China
Africa
Explore chapters and articles related to this topic
Geoenvironment-Related Disease Endemicity in Africa, with Special Reference to Tanzania
Published in Jul Låg, Geomedicine, 2017
Though fluoride has been regarded as an essential element with an RDI level of 1.5 to 4.0 mg, excessive ingestion of the element will have deleterious consequences. Mottling of teeth and skeletal fluorosis (bow legs, knock-knees, stiffness of trunk, impeded movement of limbs, severe joint contraction, etc.) are attributed to the ingestion of more than 10 mg/ d of fluoride over several years. The incidence of skeletal fluorosis among workers in a cryolite factory in Denmark has been traced to their ingestion of fluoride dust. On the other hand, endemic fluorosis in Tanzania is confined to areas of high fluoride waters and arises from drinking such waters over the years.
Metals as a Cause of Contact Urticaria Syndrome
Published in Ana M. Giménez-Arnau, Howard I. Maibach, Contact Urticaria Syndrome, 2014
Majken G. Hougaard, Jacob P. Thyssen
The occurrence of occupational asthma in potroom workers has been documented in longitudinal [46] and cross-sectional [47] studies. Potroom workers are exposed to a complex mixture of particles and gases. The particles are mainly composed of aluminium oxide, carbon dust, and fluorinated compounds of sodium and aluminium called cryolite. It has been diffcult to identify the causal agent of potroom asthma. Fluoride compounds have been suggested to be the major candidates. The reported incidence of potroom asthma varies from 0.06% to 4% of exposed workers per year.[38] The most common clinical presentation of potroom asthma is a late reaction. The underlying mechanism is not fully understood.
Corrosives
Published in Bev-Lorraine True, Robert H. Dreisbach, Dreisbach’s HANDBOOK of POISONING, 2001
Bev-Lorraine True, Robert H. Dreisbach
Fluorine is used in organic synthesis. Hydrogen fluoride (hydrofluoric acid) is used in the petroleum and semiconductor industries and in etching glass. Cryolite (sodium aluminum fluoride) is used in aluminum reduction and many other industrial processes. Fluoride salts are used in the prevention of dental caries and in rodenticides. A 90 g tube of fluoride toothpaste contains 67 mg of fluoride. Methyl sulfonyl fluoride is used as a fumigant.
Fluoride exchange by glass-ionomer dental cements and its clinical effects: a review
Published in Biomaterial Investigations in Dentistry, 2023
John W. Nicholson, Sharanbir K. Sidhu, Beata Czarnecka
Both types of glass-ionomer are able to release fluoride once set [1,2]. Fluoride is present as a component of the glass. This is because the ionomer glass is made from a mixture that includes either calcite (CaF2) or cryolite (Na3AlF6) (see Table 1). These substances are present in the pre-firing glass mixture in order to lower the fusion temperature of the glass [12]. Glasses containing either of these substances can be melted at temperatures of around 1200 °C rather than in the region 1550–1600 °C, which would be necessary if they were not present [13]. Table 1 shows the pre-firing compositions of two significant ionomer glasses, G200, the first technically successful glass formulation, and G338, a widely studied formation that is close to most currently used ionomer glasses.
Vitamin C and E supplementation can ameliorate NaF mediated testicular and spermatozoal DNA damages in adult Wistar rats
Published in Biomarkers, 2022
Priyankar Pal, Ayan De, Tarit Roychowdhury, Prabir Kumar Mukhopadhyay
Epidemiological study demonstrated that humans, when suffered from skeletal fluorosis for long time also experienced with significant reduction of serum testosterone level (Susheela and Jethanandani 1996). Male infertility was also reported among married peoples in some endemic areas of India where the ground water fluoride concentration was 38.5 mg/L (Neelam et al.1987). Decreased serum testosterone level was also reported on Russian workers who were exposed to a fluorinated compound (cryolite) for more than 15 years (Ortiz-Pérez et al.2003). Animal experimentations with overexposed fluoride had also shown altered testicular histomorphometry, impaired spermatozoal status and tainted steroidogenesis (Cao et al.2016, Dong et al.2016). Another recent report states that fluoride is also responsible for altered activities of testicular functional markers along with loss of testicular genomic DNA integrity (Pal and Mukhopadhyay 2021). Abnormalities and reduction of capacitation ability of epididymal spermatozoa were also disparaging outcome due to fluoride mediated decreased tyrosin phosphorylation and actin polymerisation of spermatozoa (Dvoráková-Hortová et al.2008).
Effective early diagnosis for NSCLC: an algorithm
Published in Expert Review of Respiratory Medicine, 2021
Paul Zarogoulidis, Dimitris Matthaios, Christoforos Kosmidis, Wolfgang Hohenforst-Schmidt, Kosmas Tsakiridis, Sofia Mpaka, Ioannis Boukovinas, Dimitris Drougas, Vasiliki Theofilatou, Bojan Zaric, Nikolaos Courcoutsakis, George Nikolaidis, Haidong Huang, Chong Bai
The needles that are usually used with transthoracic convex probe are 18 G, the same with CT-guided biopsies. The sample is only tissue and it is stored in formole; however, 21 G and 22 G needles have both cells and small tissue fragments. The samples from these needles are stored in cytolite, and they need a special handling in order to convert the material to cell-blocks [52,53]. On the other hand, 19 G needles have more tissue sample; however, it is not possible to use them without taking additional safety risk for lesions ≤1 cm [54]. Forceps that are used through the bronchoscopy or EBUS acquire tissue samples and the material should be stored again in formole. Again, the material should be stored in cryolite. It is necessary for a center that uses the fine needle aspiration technique to have both a cytologist and a pathologist with experience in manipulating this kind of material. Figure 9 supplementary Cell blocks are sufficient for molecular investigation [55]. Figure 10 supplementary