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1996 Fluoride Abstracts. Part 2.

Abstracts for the following years:
Part 1 - mainly biochemistry and physiology (brain, hormonal, G-proteins, etc.)
Part 2 ("b") - all other

2007

2007-b

2004

2004-b

2001

2001-b

1998

1998-b

1995

1995-b

1992

1992-b

1989

1989-b

1986

1986-b

1983

1982

1976 -
1977
1970 -
1971

2006

2006-b

2003

2003-b

2000

2000-b

1997

1997-b

1994

1994-b

1991

1991-b

1988

1988-b

1985

1985-b

1981

1980

1974 -
1975
1968 -
1969

2005

2005-b

2005-b continued

2002

2002-b

1999

1999-b

1996

1996-b

1993

1993-b

1990

1990 -b

1987

1987-b

1984

1984-b

1979

1978

1972 -
1973
Up to
1967


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8908873&dopt=Abstract

J Can Dent Assoc 1996 Sep;62(9):708-9, 712-5

Comparison of recommended and actual mean intakes of fluoride by Canadians.

Lewis DW, Limeback H.

Faculty of Dentistry, University of Toronto, Ont.

The findings of two separate 1993 reports, one of the actual intake of fluoride by Canadians and the other on their recommended fluoride intake, are summarized and compared. Recent increases in very mild and mild dental fluorosis suggest that the gap between current fluoride intake and recommended intake is narrowing. The daily swallowing of fluoride dentifrice makes a large contribution to the actual total daily fluoride intake, especially in children seven months to four years of age, the age group most susceptible to fluorosis in the anterior permanent teeth. Because of the available data and methods used in each study, the reported actual and recommended fluoride intakes vary greatly both within and between age groups. It is likely that individual variation in fluoride intake also varies greatly. Comparison of the data in the two reports revealed that, for breast-fed infants and nearly all other age groups without fluoridated water, the ranges of the estimates of actual intake are lower than the recommended ranges. However, for formula-fed infants and all other age groups using fluoridated water, the estimates of actual intake greatly exceed the recommended intake, especially for the seven months to four years age group. Ingestion of fluoride at these levels during tooth development will contribute to dental fluorosis. All of the age groups have fluoride intake estimates below levels at which skeletal signs of fluoride exposure are noticed. Nevertheless, exposure to fluoride should be closely monitored and inappropriate use of discretionary fluorides curtailed.

PMID: 8908873 [PubMed - indexed for MEDLINE]


Journal of the American Dental Association 1996; 127(7):895-902

Assessing fluoride concentrations of juices and juice-flavored drinks

Kiritsy MC, Levy SM, Warren JJ, Guha-Chowdhury N, Heilman JR, Marshall T

Reprints: Dental Research Unit, Health Research Council, Wellington School of Medicine, PO Box 27007, Wellington, New Zealand

Few studies have investigated fluoride exposures from juices and juice-flavored drinks manufacured with water. In this study, the authros analyzed 532 juices and juice drinks for fluoride. Fluoride ion concentrations ranged from 0.02 to 2.80 parts per million, in part because of variations in fluoride concentrations of water used in production. Children's ingestion of fluoride from juices and juice-flavored drinks can be substantial and a factor in the development of fluorosis.


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=8677830

Am Fam Physician 1996 Jul;54(1):138-44

Comment in:

Practical nutrition for the healthy term infant.

Spencer JP.

Conemaugh Valley Memorial Hospital, Johnstown, Pennsylvania, USA.

Breast milk is universally recommended as the preferred source of infant nutrition, in part because of its superior nutrient and immunologic properties. Successful breast feeding requires nursing on demand, prevention of sore nipples and convenient access to medical advice. For mothers relying on bottle feeding, cow's-milk-based formula is the preferred choice. Because soy-based formulas are lactose-free, they may be tolerated by infants who are allergic to cow's-milk protein. Protein hydrolysate formulas should be used only in infants who cannot tolerate cow's-milk-based or soy-based formulas. Low-Iron formulas and whole cow's milk should not be used during the first year. Breast-fed infants rarely require vitamin supplementation. Fluoride supplementation is no longer recommended for infants less than six months of age.

Publication Types:

PMID: 8677830 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8639113&dopt=Abstract

Aust Dent J 1996 Feb;41(1):37-42

Fluoride content of infant formulae in Australia.

Silva M, Reynolds EC.

School of Dental Science, University of Melbourne.

The prevalence of dental fluorosis in Australia and the United States of America has increased in both optimally fluoridated and non-fluoridated areas. This has been attributed to an increase in the fluoride level of food and beverages through processing with fluoridated water, inadvertent ingestion of fluoride toothpaste, and the inappropriate use of dietary supplements. A major source of fluoride in infancy is considered to be infant formula which has been implicated as a risk factor for fluorosis in a number of studies. In this study the fluoride content of the infant formulae commonly used in Australia was determined. The acid diffusible fluoride of each powdered formula was isolated by microdiffusion and measured using a fluoride ion-specific electrode. The fluoride content of milk-based formulae ranged from 0.23 to 3.71 micrograms F/g and for soy-based formulae from 1.08 to 2.86 micrograms F/g. When reconstituted, according to the manufacturer's directions, with water not containing fluoride, the formulae ranged in fluoride content from 0.031 to 0.532 ppm, with the average fluoride content 0.240 ppm. Using average infant body masses and suggested volumes of formula consumption for infants 1-12 months of age, possible fluoride ingestion per kg body mass was estimated. None of the formulae, if reconstituted using water containing up to 0.1 ppm F, should provide a daily fluoride intake above the suggested threshold for fluorosis of 0.1 mg F/kg body mass. However, if reconstituted with water containing 1.0 ppm F they should all provide a daily fluoride intake of above the suggested threshold for fluorosis with intakes up to 2-3 times the recommended upper 'optimal' limit of 0.07 mg/kg body mass. Under these conditions the water used to reconstitute the formulae would provide 65-97 percent of the fluoride ingested. These figures are likely to be overestimates due to the intake of nutrients from other sources reducing formulae consumption and also due to the lower bioavailability of fluoride from milk-based formulae. Further, it is generally believed that the maturation stage of enamel formation is the critical period for fluorosis development by chronic, above-threshold fluoride exposure. The maturation stage for the anterior permanent teeth, however, is after the first twelve months of life where fluoride intake from infant formula consumption per kg body mass is highest. The level of fluoride in the commonly used Australian formulae would suggest that infant formula consumption alone is unlikely to be a risk factor for dental fluorosis in a non-fluoridated community, but could make a major contribution to an infant's daily fluoride intake. However, prolonged consumption (beyond 12 months of age) of infant formula reconstituted with optimally-fluoridated water could result in excessive amounts of fluoride being ingested during enamel development of the anterior permanent teeth and therefore may be a risk factor for fluorosis of these teeth.

PMID: 8639113 [PubMed - indexed for MEDLINE]


From TOXNET

Teratology 1996 Apr;53(4):276
also published in
Am J Epidemiol 1996;143(11 Suppl):S1

Maternal occupational exposures as risk factors for neural tube defects.

Shaw GM, Velie EM, Katz EA, Morland KB, Harris JA

California Birth Defects Monitoring Program, Emeryville, CA.

Abstract: Numerous studies have investigated whether a woman's occupational exposures during early pregnancy increases her risk for offspring with neural tube defects (NTDs). Most studies have relied on industry/job titles as surrogates for maternal exposures. To avoid errors associated with such proxy exposure measures, we designed a process whereby an industrial hygienist imputes specific exposures from maternal histories. Women were asked in a structured interview about their occupational and nonoccupational (hobbies) tasks performed during 3 months before through 3 months after conception. An industrial hygienist used several a priori defined exposure categories to assign to each woman. The primary category consisted of 74 chemical families, e.g., alcohols, lead compounds. Another defined exposure category included "end-use" products, e.g., solvents, insecticides, propellants, plastics, dyes. Face-to-face interviews were conducted with mothers of 538 (87.8% of eligible) NTD-affected infants/fetuses (including those prenatally diagnosed and electively aborted), and mothers of 539 (88.1%) randomly selected, non-malformed, liveborn infants, from a population-based 1989-91 cohort of births (N = 703,518). The majority of case (66%) and control mothers (74%) had employment between 3 months before and 3 months after conception. Odds ratios of 1.5 or greater were observed for maternal exposures to 14 of the 74 chemical families. The 14 included antibiotics, antineoplastic drugs, aromatic amines, chromium, cyanide, fluoride, halogenated organics, isocyanates, methacrylates, organophosphates, organic-acids, peroxides, other pesticides, and steroids. The 95% confidence intervals for the 14 risk estimates, however, all included 1.0. For occupational exposures involving the 10 "end-use" products, an elevated odds ratio was observed for insecticides, 1.6 (0.81-3.1), but not for other products including solvents. Considering nonoccupational exposures did not substantially change results. Single variable adjustment for multivitamin use, race/ethnicity, and education level also did not substantially alter observed relations.


See full article

British Occupational Hygiene Society Vol. 40, No. 6 pp. 705-710, 1996

FATALITY DUE TO ACUTE FLUORIDE POISONING FOLLOWING DERMAL CONTACT WITH HYDROFLUORIC ACID IN A PALYNOLOGY LABORATORY

Luciano Muriale, * Evelyn Lee,* John Genovese+ and Steven Trend*

*WorkSafe Western Australia, P.O. Box 294, West Perth, WA 6872, Australia;and Chemistry Centre of Western Australia, 1250 Hay Street, East Perth, WA 6004, Australia

Abstract-A fatal accident involving concentrated hydrofluoric acid in a palynological laboratory is described. Similar deaths due to dermal exposure to concentrated hydrofluoric acid have been reported in the literature. It is evident that rigorous control measures including proper personal protective equipment and first aid are of utmost importance in the prevention of death and injury when handling hydrofluoric acid. Possible factors that may have contributed to the accident are reviewed. Copyright © 1996 British Occupational Hygiene Society.


Fluoride 1996; 29(1):3-6

Effects of fluoride on growth and soluble sugars in germinating mung bean (Vigna radiata) seeds

Ming-Ho Yu

Center for Environmental Sciences, Western Washington University, Bellingham, Washington

Summary: The influence of NaF on the growth and soluble sugar contents of mung bean (Vigna radiata) seedlings was studied. One-day-old seedlings were treated with 0, 0.1, 1.0, or 5.0 mM NaF at 25¼C for 72 h, and the wet weight, root elongation, and soluble sugar levels of the seedlings were determined. Wet weight of the cotyledons was increased while the weight and length of radicles were significantly depressed in seedlings exposed to NaF at and above 1.0 mM. Total soluble sugars and, particularly, reducing sugars, decreased with increase in F concentration. The results suggest that an impaired sugar metabolism may be an important factor contributing to the observed inhibition of germination in mung bean seedlings exposed to NaF.


Fluoride 1996; 29(1):7-12

Relationship between total fluoride intake and dental fluorosis in areas polluted by airborne fluoride

Chen YX (a), Lin MQ (a), He ZL (a), Xiao (a), Chen C (a), Min D (a), Liu YQ (a), Yu MH (b)

(a) Jiangxi Institute of Labor Hygiene and Occupational Medicine, Nanchang, Jiangxi, China
(b) Center for Environmental Sciences, Huxley College of Environmental Studies, Western Washington University, Bellingham, Washington

Summary: The relationship between fluoride (F) exposure and dental fluorosis in three (two experimental and one reference) villages in Jiangxi Province, China, has been studied. Total daily F-intakes by adults in the two F-exposed areas, Changping Village and Wenpan Village, were 3.16 and 3.01 mg, whereas the incidence of dental fluorosis was 51.8% and 57.4%, respectively. Airborne F levels of the two experimental villages were similar to each other, but the SO2 level in the air was higher in Wenpan Village than in Changping Village. On the other hand, food borne F levels in Changping Village was higher than those in Wenpan Village. The levels of kitchen airborne F and SO 2 in the experimental areas were much higher than those in the reference area. Results from animal experiments showed that more dental lesions occurred in rats expoed to both F and SO2 than in those exposed to F along. These results suggest that SO2 may be important in enhancing F-induced dental fluorosis.


Fluoride 1996; 29(1):13-19

Effect of sodium fluoride on the transmural potential difference of the rat stomach

Gharzouli K, Gharzouli A, Aiouaz L, Berais A

Institut de Biologie, Universite Ferhat Abbas, 1900 Setif, Algeria

Summary: Transmural potential difference (PD) was measured in vivo under continuous perfusion of the rat stomach. Luminal NaF (5mM) perfusion elicited a net temporal decrease of PD, whereas lower NaF concentrations (1 and 2 mM) had no effect. The fall of PD induced by 5 mM was abolished at pH 8.4 and was enhanced (161%) at pH 3.2. Compared to NaF alone, the decrease of PD induced by the simultaneous perfusion of NaF and salicylic acid (5 mM each) was more pronounced (209%) with a previous perfusin of salicylllic acid alone than the direct pefusion of NaF and salicylic acid (136%). These results suggest that the observed variations of PD reflect the early functional alterations of the mucosa preceding the structural damaging effects of hydrofluoric and salicylic acids.


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8958774&dopt=Abstract

Ann Occup Hyg 1996 Dec;40(6):705-10

Fatality due to acute fluoride poisoning following dermal contact with hydrofluoric acid in a palynology laboratory.

Muriale L, Lee E, Genovese J, Trend S.


WorkSafe Western Australia, West Perth, Australia.

A fatal accident involving concentrated hydrofluoric acid in a palynological laboratory is described. Similar deaths due to dermal exposure to concentrated hydrofluoric acid have been reported in the literature. It is evident that rigorous control measures including proper personal protective equipment and first aid are of utmost importance in the prevention of death and injury when handling hydrofluoric acid. Possible factors that may have contributed to the accident are reviewed.

PMID: 8958774 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8953969&dopt=Abstract

Ann Emerg Med 1996 Dec;28(6):713-8

Comment in:


Marked hypocalcemia and ventricular fibrillation in two pediatric patients exposed to a fluoride-containing wheel cleaner.

Klasaer AE, Scalzo AJ, Blume C, Johnson P, Thompson MW.

Cardinal Glennon Regional Poison Center, St Louis, Missouri, USA.

In two separate cases, pediatric patients exposed to Armor-All Quicksilver Wheel Cleaner exhibited systemic toxicity including mental status changes, marked hypocalcemia, and ventricular fibrillation. One child also demonstrated profound hypomagnesemia. These are the first pediatric reports of near-fatal outcomes after ingestion or inhalation of a hydrofluoric acid-like product, namely, ammonium bifluoride.

PMID: 8953969 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8655406&dopt=Abstract

J Anat 1996 Feb;188 ( Pt 1):183-95

Structural changes in fluorosed dental enamel of red deer (Cervus elaphus L.) from a region with severe environmental pollution by fluorides.

Kierdorf U, Kierdorf H, Sedlacek F, Fejerskov O.

Royal Dental College, Faculty of Health Sciences, University of Aarhus, Denmark.

A macroscopic, microradiographic and scanning electron microscope study was performed on the structure of fluorosed dental enamel in red deer from a fluoride polluted region (North Bohemia, Czech Republic). As was revealed by analysis of mandibular bone fluoride content, the rate of skeletal fluoride accumulation in the fluorotic deer was about 6 times that in controls taken from a region not exposed to excessive fluoride deposition. In all fluorosed mandibles, the 1st molar was consistently less fluorotic than the other permanent teeth. This was related to the fact that crown formation in the M1 takes place prenatally and during the lactation period. Fluorosed teeth exhibited opaque and posteruptively stained enamel, reduction or loss of enamel ridges, moderately to grossly increased wear and, in more severe cases, also enamel surface lesions of partly posteruptive, partly developmental origin. Microradiographically, fluorosed enamel was characterised by subsurface hypomineralisation, interpreted as a result of fluoride interference with the process of enamel maturation. In addition, an accentuation of the incremental pattern due to the occurrence of alternating bands with highly varying mineral content was observed in severely fluorosed teeth, denoting fluoride disturbance during the secretory stage of amelogenesis. A corresponding enhancement of the incremental pattern was also seen in the dentine. The enamel along the more pronounced hypoplasias consisted of stacked, thin layers of crystals arranged in parallel, indicating that the ameloblasts in these locations had lost the distal (prism-forming) portions of their Tomes processes. The findings of the present study indicate that red deer are highly sensitive bioindicators of environmental pollution by fluorides.

PMID: 8655406 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8726823&dopt=Abstract

J Gastroenterol 1996 Jun;31(3):333-7

Gastroduodenal manifestations in patients with skeletal fluorosis.

Dasarathy S, Das TK, Gupta IP, Susheela AK, Tandon RK.


Department of Gastroenterology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India.

A prospective case-controlled study was performed to evaluate the gastrointestinal symptoms and mucosal abnormalities occurring in patients with osteofluorosis. Ten patients with documented osteofluorosis and ten age- and sex-matched healthy volunteers were included in the study. Clinical evaluation, real-time ultrasound, and upper gastrointestinal endoscopy and biopsy from the gastric antrum and duodenum were performed in all subjects. The biopsies were subjected to a rapid urease test and light and electron microscopic examinations. Ionic fluoride levels were estimated in the drinking water, serum, and urine using an ION 85 ion analyzer. All patients with osteofluorosis had gastrointestinal symptoms, the most common being abdominal pain. Endoscopic abnormalities were found in seven patients with osteofluorosis. In all 7 of these patients, chronic atrophic gastritis was seen on histology. Electron microscopic abnormalities were observed in all 10 patients with osteofluorosis. These included loss of microvilli, cracked-clay appearance, and the presence of surface abrasions on the mucosal cells. None of the control subjects had any clinical symptoms or mucosal abnormalities. It was concluded that gastrointestinal symptoms as well as mucosal abnormalities are common in patients with osteofluorosis.

PMID: 8726823 [PubMed - indexed for MEDLINE]


Fluoride 1996; 29(1):20-24

The effect of nutrition on the development of endemic osteomalacia in patients with skeletal fluorosis

Zang ZY (a), Fan JY (b), Yen W (b), Tian JY (c), Wang JG (a), Li XX (c), Wang EL (a)

(a) Anti-Epidemic Station in Baoding Region, Hebei Province, China
(b) Institute of Endocrinology, Tianjin Medical College, China
(c) Institute of Endemic Disease Prevention in Zhangjiako Region, China

Summary: The aim of the study was to study the relationship between nutrition and endemic osteomalacia, resulting in bone deformation with hump back, spinal curvature and "O" legs, in persons living in high drinking water fluoride areas with skeletal fluorosis. A dietary survey was made of 30-50 families from each of three villages in high fluoride areas of China, and in 273 persons in whom skeletal fluorosis was diagnosed clinically, clinical and radiological assessments were made for the presence of endemic osteomalacia with bone deformation together with malacia was found in persons with a lower intake of energy, protein, calcium and total protein. A hgher incidence of osteomalacia was found in persons with a lowerr intake of energy, protein, calcium and Vitamin C, particularly multiparous women. Poor nutrition was seen to be an important cause of endemic osteomalacia in high fluoride areas and that prevention would be aided by a better diet.


Fluoride 1996; 29(1):25-28

Skeletal change in osteofluorosis patients after defluoridation of drinking water

Meng XC, Chen PZ, Qin YP, Li HX

Shandong Provincial Institute of Endemic Diseases, Jinan, Shandong, China

Summary: Serial x-ray studies of cases of osteofluorosis over 12 years following defluoridation of drinking water show that signs of reversion may be seen as early as 4 and 5 years, and are found in all cases after 12 years, with a significant percentage reverting to an apparently normal state. Changes are found predominantly in cancellous bone.


Fluoride 1996; 29(1):29-32

CT examination of patients with osteofluorosis

PZ Chen and ZC Meng

Shandong Provincial Institute of Endemic Diseases, Jinan, Shandong, China

Summary: This paper reports CT (Computerized Tomography) scan findings of the examination of the vertebral canals of 12 patients with severe osteofluorosis diagnosed by x-ray and with typical signs of spinal nerve damage. The examination showed various degrees of ossification of the rear longitudinal ligament (RLL) (aka posterior longitudinal ligament) in all 12 cases and of the yellow ligament (YL) (aka ligamentum flavum) in 3 cases. Structure of the intervertebral foramen was found in one case. These results suggest that neurological findings indicative of spinal cord compression in patients with osteofluorosis are chiefly created by vertebral canal stricture caused by ossification of the RLL and YL rather than stricture of the canal by bone overgrowth. The CT scan clearly reveals the shape of the vertebral canal and the RLL and YL. Reconstruction of sagittal pictures may be used to localize the site of compression of the dural sac and nerve root, thereby obtaining results that can not be found by any other technique.


Fluoride 1996; 29(1):23-35

Lung x-ray changes in skeletal fluorosis caused by coal combustion

Bing-Kun Liu

Hubei Anti-epidemic and Sanitation Station, Wuhan, Hubei, China

Summary: Lung x-ray findings are reported in 45 cases with skeletal fluorosis in an area contaminated by coal combustion. The findings include chronic bronchitis, with diffuse interstitial fibrosis and pulmonary emphysema. The degree of pulmonary pathological findings and skeletal fluorosis is correlated with patient age. Among the 45 cases were 5 with cardio-pulmonary disease and 5 with tubeculosis.


Fluoride 1996; 29(2):59-62

The effects of fluoride, alone and in combination with selenium, on the morphology and histochemistry of skeletal muscle

Pang YX (a), Guo YQ (a), Zhu P (a), Fu KW (b), Sun YF (b)< Tang RQ (b)

(a) Department of Environmental Health Sciences, Public Health College, Harbin Medical University, Harbin, China
(b) Chinese Research Centre for Endemic Disease Control, Harbin, China

Summary: The objective was to study the effect of fluoride on skeletal muscle and the protection afforded by selenium. Skeletal muscle speciments from a four month old foetus were prepared for ultrastructural study after the addition of sodium fluoride, or sodium fluoride and sodium selenite, and incubation for two hours in vitro. Further specimens for ultrastructural and histochemical study were also obtained from rats who had been given, for eight weeks in vivo, drinking water containing 221 mg/L of sodium fluoride (100 ppm fluoride), or 221 mg/L of sodium fluoride and 16.7 mg/L of sodium selenite. The histochemical results showed a decrease in the activities of the enzymes succinate dehydrogenase, cytochrome oxidase, and Mg2+- adenosine triphosphatase when fluoride had been given. The ultrastructural studies showed that the skeletal muscle cells were damaged directly by fluoride with mitochondria and myofibrils being affected. Selenium was found to protect skeletal muscle from the effects of fluoride. It was concluded that skeletal muscle cells may be damaged by fluoride with necrosis following a disruption of energy metabolism in the mitochondria with interference to the stability of the mitochondrial membrane. Selenium was found to have a protective effect which may be due to improving mitochondrial membrane stability.


Fluoride 1996; 29(2):77-78

Fluorine, selenium, sulphur and carbon contents of coal in Hubei Province

MJ Li and SZ Tang

Sanitation and Anti-epidemic Station of Hubei Province, Wuhan, China

Summary: Analysis of 488 coal samples in Hubei Province for content of the elements fluorine, selenium, sulphur and carbon showed that the coal is of poor quality, low in C, high in ash and S, while F and Se contents are higher than the average for our country. The coal provides low heat energy. Fluorine and selenium toxicosis in Hubei is closely related to the combustion of this coal. Prevention and control measures are recommended to decreae the fluorine content in coal, and to renovate the coal-burning stoves in the area.


Fluoride 1996; 29(2):79-81

X-ray analysis of 80 patients with severe endemic fluorosis caused by coal burning

Zhao ZP, Yuan MB, Liu GF

Luzhou Medical College, Luzhou, Sichuan, China

Summary: Radiographs of 80 patients with severe endemic fluorosis of coal-burning type [CBEF] - 49 males and 31 females aged 30 to 70 years - were analysed to examine the changes to the bone substance, peripheral structure of bone, and joints. The changes to bone substance were:
1) osteosclerosis type, 62 cases (77.5%);
2) mixted type, 16 cases (21.25%);
3) osteoporosis type, one case (1.25%);
4) osteomalacia type, one case (1.25%).
The changes to the joints were : articular lesions were found in the hips and elbows in 79 cases (98.75%), and in the knees in 75 cases (93.75%). When combinations of the above three changes occur, the classification of the disease is according to the most severe one of the three. Our findings can increase the accuracy of x-ray diagnosis, making it more consistent with clinical diagnosis, thus improving prevention and treatment of CBEF.


Fluoride 1996; 29(2):82-88

Developments in the analysis of fluoride 1993-1995

Wen ML, Li QC, Wang CY

Department of Chemistry, Yunnan University, Kunming, China

This biennial review is a continuation of the previous articles [Fluoride 1994; 27(2):97-107 and Fluoride 1993; 26(3):197-202] and covers the literature of the analysis of fluoride from June 1993 to May 1995.


Fluoride 1996; 29(2):89-94

Thermodynamic analysis of airborne fluoride induced deterioration of marble and portland cement

R Shrivastav * and S Shrivastav

* Department of Chemistry, Dayalbagh Eductional Institute, Dayalbagh, Agra, India

Summary: Using thermodynamic data, the effect of airborne fluoride species (vapour-phase and precipitation) on the deteriortion of marble and Portland Cement has been estimated. Theoretically, for deterioration, the partial pressure thresholds of HF(g) and SiF4(g) required are on the order of 10-13-10-19 atm and 10-33-10-59 atm, respectively, whereas in rain water of pH 5.6, 10-14-10-27 M is the range of required equilibrium activity of HF2-(ag). Thermodynamic calculations show that the reactions of airborne species with marble and cement are possible in the atmosphere and that deteriortion is faster by the action of Hf(g) than SiF4(g). Moreover, acid deposition enhances the degree of atmospheric fluoride attack on marble and cement.


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8653387&dopt=Abstract
 
 
Chemosphere. 1996 Apr;32(8):1563-74.
 
Biodegradability of fluorinated surfactants under aerobic and anaerobic conditions.
 
Remde A, Debus R.
 
Fraunhofer-Institut fur Umweltchemie und Okotoxikologie, Schmallenberg, Germany.
 
The "ready biodegradability" of three fluorinated surfactants was determined under aerobic and anaerobic conditions. Surfactant 1, a solution of a fluorinated surfactant in water, was easily degradable under both aerobic and anaerobic conditions during the incubation periods of 28 and 60 days, respectively. Surfactant 2, a nonionic fluorinated surfactant, was degraded under aerobic conditions in a range of 35-77% during 28 days depending on the source of activated sludge. Aerobic degradation was inhibited by the nitrification-inhibitor dicyandiamide indicating that ammonium oxidizing bacteria may play a role in degradation of surfactant 2. Under anaerobic conditions surfactant 2 was not degraded. Surfactant 3, an anionic fluorinated surfactant, was degraded neither under aerobic nor under anaerobic conditions. Under anaerobic conditions, surfactant 3 inhibited the methane production rate of sludge from a digester. The EC50, i.e. the concentration of surfactant 3 that inhibited 50% of methanogenesis, was determined at 160 mg/l.
 
PMID: 8653387 [PubMed - indexed for MEDLINE]
 

Fluoride 1996; 29(2):95-96

Report of 15th Seminar of the Japanese Society for Fluoride Research, Sendai, Japan, November 14, 1995.

Kenji Akiniwa

Editor of Fluoride Research, journal of the Japanese Society for Fluoride Research, Tokyo, Japan.


Fluoride 1996; 29(2):99-100

Book Review

Fluoride in Dentistry (2nd Edition)

Ole Fejerskov, Jan Ekstrand and Brian A. Burt (Editors)

(Munksgaard, Cophenhagen 1996)

Reviewed by John Colquhoun

Excerpt: ... The chapters on dental fluorosis, the only toxic effect which the authors seem to acknowledge, are by contrast very good. Most interesting is the critique of the much-used Dean classification of dental fluorosis, as well as other early North American dental fluorosis studies. The authors conclude, from more recent evidence, that " ... even with very low fluoride intake from water, a certain level of dental fluorosis will be found" and " ... there exists no 'critical' value for the fluoride intake below which the effect on dental enamel will not be manifest. The conclusion reached by Hodge that dental fllluorosis will not occur at a water fluoride content below 1 ppm is therefore not tenable" (emphasis in the original)...


Fluoride 1996; 29(2):99-100

Book Review

The Greatest Fraud: Fluoridation

Philip RN Sutton

(Susan Sutton,PO Box 22, Lorne, Victoria 3232, Australia. 1996. $14 plus $11 postage)

Far from selecting and omitting research studies to suit his case, Sutton subjects every report which purports to prove a dental benefit from fluoridation to intense critical examination. Published after his death by his daughter-in-law, the book is, in effect, an updated version of his earlier classic, Fluoridation: Errors and Omissions in Experimental Trials. Indeed, Chapter 19 is a reprint of that earlier edition, which critically examined the first North American fluoridtation trials and is still relevant today, having stood the test of time. A later chapter makes further observations on those trials, while earlier chapters critically analyse and assess all succeeding pro-fluoridation studies, as well as criticisms of his analyses by proponents. Sutton's book will justify to many of his readers the change in title from the sedate "errors and omissions" to "the greatest fraud." It has become very apparent that, as Disendorf and others have pointed out in this journal, not a single study has ever been published which actually proves that fluoridation works.


Fluoride 1996; 29(4):193-201

Effect of parboiling on fluoride content of rice

A Anasuya and PK Paranjape

National Institute of Nutrition, Indian Council of Medical Research, Jamai Osmania, Hyderabad, India

Summary: In several endemic fluorotic zones of rural India, home-made parboiled rice is the main staple. Studies were therefore conducted to investigate whether any relationship exists between the concentration of fluoride in the water used for parboiling paddy, and in the parboiled rice.

Parboiled rice (PBR) was prepared in the laboratory using water from different origins (rivers, open wells, tube wells and ponds) collected from normal and fluorosis affected regions. The effect of (a) parboilding, (b) polishing, and (c) cooking, on the fluoride (F-) content of rice was studied, using two local varieties of paddy, namely, HANSA and SONA. Fluoride levels of PBR and raw rice collected from local markets of Hyderabad city were also measured.

Results show that:
1) parboiling paddy using water containing fluroide - either added or present originally - resulted in a significant increase in the F- content of the rice, irrespective of the source of water used;
2) this increase was directly proportional to the levels in F- in water (r = 0.96);
3) polishing PBR to 5% level reduced the F- content of rice by about 30%;
4) on cooking the PBR in the same source of water which was used for the parboiling, a cumulative 2- to 8-fold increase was observed in the F- content of the cooked PBR; and
5) even in the market samples, PBR had significantly more F- than raw rice.

This study reveals the importance of using only water with permissible limits of F- for parboiling and cooking. It also highlights the importance of food fluoride in the aetiology and control of endemic fluorosis


Fluoride 1996; 29(4):202-206

A study of water-borne endemic fluorosis in China

Teng GX, Zhaw XH, Shi YX, Yu GQ, Wang LH, Shen YF, Sun YF

Endemic Fluorosis Institute, Chinese Research Center for Endemic Disease Control, Harbin, China

Summary: Survey results are presented from 34 sentinel sites in 18 counties in endemic water-borne fluorosis areas of China through the years of 1991 and 1992. The progress in improving water to control fluorosis was very slow. By the end of 1991, only 42.1% of the villages, and 39.9% of the population, in endemic fluorosis areas had improved water supplies. In 1992 this improvement increasd by only 1%. Inspection of 987 water improvement projects to reduce fluoride showed that 82.7% were continuously used, 10.3% had interrupted use, and 7.0% had been stopped or destroyed. The projects resulted in 65.4% having a water fluroide content of less than 1.0 mg/L, 31.3% had 1.0-1.5 mg/L, and 15.4% had more than 1.5 mg/L. In 34 sentinel sites, urinary fluoride content and dental fluorosis indices of 8-12 year old children decreased year by year, especially in the sites with longer water improvement and water fluoride content less than 1.0 mg/L. Symptoms and signs of adult fluorosis also decreased, but not as significantly as the urinary fluoride content and dental fluorosis of children.


Fluoride 1996; 29(4):207-211

Coal burning induced endemic fluorosis in China

Y Zhang ad SR Cao

Institute of Environmental Health and Engineering, Chinese Academy of Preventive medicine, Beijing

Summary: Wide-spread coal-burning in Chna is caused by indoor combustion of high fluoride (F)-containing coal. The incidence of fluorosis increases with increase in the F content of coal. Indoor airborne F of fluorosis-afflicted areas exists mainly in a gaseous form (SiF4 and HF) with some co-existing aerosol forms. Gaseous F contributes about 40-80% of total inorganic F emission. Total airborne inorganic F was in the range of 11-155 ug/m3, several times higher than the National Hygienic Standards. Total F intake by adults in disease areas was found to be about 10 mg/day as compared to 0.8 mg/day in non-disease areas.


Fluoride 1996; 29(4):212-216

Assessment of fluoride removal from drinking water by calcium phosphate systems

GL He and SR Cao

He Gongli, Institute of Environmental Health and Engineering, Chinese Academy of Preventive Medicine, Beijing, China


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8968025&dopt=Abstract

Bone 1996 Dec;19(6):595-601

High fluoride intakes cause osteomalacia and diminished bone strength in rats with renal deficiency.

Turner CH, Owan I, Brizendine EJ, Zhang W, Wilson ME, Dunipace AJ.

Biomechanics and Biomaterials Research Center, Indiana University Schools of Medicine and Dentistry, Indianapolis 46202, USA. turnerch@indyvax.iupui.edu

Renal insufficiency is known to increase plasma fluoride levels
, which may increase the risk of fluorosis and osteomalacia. The purpose of this study was to determine the effects of fluoride on skeletal fragility and mineralization in renal-deficient animals. We evaluated the skeleton of rats with surgically induced renal deficiency (4/5 nephrectomy) that were chronically exposed to fluoridated water at concentrations of 0, 5, 15, and 50 ppm for a period of 6 months. The chosen fluoride doses caused plasma fluoride levels equivalent to those in humans consuming fluoridated water levels of 0, 1, 3, and 10 ppm, respectively. Animals with renal deficiency drank about 60% more water and excreted 85% more urine than control animals. Glomerular filtration rate (GFR) was decreased 68% and plasma BUN was increased fourfold in rats with renal deficiency. Plasma fluoride was strongly correlated with 1/GFR and was greatly increased by renal deficiency in all animals consuming fluoridated water. There was a strong positive, nonlinear relationship between plasma fluoride and bone fluoride levels, suggesting nonlinear binding characteristics of fluoride to bone. The amount of unmineralized osteoid in the vertebral bone was related to the plasma fluoride levels. Vertebral osteoid volume was increased over 20-fold in animals with renal deficiency that received 15 or 50 ppm fluoride, suggesting osteomalacia. Should osteomalacia be defined as a tenfold increase in osteoid volume, there appeared to be a threshold plasma fluoride level of about 20 micromol/L, above which osteomalacia was observed consistently. This plasma fluoride level was not achieved in control rats regardless of fluoride intake, nor was it achieved in renal-deficient rats receiving 0 or 5 ppm fluoride. A fluoride concentration of 50 ppm reduced femoral bone strength by 11% in control rats and by 31% in renal-deficient rats. Vertebral strength also was decreased significantly in renal-deficient rats given 50 ppm fluoride. In conclusion, fluoridated water in concentrations equivalent to 3 and 10 ppm in humans, caused osteomalacia and reduced bone strength in rats with surgically-induced renal deficiency.

PMID: 8968025 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8905000&dopt=Abstract

Allergy 1996 Oct;51(10):719-23

Allergen sensitization and exposure to irritants in infancy.

Soyseth V, Kongerud J, Boe J.

Hydro Aluminium Ardal, Ovre Ardal, Norway.

We investigated the relationship between residence in the neighbourhood of an aluminium smelter and the prevalence of atopy in schoolchildren (7-13 years of age). Atopy was assessed in 556 of the 620 participants by a skin prick test with eight common aeroallergens. The median exposures to sulphur dioxide and fluoride during the pollen season in the age interval 19-36 months were 24 and 3.1 micrograms/m3 in the spring and 20 and 3.3 micrograms/m3 in the summer, respectively. The odds ratio (OR) of having atopy was 2.0 (95% CI: 1.2-3.3) in those children who had lived in the index area for 7 years or more compared with those who had lived there less than 7 years (cumulative effect). The OR of atopy was 2.5 (1.4-4.4) in those who had lived in the index area during the age interval of 19-36 months compared with rural residence during this age-interval (age-specific effect). When the age-specific effect and the cumulative effect were compared in the same logistic model, the former decreased to 1.1 (0.4-3.0), whereas the latter was 2.2 (0.7-6.6). The results indicate that exposure to these low levels of irritants during early childhood increases allergen sensitization in children.

PMID: 8905000 [PubMed - indexed for MEDLINE]


Annales de Chirurgie de la Main et du membre Superieur 1996; 15(2):109-114

As cited and abstracted in Fluoride 1997; 30(2):124

Two cases of skeletal fluorosis in the hand

[article in French]

Sy MH, Sene P, Diouf MM, Diouf S

Reprints: Service d'Orthopedie et de Traumatologie, Centre de Traumatologie et d'Orthopedie de Dakar (CTO), BP 3270, Dakar, Senegal

Skeletal fluorosis is well known, particularly in the spine, pelvis and forearm. However, the hand may also be involved. The authors report two cases of this site in endemic areas in Senegal, after ingestion of large amounts of fluoride in the water. Fluorosis consisted of deforming metacarpal and phalangeal osteoperiotis in one case and peri-articular ossifications and calcifications of the attachments of the ligaments and capsule in the other case. They review the literature concerning skeletal fluorosis and discuss the rarity of hand involvement its clincial features and particularly its radiological fetures. Lastly, they emphasize the differential diagnosis with certain metabolic, infectious and neoplastic diseases.


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8722255&dopt=Abstract

J Wildl Dis 1996 Apr;32(2):190-8

Fluoride exposure and selected characteristics of eggs and bones of the herring gull (Larus argentatus) and the common gull (Larus canus).

Vikoren T, Stuve G.

Section for Wildlife Diseases, Central Veterinary Laboratory, Oslo, Norway.

Fluorine concentrations were determined in the shell of 285 herring gull eggs (Larus argentatus) and 120 common gull eggs (Larus canus), collected May 1991 to 1993, from breeding colonies exposed to emissions from two Norwegian primary aluminum smelters located at Karmoy and Sunndal, and from unexposed reference localities in Eigersund, Sola, and Stavanger. Volume-index, shell thickness, thickness-index, and fertilization of the eggs also were monitored. In both species, the shell fluorine concentration was significantly increased in eggs collected at sites exposed to fluoride emissions. No effects on other egg characteristics were observed. In both exposed and unexposed sites, the last-laid egg in a clutch, normally containing three eggs, had the highest shell fluorine residue. Fluorine levels also were analyzed in femurs from 42 herring gulls, collected from Karmoy and Sola in May 1993. The relationship between sex and fluoride accumulation, and the relations between fluorine concentration in femurs of laying herring gulls and in the shell of their eggs, were evaluated. Bone morphology also was studied. Bone fluorine concentrations were raised significantly in emission-exposed female birds. Moreover, females from the exposed site had significantly higher fluorine residues than males. There was a positive correlation between fluorine levels in femurs of individual laying birds and those in the shells of their eggs. No changes in bone morphology due to fluoride exposure was found.

PMID: 8722255 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8722254&dopt=Abstract

J Wildl Dis 1996 Apr;32(2):181-9

Fluoride exposure in cervids inhabiting areas adjacent to aluminum smelters in Norway. II. Fluorosis.

Vikoren T, Stuve G.

Section for Wildlife Diseases, Central Veterinary Laboratory, Oslo, Norway.

Mandibles from 1104 red deer (Cervus elaphus), 147 moose (Alces alces), and 453 roe deer (Capreolus capreolus), collected between 1990 and 1993 in the vicinity of seven Norwegian aluminum smelters, were examined for dental fluorotic and osteofluorotic lesions. The metacarpal or metatarsal bones from 214 of these cervids also were evaluated. Dental fluorotic lesions occurred in all three cervid species. Prevalence of dental fluorosis was generally low at the various locations, with the exception of Ardal, where 15% of the cervids examined were affected. Only sporadic cases of severe dental fluorotic lesions were diagnosed. All red deer yearlings (1.5 yr) with mandibular fluorine (F) levels exceeding 2,000 ppm F, had dental fluorosis. However, the lowest skeletal fluorine level found in a fluorotic animal of this age was 1,355 ppm F. Gross osteofluorosis occurred in only three cervids, all with mandibular fluorine residues > 8,000 ppm F. Hence, generalized fluorosis was not a prominent feature in the material studied.

PMID: 8722254 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8722253&dopt=Abstract

J Wildl Dis 1996 Apr;32(2):169-80

Fluoride exposure in cervids inhabiting areas adjacent to aluminum smelters in Norway. I. Residue levels.

Vikoren T, Stuve G, Froslie A.

Section for Wildlife Diseases, Central Veterinary Laboratory, Oslo, Norway.

Mandibular fluorine concentrations were determined in 1,425 red deer (Cervus elaphus), 240 moose (Alces alces), and 424 roe deer (Capreolus capreolus) collected in Norway from 1990 to 1993 in seven municipalities in which aluminum smelters are located, in eight neighboring municipalities, and in eight reference areas representing background levels. Background fluorine concentration was significantly correlated with age in all three species. Roe deer had the highest mean background fluorine level in each age group, followed by red deer. Due to differences in fluoride exposure, large variations in bone fluorine residues were evident between locations. In Ardal, the district most severely exposed to fluoride contamination, nine of ten cervids had fluorine concentrations exceeding background levels. The proportions of red deer with fluorine residues exceeding background levels also were high in neighboring municipalities to Ardal. We propose that roe deer are a better biomonitor of local fluoride exposure than red deer and moose, due to their more sedentary behavior.

PMID: 8722253 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8667313&dopt=Abstract

J Public Health Dent 1996 Winter;56(1):22-7

Comment in:


The risk of fluorosis in students exposed to a higher than optimal concentration of fluoride in well water.


Ismail AI, Messer JG.

Faculty of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada. ismaildl@ac.dal.ca

OBJECTIVES: In December 1991 the residents of the community of Rigolet, Labrador, Canada, discovered that they were exposed to higher than 2.0 ppm fluoride in the drinking water from the new town well, which became operational in December 1983. In 1993 an investigation of the occurrence of fluorosis in children exposed to the high-fluoride water during different ages of life was carried out.
METHODS: A dental examination for fluorosis was conducted using Pendrys' Fluorosis Risk Index. Out of 84 students in Rigolet, 74 were examined and the parents of 60 students agreed to be interviewed. Out of the 60 students, 48 lived all of their first six years of life in Rigolet.
RESULTS: Of the 48 children with life-long residence, the odds ratio of fluorosis on enamel zones that began forming during the first year of life was 8.31 (95% CI = 1.84, 38.59) for children exposed since birth or during the first year of life relative to those exposed after 1 year of age. The odds that a child had a maxillary central incisor with fluorosis were 5.69 (95% CI = 1.34, 24.15) times higher if exposure occurred during the first yea of life compared with exposure after 1 year of age. Only those exposed to the high-fluoride water during the first year of life developed fluorosis on the mandibular central incisors.
CONCLUSIONS: Within the limitations of this small population study, age relative to the date when the new water well became operational was a significant risk factor in development of fluorosis. The first year of life was a significant period for developing fluorosis on the mandibular and maxillary central incisors.

PMID: 8667313 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8737641&dopt=Abstract

Arzneimittelforschung 1996 May;46(5):531-3

Bioavailability of fluoride administered as sodium fluoride or sodium monofluorophosphate to human volunteers.

Rigalli A, Morosano M, Puche RC.

Laboratorio de Biologia Osea, Facultad de Ciencias Medicas, Rosario, Argentina.

This paper reports a reassessment of the bioavailability of fluoride from monofluorophosphate (MFP, CAS 10163-15-2). It was prompted by recent work from this laboratory reporting that, following an oral dose of MFP, a fraction of the drug appears in plasma bound to globulins forming a previously undetected compartment of non-diffusible fluoride. The presence of protein-bound MFP in plasma after the intake of this drug hinders its straightforward comparison with NaF (CAS 7681-49-4). After an oral of NaF, all plasma fluoride is diffusible. After intake of MFP, on the other hand, plasma contains diffusible fluoride and protein-bound fluoride during the 6-8 h following intake. The area under the curve of total plasma fluoride for MFP (1540 +/- 117 mumol.min/l) doubles that of NaF (811 +/- 52 mumol.min/l p < 0.001). On this basis, in agreement with findings previously reported for the rat, it is concluded that the bioavailability of fluoride for MFP doubles that of NaF.

Publication Types:

Clinical Trial

PMID: 8737641 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8740536&dopt=Abstract

Arch Toxicol 1996;70(7):420-9

Influence of fluoride on secretory pathway of the secretory ameloblast in rat incisor tooth germs exposed to sodium fluoride.

Matsuo S, Inai T, Kurisu K, Kiyomiya K, Kurebe M.

Department of Toxicology, School of Veterinary Medicine, University of Osaka Prefecture, Japan.

Fluoride, which is an environmental toxicant, is a potent inducer of mottled enamel in humans and rats. To define the influence of fluoride on the secretory pathway in enamel fluorosis, mottled enamel was induced in the incisor tooth germs of rats by subcutaneous injections of sodium fluoride for 4 days, and then morphological and cytochemical changes of the secretory ameloblast were examined in the tooth germs with HRP-labeled lectin (Con A, GS-I, SBA and PNA) and En3 antibody labeling amelogenins. The accumulation of small vesicles on the route of the secretory pathway between the rER and the Golgi apparatus, disorder of Golgi stacks, and formation of abnormal large granules in distal cytoplasm were seen in the secretory ameloblast. Lectin staining patterns of the secretory ameloblast indicated the disturbance of the vesicular transport between the rER and the Golgi apparatus, and disorganization of the Golgi stack. Immunolabeling of the cell showed disruption of the sorting and fusion process on the secretory pathway. These results suggest that the fluoride disturbs the intracellular transport in the synthesis-secretory pathway of the ameloblast, and that this effect of fluoride on the synthesis-secretory pathway participates in the formation of enamel fluorosis.

PMID: 8740536 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8609029&dopt=Abstract

Health Phys 1996 Mar;70(3):367-71

CaSO4:Dy and LiF:Mg, Cu, P thermoluminescent dosimeters for environmental monitoring in ambient areas of a nuclear power plant.

Zeng XS, Zeng JX, Tan GX, Mai WJ.

Guangdong Institute of Radiation Hygiene and Protection, Guangzhou, China.

This paper describes CaSO4:Dy and LiF:Mg, Cu, P which were used for ambient environmental monitoring before the nuclear power plant operation in Guangdong Daya Bay, China, in 1991. Since LiF:Mg, Cu, P was first used as an environmental dosimeter in this laboratory, the intercomparison of both thermoluminescent dosimeters, including laboratory irradiation and environmental exposure in Beijing reference spots, was conducted in cooperation with National Institute of Metrology and Laboratory of Industrial Hygiene, measured values of both thermoluminescent dosimeters were in agreement with the error being less than +or- 2% for the laboratory irradiation. The results of measurement by both thermoluminescent dosimeters were quite in agreement with environmental reference exposure rates measured by a pressurized ionization chamber. The largest error of CaSO4:Dy environmental monitoring results in Daya Bay also showed that the differences of measurement results between two thermoluminescent dosimeters were not significant. The experiment results indicated that LiF:Mg, Cu, P was a good environmental dosimeter.

PMID: 8609029 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9118877&dopt=Abstract

Environ Health Perspect 1996 Dec;104(12):1340-3

The relationship of fluorosis and brick tea drinking in Chinese Tibetans.

Cao J, Bai X, Zhao Y, Liu J, Zhou D, Fang S, Jia M, Wu J.

Tea and Health Research Laboratory, Hunan Medical University, Changsha, People's Republic of China.

Brick tea-drinking fluorosis is an unusual environmental problem. As a result of an investigation of tea-drinking habits, total fluoride intakes, dental fluorosis, and skeletal fluorosis, this disease has been found in the Sichuan Province of China in Tibetans with a long history of drinking brick tea. The dental fluorosis investigation of 375 Tibetan children (213 males, 162 females) and 161 Han children (86 males, 75 females), 8-15 years of age, was carried out in Daofu County, Sichuan Province. According to the standard of the Chinese Health Ministry, a skeletal fluorosis survey of 658 Tibetans (264 males, 394 females) and 41 Hans (20 males, 11 females), all over 16 years old, was performed. The total fluoride intake and fluorosis were determined from a question--calculation method in all participants. The morbidities of dental fluorosis in Tibetan and Han children are 51.2% and 11.05%, respectively, and the indexes of dental fluorosis are 1.33 and 0.17 (chi 2 = 75.7, p < 0.01) respectively. The morbidity of skeletal fluorosis is 32.83% for Tibetan children and zero for the Han children.
The fluoride intakes of Tibetan children and adults were 5.49 mg/person/day and 10.43 mg/person/day, respectively, in this area. Of total everyday fluoride intake, 94.2% by children and 94.4% by adults was from brick tea and zanba (r = 0.99).

PMID: 9118877 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8733628&dopt=Abstract

Bioorg Med Chem 1996 Mar;4(3):467-72

Difluoropalmitic acids as potential inhibitors of the biosynthesis of the sex pheromone of the Egyptian armyworm Spodoptera littoralis--IV.

Bosch MP, Perez R, Lahuerta G, Hernanz D, Camps F, Guerrero A.

Department of Technology of Tensioactives, C.I.D. (CSIC), Barcelona, Spain.

2,2-, 3,3- and 4,4-Difluoropalmitic acids (1-3) have been synthesized and fully characterized. Acids 2 and 3 were prepared through fluorination of the corresponding dithioacetal-protected ketoesters followed by enzymatic saponification. The acids 1-3 were evaluated in vivo as inhibitors of the beta-oxidation step of the biosynthesis of (Z,E)-9,11-tetradecadienyl acetate, the major component of the sex pheromone of the Egyptian armyworm Spodoptera littoralis. Only, the 2,2- and 3,3-derivatives, i.e. those containing the two fluorine atoms at the positions involved in the chain-shortened step, have been found to be active, the activity being similar to or lower than that displayed by the corresponding monofluorinated acids.

PMID: 8733628 [PubMed - indexed for MEDLINE]



Fluoride 1996; 29(4):241-251

Methods of monitoring smelter emission effects on a temperate rain forest

HWF Bunce

Forest Resource Consultants, Vancouver, Canada

Summary: Environmental effects of airborne emissions including fluroide from an aluminum smelter on a coniferous temperate rain forest in North America have been monitored since establishment of the smelter in 1954. Various methods used in measuring the effects of the emissions are described, along with summaries of the results as reported elsewhere.


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