Health risk assessment of fluoride

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Health risk assessment of fluoride in drinking water: a case study from
Arcahaie and Cabaret (Haiti).
Cajouste Tony Jean-Pierre, Yanick Simon, Tatiana Charles, Islande Léandre, Evens Emmanuel
Laboratoire Santé-Environnement, Université Quisqueya, 218 Avenue Jean-Paul II, Haut de Turgeau, Port-au-Prince, Haïti.

ABSTRACT
Fluoride is an essential element in the human body whose drinking water is often the main source of supply. It is reported in the literature that prolonged excessive intake of fluoride has been associated with fluorosis, a
degenerative and progressive, which adversely affects several organs. The World Health Organization (WHO) sets the threshold value of fluoride in drinking water at 1.5 mg/L Previous studies have revealed fluoride concentrations
above 1.5 mg/L in groundwater resources in alluvial aquifers of Cabaret and Archahaie. The aim of this study was to assess human health risks generated by exposure to high fluoride concentrations in drinking water from these
aquifers. Major risks of fluorosis, particularly for children, were characterised. In order to assess and control the prevalence of fluorosis and / or dental caries, it seems important in the future to develop a monitoring system on the
groundwater quality from the different geological formation of that region, associated with epidemiological studies.

INTRODUCTION
Fluorine participates in the formation of bones and teeth and helps to their solidification. In drinking
water, one of the major sources of fluoride supply in the human body, WHO ranges the threshold
value between 1 to 1.5 mg/L. Indeed, concentrations lower than 1 mg/L can cause dental caries,
reduction of mineralization of bones and teeth. In contrast, a concentration greater than 1.5 mg/L is
the cause of the increased prevalence of fluorosis in both endemic and non-endemic areas.

In Haiti, concentrations ranging from 0-2 mg / L were obtained on samples from water resources of the hydrographic region
“Center-South”. Samples from alluvial aquifers of Cabaret and Arcahaie had fluoride concentrations above 1.5 mg/L .
Consumers of water from these aquifers are exposed to chronic hazards of dental fluorosis. Fluoride’s exposure is a major
public health problem particularly for children. Indeed, intake of high water fluoride concentration during child’s growth and
development stages has been associated with mental and physical problems.

OBJECTIVE
The objective of this study is to assess the health hazards of geological origin of fluoride in drinking water to Archahaie and cabaret (Haiti).

MATERIAL AND METHODS

Map of Centre-Sud hydrographical region of Haiti

Concentration level of fluoride

Samples point in the selected area

RESULTS
Table 1: Variations of fluoride concentrations in water samples from the 5 sampling points
Sampling points

Unit

Means

Minisma

Maxima

SD

N

Table 2: Calculated risks for fluoride in the selected wells
Sampling
points

MDI (mg/kg/day)
Adults
Infants
Infants
5–14
0–4 years
years

ADI
mg/kg/day

Risks (=MDI/ADI)
Adults
Infants
Infants
5–14
0–4
years
years

Luly

mg\L

1.58

1.53

1.64

0.05

5

Williamson

mg\L

1.69

1.60

1.85

0.10

5

Sources Matelas

mg\L

1.20

1.17

1.24

0.03

5

Luly
Williamson

7.23
8.16

25.30
28.54

37.95
42.81

0.06
0.06

120
136

422
476

633
714

Titanyen

Mg\L

1.71

1.67

1.75

0.03

5

Titanyen

7.71

27.00

40.50

0.06

129

450

675

Lafiteau

Mg\L

2.01

1.92

2.10

0.07

5

Lafiteau

9.26

32.40

48.60

0.06

154

540

810

CONCLUSION
The aims of this study was to assess human health risks generated by chronic exposure to high fluoride concentration in drinking water from alluvial aquifers of Cabaret and Acahaie .Risk quotients
ranged from 120 to 154 were estimated for adults living in four localities(Luly, Williamson,Titanyen and Lafiteau), while risk quotients for infants of 5- 14 years ranged from 422 to 540.For infants 0-4
years the calculated risk quotients were ranged from 633 to 810.These risks were very much limit of 1.These results have been obtained on 5 samples only from retained localities.It is necessary
to characterise fluoride with a larger number of water samples in order to confirm these initial results .In the future ,it would be intereting to reinforce theseestimations by carrying out epidemiological
studies on the exposed population.

References
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htpp://www.atsdr.cdc.gov/toxpro2.html.
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