Fluoride in drinking-water. IWA Publishing on behalf of the World Health Organization, London2006Google Scholar, 7Edmunds W Smedley P Fluoride in natural waters.in: Essentials of medical geology: impacts of the natural environment on public health. Elsevier Academic Press, Burlington2005: 301-330Google Scholar Clinical diagnosis of fluorosis is challenging and requires multidisciplinary collaboration (appendix). Clinicians in migrant-receiving nations often lack awareness of, and available diagnostic tests for, fluorosis, which probably leads to under-reporting. No treatment exists for fluorosis other than halting exposure, with symptom resolution as fluoride mobilises slowly from bone.8Kurland ES Schulman RC Zerwekh JE et al.Recovery from skeletal fluorosis (an enigmatic, American case).J Bone Miner Res. 2007; 22: 163-170Crossref PubMed Scopus (47) Google Scholar The patient's symptoms markedly improved with reduced pain and with improved mobility and daily activity over the subsequent 9 months after diagnosis, nearly 2 years after fluoride exposure cessation. Here we have presented a single case of severe skeletal fluorosis; however, entire populations, such as Kakuma's approximately 185 000 residents, who depend on naturally occurring fluoride-contaminated well water, might be affected en masse.2UNHCRKakuma refugee camp: camp population by country of origin, sex and age group.https://reliefweb.int/sites/reliefweb.int/files/resources/KakumaCampPopulation_20160111.pdfDate: 2016Date accessed: November 30, 2017Google Scholar, 3Bauman P Ernst E Woods L Surface geophysical exploration for groundwater at the Kakuma refugee camp in Turkana County, Kenya.CSEG Recorder. 2017; 42: 36-43Google Scholar, 4Fawell JK Bailey K Chilton J et al.Fluoride in drinking-water. IWA Publishing on behalf of the World Health Organization, London2006Google Scholar Many countries with naturally high water-fluoride concentrations host large refugee populations, including Ethiopia, Iraq, Kenya, South Sudan, Syria, and Turkey.4Fawell JK Bailey K Chilton J et al.Fluoride in drinking-water. IWA Publishing on behalf of the World Health Organization, London2006Google Scholar, 7Edmunds W Smedley P Fluoride in natural waters.in: Essentials of medical geology: impacts of the natural environment on public health. Elsevier Academic Press, Burlington2005: 301-330Google Scholar, 10UN High Commissioner for RefugeesGlobal trends: forced displacement in 2016.http://www.unhcr.org/globaltrends2016/Date: 2017Date accessed: August 17, 2017Google Scholar Displaced populations who depend on well water in these areas can be at particular risk, especially children with developing skeletons and lower volumes of distribution. We relayed our clinical information to the Kakuma refugee camp UNHCR Water, Sanitation, and Hygiene officers, who subsequently successfully drilled three new water wells with safe fluoride concentrations (<1·5 mg/L) for the first time.3Bauman P Ernst E Woods L Surface geophysical exploration for groundwater at the Kakuma refugee camp in Turkana County, Kenya.CSEG Recorder. 2017; 42: 36-43Google Scholar, 4Fawell JK Bailey K Chilton J et al.Fluoride in drinking-water. IWA Publishing on behalf of the World Health Organization, London2006Google Scholar Boreholes 13, 14, and 15 produced well water with fluoride concentrations of 1·1 mg/L, 0·9 mg/L, and 0·6 mg/L, respectively (personal communication; Paul Bauman, Advisian, Worley Parsons Group). The prevalence of skeletal fluorosis in Kakuma could be under-reported. As the numbers of forcefully displaced persons rise globally,10UN High Commissioner for RefugeesGlobal trends: forced displacement in 2016.http://www.unhcr.org/globaltrends2016/Date: 2017Date accessed: August 17, 2017Google Scholar clinicians in refugee host nations should maintain a broad approach to newcomers' health issues and consider potentially important environmental exposures in addition to infectious pathogens. Ultimately, safe drinking water endures as a fundamental principle of human health. We declare no competing interests. There was no direct funding source for this study. Academic support for GEF and GAK is provided by the Cumming School of Medicine, O'Brien Institute for Public Health, and the W21C Research and Innovation Centre at the University of Calgary and Alberta Health Services. We thank the health-care providers, staff, and patients at the Mosaic Refugee Health Clinic and the institutional support provided by the O'Brien Institute for Public Health and the W21C Research and Innovation Centre at the University of Calgary Cumming School of Medicine— in particular, Garielle Brown for her efforts, without which this report would not be possible. The patient provided written consent for use and disclosure of all relevant clinical information presented. Download .pdf (.57 MB) Help with pdf files Supplementary appendix

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