Correlation of Water Fluoride with Body Fluids, Dental Fluorosis and FT4, FT3 –TSH Disruption among Children in an Endemic Fluorosis area in Pakistan

Abstract

In the present study 134 children were studied for comparison and correlation between an endemic fluorotic village Rukh Mudke (RM), n = 74, and a non-fluorotic village Ottawa (OTW), n = 60. The children were aged between 7-18 years and selected for the estimation of fluoride in their household water, body fluids (urine-serum), dental fluorosis and thyroid hormones (Free tri-iodothyronine (FT3) free tetra iodothyronine (FT4) and thyroid stimulating hormone (TSH) respectively. Mean concentration of water fluoride in subjects of RM was 4.6 ×106 ng/L, urine fluoride 2.59 ×106 ng/L, serum fluoride 6.0 ×104 and dental fluorosis 90.5% respectively. Significant elevation (P = 0.000) in the concentration of three out of these four variables (P < 0.01) was observed (except in serum fluoride) in subjects of RM compared to those in the control group (OTW). Mean FT4, FT3 and TSH concentrations in RM subjects was 18.3 pmol/L, 5.06 pmol/L and 3.2 mlU/L respectively. No marked difference in FT4 and FT3 (P = 0.17 and P = 0.7) was found compared to the control (OTW) group, while significant elevation in TSH (P < 0.05) was found in. 22% of the children in the RM group, portrayed well defined thyroid hormonal aberrations. A negative correlation between water fluoride - FT4 (r = - 0.24); a strong positive between water, urine, serum, dental fluorosis and TSH (r = 0.94, 0.87, 0.88, 0.74 and 0.8) and moderate correlation between water fluoride - FT3 (r = 0.52) was observed. Results of this study indicate that the fluoride intoxication through drinking water is not only increasing fluoride level in body fluids and deteriorating teeth but also destroying thyroid function in a large number of children.

Is there any association between fluoride exposure and thyroid function modulation? A systematic review

“…Clinically, elevated TSH levels often correlate with reduced T3 and T4 production, indicating a response to hormone deficiency and a need for increased production and release. This pattern was observed in studies by Khandare, Validandi [ 23 ] and [ 24 , 25 ], although [ 22 ] reported no such correlation. Moreover, while an increase in PTH is relevant, it does not directly influence thyroid functions.…”

“…The studies did not categorize participants according to life stages, such as childhood, adolescence, adulthood, middle age, or senior years. Wang, Wang [ 22 ], Kutlucan, Koroglu [ 15 ], Khandare, Validandi [ 23 ], Zulfiqar, Rehman [ 24 ] and Zulfiqar, Ajaz [ 25 ] evaluated participants ranging in age from 7 to 18 years. Conversely, Leone, Leatherwood [ 20 ] focused on adult and older individuals, with ages ranging from 18 to 60 years.…”

“…Two studies were considered high risk in the bias due to confounding domain and due to some concerns regarding potential risk of bias arising from measurement of the outcome [20,21]. Four included studies were considered low risk [15,[22][23][24]. However, one study was PLOS ONE considered some concerns in the bias due to potential risk of bias from measurement of the exposure [25].…”

Iodine Status in Pregnant Women Having Urinary Fluoride in Contaminated Areas: A Case Study of Phayao Province

“…In addition, T3 incorporation may be diminished, resulting in the production of prolactin TSH, which limits thyroid iodine absorption by fuorine. As a result, both the secretion of T4 and the stimulating impact of exogenous THS are diminished [23][24][25]. Studies in this area have revealed that enhanced consumption of fuoride in drinking water causes changes in hormones related to thyroid function (TSH, T3, FT3, T4, FT4, and rT3) and adjustments in the actions of deiodinase enzymes [5,[26][27][28].…”

Dental Fluorosis in Children from Aguascalientes, Mexico: A Persistent Public Health Problem

“…Dental fluorosis and skeletal fluorosis are major public health concerns around the world. Regions with a high prevalence of such illnesses have been recently documented in Asia, particularly in China [1][2][3][4], India [5][6][7][8], Pakistan [9][10][11], and Sri Lanka [12][13][14]. In Africa, dental fluorosis is prevalent mainly in Sub-Saharan countries, including Kenya, Tanzania, Uganda, Ethiopia, Eritrea, Sudan, Ghana, Malawi, Niger, Nigeria, Mozambique, and South Africa [15][16][17].…”