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PubMedDate not supplied

[Environmental pollution studies of fluorine coming from industry].

Fluorine in optimal concentration prevents dental caries, while an excess or deficiency in it may lead to pathologic alterations which make fluorine be one of the environmental pollutants the concentration of which is limited by health standards. This investigation, carried out in the area of an aluminium plant, showed the presence in excess of fluorine and fluorine-containing dusts in the atmospheric air, determining an increased fluorine content in the ground and vegetal cultures of the respective area. Negative effects of these noxae upon vegetation and animals were noticed.

Air Pollutants↗
PubMed2004

[Study on the calcium-based sorbent for removal fluorine during coal combustion].

In the paper, the reaction of CaO-HF and fluorine removal mechanics at high temperature by blending calcium-based sorbents with coal during coal combustion were discussed, and test results about fluorine retention during coal combustion in fluidized bed and chain-grate furnace were reported. The results identified that lime and calcium-based sorbets developed can restratin the emission of fluorine during coal combustion. The efficiency of fluorine removal can reach 66.7%-70.0% at Ca/F 60-70 by blending lime with coal in fluidized bed combustion, and the efficiency of fluorine removal are between 57.32% and 75.19% by blending calcium-based sorbets with coal in chain-grate furnace combustion. Blending CaO or lime with coal during coal combustion can remove SO2 and HF simultaneously.

Absorption↗
PubMed2005

[Pilot experiment of fluorine fixing ratio of coated lump stone coal fuel].

The pilot experiment on coated lump stone coal fuel selected from 16 families in Haoping Shanxi were studied. 8 families burned coating high fluorine lump stone coal with lime, clay and low fluorine anthracite, 8 families burned untreated lump stone coal. The results show that the fluorine-fixing ratio at treated group was 75.0% when coal fluorine compared with coal cinder fluorine. In comparison with untreated group, the concentration of door air fluoride lowered 85.7%, SO2 lowered 75.0%, dust lowered 55.3%.

Air Pollution, Indoor↗
PubMed2006

[Quality evaluation of soil fluorine on Hangjiahu Plain based on GIS].

Contents of fluorine in the plough layer (0-20 cm) of paddy soils from Hangjiahu Plain were investigated to evaluate quality of fluorine using total fluorine index method. Kriging method was applied to study the spatial variability of soil total fluorine in relation to their influential factors and their distribution maps were obtained based on GIS. The results showed that the range of total fluorine (TF) contents in the soils from central and eastern parts of Hangjiahu Plain was higher than that from the western part. The concentrations of TF in soil had a close relationship with parent material, pH value, organic matter, cation exchange capacity content and soil texture. The main range of TF was 200-300 mg/kg, while TF contents accounting for 23.7% of the area were less than 200 mg/kg in the studied area. In which TF contents in soil in Yuhang County were the lowest, less than 100 mg/kg.

China↗
PubMed1991

[Aluminum and fluorine absorption in a perfusion system of rat small intestine in vivo].

Mixtures of aluminum an fluorine in two different ratios in tris-hydroxy-methyl-aminomethane buffered media of pH 7.0 were perfused respectively through the small intestine of the in vivo rat over a period of 40 min. The contents of aluminum and fluorine in the portal vein blood obtained from different perfusion periods were detected and determined simultaneously. The results showed that fluorine absorption was not significant in the mixtures. An obviously large amount of aluminum was absorbed in the mixture with a higher proportion of aluminum (4660 micrograms/ml Al + 200 micrograms/ml F/L), while in the mixture with a lower dose of aluminum (860 micrograms/ml Al + 200 micrograms F/L), a small quantity of aluminum was absorbed. It is evident that the mechanism by which aluminum inhibits fluorine toxicity is that aluminum decreases the intestinal fluorine absorption by the formation of aluminum fluoride complex.

Aluminum↗
PubMed1991

[Effect of emissions from the Household Glassware Factory (HGF) "Irena" in Inowrocław on the levels of fluorine and lead in selected vegetables and fruit harvested in 1988].

Fluorine and lead were determined by spectroscopic methods in some vegetables harvested in 1988 in two groups of Employees' Gardens in Inowrocław ("Transportowiec" and "Irena", distant from the Household Glassworks "Irena" by ca. 500 and 2600 m, respectively). Employees' Gardens "Irena" were divided into 2 belts, in consideration of a vicinal traffic artery. It was found that 42% of the plants harvested in Employees' Gardens "Transportowiec" exhibited excessive contents of fluorine, and 91%--of lead; fluorine contamination of vegetables was, however, slight, except for parsley leaves containing 56.0 mg F per 1 kg dry weight. In the case of Employees' Gardens "Irena", in the I belt (30-40 m from the traffic artery) the level of fluorine was excessive in 8.3% of plants, and that of lead--in 63.6% of plants; in the II belt (80-100 m from the traffic artery) the respective values were 17% for fluorine and 66.6% for lead.

Air Pollutants↗
PubMedDate not supplied

[Fluorine content in natural cow milk from the region of Plovdiv].

Fluorine content in natural cow milk has been determined with a view to the fluoration of the milk and its use for dental caries prophylaxis. Fluorine has been determined by the method of standard calibration, making use of fluorine selective electrode and "Orion SA 720 pH/ISE Meter" with LCD display. The mean fluorine quantity in milk is mean = 0.046 ppm, being far lower than the optimal fluorine concentration.

Animals↗
PubMed1988

Biotransformation of isoflurane: urinary and serum fluoride ion and organic fluorine.

The serum and urinary concentrations of fluorinated metabolites of isoflurane after inhalation of three different concentrations of isoflurane were studied in 18 ASA physical status 1 or 2 patients, scheduled for orthopedic or otolaryngeal surgery. Isoflurane was administered for 60 min during fentanyl-nitrous oxide-oxygen, and its end-tidal concentration was maintained at 0.3, 0.6, or 1.15% (groups I, II, and III). The organic fluorine was determined by combustion and fluoride ions were analyzed by ion chromatography. The amounts were expressed in terms of fluoride ion. The concentrations of serum fluoride ion and organic fluorine increased significantly 15 min after the onset of inhalation of isoflurane. The mean peak values of fluoride ions were 3.8 +/- 1.1, 3.9 +/- 1.4, and 4.2 +/- 0.9 mumole/1 (M +/- SD) in patients in groups I, II, and III, respectively. The half-lives of fluoride ion and of organic fluorine as metabolites of isoflurane, calculated from the amounts excreted in urine, were 36 h and 41 h, respectively. The cumulative amounts of fluoride ion and organic fluorine excreted up to the 6th postoperative day were 548 +/- 230 and 785 +/- 452 mumoles in group I, 594 +/- 138 and 1,378 +/- 807 mumoles in group II, and 1,032 +/- 496 and 728 +/- 265 mumoles (M +/- SD) in group III, respectively. The urinary excreted fluoride ion increased in proportion to the dose of isoflurane and approximately 1.3 mmol was excreted per 1 MAC X hour inhalation of isoflurane. The authors concluded that isoflurane might be biotransformed to a greater extent than reported previously, although the serum fluoride ion level was found to be low.

Adult↗
PubMed1979

[Ionized fluorine in the plasma and urine of subjects treated with organofluorine drugs prescribed in rheumatology].

The elimination of ionized urinary fluorine was studied in groups of eight subjects treated during several days with niflumic acid, flufenamic acid, sulindac, antrafenine and floctafenine. Sulindac and floctafenine do not changes this elimination. After administration of niflumic acid, flufenamic and antrafenine, the urinary elimination of ionized fluorine increase in all the subjects. This increase is manifested from the start of treatment and persists for several days after it has been stopped. The administration of three drugs also results in an elevated level of ionized plasmic fluorine the duration of treatment. The results prove the existence in the human organism of a metabolic process capable of effecting the ionization of the organic fluor contained in the drugs studied. This biotransformation causes a fluorine impregnation of endogenous origin that is permanent and relatively stable, and whose consequences are examined (risk of fluorine osteosis and possibility of therapeutic application).

Anti-Inflammatory Agents↗
PubMedDate not supplied

[Action of the body fluorine of healthy persons and thyroidopathy patients on the function of hypophyseal-thyroid the system].

Altogether 123 persons were examined: 47 healthy persons, 43 patients with thyroid hyperfunction and 33 with thyroid hypofunction. It was established that prolonged consumption of drinking water with a raised fluorine content (122 +/- 5 mumol/l with the normal value of 52 +/- 5 mumol/l) by healthy persons caused tension of function of the pituitary-thyroid system that was expressed in TSH elevated production, a decrease in the T3 concentration and more intense absorption of radioactive iodine by the thyroid as compared to healthy persons who consumed drinking water with the normal fluorine concentration. The results led to a conclusion that excess of fluorine in drinking water was a risk factor of more rapid development of thyroid pathology. Indicators of the fluorine content in daily urine provide most of the information on changes of the fluorine amount in the body.

Adolescent↗
PubMed1984

[Kinetics of fluorine elimination in exposed workers].

The fourteen-day kinetics of fluorine (F) elimination in urine was followed up in 24 operators from three main workshops of the plant for phosphorous fertilizers. The concentration of F in urine was determined at the beginning, by 6th h and during the last two hours of a working shift in four successive days and at the beginning of the following production cycle after the discontinuation of the exposure. In parallel, the gas-like fluorine compounds in the air of working environment was also determined. Analogous investigations were performed with a control group--30 non-exposed workers. A potentio-metric method with fluorine-selective electrode was used for the determination of F content in urine and the concentration of the gas-like fluorides in the air. A well manifested tendency to increased excretion was established by the end of the working shift and in the course of the working cycle. The data on the rate of fluorine elimination show that it is the highest during the last two exposure hours, most manifested in the workers from the workshop TSP, less-in the workshop PhA and least--in the workshop NTPP. The concentration of fluorine ions in urine for the three groups of workers investigated, was increased as compared with control values, both by 6th h and during the last two hours.

Bulgaria↗
PubMed1982

Mouse skin tumor-initiating activity of 5-, 7-, and 12-methyl- and fluorine-substituted benz[a]anthracenes.

As an approach for elucidation of structure activity relationships that underlie the exceptionally large difference in carcinogenic activity between benz[a]anthracene and 7,12-dimethylbenz[a]anthracene (7,12-DMBA), 11 methyl- and/or fluorine-substituted benz[a]anthracenes were evaluated for tumor-initiating activity on mouse skin. Outbred CD-1 and outbred Sencar mice received a single topical application of the hydrocarbons followed by twice weekly applications of the tumor promoter 12-O-tetradecanoylphorbol 13-acetate for 16-26 weeks. 7,12-DMBA was almost two orders of magnitude more active as a tumor-initiator than 7- and 12-methylbenz[a]anthracene. Methyl substitution at the 7- and 7,12-positions of benz[a]anthracene was significantly more effective in the enhancement of tumorigenic activity than fluorine substitution at these positions. Although 7-fluorobenz[a]anthracene, 12-fluorobenz[a]anthracene, and 7,12-difluorobenz[a]anthracene had only 0.15, 0.26, and less than 0.005 times the tumor-initiating activity of their respective methyl-substituted derivatives, they were severalfold more active than benz[a]anthracene. 7-Fluorobenz[a]anthracene was slightly less active than 12-fluorobenz[a]anthracene, whereas 7-methylbenz[a]anthracene was about twofold more than 12-methylbenz[a]anthracene. For 7,12-di-substituted benz[a]anthracenes, 7-methyl-12-fluorobenz[a]anthracene was more than twice as tumorigenic as 7-fluoro-12-methylbenz[a]anthracene, but each was individually more active than 7-methylbenz[a]anthracene and 12-methylbenz[a]anthracene, respectively. Both fluorinated compounds were much less active than 7,12-DMBA. Substitution of fluorine or methyl at the 5-position of 7-methylbenz[a]anthracene and substitution of fluorine at the 5-position of 12-methylbenz[a]anthracene dramatically reduced their tumorigenic activity.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1982

[Effect of fluorine on development of experimental atherosclerosis].

A four-month experiment with rabbits was carried out, aiming at the elucidation of fluorine effect in the development of experimental hypercholesterolemia. The experimental animals were grouped into five groups: group I--control; group II--treated with 0,5 mg/kg cholesterol; group III--administered 10 MAC fluorine; group IV and V--treated with combination fluorine and cholesterol. The animals were monthly examined and the dynamics of body weight, total blood count were followed up as well as the biochemical indices/ total lipids, cholesterol, beta-lipoproteins, blood sugar, urea, uric acid and some electrolytes/. Femurs and teeth of the experimental animals were tested for fluorine content and dry substance in them. Pathoanatomical and histochemical investigations were also performed. The results obtained allow to admit that fluorine, as a mictoelement, plays a certain role in the inhibition of the development of the experimental hypercholesterolemia and atherosclerosis.

Animals↗
PubMed1994

Ultrastructural localization of a fluorinated bile salt in hepatocytes.

BACKGROUND: Interactions of bile salts with hepatocellular organelles are critical for the formation of bile, yet these interactions remain poorly characterized. We present a novel approach for visualizing bile salts at the ultrastructural level within hepatocytes, using a unique fluorinated bile salt conjugate and electron energy loss spectroscopy. EXPERIMENTAL DESIGN: Isolated rat hepatocytes were incubated for 5 and 20 minutes with the 2-fluoro-beta-alanine (FBAL) N-acyl amidate conjugate of cholic acid (C-FBAL, 50 microM). FBAL is a byproduct of hepatic 5-fluorouracil catabolism, and when conjugated to cholic acid is excreted into bile in a manner similar to the naturally occurring N-acyl amidates of bile salts. Cells were subjected to rapid cryofixation and automated freeze-drying followed by vapor-phase fixation using the LifeCell system, thus avoiding exposure to the leaching action of liquid fixatives. After resin infiltration, the cellular distribution of fluorine was determined in ultrathin sections with a Zeiss CEM902 electron microscope equipped for electron energy loss spectroscopy. RESULTS: Fluorine was detected primarily in association with intracellular membranes, particularly membranes of the endoplasmic reticulum (p < 0.05 at 20 minutes by morphometric analysis). Fluorine also was detected in association with membranes of the Golgi apparatus. The fluorine signal was confirmed by serial spectra of cell regions containing these organelles (p < 0.01), but was not detectable in the free cytosol, mitochondria or extracellular medium, nor in hepatocytes not exposed to C-FBAL. CONCLUSIONS: We conclude that cryofixation and freeze-dry processing followed by electron microscopy with electron energy loss spectroscopy is a valuable technique for examining intracellular processing of bile salts. Our results suggest that bile salts localize to the membranes, but not lumena, of organelles during hepatocyte exposure to bile salts, calling into question the proposed role for vesicular transport of bile salts within hepatocytes.

Animals↗
PubMedDate not supplied

High fluorine water to wether sheep maintained in pens. Aluminum chloride as a possible alleviator of fluorosis.

The experiment reported here, gave the following answers to the questions asked (see introduction): a. Water with 30 ppm F gave deleterious effects on wethers. A considerable difference was observed as compared to animals given about 1 ppm F in their water, see Table IV. b. The toxicity was slightly less from bore hole water containing 30 ppm F, as compared to Nairobi tap water with added fluorine to 30 ppm F. The difference in toxicity may be due to the very high content of minerals in the bore hole water, see Table I. c. More fluorine was excreted in faeces when aluminum chloride was added to the diet, as compared to animals which did not receive aluminum chloride. Aluminum chloride had no alleviating effect on fluorosis, but apparently decreased gut absorption of fluorine and also reduced fluorine retention in the bones, se Table VII. Under the conditions of this experiment, toxic levels of fluorine were considerable lower than the quoted safe levels in the literature.

Aluminum↗
PubMed2006

Fluorinated molecules as drugs and imaging agents in the CNS.

The strategic use of fluorine substitution in drug discovery and drug development is well documented. The small size and high electronegativity of fluorine are among properties of this element that lend special advantages. Applications in drugs targeted to the central nervous system (CNS) have been particularly fruitful in addition to favorable properties seen in many peripherally acting drugs. Fluorine substitution can be used to solve problems unique to the CNS, such as blood brain barrier (BBB) penetration. Likewise, use of the positron emitting isotope, (18)F, provides a unique tool for non-invasive imaging and diagnoses in the CNS. In this review, fluorine in CNS drugs and drug discovery are discussed.

Animals↗
PubMed2001

Reactions of BBr(n)(+) (n = 0--2) at fluorinated and hydrocarbon self-assembled monolayer surfaces: observations of chemical selectivity in ion--surface scattering.

Ion-surface reactions involving BBr(n)(+) (n = 0--2) with a fluorinated self-assembled monolayer (F-SAM) surface were investigated using a multi-sector scattering mass spectrometer. Collisions of the B(+) ion yield BF(2)(+) at threshold energy with the simpler product ion BF(+)* appearing at higher collision energies and remaining of lower abundance than BF(2)(+) at all energies examined. In addition, the reactively sputtered ion CF(+) accompanies the formation of BF(2)(+) at low collision energies. These results stand in contrast with previous data on the ion-surface reactions of atomic ions with the F-SAM surface in that the threshold and most abundant reaction products in those cases involved the abstraction of a single fluorine atom. Gas-phase enthalpy data are consistent with BF(2)(+) being the thermodynamically favored product. The fact that the abundance of BF(2)(+) is relatively low and relatively insensitive to changes in collision energy suggests that this reaction proceeds through an entropically demanding intermediate at the vacuum--surface interface, one which involves interaction of the B(+) ion simultaneously with two fluorine atoms. By contrast with the reaction of B(+), the odd-electron species BBr(+)* reacts with the F-SAM surface to yield an abundant single-fluorine abstraction product, BBrF(+). Corresponding gas-phase ion--molecule experiments involving B(+) and BBr(+)* with C(6)F(14) also yield the products BF(+)* and BF(2)(+), but only in extremely low abundances and with no preference for double fluorine abstraction. Ion--surface reactions were also investigated for BBr(n)(+) (n = 0-2) with a hydrocarbon self-assembled monolayer (H-SAM) surface. Reaction of the B(+) ion and dissociative reactions of BBr(+)* result in the formation of BH(2)(+), while the thermodynamically less favorable product BH(+)* is not observed. Collisions of BBr(2)(+) with the H-SAM surface yield the dissociative ion-surface reaction products, BBrH(+) and BBrCH(3)(+). Substitution of bromine atoms on the projectile by hydrogen or alkyl radicals suggests that Br atoms may be transferred to the surface in a Br-for-H or Br-for-CH(3) transfer reaction in an analogous fashion to known transhalogenation reactions at the F-SAM surface. The results for the H-SAM surface stand in contrast to those for the F-SAM surface in that enhanced neutralization of the primary ions gives secondary ion signals one to two orders of magnitude smaller than those obtained when using the F-SAM surface, consistent with the relative ionization energies of the two materials.

Journal Article↗
PubMed2002

Langmuir monolayers and the transferred films of fluorinated amphiphiles containing vinyl groups.

The monolayer behavior of long-chain esters of acrylic and methacrylic acids containing perfluoro or partially fluorinated carbon chains at the air/water interface was studied by surface pressure-area isotherm measurements and Brewster angle microscopy. It has been found that a minor change in the chemical structures of these fluorinated amphiphiles, such as a hydrogen substituted at the omega-position of the hydrophobic fluorocarbon tails instead of a fluorine as well as hydrophilic vinyl ester groups inserted between acrylates and methacrylates, induces a drastic change in the isotherms for the monolayers, suggesting different molecular orientation and packing in the films. The monolayers were transferred by horizontal lifting, Langmuir-Blodgett, and surface-lowering methods to give the X-, Y-, and Z-type films, respectively. These films were characterized by scanning probe microscopy, to clarify the mesoscopic surface structures of the molecular films exposed with the hydrophilic or hydrophobic moieties in air, depending upon the dipping methods. The Z-type films with the outermost surface of the fluorinated substituents were examined in relation to the frictional properties that strongly depend upon the fluorine and the hydrogen atoms at the end of the hydrophobic fluorocarbon chains, which is controllable at the atomic level.

Journal Article↗