Lung damage after long-term exposure of adult rats to sodium fluoride.
BACKGROUND
Fluorides, when taken in amounts exceeding the standard therapeutic dosage, are regarded as toxic substances. Chronic fluorosis causes marked destruction of lung tissues. The study aimed to determine whether the effect of a chronic toxic dose of sodium fluoride on the lung of an adult male albino rat is reversible or irreversible. This was done through light and electron microscopic studies. Morphometric study was also done.


METHODS
Forty adult male rats were used. The animals were divided into 3 groups: control group; group I (chronic fluorosis group) in which sodium fluoride was given daily for 3 months; and group II (recovery group) in which sodium fluoride was given daily for 3 months and after that the rats survived for another month.


RESULTS
The lung of group I was characterized by presence of blood and lymph congestion. Thickening of alveolar septa was also observed with rupture of septa and widening of the air spaces. The area % of collagen (1.13 ±0.5), septal wall thickness (13.47 ±6.1), and number of macrophages (5 ±2.5) increased in comparison to the control group (p ≤ 0.05). With discontinuation of sodium fluoride (group II), no much improvement was observed.


CONCLUSIONS
Chronic fluorosis has many pathological effects on the lung which are irreversible.
Department of Anatomy, Faculty of Medicine, Cairo University, Cairo, Egypt.
Fayza Abdel-Raouf
FA
Abdel-Gawad
Department of Anatomy, Faculty of Medicine, Cairo University, Cairo, Egypt.
Maha Hussein
MH
Ashmawy
Department of Anatomy, Faculty of Medicine, Cairo University, Cairo, Egypt.
Sherif Mohamed
SM
Zaki
Department of Anatomy, Faculty of Medicine, Cairo University, Cairo, Egypt.
Gaber Hassan
GH
Abdel-Fatah
chronic fluorosis; lung damage