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Background: northern Chile has the highest levels of lithium in surface waters in the world which is reflected in very high lithium levels in the plants and animals that depend on these water systems and consequently in the indigenous population.Methods: the lithium tissue burdens in populations from two valleys in the extreme north of Chile have been studied. The bulk of this report is based on analyses of lithium levels in urine, hair, and breast milk in the population of several villages. Data on serum levels, some of which had been previously published, are included for the sake of completeness. Since this paper reports studies by several groups of workers samples were analysed by a variety of methods. These include atomic emission, atomic absorption, other photospectroscopic techniques and mass spectroscopy.Results: in all samples studied the average lithium level (5.3 ppm) was found to be significantly elevated compared to levels reported in the literature and measured in this study for people not exposed to high levels in water and food (0.009-0.228 ppm).Conclusions: the people studied represent a unique longitudinal cohort. The work should provide important insights into the potential neuroprotective effects of lithium also help us set guidelines to assess the risks from high dose environmental exposure.

BackgroundBalangero, 40 km northwest of Torino in the Piedmonte Region, was home to the largest and most active chrysotile mine in Europe operating from 1916 - 1990 and employed over 300 men at any one time. The chrysotile was thought to be pure. Despite this some claim it has been responsible for causing numerous mesotheliomas. This report refutes this claim on the grounds that it is not pure but potentially contaminated by tremolite asbestos. In addition there are numerous alternate sources of naturally occurring and commercially available amphibole asbestos in the region.MethodsGeological studies illustrate the presence of naturally occurring tremolite and various analyses have shown naturally occurring and commercially used amphibole its presence in animal and human tissue. The diagnostic criteria used to study pleural disease in the Balangero cohort were examined on a case by case basis. ResultsSeveral authors have searched available registries for post-mortem information and listed possible mesothelioma cases. Cross matching these searches has been attempted and the strength of their diagnoses examined. Conclusion.There is good evidence that crocidolite, amosite and tremolite are responsible for the alleged mesothelioma cases at Balangero. Myriad sources of naturally occurring and commercial amphibole asbestos exist in the region to account for the alleged cases. Regrettably, necessary information is incomplete and insufficient for the cohort which calls the diagnostic accuracy of the cases into question. The problem is further compounded by confusion surrounding job titles and raises the question if any of cases actually ever occurred in ‘miners’ per se.

Anthophyllite is an amphibole mineral formed through a prograde metamorphism of magnesium-rich ultramafic talcose rocks through increasing pressure and temperature and dehydration. The talc and anthophyllite are in phase equilibrium. Anthophyllite asbestos is therefore not a ‘contaminant’ of talc but a product derived from it. Fibrous talc, or so-called transitional fibers, are anthophyllite fibers undergoing retrograde degeneration. In its fibrous asbestiform state, anthophyllite differs in several fundamental ways from other commercially exploited forms of amphibole asbestos of which there are two broad families: monoclinic and orthorhombic. The more common forms of commercial amphibole asbestos such as crocidolite and amosite are monoclinic. The anthophyllites are orthorhombic. The differences between the two crystal systems are reflected at the level of the basic amphibole-structure in a greater overall fiber width dimensional profile and a significant reduction in microstructural strength. Strength reduction most probably arises at the cellular level and is particularly pronounced within the thinner population of fibers. Here microstructural differences, due in significant part to stacking defects in the basic amphibole structure, can account for these observations. The lack of an observed attendant mesothelioma risk following exposure to anthophyllite and transitional fibers in humans is a consequencel of these microstructural features that appear to differentiate them from the equidimensional monoclinic forms of amphibole asbestos such as South African crocidolite and amosite.

The largest anthopyllite deposits in the world are found in Finland and it is from here that most of the commercial anthophyllite derives. However, other large deposits exist in both North America and Japan. Commercial production has existed in both these countries although not on a scale which matches the Finnish mines. Small deposits are known from several other countries but, apart from minor exploitation in India no significant mining has taken place. The North American deposits are primarily in the Eastern US states, mostly Maryland, Georgia and North Carolina although there was also extensive exploration in Alabama. In Japan, the major mining site was at Matsubase on the southermost island of Kyushu. Although these mines and attendant commercial concerns operated for decades and under conditions of high dust exposure no mesothelioma clusters are known from the mining areas.

Lithium as an essential element for human life is still a subject of controversy. However, it is accepted that it does have profound neurological effects and is a valuable treatment for bipolar disease. Generally, it occurs in barely trace amounts in groundwater with few major exceptions. One of these is the Northern area of Chile where all potable water and many of the food stuffs contain high levels of lithium; between 100 and 10,000 times higher than most rivers in North America. Inevitably, the local population has been exposed to these levels in their drinking water for as long as the region has been populated. The present report details lithium levels in all the surface water sources of Northern Chile with comparison to that elsewhere. The implications for the local population are discussed and their situation compared to those exposed to other sources of lithium pollution.

Although people in all sectors of the Finnish anthophyllite industry, including their families, have been heavily exposed to anthophyllite there is no evidence for even a single proven case of attributable mesothelioma. A few cases have been claimed but the evidence either, that they were mesotheliomas or that amphibole exposure was solely to anthophyllite is, in every case examined, insufficient. Even among the population who lived in Karelia in Central Finland who were exposed domestically or enviromentally to anthophyllite released during agricultural and various domestic activities and during transport from the mines, Finnish epidemiology found no risk of mesothelioma. There is also an absence of mesotheliomas reported in the earlier Finnish literature. This anomaly compared to the effects of exposure to other amphiboles is strong support for the role of fiber width in mesothelioma production. Anthophyllite, though, is not without clinical effect. As screening techniques improved it was discovered that of every person over the age of 65 years, one third living in Karelia had bilateral pleural plaques. The area was henceforth called the Endemic Pleural Plaque (EPP) zone. Radiographic analysis of the residents living in the district of Kuusjarvi led to suggestions that the cases resulted from asbestos blown from the Paakila facility via fiber drift as far away as 30 km. Later studies showed that ‘fiber drift’ was very unlikely to be a factor in the radiological findings thus observed.

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BackgroundThe hypothesis that fibre width is a major determinant of mesothelioma induction has been examined by comparative studies of two crocidolites from different sources. Fine fibres fromCapesouthAfricaand the thicker fibre found and used similarly inBolivia. It is well established that ‘thin’ fibre crocidolite fromCapeSouth Africais extremely mesotheliomagenic. Bolivian crocidolite has a much wider width distribution and relatively little mesothelioma inducing potential. MethodsWe analysed the mesothelioma demography inBoliviawhere local crocidolite has been used for decades This was compared with the mesothelioma demography in theItalianCityof Casale Monteferrato whereCapecrocidolite was processed for many decades in the Eternit Asbestos Cement plant producing numerous cases of mesothelioma.We also conducted a limited downwind study from the fiberizing part of the historical operating plant where products containing Bolivian crocidolite were made for sale and use inCochabamba. ResultsThe demographic study confirmed the absence of a significant mesothelioma excess inBolivia.Despite the extremely high fibre concentrations measured in the plant, no significant fibre levels were detected 100 meters away. Conclusion These preliminary findings undermine claims such as those made at Casale that crocidolite fibre can drift up to 15 km and remain airborne in quantities sufficient to contribute significantly to mesothelioma induction. We propose the difference in thickness and the attendant reduction in the percentage ofStantonfibres provides an explanation for the difference in mesothelioma patterns found in each city.

Anthophyllite asbestos only occurs in a few parts of the world in sufficient quantities to be mined. The largest deposits of anthophyllite asbestos occur in Finland where it was mined for more than 75 years and very extensively used and distributed, anciently, for more than six millennia. Anthophyllite is one of the five minerals known collectively as amphibole asbestos. Studies of the effect of these five mineral fibre types when inhaled have shown that fibre width is an important determinant of mesothelioma induction. Only the “thinner” fibres or those with fiber diameter dimensional profiles predominantly less than 0.25 – 0.30 µm, are clearly mesotheliogenic. The “thicker” ones or those whose predominant widths are greater than these diameters do not appear to show an observable attendant risk of mesothelioma. Observations based on studies of at least, two “thick” forms of amphibole asbestos support these hypotheses. The one is Bolivian crocidolite; the other Finnish anthophyllite. The Finnish anthophyllite industry presents an important opportunity to study the robustness of the theory that fibre width is key to mesothelioma genesis as vast numbers of people in all sectors of the Finnish industry and their families have historically incurred massive fiber exposures sufficient to cause a gross excess of asbestosis. Nonetheless, in spite of these long term, high dose exposures clear evidence for a mesothelioma risk due to anthophyllite asbestos is still lacking.

Italian talc from the Pinerolo Mines in North West Italy is known for its extreme purity. Several historical investigations of these mines have demonstrated very small amounts of tremolite in the host rock that occasionally found their way into the mined ore. However, more than sixty years of epidemiological studies of the Pinerolo miners and millers have failed to demonstrate any attendant cancer risk and show that this trace tremolite contamination is of no biological significance.Claims made that the Pinerolo Italian cosmetic talc produced prior to 1975 were contaminated with asbestos, principally tremolite, have been difficult to refute given the lack of authentic historical samples of commercial products. We now describe the analytical findings of a recently discovered authentic historical sample.Sample analyses of this material showed only a few non-asbestiform tremolite fibres - a finding discussed in the light of the historical (pre-1975) studies of this talc deposit: no serpentine (chrysotile) or amphibole fibres were detected.The numerical concentration of tremolite fibres in the talc sample was 3.687 x 106 fibres/gram, corresponding to a mass concentration of 0.722 parts per million.

Crocidolite is a fibrous mineral with unusual crystallography in that the fiber width varies according to geographical origin. The fibers from the mining areas of Western Australia and the Cape Province, in South Africa are ‘thin’ compared to those from Bolivian and some other mines. Regardless, the mineral is a well known causative agent for mesothelioma. The literature contains many reports of the disease occurring as a consequence of so called environmental exposures due to what some believe to be ‘low’ dose, ambient exposure. However, closer examination of these exposure conditions generally reveals an unrecognized (or simply ignored) strong domestic (para-occupational) exposure component. Oftentimes, the importance of such domestic exposures is not considered since they too are thought to be too low to contribute to risk. We have, for the first time, applied state of the art measurement methods to evaluate domestic (shake out) conditions created by workers in a historical unregulated crocidolite-cement based operating plant in Bolivia. Our results show that exposures can reach levels more usually associated with historic occupational exposures. The reason for studying the exposures in such a plant is that epidemiological studies have shown that ‘thin’ crocidolite fibers are associated with a high mesothelioma risk while exposure to the ‘thick’ Bolivian fibers are associated with a much lessened mesothelioma risk.

Lithium, generally, occurs in barely trace amounts in ground water with few major exceptions. One of these is the northern area of Chile where all potable water and many of the food stuffs contain high levels of lithium. Surface water can contain between 100 and 10,000 times more than most rivers in North America. Inevitably, food, both animal and vegetable, contains higher lithium levels than found elsewhere. In consequence, the local population has been exposed to high levels of lithium in their food and drinking water for as long as the region has been populated. The present report details lithium levels in a variety of food stuffs from several locations in Northern Chile and compares these with those found elsewhere. The implications for the local population have been discussed in our earlier paper.

A premature infant with severe respiratory distress developed the clinical and radiologic signs of pneumoperitoneum. At operation, free intraperitoneal air without visceral perforation was found. This case is unique in that pneumothorax was never observed and that interstitial emphysema or ischemic gastrointestinal lesions were not present at autopsy. The patient, however, was on a positive pressure ventilator for some time because of hyaline membrane disease and early pulmonary oxygen toxicity. Reduced parenchymal compliance could predispose to alveolar rupture. Although there was no clinical or anatomic evidence to point to a source of the intraperitoneal air, an undetectable pulmonary rupture with prompt dissection into the peritoneal cavity is the most likely explanation for the pneumoperitoneum.

✓ A case is reported of a patient in whom an intracranial extracerebral melanoma developed in association with a life-long nevus of Ota. Melanotic pigmentation of the skull, periosteum, and meninges beneath the nevus was found at operation.

✓ The authors report a case of cerebellar pseudotumor caused by a Candida species without evidence of any underlying systemic disorder or extracranial disease. Total removal followed by treatment with amphotericin B resulted in a favorable outcome.