The Stones' momentum sucked everyone, including themselves, into its vortex. "I decided that if Keith and I kept dipping into the same bag, there would be no book and we'd both be dead," writes Stanley Booth, one of the walking wounded of the rock 'n' roll wars, in the coda to his firsthand account of the Stones' infamous 1969 tour, Dance with the Devil. Booth puts a metaphysical shellac on the Stones' greed, while Philip Norman's Symphony for the Devil blandly passes off the Stones' saga of self-destruction as a saga of success. In both books the "devil" is a kind of glib folly, Neither author is prepared to see the moral and intellectual bankruptcy behind so much of their hard-driving rock 'n' rolling. The Stones' songs played at evil; but their lives embodied it. Evil is the inability to acknowledge the suffering of others. The destruction of life that seems to have followed the Stones is a barometer of their indifference. Illegitimate children are bom and forgotten. Their friends get hooked on drugs; some of them die. The Stones' lives were self-fulfilling prophecies of their songs. Their great early hit "I Can't Get No Satisfaction" (1965) announced the dilemma of their new wealth and fame: they were numb. The song was a blues by people who had everything:
Since the inception of the EHC Programme, the IPCS has organized meetings of scientists to establish lists of priority chemicals for subsequent evaluation. Such meetings have been held in: Ispra, Italy, 1980; Oxford, United Kingdom, 1984; Berlin, Germany, 1987; and North Carolina, USA, 1995. The selection of chemicals has been based on the following criteria: the existence of scientific evidence that the substance presents a hazard to human health and/or the environment; the possible use, persistence, accumulation or degradation of the substance shows that there may be significant human or environmental exposure; the size and nature of populations at risk (both human and other species) and risks for the environment; international concern, i.e., the substance is of major interest to several countries; adequate data on the hazards are available.
Hooked In Annus 1984 66
The main natural source of inorganic fluorides in soil is the parent rock (WHO, 1984). During weathering, some fluoride minerals (e.g., cryolite, or Na3AlF6) are rapidly broken down, especially under acidic conditions (Fuge & Andrews, 1988). Other minerals, such as fluorapatite (Ca5(PO4)3F) and calcium fluoride, are dissolved more slowly (Kabata-Pendias & Pendias, 1984). The mineral fluorophlogopite (mica; KMg3(AlSi3O10)F2) is stable in alkaline and calcareous soils (Elrashidi & Lindsay, 1986). However, its solubility is affected by pH and the activities of silicic acid (H4SiO4) and aluminium (Al3+), potassium (K+) and magnesium (Mg2+) ions.
Hydrogen fluoride (hydrofluoric acid) is an important industrial compound, with an estimated annual world consumption in excess of 1 million tonnes (Greenwood & Earnshaw, 1984). Hydrogen fluoride is manufactured from calcium fluoride and is used mainly in the production of synthetic cryolite, aluminium fluoride (AlF3), motor gasoline alkylates and chlorofluorocarbons; however, the demand for chlorofluorocarbons is decreasing as a result of efforts to restrict their use. Hydrogen fluoride is also used in the synthesis of uranium tetrafluoride (UF4) and uranium hexafluoride (UF6), both of which are used in the nuclear industry (Neumüller, 1981). It is also used in etching semiconductor devices, cleaning and etching glass, cleaning brick and aluminium and tanning leather, as well as in petrochemical manufacturing processes. Hydrogen fluoride may also be found in commercial rust removers (Upfal & Doyle, 1990).
In more acidic soils, concentrations of inorganic fluoride were considerably higher in the deeper horizons. The low affinity of fluorides for organic material results in leaching from the more acidic surface horizon and increased retention by clay minerals and silts in the more alkaline, deeper horizons (Davison, 1983; Kabata-Pendias & Pendias, 1984). This distribution profile is not observed in either alkaline or saline soils (Gilpin & Johnson, 1980; Davison, 1983). The fate of inorganic fluorides released to soil also depends on the chemical form, rate of deposition, soil chemistry and climate (Davison, 1983).
Calcium fluoride was formed in soils irrigated with fluoride solutions. Calcium fluoride is formed when the fluoride adsorption capacity is exceeded and the fluoride and calcium ion activities exceed the ion activity product of calcium fluoride (Tracy et al., 1984). Less than 2% of applied fluoride was measured in the leachate, and between 15 and 20% of added fluoride was precipitated as calcium fluoride. Fluoride was precipitated in the upper profile, although the authors expected that once the adsorption mechanisms were exceeded, soluble fluoride would leach deeper into the soil with continued irrigation.
Soluble fluorides are bioaccumulated by some aquatic and terrestrial biota. However, no information was identified concerning the biomagnification of fluoride in aquatic or terrestrial food-chains (Hemens & Warwick, 1972; Barbaro et al., 1981; ATSDR, 1993). Inorganic fluorides tend to accumulate preferentially in the skeletal and dental hard tissues of vertebrates, exoskeletons of invertebrates and cell walls of plants (Hemens & Warwick, 1972; Davison, 1983; Michel et al., 1984; Kierdorf et al., 1997; Sands et al., 1998).
Most fluorides enter plant tissues as gases through the stomata and accumulate in leaves. Small amounts of airborne particulate fluoride can enter the plant through the epidermis and cuticle (Weinstein, 1977). Vegetation has been widely monitored in the vicinity of anthropogenic emission sources of fluoride. Rice et al. (1984) obtained background fluoride concentrations for 17 plant species indigenous to the Northern Great Plains in the USA. Mean fluoride concentrations ranged from 1.5 to 3.3 mg/kg. Nine of these species were also monitored in polluted areas, and mean fluoride concentrations ranged from 2.8 to 11.3 mg/kg, with Rocky Mountain juniper (Juniperus scopulorum) accumulating the highest amounts of fluoride.
Walton (1984) monitored red foxes (Vulpes vulpes) in the United Kingdom and found mean bone fluoride concentrations ranging from 283 mg/kg at an unpolluted site to 1650 mg/kg near a smelter. There was a positive correlation between bone fluoride content and age.
In areas of the world in which endemic fluorosis of the skeleton and/or teeth has been well documented, levels of fluoride in groundwater supplies have been reported to range from 3 to more than 20 mg/litre (WHO, 1984; Krishnamachari, 1987; Kaminsky et al., 1990; US DHHS, 1991). In Tanzania, 30% of waters used for drinking-water contained fluoride at concentrations above 1.5 mg/litre, levels in the Rift Valley being up to 45 mg/litre (Latham & Gretch, 1967).
Since publication of the first EHC document on fluoride (WHO, 1984), additional information on the levels of fluoride in foodstuffs has become available. Virtually all foodstuffs contain at least trace amounts of fluoride. A summary of various studies in which the levels of fluoride in foods have been assessed is presented in Table 6.
Fluoride is mainly absorbed in the form of hydrogen fluoride, which has a pKa of 3.45. That is, when ionic fluoride enters the acidic environment of the stomach lumen, it is largely converted into hydrogen fluoride (Whitford & Pashley, 1984). Most of the fluoride that is not absorbed from the stomach will be rapidly absorbed from the small intestine.
In laboratory animals, the presence of food (Rao, 1984) and fluoride-binding ions (i.e., aluminium, calcium, magnesium) in the gastrointestinal tract (Spencer et al., 1981) significantly reduces the amount of fluoride absorbed into the general circulation. The absorption of ingested fluoride by female Wistar rats was reduced from 76 to 47% when the level of calcium in their diet was increased from 0.5 to 2% (Harrison et al., 1984). In male albino rabbits administered drinking-water containing 25 or 250 mg fluoride/litre (as sodium fluoride) for 4 weeks, the levels of fluoride in the serum (and femoral bone) were approximately 2-fold higher in animals administered a diet low in calcium (0.4%) than in controls administered a diet containing 1.6% calcium (Tsuchida et al., 1992).
Nephrotoxic effects produced in laboratory animals following acute oral exposure to fluoride have been reviewed (WHO, 1984). Subsequent studies have indicated that the severity of the acute renal toxicity of sodium fluoride in rats appears to be related to the age of the animal. In a study in which single doses of sodium fluoride (13.6 or 21.8 mg fluoride/kg body weight) were injected intraperitoneally into 1-, 8-, 15- or 29-day-old male and female Sprague-Dawley rats, proximal tubular necrosis and marked changes in kidney weight, urine osmolarity and pH, and chloride excretion were observed in the 29-day-old animals; effects in the younger animals were considered mild and less severe (Daston et al., 1985).
In laboratory animals, adverse effects within the gastrointestinal tract have been reported following the ingestion of acutely toxic doses of fluoride. In a study in which solutions of 1, 10 and 50 mmol fluoride/litre (as sodium fluoride dissolved in 0.1 N HCl) were introduced into the stomachs of anaesthetized female Wistar rats, histopathological effects on the gastric mucosa (i.e., desquamation of surface epithelial cells, cell loss and damage) were observed in animals administered 10 and 50 mmol/litre within 30 min of exposure (Easmann et al., 1984). Subsequently, Easmann et al. (1985) reported that following intubation of Holtzman rats with 1.5 ml of 100 mmol sodium fluoride/litre (approximately 17.8 mg fluoride/kg body weight), histopathological effects (i.e., haemorrhage, disruption of epithelial integrity and glandular structure, lysis and loss of epithelial cells) within the gastric mucosa were observed. After 48 h, there was recovery of gastric mucosal integrity. 2ff7e9595c
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