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2000 Fluoride Abstracts. Part 2.
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Chemosphere. 2000 Nov;41(9):1451-5.
Heterogeneous photocatalytic decomposition of halosubstituted benzyl alcohols on semiconductor particles in aqueous media.
Wissiak KS, Sket B, Vrtacnik M.
Faculty of Natural Sciences and Engineering, Department of Chemical Education and Informatics, Ljubljana, Slovenia. katarina.wissiak@uni.lj.si
The photodegradation of 2-, 3- and 4-halosubstituted benzyl alcohols (HBAs) on semiconductive oxides (TiO2, ZnO) was studied. It was found out that the photodegradation rate increases from the fluoro to bromo derivates in the case of 2- and 4-HBAs, whereas in the case of 3-HBAs the reverse trend was observed.
PMID: 11057582 [PubMed - indexed for MEDLINE]
Full report available at http://www.fluoride-journal.com/00-33-1/331-33.pdfFluoride 2000; 33(1):33-38
Beneficial effect of tamarind ingestion on fluoride toxicity in dogs
Arjun L Khandare (a), P Uday Kumar, Nakka Lakshmaiah
(a) For correspondence: National Institute of Nutrition, Indian Council of Medical Research, Jamai Osmania PO, Hyderabad 500 007, Andhra Pradesh, India. Fax: 91-40-7019074. Email: icmrnin@ren.nic.in
SUMMARY: The effect of tamarind ingestion on fluoride retention was studied in three groups of dogs Ð control (Group I), fluoride-supplemented (Group II), and fluoride and tamarind-supplemented diets (Group III). The urinary excretion of fluoride was significantly higher in Group II (2.45 ± 0.39 mg F/day) and Group III (3.78 ± 0.35 mg F/day) as compared to Group I (0.205 ± 0.21 mgF/ day). The difference between Group II and III was also significant. The femur fluoride content of Group II animals (4.0 ± 0.67mg F/gm ash) was significantly higher as compared to that of Group III (2.0 ± 0.52 mg F/gm ash) suggesting a beneficial effect of tamarind ingestion on fluoride retention and toxicity.
There were no significant differences in hematological parameters between the groups, although hemoglobin levels and packed cell volume tended to be lower in Group III as compared to Group I. Histopathological study showed that except in kidneys where congestion and tubular changes were greater in experimental groups as compared to control, all other organs were comparable between the groups.
Report available at http://www.fluoride-journal.com/00-33-1/331-27.pdfFluoride 2000; 33(1):27-32
The influence of quercetin on some parameters of lipid metabolism in rats chronically exposed to ammonium fluoride
Czerny B *, Put A, Mysliwiec Z, Juzyszyn Z
* Department of Toxiclogy, Pomeranian Medical University, Szczecin, Poland
SUMMARY: Male Wistar rats were exposed to ammonium fluoride vapours in a toxicological chamber for 3 months. A mixture of sulfonic acid sodium salts of quercetin at a dose of 5 or 20 mg/kg body weight/24 h was given to some of the animals. It was found that quercetin salts alleviate changes in hepatic metabolism of lipids caused by ammonium fluoride
http://www.fluoride-journal.com/00-33-1/331-s1.pdfFluoride 2000; 33(1):S1
[XXIIIrd ISFR Conference abstracts, Szczecin, Poland, June 11-14 2000]
Fluoride in the environment and oral health in children
Adamowicz-Klepalska B, Krzyzag—rska J, Emerich-Poplatek K.
Dept of Pediatric Dentistry, Medical Univer of Gdansk, Poland.
Ecologists, toxicologists and physicians have devoted much attention to the problem of long-term exposure to high and to optimal concentrations of fluoride compounds in fresh water, air and food. Exposure to fluoride, combined with environmental factors, may markedly influence the health status of children during development and growth.
Zulawy is a depression in the Vistula delta near the Baltic Sea coast, which evolved during the Quaternary Period and where fluoride content in fresh water ranges from 1 .2 to 5 mg/L. The village of Wislinka in Zulawy is situated near a phosphorite waste depot, and its source of fresh water contains 1 .2 mg F/L.
The purpose of this study was to assess oral health status in 144 children aged 6-14, environmentally exposed to a high level of fluoride. The control group consisted of children from a region with a very low fluoride concentration in drinking water. Both groups were matched for age and gender. The examination protocol was based on the WHO Oral Assessment Form (1 987) and consisted of evaluation of dentition, gingiva, periodontium and oral hygiene. Status of dentition was evaluated with the index of dental caries (DMF), gingiva and periodontium with GI and CPITN, and oral hygiene with Pl I.
More than 83% of permanent teeth in children from Wislinka revealed mineralization defects, while in the control group the figure was 38%. Children in the high-fluoride group had 2.3 1 permanent teeth with a history of dental caries. Plaque Index values were similar in both groups (> 1 .0), but children from Wislinka had healthier gingiva (GI = 0.3) than controls (GI = 0.83).
http://www.fluoride-journal.com/00-33-1/331-s1.pdfFluoride 2000; 33(1):S2
[XXIIIrd ISFR Conference abstracts, Szczecin, Poland, June 11-14 2000]
Effects of sodium fluoride on bone mineral mass gain in growing rats
Bohatyrewicz A, Gusta A, Zietek P, Leznicka K
Dept of Orthopaedics and Traumatology, Pomeranian Academy of Medicine, Szczecin, Poland.
http://www.fluoride-journal.com/00-33-1/331-s1.pdfFluoride 2000; 33(1):S2-S3
[XXIIIrd ISFR Conference abstracts, Szczecin, Poland, June 11-14 2000]
Hardness of cortical bone in fluoride-treated growing rats
Bohatyrewicz A, Wysiecki M, Larysz D, Spoz A
Dept of Orthopaedics and Traumatology, Pomeranian Academy of Medicine, Szczecin, Poland.
http://www.fluoride-journal.com/00-33-1/331-s1.pdfFluoride 2000; 33(1):S5-S6
[XXIIIrd ISFR Conference abstracts, Szczecin, Poland, June 11-14 2000]
Longitudinal studies on the exposure to fluorides based on urine samples from infants living in Poznan
M Borysewicz-Lewicka 1, E Kaczmarek 2, E Gromadzinska-Zaplata 1, A Rydzewska 1, Swidzinska 1
1 Dept of Paediatric Dentistry, and 2 Dept of Medical Informatics and Statistics, K. Marcinkowski Univer of Medical Sciences, Poznan, Poland.
http://www.fluoride-journal.com/00-33-1/331-s1.pdfFluoride 2000; 33(1):S8-S9
[XXIIIrd ISFR Conference abstracts, Szczecin, Poland, June 11-14 2000]
An outline of possibilities of using fluoride-containing mine waste water for prophylaxis and therapy
M Ciosmak
Dept of Ecological Engineering, Technical University of Lublin, Lublin, Poland.
The aim of this article is to present possibilities of using mine waste water for prevention and therapy of some diseases. The water, containing significantly higher quantities of fluorine compounds, is drawn from Jurassic layers at a considerable depth. In the coal mine it combines with salty Carboniferous water and is pre-treated before being discharged to a river. Weakly mineralized Jurassic water with a fluoride content of 6-11 mg F/dm 3 can be used for pre-vention of dental and periodontal disease, particularly in risk groups. Fluoride contained in this water can be beneficial to patients after surgery or undergoing other treatment. Fluoride water from the Lublin Coal Basin can be helpful in bone disease, such as osteoporosis and fractures. According to the literature, reconstruction of normal osseous tissue is possible through balneotherapy. The water, free of harmful chemical compounds and micro-organisms, can be consumed (with controlled uptake of fluoride), used to wash the oral cavity, and for baths. However, the application of fluoride waters in children, due to their unstable metabolism, should be exercised with caution.
Full editorial available at http://www.fluoride-journal.com/00-33-2/332-49.pdfFluoride 2000; 33(2):49-51
Editorial
Fluoride and Intelligence
Bruce Spittle
Managing Editor: Fluoride, Dunedin, New Zealand
http://www.fluoride-journal.com/00-33-3/333-105.pdfFluoride 2000; 33(3):105-106
In Memoriam
Anne Catherine Anderson
1931 Ð 2000, Bellingham, Washington USA
Richard G. Foulkes, M.D. Abbotsford, B.C.
Excerpt:
Anne challenged me in 1991 to examine my acceptance of fluoridation as a safe and effective public health measure. With AnneÕs help scouring the resources of three regional university libraries, I was led to a complete reversal of my mindset on fluoridation. My initial belief was based on information given to me by those in authority rather than on the basis of my examination of the facts.
Anne spent the last ten years of her life challenging others and presenting the case for fluoride and fluoridation as serious hazards to human life and the environment. Anne attended ISFR Conferences in Kyoto, Beijing, Budapest and Bellingham. She was proud of being a founding member of The Fluoride Action Network and was especially pleased by the publication in Fluoride of our joint paper on the impact of fluoridation on salmon species in British Columbia, Canada and the US Pacific Northwest (Fluoride 1994 27:4;220-6).
Anne felt strongly that in a democracy, change is best brought about by letting politicians know that an informed public wants recognition that the issue is important to the constituent and worthy of action. To facilitate this process, Anne spent hours writing letters and on the telephone, at the copier, and fax-communicating her convictions. She testified three times in opposition to mandatory fluoridation before committees in Olympia, Washington State. She had frequent contact with State and Federal Representatives and Senators and once visited Washington DC to present the case against fluoridation to the Chairman of one of the key committees. She kept in touch with the officials of the city of Bellingham and Whatcom County and was one of those responsible for gaining support not only to keep Bellingham non-fluoridated but also to help defeat the State-sponsored mandatory Bills...
Full report available at: http://www.fluoride-journal.com/00-33-4/334-174.pdfFluoride 2000; 33(4):174-181
Fluoride in hair as an indicator of exposure to fluorine compounds
K Stolarska, W Czarnowski, B Urbaska, J Krechniak (a)
(a) For Correspondence: J Krechniak, Department of Toxicology, Medical University of Gda • sk, Al. Gen Hallera 107, 80-416 Gda • sk-Wrzeszcz, Poland. E-mail: eugeha@eniac.farmacja.amg.gda.pl
SUMMARY: Adult male Wistar rats were exposed to above-normal fluoride intake for 6 months: a) to HF by inhalation for 2 hr/day at a concentration of 8.7 ± 5.7 mg/m 3 and b) to sodium fluoride (NaF) in drinking water containing 20 mg F - /L. The fluoride content in dorsal hair, vertebrae L2 – L4, tibia, and incisors was significantly increased in the exposed animals. More fluoride accumulated by the inhalatory than by the oral route. Positive correlations were found between the fluoride content in bone and in washed hair (r = 0.696) as well as in unwashed hair (r = 0.647). The results of this study indicate that hair may be a useful indicator of long-term exposure to fluorine compounds.
Full report available at: http://www.fluoride-journal.com/00-33-4/334-196.pdfFluoride 2000; 33(4):196-204
Fluoride levels in hair of exposed and unexposed population in Poland
Zenon Kokot (a), Dariusz Drzewiecki (b)
(a) For Correspondence: Prof. Zenon Kokot, Ph. D., Department of Inorganic and Analytical Chemistry, K. Marcinkowski University of Medical Sciences, 6 Grunwaldzka Street, 60- 780 Pozna, Poland. E-mail: zkokot@mail.usoms.poznan.pl
(b) Regional Sanitary-Epidemiological Station in Ciechanów, Poland.SUMMARY: A microdiffusion procedure was used with a fluoride ion-selective electrode to determine fluoride levels in 548 hair samples collected in 1995- 1997 from children and adults living in the low-risk exposure region of Ciechanów, Poland. An additional 71 hair samples were collected from electrolysis workers with high-risk exposure at an aluminium plant in Konin, Poland. The mean hair fluoride values for the low-risk population varied from 1.3 to 2.6 µg/g (range <0.5 to 26 µg/g) and showed only small association with presumed exposure levels. Among the aluminium plant workers, the mean values were 403.4 and 2828.1 µg/g (range <113.7 to 5459.8 µg/g), and they exhibited a strong dependence on the type of work exposure to fluoride. Because hair samples are easily collected, fluoride in hair is a useful indicator of human fluoride exposure.
Full report available at: http://www.fluoride-journal.com/00-33-4/334-187.pdfFluoride 2000; 33(4):187-195
Endemic Genu valgum and other bone deformities in two villages of Mandla District in central India
T Chakma (a), P Vinay Rao, SB Singh, RS Tiwary
(a) For correspondence: Dr Tapas Chakma, Regional Medical Research Centre for Tribals, Indian Council of Medical Research, Jabalpur - 482 003, India. Email: tapaschakma@hotmail.com
SUMMARY: An epidemiological investigation was undertaken in the villages of Tilaipani and Hirapur located in Mandla District of Central India to determine the cause and extent of a peculiar skeletal deformity characterised by knock knee (genu valgum) occurring mainly among children. In Tilaipani, 74.4% of children and adolescents below age 20 had dental mottling, and 51.2% were afflicted with genu valgum. In Hirapur the figures were 56.9% and 6.25%, respectively. Radiological examination revealed extensive osteosclerosis with coarse trabecular pattern. In a few cases juxta-articular bone resorption, periosteal reaction, and bony exostoses were also present. Biochemical parameters were generally within normal limits, but dietary surveys indicated that calcium and vitamin C intakes were significantly below recommended levels. In Tilaipani the fluoride content of the drinking water ranged from 9.22 to 10.83 ppm and in Hirapur from below 1 ppm to 13.5 ppm. The mean urinary fluoride concentration in the cases of skeletal deformities was 4.42 ppm. The typical fluorotic dental mottling, the radiological findings, and the high fluoride content in the urine and drinking water all point to high fluoride, probably enhanced by deficient nutrition, as the cause of the genu valgum and other bone deformities.
Full report available at: http://www.fluoride-journal.com/00-33-4/334-205.pdfFluoride 2000; 33(4): 205-209
Fluoride concentrations in water sources in Tibet
Jin Cao (a), Yan Zhao, Jianwei Liu, Ruodan Xirao (b), Sangbu Danzeng (b)
(a) For Correspondence: Dr Jin Cao, Tea and Health Laboratory, Hunan Medical Univer-sity, Changsha, 4110078, Hunan, P.R. China. Email: caojin@public.cs.hn.cn;
(b) Research Institute of Prevention and Treatment of Endemic Diseases, Tibet, China.SUMMARY: Fluoride concentrations of 60 samples randomly selected from surface and underground water sources in major population regions of north-central, central, southern, and southern border regions of Tibet were determined with a fluoride-ion selective electrode. The concentrations ranged from 0.02 to 0.18 mg F/L with the highest levels in river and well waters. The results indicate that most drinking water sources in Tibet are low in fluoride and are therefore not responsible for the widespread occurrence of dental fluorosis that appears to be caused by early childhood intake of fluoride from high-fluoride “brick tea”.
Environ Res 2000 Jul;83(3):333-7
- As cited and abstracted in Fluoride 2000; 33(4):223
Environmental fluoride content in Tibet
Jin C, Yan Z, Jianwei L, Ruodeng X, Sangbu D
Tea and Health Laboratory, Hunan Medical University, Changsha, People's Republic of China. caojin@public.cs.hn.cn
As the first report of the environmental fluoride level in Tibet, the determination by the fluoride ion-seletive electrode method of fluorine concentration in water, soil, fuel, grains, food, vegetables, and tea was made for the Tibetan people living on various land types with various ecological characterics. The average level of fluoride concentration in water in Tibet was 0.06 mg/L; the level of dissolved fluoride in the soil was 0.45 mg/kg; the fluoride concentration in main fuels was 0.10 mg/k; the levels in main grains, food, and vegetables were 0.06-0.33 mg/kg; and water-dissolved fluoride concentrations in the brick tea produced in Sichuan Province and Yunan Province were 533.89-617.32 mg/kg. Tibet is the prevailing area of brick tea fluorosis.
Full report available at http://www.fluoride-journal.com/00-33-2/332-55.pdfFluoride 2000; 33(2): 55-65
Algal and cyanobacterial responses to fluoride
Monica Bhatnagar (a) and Ashish Bhatnagar Ajmer
(a) For correspondence: Department of Microbiology Kanad Vigyan Bhavan, Maharshi Dayanand Saraswati University, Ajmer (Rajasthan) India 305 009. Email: promicmon@yahoo.com, aridgabfa@hotmail.com
SUMMARY: This review deals with the distribution of fluoride tolerance between algae and cyanobacteria, their physiological response differences, and possible mechanisms of action of fluoride in these groups. Algae and cyano-bacteria differ in their response to fluoride, the latter being more sensitive to fluoride toxicity. The threshold concentration at which toxicity is manifested varies between organisms and is pH dependent. Being a strong hydrogen bonding species fluoride is capable of interacting with most of the cellular components and thus has a plethora of effects on cell metabolism.
Full report available at: http://www.fluoride-journal.com/00-33-2/332-66.pdfFluoride 2000; 33(2):66-73
A clinical and biochemical study of chronic fluoride toxicity in children of Kheru Thanda of Gulbarga District, Karnataka, India
AR Shivashankara (a), YM Shivaraja Shankara (a), S Hanumanth Rao (a), P Gopalakrishna Bhat (b)
(a) AR Shivashankara, Department of Biochemistry, M.R. Medical College, Gulbarga - 585 105, Karnataka, India.
(b) Department of Biochemistry, Kasturba Medical College, Manipal-576 119, Karnataka, India.SUMMARY: The prevalence of dental and skeletal fluorosis was determined among children of Kheru Nayak Thanda of Gulbarga district, where the fluoride concentration in drinking water ranges from 0.6 to 13.4 ppm and the water has low levels of copper and zinc. These children were investigated clinically, radiologically and biochemically. The study revealed that 89% of the children had dental fluorosis and 39% exhibited skeletal fluorosis. Serum samples of these children showed elevated levels of alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate transaminase (AST), and decreased levels of total protein, albumin, and potassium. Radiographic changes suggestive of osteoporosis, osteosclerosis, and genu valgum were observed.
Full report available at: http://www.fluoride-journal.com/00-33-3/333-121.pdfFluoride 2000; 33(3):121-127
Isopleth mapping and in-situ fluoride dependence on water quality in the Krishmagiri block of Tamil Nadu in south India
G Karthikeyan (a), A Shunmugasundarraj
SUMMARY: Drinking water samples from 255 villages in the Krishnagiri revenue block of Tamil Nadu in South India were analysed for fluoride and other water quality parameters. Fluoride endemic areas of the region were identified from the fluoride data and the prevalence of dental fluorosis. The high and low fluoride containing areas were located using the isopleth mapping technique. The dependence of fluoride on other drinking water quality parameters was assessed by simple and multiple correlation analysis.
a For Correspondence: Prof G Karthikeyan, M.Sc., Ph.D., Head of the Department of Chemistry, Gandhigram Rural Institute, Gandhigram 624 302, Dindigul District, Tamil Nadu, India. Phone: 91-451-452371. Fax: 91-451-452323. E-mail: gricc@md3.vsnl.net.in
Full report available at: http://www.fluoride-journal.com/00-33-3/333-135.pdfFluoride 2000; 33(3):135-139
Skeletal fluorosis from indoor burning of coal in southwestern China
Toshikazu Watanabe (a), Takashi Kondo (b), Shinji Asanuma (c), Mitsuru Ando (d), Kenji Tamura (e), Shiro Sakuragi (f), Ji Rongdi (g), Liang Chaoke (g)
(a) Toshikazu Watanabe, M.D., Saku Central Hospital, 197, Usuda, Usuda-machi, Minamisaku-gun, Nagano-ken 384-0301, Japan.
(b) Matsumoto Dental Col-lege, Shiojiri, Japan;
(c) Japan Institute of Rural Medicine, Usuda, Japan;
(d) National Institute for Environmental Studies, Tsukuba, Japan;
(e) National Institute for Minamata Disease, Minamata, Japan;
(f) Otsuma Women's University, Tama, Japan;
(g) Chinese Academy of Preventive Medicine, Beijing, China.SUMMARY: The effects of airborne fluoride from unvented indoor burning of fluoride-rich coal on the bones and teeth of residents of two rural villages in SW China were investigated and compared. In the highly polluted village of Xaochang in Sichuan Province, stage III skeletal fluorosis was found in 43 (84%) of 51 examinees. In the moderately polluted village of Minzhu in Guizhu Province, this stage was seen in 25 (51%) of 49 examinees. In the nonpolluted control village of Shucai in Jiangxi Province in SE China, none of 47 examinees showed any evidence of skeletal fluorosis. In Minzhu, but not in Xao-chang, significantly more males than females were afflicted with stage III skeletal fluorosis. In contrast with Xaochang, some examinees in Minzhu had serious skeletal effects but normal teeth or minor dental fluorosis. A high frequency of extremital transverse bone growth lines was observed in Xaochang but not in Minzhu. These findings suggest that greater exposure to fluoride occurred during infancy and early childhood in Xaochang than in Minzhu.
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Abstract from: http://www.fluoride-journal.com/01-34-1/341-71.pdfJ Public Health Dent 2000 Summer;60(3):167-71.
Low birth weight and dental fluorosis: is there an association?
Kumar JV, Swango PA
Bureau of Dental Health, New York State Department of Health, Albany, NY 12237-0619, USA. jvk01@health.state.ny.us
Objective: The association between low birth weight and dental fluorosis was explored in a cross-sectional study to explain the higher prevalence of dental fluorosis among African-American children.
Methods: Birth weight data on 960 children were obtained from the New York State Birth Registry. Data on race, fluoride exposure, sociodemographic characteristics, and dental fluorosis were available from a cross-sectional study conducted in Newburgh and Kingston. Associations among birth weight, race, and fluoride exposure from fluoridated water, regular use of supplements, brushing before the age of 2 years, and subject-level dental fluorosis were explored using logistic regression procedures.
Results: The regression coefficients for the main effects and the two-way interaction effects associated with low birth weight, race, and fluoride exposure were not statistically significant. Even after controlling for low birth weight and fluoride exposure, African-American children had a statistically significant higher odds ratio (OR = 2.0). An analysis of the data limited to mandibular permanent first molars showed similar effects, except for evidence of effect modification in low birth weight children exposed to fluoride supplements.
Conclusions: Lower birth weight did not explain the higher prevalence of dental fluorosis observed among African-American children.
Abstract from: http://www.fluoride-journal.com/01-34-1/341-71.pdfJ Public Health Dent 2000 Summer;60(3):131-9.
Fluoride intake and prevalence of dental fluorosis: trends in fluoride intake with special attention to infants.
Fomon SJ; Ekstrand J; Ziegler EE.
Department of Pediatrics, University of Iowa Hospitals and Clinics, Iowa City 52242-1083, USA. samfomon@aol.com
Background: Although the predominant beneficial effect of fluoride occurs locally in the mouth, the adverse effect, dental fluorosis, occurs by the systemic route. The caries attack rate in industrialized countries, including the United States and Canada, has decreased dramatically over the past 40 years. However, the prevalence of dental fluorosis in the United States has increased during the last 30 years both in communities with fluoridated water and in communities with nonfluoridated water. Dental fluorosis is closely associated with fluoride intake during the period of tooth development.
Methods: We reviewed the major changes in infant feeding practices that have occurred since 1930 and the changes in fluoride intakes by infants and young children associated with changes in feeding practices.
Results and conclusions: Based on this review, we conclude that fluoride intakes of infants and children have shown a rather steady increase since 1930, are likely to continue to increase, and will be associated with further increase in the prevalence of enamel fluorosis unless intervention measures are instituted. Recommendations: We believe the most important measures that should be undertaken are
(1) use, when feasible, of water low in fluoride for dilution of infant formulas;
(2) adult supervision of toothbrushing by children younger than 5 years of age; and
(3) changes in recommendations for administration of fluoride supplements so that such supplements are not given to infants and more stringent criteria are applied for administration to children.
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11860933&dopt=AbstractZhonghua Yu Fang Yi Xue Za Zhi 2000 Jul;34(4):215-7
[Direct effects of fluoride on activities of bone morphogenetic protein]
[Article in Chinese]
Xu S, Zheng G, Li M, et Al.
Institute of Environmental Medicine, Tongji Medical University, Wuhan 430030, China.
OBJECTIVE: To demonstrate the direct effects of fluoride on activities of bone morphogenetic protein (BMP).
METHOD: A complex sample containing BMP and sodium fluoride was implanted under the abdominal skin of young male Wistar rats. The histiological characteristcs, and activities of alkine phosphatase and acid phosphatase of the implantan were examined to study the effects of fluoride on biological activities of BMP.
RESULTS: More fibroblasts cell were transformed to osteoblats cell in animals treated by BMP with fluoride than those treated by BMP only. During bone formation induced by BMP, fluoride increased the acitivities of osteoblasts and accelerate mineralization, while inhibited the activities of osteoclast.
CONCLUSION: Fluoride can affect biological activities of BMP directly.
PMID: 11860933 [PubMed - in process]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11085424&dopt=AbstractJ Wildl Dis 2000 Oct;36(4):636-45
Fluorosis risks to resident hispid cotton rats on land-treatment facilities for petrochemical wastes.
Rafferty DP, Lochmiller RL, Kim S, Qualls CW, Schroder J, Basta N, McBee K.
Department of Zoology, Oklahoma State University, Stillwater 74078, USA. danielr@okstate.edu
Land-treatment of petroleum wastes is a widely used industrial practice, yet there has been no comprehensive evaluation of the long-term risks to human or terrestrial ecosystems from such practices. We evaluated cotton rat (Sigmodon hispidus) populations on three sites in Oklahoma (USA) that historically used land-treatment for disposal of various petroleum wastes (July 1995-March 1997). Average concentrations of fluoride in soil from these sites ranged from 878 to 4317 mg/kg. A census of resident cotton rats on land-treatment sites revealed a high incidence (40% overall) of dental lesions compared to reference populations (<1% dental lesions). During winter there was a 34% to 65% increase compared to summer in frequency of dental lesions in cotton rats on two of the three land-treatment sites. Incidence of dental lesions on two land-treatment sites was greater (9-16%) in female cotton rats compared to males. Cotton rats from land-treatment sites had higher concentrations of fluoride in bone and greater severity of dental lesions compared to reference animals. Dental lesions were considered to be most consistent with dental fluorosis because of elevated fluoride in bone. Neither concentration of fluoride in soil nor level of fluoride in bone was a good predictor of severity of dental lesions in cotton rats on land-treatment sites.
PMID: 11085424 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10615098&dopt=AbstractAm J Ind Med 2000 Feb;37(2):175-83
Cancer incidence and cause specific mortality among workers in two Norwegian aluminum reduction plants.
Romundstad P, Haldorsen T, Andersen A.
The Cancer Registry of Norway, Oslo. pr@kreftreg.no
BACKGROUND: Concern about the health hazards in the aluminum industry has initiated this study where we have investigated associations between exposure to polycyclic aromatic hydrocarbons (PAH) and fluorides, and cancer incidence and cause specific mortality among workers in two Norwegian aluminum plants in operation since 1954 and 1957, respectively.
METHODS: The study was designed as a historical cohort study and comprised 5627 identified men employed for more than six months. Cancer incidence was investigated from start of employment to 1995, and cause specific mortality was investigated from 1962 to 1995. The observed cases of cancers and observed deaths were compared with expected numbers calculated from national rates. Internal comparisons were made using Poisson regression with age and smoking included in the models. Historical exposure to PAH and fluoride had been estimated previously by use of statistical modeling on industrial hygiene measurements and process parameters. A job exposure matrix was used to investigate possible associations between cumulative exposures, and cancer incidence and cause specific mortality. Smoking habits were identified for 92% of the cohort members.
RESULTS: The study showed a significant excess risk for urinary bladder cancer among workers exposed to PAH, but no clear dose-response relationship. When using a 30-year lag period, a significant excess of bladder cancer in the highest exposure category (> 2000 microg/m(3);year PAH) was shown (SIR 4.08). The data also suggested an association between exposure to PAH and pancreatic cancer, but no association with lung cancer was seen. The mortality analysis indicated an association between exposure to pot-room emissions (fluorides) and mortality from chronic bronchitis, emphysema and asthma, but no associations with cardiovascular diseases.
CONCLUSIONS: The study findings are compatible with an excess risk for bladder cancer for aluminum plant workers exposed to PAH. The increased risk for cancer of the pancreas indicated, should be further evaluated in larger exposed populations. Copyright 2000 Wiley-Liss, Inc.
PMID: 10615098 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10810115&dopt=AbstractOccup Environ Med 2000 Apr;57(4):274-8
Increased nitric oxide in exhaled air: an early marker of asthma in non-smoking aluminium potroom workers?
Lund MB, Oksne PI, Hamre R, Kongerud J.
Department of Thoracic Medicine, The National Hospital, University of Oslo, Norway. m.b.lund@klinmed.uio.no
OBJECTIVES: To study exhaled nitric oxide (NO) as a marker of airway inflammation caused by potroom exposure, hypothesising that (a) workers exposed to potroom pollutants would have higher concentrations of NO in expired air than control subjects employed at the same plant but working outside of the potroom atmosphere, and (b) that concentrations of exhaled NO in potroom employees might be positively associated with concentrations of fluoride and exposure to dust.
METHODS: A study group comprising 186 male subjects (aged 24-63 years), employed in the potrooms of one Norwegian aluminium smelter, and 40 comparable control subjects (aged 25-60 years) recruited from the same plant, were examined by measurements of exhaled and nasal concentrations of NO, spirometry, and a questionnaire on respiratory symptoms as a part of an annual health surveillance programme. Estimates of exposure to fluorides and dust for selected job categories were obtained by means of personal samplers carried by the workers.
RESULTS: In the non-smokers, the concentrations of exhaled NO were higher in the potroom workers than in the controls (median (interquartile range) 9.3 (6.2-15.6) v 5.7 (4.6-8.3) ppb, p=0.001). The two groups did not differ in spirometry and asthma-like symptoms. Non-smoking potroom workers with asthma-like symptoms had higher concentrations of exhaled NO than those with no symptoms (median (interquartile range) 21.0 (19.3-41. 4) v 8.5 (5.9-12.8) ppb, p=0.001), but had comparable spirometric values. In subjects who smoked, the concentrations of exhaled NO did not differ significantly between potroom workers and controls (median (interquartile range) 4.6 (3.3-8.0) v 4.0 (3.4-5.1) ppb. Exhaled NO was not significantly associated with either duration of employment or routine measurements of dust and fluorides.
CONCLUSIONS: Exposure to potroom pollutants is associated with increased concentrations of exhaled NO in non-smoking subjects. Nitric oxide in exhaled air may be an early marker of airway inflammation in aluminium potroom workers.
PMID: 10810115 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11042093&dopt=AbstractToxicol Appl Pharmacol 2000 Nov 1;168(3):208-15
Pulmonary effects induced by ultrafine PTFE particles.
Johnston CJ, Finkelstein JN, Mercer P, Corson N, Gelein R, Oberdorster G.
Departments of Environmental Medicine, University of Rochester, Rochester, New York 14642, USA.
PTFE (polytetrafluoroethylene) fumes consisting of large numbers of ultrafine (uf) particles and low concentrations of gas-phase compounds can cause severe acute lung injury. Our studies were designed to test three hypotheses:
(i) uf PTFE fume particles are causally involved in the induction of acute lung injury,
(ii) uf PTFE elicit greater pulmonary effects than larger sized PTFE accumulation mode particles, and
(iii) preexposure to the uf PTFE fume particles will induce tolerance.
We used uf Teflon (PTFE) fumes (count median particle size approximately 16 nm) generated by heating PTFE in a tube furnace to 486 degrees C to evaluate principles of ultrafine particle toxicity. Teflon fumes at ultrafine particle concentrations of 50 microg/m(3) were extremely toxic to rats when inhaled for only 15 min. We found that when generated in argon, the ultrafine Teflon particles alone are not toxic at these exposure conditions; neither were Teflon fume gas-phase constituents when generated in air. Only the combination of both phases when generated in air caused high toxicity, suggesting either the existence of radicals on the surface or a carrier mechanism of the ultrafine particles for adsorbed gas compounds. Aging of the fresh Teflon fumes for 3.5 min led to a predicted coagulation to >100 nm particles which no longer caused toxicity in exposed animals. This result is consistent with a greater toxicity of ultrafine particles compared to accumulation mode particles, although changes in particle surface chemistry during the aging process may have contributed to the diminished toxicity. Furthermore, the pulmonary toxicity of the ultrafine Teflon fumes could be prevented by adapting the animals with short 5-min exposures on 3 days prior to a 15-min exposure. Messages encoding antioxidants and chemokines were increased substantially in nonadapted animals, yet were unaltered in adapted animals. This study shows the importance of preexposure history for the susceptibility to acute ultrafine particle effects. Copyright 2000 Academic Press.
PMID: 11042093 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11055010&dopt=AbstractBiomed Environ Sci 2000 Jun;13(2):90-6
Acute inhalation toxicity study of 2-fluoroacetamide in rats.
Singh M, Vijayaraghavan R, Pant SC, Sugendran K, Kumar P, Singh R, Purnanand.
Defence Research and Development Establishment, Gwalior, India. drde@gwrl.dot.net.in
One of the most potent rodenticides is 2-fluoroacetamide (2-FA). Toxicity of this chemical is well documented. However, its inhalation toxicity data is not available in the literature. Hence, acute inhalation toxicity study was carried out by exposing male and female rats to aerosols of 2-FA at different concentrations for 4 h in a dynamically operated whole body inhalation exposure chamber. During and after the inhalation exposure the rats were less active, and showed mild tremors and convulsions. At higher concentrations the rats died after 2-3 days. The estimated 4-h LC50 for male and female rats was 136.6 and 144.5 mg.m-3 respectively. Exposure to 0.7 LC50 for 4 h duration showed an increase in the liver weight of male and female rats 7 days after exposure. Various haematological and biochemical variables determined were within the normal limits. However, histological findings showed injured lung as indicated by desquamation and necrosis of the epithelium of the respiratory tract. Marked hypertrophy of hepatocytes displaying strong acidophilic granulated cytoplasm was observed. Focal dilatation of renal proximal tubules in kidney with cytoplasmic vacuolation, and irregularly placed pyknotic nuclei were seen. The present study shows that 2-FA is a highly toxic chemical through the inhalation route based on the LC50 value. Consequently necessary precautions should be taken during its handling.
PMID: 11055010 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11107641&dopt=AbstractVopr Pitan 2000;69(4):36-9
[Fluoroplastics: their properties, hygienic aspects and the possibility of their use in contact with food products]
[Article in Russian]
Khamidulin RS, Istomin AV, Khatiushina LP.
In the article the questions of fluoroplastes destruction, opportunity of migration in foodstuff non-polymerized monomers, additives and chemical substances formed as a result of thermal disintegration of polymer are considered.
Publication Types:
- Review
- Review, Tutorial
PMID: 11107641 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11205815&dopt=AbstractRes Rep Health Eff Inst 2000 Aug;(96):5-74; disc. 75-86
Acute pulmonary effects of ultrafine particles in rats and mice.
Oberdorster G, Finkelstein JN, Johnston C, Gelein R, Cox C, Baggs R, Elder AC.
Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, 575 Elmwood Avenue, Box EHSC, Rochester NY 14642, USA.
Ambient fine particles consist of ultrafine particles (< 100 nm) and accumulation-mode particles (approximately 100 to 1,000 nm). Our hypothesis that ultrafine particles can have adverse effects in humans is based on results of our earlier studies with particles of both sizes and on the finding that urban ultrafine particles can reach mass concentrations of 40 to 50 micrograms/m3, equivalent to number concentrations of 3 to 4 x 10(5) particles/cm3. The objectives of the exploratory studies reported here were to
(1) evaluate pulmonary effects induced in rats and mice by ultrafine particles of known high toxicity (although not occurring in the ambient atmosphere) in order to obtain information on principles of ultrafine particle toxicology;
(2) characterize the generation and coagulation behavior of ultrafine particles that are relevant for urban air;
(3) study the influence of animals' age and disease status; and
(4) evaluate copollutants as modifying factors. We used ultrafine Teflon (polytetrafluoroethylene [PTFE]*) fumes (count median diameter [CMD] approximately 18 nm) generated by heating Teflon in a tube furnace to 486 degrees C to evaluate principles of ultrafine particle toxicity that might be helpful in understanding potential effects of ambient ultrafine particles. Teflon fumes at ultrafine particle concentrations of approximately 50 micrograms/m3 are extremely toxic to rats when inhaled for only 15 minutes. We found that neither the ultrafine Teflon particles alone when generated in argon nor the Teflon fume gas-phase constituents when generated in air were toxic after 25 minutes of exposure. Only the combination of both phases when generated in air caused high toxicity, suggesting the existence of either radicals on the particle surface or a carrier mechanism of the ultrafine particles for adsorbed gas-phase compounds. We also found rapid translocation of the ultrafine Teflon particles across the epithelium after their deposition, which appears to be an important difference from the behavior of larger particles. Furthermore, the pulmonary toxicity of the ultrafine Teflon fumes could be prevented by adapting the animals with short 5-minute exposures on 3 days prior to a 15-minute exposure. This shows the importance of preexposure history in susceptibility to acute effects of ultrafine particles. Aging of the fresh Teflon fumes for 3.5 minutes led to a predicted coagulation resulting in particles greater than 100 nm that no longer caused toxicity in exposed animals. This result is consistent with greater toxicity of ultrafine particles compared with accumulation-mode particles. When establishing dose-response relationships for intratracheally instilled titanium dioxide (TiO2) particles of the size of the urban ultrafine particles (20 nm) and of the urban accumulation-mode particles (250 nm), we observed significantly greater pulmonary inflammatory response to ultrafine TiO2 in rats and mice. The greater toxicity of the ultrafine TiO2 particles correlated well with their greater surface area per mass. Ultrafine particles of carbon, platinum, iron, iron oxide, vanadium, and vanadium oxide were generated by electric spark discharge and characterized to obtain particles of environmental relevance for study. The CMD of the ultrafine carbon particles was approximately 26 nm, and that of the metal particles was 15 to 20 nm, with geometric standard deviations (GSDs) of 1.4 to 1.7. For ultrafine carbon particles, approximately 100 micrograms/m3 is equivalent to 12 x 10(6) particles/cm3. Homogeneous coagulation of these ultrafine particles in an animal exposure chamber occurred rapidly at 1 x 10(7) particles/cm3, so that particles quickly grew to sizes greater than 100 nm. Thus, controlled aging of ultrafine carbon particles allowed the generation of accumulation-mode carbon particles (due to coagulation growth) for use in comparative toxicity studies. We also developed a technique to generate ultrafine particles consisting of the stable isotope 13C by using 13C-graphite electrodes made in our laboratory from amorphous 13C powder. These particles are particularly useful tools for determining deposition efficiencies of ultrafine carbon particles in the respiratory tracts of laboratory animals and the translocation of particles to extrapulmonary sites. For compromised animals, we used acute and chronic pulmonary emphysema; a low-dose endotoxin inhalation aimed at priming target cells in the lung was also developed. Other modifying factors were age and copollutant (ozone) exposure. Exposure concentrations of the generated ultrafine particles for acute rodent inhalation studies were selected on the basis of lung doses predicted to occur in people inhaling approximately 50 micrograms/m3 urban ultrafine particles. Concentrations that achieved the same predicted lung burden per unit alveolar surface were used in rodents. (ABSTRACT TRUNCATED)
PMID: 11205815 [PubMed - indexed for MEDLINE]
Full report available at: http://www.fluoride-journal.com/00-33-4/334-159.pdfFluoride 2000; 33(4):159-167
Pulmonary effects of sodium fluoride aerosol on rats
Xue-Qing Chen (a,b), Kazuhiko Machida (b), Kaori Isizaki (b), Naomi Nisio (b), Mitsuru Ando (a)
(a) For correspondence: Xue-Qing Chen, Regional Environment Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-0053 Japan. Tel/Fax: +81-298-502395. E-mail: chen.xueqing@nies.go.jp;
(b) Department of Life Sciences, Graduate School of Human Sciences, Waseda University, Tokorozawa, Saitama, Japan.SUMMARY: Five-week-old male Fischer rats were exposed 3 hr per day for either 5 or 10 days to three concentrations of sodium fluoride aerosol (1.11, 3.33, and 10.3 mg F/m 3 ). A significant increase in lung weight was observed at the highest concentration. The activity of lactate dehydrogenase (LDH) and total protein concentration in bronchoalveolar lavage (BAL) fluid were also significantly higher in rats exposed to 3.33 and 10.3 mg F/m 3 . Neutrophil phagocytic activity in the blood was stimulated by 10-day exposure, and a significant increase in bactericidal activity and superoxide production was observed by exposure to 3.33 mg F/m 3 but not to 10.3 mg F/m 3 .
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11345680&dopt=AbstractMinerva Stomatol 2000 Nov-Dec;49(11-12):511-20
[Bio-metabolic changes produced by 2 commercial fluoride-containing compounds on human keratinocytes]
[Article in Italian]
Mattioli-Belmonte M, Sampalmieri F, Gabbanelli F, Principato G, Biagini G, Dolci G.
CIBAD-Centro Biomateriali Innovativi Istituto di Morfologia Umana Normale, Universita degli Studi, Ancona. belmonte@popcsi.unian.it
BACKGROUND: Although fluoride has been used for decades either systemically or topically to prevent dental caries, the cellular and molecular mechanisms underlying its action are poorly understood.
METHODS: An in vitro study of the human keratinocyte cell line NCTC 2544 was conducted in the presence of two different fluoride-containing commercial compounds (Zymafluor and Elmex) to investigate their toxicity threshold and the sequence of events involved in fluoride ion toxicity in this cell population. The toxicity threshold was determined by incubating cells with rising concentrations of Zymafluor and Elmex for 20 h. The study of the sequence of events involved in ion toxicity was performed through a time-effect study by exposing cells to 4 mM fluoride ions and testing them at 2, 6, and 20 h. Cell viability and ultrastructural parameters were assessed: degree of confluence, semiquantitative assessment of dead cells and debris in the supernatant, and morphology.
RESULTS: Ultrastructural morphological analysis showed different cell behaviours with the two compounds; moreover, their toxic effect appeared to be both concentration- and time-dependent.
CONCLUSIONS: These data underline the susceptibility of the intracellular communication system to fluoride and show that exceeding the therapeutic dose of fluoride involves substantial risk of toxicity.
PMID: 11345680 [PubMed - indexed for MEDLINE
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11326509&dopt=AbstractJ Esthet Dent 2000;12(2):97-104
Effect of alcoholic and low-pH soft drinks on fluoride release from compomer.Abu-Bakr NH, Han L, Okamoto A, Iwaku M
Department of Operative Dentistry and Endodontics, Niigata University School of Dentistry, Niigata, Japan. neamat@dent.niigata-u.ac.jp [Medline record in process]
PURPOSE: The purpose of this study was to evaluate the amount of fluoride released from compomer restorative materials after immersion in various media.
MATERIALS AND METHODS: In this test, four materials were used: three compomers (Dyract, Dentsply, Konstanz, Germany; Compoglass, Vivadent, Schaan, Principality of Liechtenstein; and Xeno, Sankins, Tochigi, Japan) and one resin-modified glass ionomer cement (Fuji II LC, GC, Tokyo, Japan). There were four test solutions: one alcoholic (whiskey), two low-pH drinks (Coca-Cola, orange juice), and one deionized water. Over a period of 60 days, the tested specimens were immersed in the test solution for 3 hours every day, then kept in deionized water. The fluoride released was detected by using a fluoride ion selective electrode connected to a microprocessor ion analyzer. The fluoride ion concentration (ppm) of the test solutions and deionized water was recorded after 1, 2, 3, 4, 7, 30, and 60 days. Electron probe microanalysis was used for surface analysis of the fluoride released.
RESULTS: When immersed in low-pH soft drinks, compomer showed a significantly higher fluoride release than when immersed in deionized water (p < .0001). For specimens immersed in Coca-Cola, the fluoride release levels (microgram/cm2, mean +/- SD) at 1, 7, and 60 days for Dyract (91.6 +/- 1.8, 39.3 +/- 3.1, 10.5 +/- 0.9), Compoglass (129.5 +/- 0.9, 66.5 +/- 2.7, 19.0 +/- 0.3), Fuji II LC (147.0 +/- 4.2, 50.8 +/- 3.1, 27.6 +/- 3.0), and Xeno (73.6 +/- 3.2, 27.3 +/- 2.1, 6.6 +/- 0.6) demonstrated the trend of significantly lower releases with time in water solution. Over a 60-day period, materials immersed in 100% orange juice released the highest amount of fluoride, which could be attributable to the erosive effect of the medium. Materials immersed in deionized water released the least amount of fluoride. Among the tested compomers, Compoglass released the most fluoride.
PMID: 11326509, UI: 21224447
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10915622&dopt=AbstractScience 2000 Jul 28;289(5479):611-3
A potent greenhouse gas identified in the atmosphere: SF(5)CF(3)
Sturges WT, Wallington TJ, Hurley MD, Shine KP, Sihra K, Engel A, Oram DE, Penkett SA, Mulvaney R, Brenninkmeijer CA.
School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK. Ford Motor Company, Mail Drop SRL-3083, Dearborn, MI 48121-2053, USA. Department of Meteorology, University of Reading, Reading RG6 6BB, UK. Institute for Meteorology.
We detected a compound previously unreported in the atmosphere, trifluoromethyl sulfur pentafluoride (SF(5)CF(3)). Measurements of its infrared absorption cross section show SF(5)CF(3) to have a radiative forcing of 0.57 watt per square meter per parts per billion. This is the largest radiative forcing, on a per molecule basis, of any gas found in the atmosphere to date. Antarctic firn measurements show it to have grown from near zero in the late 1960s to about 0.12 part per trillion in 1999. It is presently growing by about 0.008 part per trillion per year, or 6% per year. Stratospheric profiles of SF(5)CF(3) suggest that it is long-lived in the atmosphere (on the order of 1000 years).
PMID: 10915622 [PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10556379&dopt=AbstractArch Environ Contam Toxicol 2000 Jan;38(1):121-7
The fluoride content of antlers as an indicator of fluoride exposure in red deer (Cervus elaphus): A historical biomonitoring study.
Kierdorf U, Kierdorf H.
Institute of General and Systematic Zoology, Justus-Liebig-University of Giessen, Stephanstrasse 24, D-35390 Giessen, Germany.
Bone fluoride concentrations were analyzed in 141 red deer antlers grown between the 17th/early 18th century and 1997, that originated from four study areas (Arnsberg, Bad Berleburg, Dammerwald, Schmidtheim) in the federal state of North Rhine-Westphalia, Germany. Fluoride concentrations in the specimens ranged between 27.7 and 1, 392.1 mg F(-)/kg ash and varied significantly both between samples collected during different time-spans in the same area and between samples taken from different study areas over the same period. For antlers (n = 8) collected prior to 1860 in the study areas Arnsberg and Schmidtheim, values between 27.7 and 78.7 mg F(-)/kg ash were recorded. It is assumed that antler fluoride contents in this range are quite close to baseline levels for these regions, i.e., represent concentrations largely unaffected or only slightly influenced by fluoride from anthropogenic sources. With the onset and expansion of large-scale industrial activities, bone fluoride concentrations in the antler samples markedly increased over these baseline values, indicating fluoride deposition from industrial emissions into the red deer habitats. In the later 1980s and the 1990s, a pronounced decline in antler fluoride content was observed, which is attributed to the reduction of industrial fluoride discharges due to effective emission control programs. However, even the lowest fluoride values recorded for antlers grown in the 1990s (study area Schmidtheim, n = 10, range 158.5-367.3 mg F(-)/kg ash) clearly exceeded the concentrations found in the antlers collected prior to 1860, thereby indicating an additional fluoride burden from anthropogenic sources on the recent populations. The present study has corroborated the view that antlers are good indicators of fluoride exposure in deer. The facts that they grow during a seasonally fixed time-span and thus constitute relatively well "naturally standardized" samples and are often kept over long periods of time make antlers suitable monitoring units for historical biomonitoring studies.
PMID: 10556379 [PubMed - indexed for MEDLINE]
J Anat 2000 Jan;196 ( Pt 1):71-83
- As cited and abstracted in Fluoride 2000; 33(2):93-94
Structure and mineralisation density of antler and pedicle bone in red deer (Cervus elaphus L.) exposed to different levels of environmental fluoride: a quantitative backscattered electron imaging study
Kierdorf U, Kierdorf H, Boyde A
Institute of General and Systematic Zoology, Justus-Liebig-University of Giessen, Germany. kierdorf@lindlar.de
The structure and relative degree of mineralisation of antler and pedicle bone of yearling red deer stags exposed either to low or high levels of environmental fluoride were determined by digital quantitative backscattered electron (BSE) imaging. Bone fluoride content (BFC) in antlers (845 ± 86 mg F - /kg ash, arithmetic mean ± S.E.M.) and pedicles (1448 ± 154 mg F - /kg ash) of deer from a highly fluoride polluted area in North Bohemia (Czech Republic) were significantly higher (P <0.001) than those of controls from uncontaminated regions in West Germany (antlers: 206 ± 41, pedicles: 322 ± 52 mg F - /kg ash). Mean (56.5 ± 4.5%) and maximum (84.9 ± 2.1%) mineralised bone area of the control antlers significantly (P <0.05 and P <0.001, respectively) exceeded the corresponding values for the N. Bohemian deer (43.3 ± 1.3 and 73.3 ± 1.9%, respectively), while the pedicles from the 2 groups did not differ significantly. In the pooled antler samples (n = 18), negative correlations existed between BFC and mean (r(s) = -0.62, P <0.01) as well as maximum (r(s) = -0.69, P <0.01) mineralised bone area. Morphological imaging revealed a decreased width and an increased porosity of the antler cortex in the N. Bohemian speci-mens. Mean (148.5 ± 1.7) and maximum (154.2 ± 1.7) BSE-signal intensities (= grey levels; range between a monobrominated (grey level 0) and a monoio-dinated (grey level 255) dimethacrylate resin standard) of the antlers from the controls were significantly higher than those of the N. Bohemian deer (140.7 ± 2.1 and 145.7 ± 2.2, respectively; P <0.05 for both comparisons). In the pooled antler samples, negative correlations between BFC and mean (r(s) = -0.51, P <0.05) as well as maximum (r(s) = -0.52, P <0.05) BSE-signal intensities were observed. No significant differences in mineralisation density parameters were found for the 2 pedicle samples, and BFC and mineralisation density of the pooled pedicles were uncorrelated. Morphological imaging revealed bone mottling (denoting increased remodeling activity) and frequent occurrence of apparently increased osteocyte lacunae in some of the pedicles from the N. Bohemian deer. It is concluded that the reduced amount of mineralised bone in, and the lower mineralisation density of, the N. Bohemian antlers resulted from a fluoride induced disturbance of bone mineralisation. The rapid growth of antlers leads both to a high mineral demand and a high rate of fluoride uptake during antlerogenesis. This, and the limited lifespan of antlers, which does not allow for a compensation of a delay in the onset or progression of the mineralisation process, renders antler bone particularly susceptible to fluoride. Antlers are therefore considered a useful model for studying fluoride effects on bone formation. Furthermore, analysis of cast antlers enables a noninvasive moni-toring of environmental pollution by fluorides.
J Air Waste Manag Assoc 2000 Jan;50(1):137-41
- As cited and abstracted in Fluoride 2000; 33(2):94
Sulfur hexafluoride: global environmental effects and toxic byproduct formation
Dervos CT, Vassiliou P
Department of Electrical and Computer Engineering, National Technical University of Athens, Greece. cdervos@central.ntua.gr
This work provides information concerning possible global environmental implications and personnel safety aspects that should be considered during the commercial uses of sulfur hexafluoride (SF6). SF6 is an anthropogenically produced compound, mainly used as a gaseous dielectric in gas insulated switch-gear power installations. It is a potent greenhouse gas with a high global warming potential, and its concentration in the earth atmosphere is rapidly increasing. During its working cycle, SF6 decomposes under electrical stress, forming toxic byproducts that are a health threat for working personnel in the event of exposure. Several precautions are recommended to avoid personnel exposure to toxic byproducts: oxyfluoride levels or other byproduct concentrations in the operating gas matrix should be traced to predetermine the overall gas toxicity; contaminants should be systematically considered during maintenance, chamber evacuation and system opening process; small SF6 quantities leaking into air or stagnated pollutant concentrations in the operating field should be analyzed and compared to the threshold limit values and permissible exposure levels. New system design rules (i.e., hermetically sealed gas compartments, gas recycling or disposal in the field area) and different handling policies Ð both during maintenance and final disposal Ð now should be consid-ered globally to provide for environmental and personnel safety.
AIHAJ 2000 Jan-Feb;61(1):89-94
- As cited and abstracted in Fluoride 2000; 33(2):95
Urinary fluoride as an exposure index in aluminum smelting
Seixas NS, Cohen M, Zevenbergen B, Cotey M, Carter S, Kaufman J
Department of Environmental Health, University of Washington, Seattle 98195-7234, USA
Urinary fluoride was evaluated as an exposure index for a prospective study of asthma in an aluminum smelter. Two studies were conducted to evaluate the relationship between airborne exposure and urinary excretion over a work-week, and to describe exposures among jobs and over time. Thirty-two subjects were evaluated on Days 1 and 3 of a 3-day workweek. On each day, spot urine samples were collected prior to the start of work and again at the end of the shift. Samples were analyzed for fluoride and expressed as milligrams fluoride per gram of creatinine. Airborne exposures to total particulate, fluoride particulate, and hydrogen fluoride (HF; using a 37-mm filter cassette containing a filter and treated back-up pad) were also evaluated on each subject. In the second study, postshift urine samples were collected from asthma study volunteers in three surveys extending over 1.5 years and analyzed for fluoride. Average airborne exposures were 15.7, 4.1, and 0.7 mg/m 3 for particulates, particulate fluorides and HF, respectively, and were substantially higher among carbon setters than other workers. However, average urine fluorides among the same workers were reasonably low, 1.3 and 3.0 mg/g creatinine in pre- and postshift urine samples, respectively. Carbon setters, who routinely wore respiratory protection during high exposure periods, had urinary fluoride levels similar to those of other potroom personnel. A significant variation in dose, as expressed by postshift urinary fluoride levels, was observed between potroom and non-potroom jobs and over three survey periods. These results suggest that postshift urinary fluorides provide a reasonable exposure index for surveillance of exposure levels for an epidemiologic study, and that a substantial variation of exposure occurs between jobs and over time. Although urinary fluorides may be used for exposure surveillance, additional details on individual exposure agents and patterns of exposure over time are required for complete assessment.
Japanese Journal of Fluoride Research 2000: 19:1
- As cited with full translation in Fluoride 2001; 34(2):157158
Tribute to John Yiamouyiannis
Tohu Murakami, DDS, PhD, Editor
Acta Odontol Scand 2000 Feb;58(1):1-7
- As cited and abstracted in Fluoride 2000; 33(2):90-91
Urinary fluoride excretion by children 4-6 years old in a south Texas community
Baez RJ, Baez MX, Marthaler TM
Dental School, Department of General Dentistry, University of Texas Health Science Center at San Antonio. baez@uthscsa.edu
This study evaluated urinary fluoride excretion by school children 4-6 years old who were living in a south Texas rural community that had concentrations of fluoride in drinking water supplies generally around the optimal level. We took supervised collections of urine samples in the morning and afternoon at school, and parents of the participating students collected nocturnal samples. We recorded the beginning and end times of the three collection periods and then determined the urinary volume and urinary flow for each of the periods. We measured urinary fluoride concentrations and calculated the urinary excretion rate per hour. The children had breakfast and lunch provided at the school, where the drinking water contained 1.0-1.3 milligrams/liter (mg/L) fluoride. Fluoride concentrations in the tested household water supplies, from wells, ranged from 0.1 to 3.2 mg/L fluoride. The children's average urinary fluoride concentrations found for the day were similar to those for the night, with means ranging from 1.26 mg/L to 1.42 mg/L. Average excretion was 36.4 µ/h in the morning, 45.6 µ/h in the afternoon, and 17.5 µ/h at night. The lower nocturnal excretion rates are easily explained by low urinary flow at night. Based on the 15 hours of urine collected, the extrapolated 24-hour fluoride excretion was 749 µ. In conjunction with similar studies, the data from this study will help in developing upper limits for urinary fluoride excretion that are appropriate for avoiding unsightly fluorosis while providing optimal protection against dental decay.
Appl Occup Environ Hyg 2000 Apr;15(4):354-61
- As cited and abstracted in Fluoride 2000; 33(2):92-93
Personal fluoride and solvent exposures, and their determinants, in semiconductor manufacturing
Woskie SR, Hammond SK, Hines CJ, Hallock MF, Kenyon E, Schenker MB
Department of Work Environment, University of Massachusetts Lowell, USA
Personal air sampling for fluorides and solvents was done at 35 semiconductor fabrication facilities in the United States. Fluoride compounds were used in etching and cleaning operations, and solvents were used in photoresist and developing operations. All personal solvent and fluoride levels were less than 2 percent of current Occupational Safety and Health Administration (OSHA) standards. Statistical models of the exposure determinants for the target agents found production level, as indicated by number of semiconductor wafer cassettes loaded/unloaded from the target machines or baths, was predictive of fluoride, xylene and 1-methoxy-2-propyl acetate exposures. The percent of fresh air ventilation and the percent of xylene in the photoresist were also significant determinants in the statistical model predicting personal xylene exposure levels.
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