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PubMed1983

Atmospheric deposition of iron from mining activities in northern Ontario.

Samples of Sphagnum moss were collected at varying distances from two iron-mining and processing centres in northern Ontario, Canada--Atikokan and Sudbury--and analyzed for Fe. All samples were collected in ombrotrophic bogs which receive chemical inputs strictly from atmospheric deposition. Mosses from the Atikokan sites exhibited elevated concentrations of Fe up to 7352 mg kg-1 near the local sources, and declined exponentially with distance to lows of 1443 mg kg-1. Atikokan, a mining and ore-processing centre, caused elevated Fe levels up to 50 km distance from the town, while Sudbury exhibited a greater influence due to the tall stack there. At Sudbury, levels ranged from 2478 mg kg-1 near the town down to 382 mg kg-1 in remote sites. Results from these moss analyses were similar to those obtained from precipitation sampling of previous authors.

Environmental Pollutants↗
PubMed1990

Health problems in Galena, Kansas: a heavy metal mining Superfund site.

Health problems at a heavy metal mining Superfund site were surveyed using prevalence information from 1980-85. Current environmental exposures include lead and cadmium in drinking water, mine wastes, and surface soils. Age- and sex-specific illness rates in whites in an exposed town (Galena) were compared with similar rates in two control towns. Multivariate analyses of morbidity data examined statistically significant risk factors for relevant illness in the three towns. Mortality rates for 1980-85 for white residents of Galena and for the U.S. were compared using univariate analysis. Among residents of the three towns who had lived there at least 5 years prior to 1980, there was either a statistically significant or borderline excess reported prevalence in Galena of chronic kidney disease (females aged greater than or equal to 65), heart disease (females aged greater than or equal to 45), skin cancer (males aged 45-64), and anemia (females aged 45-64). Multivariate analyses revealed statistically significant associations of stroke, chronic kidney disease, hypertension, heart disease, skin cancer, and anemia with variables related to Galena exposure. Personal physicians were contacted to confirm the information provided by the subjects; validity was good for all reported illnesses except chronic kidney disease. A statistically significant excess of deaths from hypertensive disease (females aged greater than or equal to 65), ischemic heart disease (males and females aged greater than or equal to 65), and stroke (females aged greater than or equal to 65) was found in residents of Galena City. This study confirms that environmental agents in Galena are associated with, and may have contributed to, the causation of several chronic diseases in residents of this community. Further studies are recommended.

Adult↗
PubMed1995

Mercury in environmental and biological samples from a gold mining area in the Amazon region of Brazil.

A massive increase in gold mining in the Amazon region of Brazil has led to an enormous discharge of metallic mercury into the aquatic ecosystem. To investigate the dispersion, total and inorganic mercury concentrations were measured in water, fish and animal tissues, and in blood, urine and hair from members of the local populations. Mercury concentrations in river water, sediments and fish were high compared with those of non-contaminated areas. Cattle and pigs kept in the area and with access to the contaminated rivers had concentrations of mercury of 0.1-1.28 micrograms/g and 11.7-15.7 micrograms/l in hair and blood, respectively. These results are approximately twice those measured in specimens from control animals. Mean mercury concentrations in blood, urine and hair of residents were increased at 11.4 micrograms/l, 22.8 micrograms/l and 4.3 micrograms/g, respectively, and the urine mercury of workers from the gold mining sites were up to 155 micrograms/l. The results demonstrate widespread contamination of the environment by mercury with transfer of the metal to fish and animals used for food, and into the inhabitants of the region. Further investigations for possible adverse health effects need to be undertaken.

Animals↗
PubMed1985

Chromosomal abnormalities in soft coal open-cast mining workers.

Chromosome aberration tests on cultured peripheral blood lymphocytes were carried out in two groups of open-cast mining workers engaged in stripping operations (Group I) and digging operations (Group II), in a group of coal cleaning plant workers used as a positive control, and in a group of nonexposed subjects serving as matching controls. Peripheral blood samples in group I and group II miners were collected in March and June of 1984, the antimutagenic potential of long-term prophylactic vitamin administrations (1 g of ascorbic acid given daily for a period of 3 months and 100 mg of vitamin A a day for two 5-day cycles) initiated after the first blood sampling was tested in group II miners. The frequency of aberrant cells (% AB.C.) found in the cultured lymphocytes of group I miners was increased at both times of measurement (2.41% AB.C. and 2.29% AB.C.), in group II miners given the vitamin prophylaxis it dropped significantly (P greater than 0.01) from the initial 3.16% AB.C. in March to 1.77% AB.C. in June, and in the group of coal cleaning plant workers (1.30% AB.C.) it was more or less equal to that of matching controls (1.21% AB.C.). Implicitly, coal dust alone can hardly be made responsible for the rise in % AB.C. It appears that the increase in frequency of chromosome aberrations observed in soft coal open-cast mining workers rather reflects an increased risk of genetic injury due to exposure to ever-present fumes and fire hazards that may give rise to the mutagenic chemicals belonging to a class of polycyclic aromatic hydrocarbons. The antimutagenic effect of ascorbic acid prophylaxis was characterized by a significant drop in % AB.C. and a speed-up of the lymphocyte cell cycle expressed as the proliferating rate index (PRI) whose value rose from the original 1.41 to 1.69, thus reaching the PRI value of matching controls (1.63).

Ascorbic Acid↗
PubMed1993

Disease and mortality among gold miners of Ghana: colonial government and mining company attitudes and policies, 1900-1938.

This article traces the causes of high mortality rates among African gold miners in the former British colonial territories of the Gold Coast and Ashanti, 1900-1938. No previous studies exist for the early decades owing to the neglect by both mining companies and government officials to keep adequate statistics on African miner death rates, a flaw which reinforced the lackadaisical response of the government to problems of prevention and treatment. A milestone report issued in 1924, demonstrating that sanitary precautions, housing conditions and medical treatment for most African miners were wretched, forced the colonial state to gather regular data on Africans and make long overdue improvements, so that mortality rates for underground miners slowly declined by the time of the Second World War. But the published statistics concealed from view the far greater incidence of general deaths from pulmonary and respiratory tract disease among short-term migrant labourers, who lived in the mining towns, but returned to die in their home villages.

Accidents, Occupational↗
PubMed1994

Results from a community intervention project in the Nicaraguan mining community El Limon. An overview.

The first steps of a community involvement health project using the principles of community diagnosis and popular participation were carried out in a small Nicaraguan mining village during the second half of the 1980s. Using existing archives and obtaining new information aided by local organizations, priorities could be established for health and safety surveillance within the mining company, as well as for further investigations concerning what seemed to be dominant health problems in the community: serious accidents among the economically active population and diarrhoea and respiratory tract infections among children, as well as infections, and other health indicators of malnutrition. Workers also presented chronic simple bronchitis, ventilatory obstructive disturbance and hearing loss that were strongly associated with working conditions. These results helped to direct health priorities and educational activities at the local level with both the general and working population. The wide experience gained from this study has encouraged us to strengthen the link between research and action and in performing studies in close cooperation with local organizations.

Adult↗
PubMed2004

Vibration in operating heavy haul trucks in overburden mining.

The objective of this study was to determine if the vibration in sagittal (x), coronal (y) and vertical (z) axes of the seat pan of the heavy haul trucks used in overburden mining, and the vibration experienced by the drivers at the third lumbar and seventh cervical vertebral levels in operating these trucks exceeded the ISO standards, thereby posing threat to safety. A new and an old truck of two different makes and different carrying capacities (200 and 300 series) were instrumented with a triaxial accelerometer on the seat pan. Fourteen drivers (8 male and 6 female) were instrumented with a triaxial accelerometer at C7 and L3 spinous processes. The vibration at the seat pan, C7, and L3 levels were recorded using an onboard computer with PCMCIA card and, compared against the ISO standards. The vertical vibration of the seat pan in the entire sample ranged from a low of .37 m/s2 to a high of 11.73 m/s2. The vibration at the lumbar level in the sample ranged between .34 and 2.72 m/s2. The values for cervical level vertical vibration in the sample ranged between .2 and 2.22 m/s2. The gender of the driver, truck make, and it's carrying capacity did not have a significant effect on the vibration. However, the body weight of the driver, the segment of the truck and the site of measurement revealed significant differences in vibration (p < 0.001). Out of a total 36 combinations (4 trucks x 9 recording locations) the seat pan vertical vibration exceeded the ISO standards 8 times for males and 9 times for females. The lumbar vertebral vertical vibration in males exceeded ISO standards 12 times and in females 11 times. The cervical vertebral vertical vibration exceeded ISO standards once in females only. However, in sagittal and coronal planes the whole body vibration exceeded the ISO standards many times. Heavy haul trucks (240 and 320 ton capacity) frequently generated vibrations in excess of ISO standards in overburden mining operation representing a health hazard.

Adult↗
PubMed2005

The long-term environmental behaviour of strontium and barium released from former mine workings in the granites of the Sunart region of Scotland, UK.

The concentrations of strontium and barium have been measured in water, sediment and the shells of mussels (Mytilus edulis) from a river system in the Sunart region of Scotland, UK. The aim was to establish the fate and mobility of these elements, which are slowly being released from old mine workings on the Strontian granites. Enhanced strontium (1500-2000 microg l(-1) and 250-290 microg l(-1)) and barium concentrations (316 microg l(-1) and 83 microg l(-1)) were found in the waters originating from the two mine drains studied. Both element were also found at significant levels in the river sediments taken from the vicinity of each drainage site (Sr: 225 microg g(-1) and 120-125 microg g(-1); Ba: 1380 microg g(-1) and 126-170 microg g(-1)). The data suggests that the sediments are acting as a reservoir for these group II cations from where they become distributed throughout the river system. Strontium is found to be incorporated into the shells (3.16-3.46 microg g(-1)) and pearls (3.57 microg g(-1)) of the blue mussel, located at the estuarine margin some 10 km downstream, at values close to the maximum expected (3.3% by weight of the calcium content). The study presents a view of the fate of barium and strontium in a river system over a prolonged period of time. As such it provides valuable information for studies that seek to model the impact of the accidental release of barium and strontium (including the important radionuclide 90Sr) into the environment.

Animals↗
PubMed2005

Effects of heavy metals on sea urchin embryo development. Part 2. Interactive toxic effects of heavy metals in synthetic mine effluents.

Interactive toxic effects between heavy metals were investigated using a sea urchin (Anthocidaris crassispina) bioassay. An effluent from an abandoned mine showed significant inhibitory effects on embryo development as well as producing specific malformations. The effects on the embryos were reproduced by synthetic polluted seawater consisting of eight metals (manganese, lead, cadmium, nickel, zinc, chromium, iron, and copper) at the concentrations detected in the mine effluent. This indicated that the heavy metals were responsible for the effects observed. Five heavy metals were ranked in decreasing order of toxicity as follows: Cu>Zn>Pb>Fe>Mn. Among these, zinc and manganese could cause malformation of the embryos. From bioassay results using 27 combinations of heavy metals, 16 combinations including zinc could produce specific malformations, such as radialized, exo-gastrulal, and spaceship Apollo-like gastrulal embryos. Zinc was one of the elements responsible for causing malformations and its effects were intensified by the presence of the other metals, such as manganese, lead, iron, and copper.

Animals↗
PubMed2005

Lead, cadmium and arsenic bioavailability in the abandoned mine site of Cabezo Rajao (Murcia, SE Spain).

An in vitro method that simulated the physiological conditions of the digestive process was applied to samples taken from an old mining site, providing information on the levels of metals (Cd, Pb and As) that can be ingested and assimilated by humans. Samples were first characterized by determining pH, texture, mineralogical composition and total metal contents. The mean pH value was 5.4, ranging from 3.1 to 8.4. The mean total metal content for Pb was 2,632+/-59 mg kg(-1), 65+/-1.5 mg kg(-1) for Cd and 279.9+/-9.9 mg kg(-1) for As. Cadmium was the most bioavailable metal both in the stomach and intestinal phases (mean value of 47% and 27.8%, respectively), followed by lead (25.3% and 11.5%) and arsenic (4.9% and 0.5%). A Pearson correlation matrix suggested that pH and mineralogical composition were important factors controlling metal bioavailability from materials in abandoned mining sites.

Arsenic↗
PubMed2006

Diel cycles of arsenic speciation due to photooxidation in acid mine drainage from the Iberian Pyrite Belt (Sw Spain).

Twenty four hours diel cycles of arsenic speciation in Acid Mine Drainage (AMD) due to photooxidation have been reported for the first time. AMD samples were taken during 48 h (31st March and 1st April, 2005) at 6 h intervals from the effluent of a massive abandoned polymetallic sulphide mine of the Iberian Pyrite Belt (Sw Spain). Samples were preserved in situ using cationic exchange prior to analysis by coupled high performance liquid chromatography, hydride generation and atomic fluorescence spectrometry (HPLC-HG-AFS) for arsenic speciation. The results indicated the presence of inorganic arsenic species with daily means of 262mugl(-1) for As(V) and 107 microg l(-1) for As(III). No marked diel trend was observed for As(V). However, a marked diel trend was observed for As(III) in the two studied days, with maximum concentrations during nighttime (141-143 microg l(-1)) and minimum concentrations at daytime (72-77 microg l(-1)). This difference in concentration during daytime and nighttime is ca. 100%. A similar diel cycle was observed for iron. An explanation for the arsenic diel cycles observed is the light induced photooxidation of As(III) and the elimination of As(V) due to its adsorption onto Fe precipitates during the daytime. Furthermore, the diel changes in arsenic speciation emphasize the importance of designing suitable sampling strategies in AMD systems.

Arsenic↗
PubMed2005

The dispersion of heavy metals in the vicinity of Britannia Mine, British Columbia, Canada.

Britannia Mine in British Columbia, Canada, is a major source of copper and other heavy metal pollutants, which enter the sea at Howe Sound. This investigation aims to determine whether there is sufficient Cd, Cu, Pb, and Zn, in the terrestrial environment surrounding the mine to suggest that dispersion and subsequent bioaccumulation has occurred in the past and continues. Samples of spoil, vegetation, and water were collected in January 2003 from areas at sea level and up to an altitude of 790 m. The samples of soil and vegetation were digested with aqua regia. The subsequent extracts and water samples were analyzed using flame atomic absorption spectrophotometry. The target metal concentrations were found to be much higher on the hillside spoil tips than on the seashore where the ore concentrators had formerly been located. The dispersion of heavy metals into the surrounding biosphere is discussed and further investigations into dispersion and partitioning within organisms including humans are suggested.

British Columbia↗
PubMed2006

Effect of heavy metals on substrate utilization pattern, biomass, and activity of microbial communities in a reclaimed mining wasteland of red soil area.

The microbial biomass, basal respiration, and substrate utilization pattern in a copper mining wasteland of red soil area, southern China, were investigated, and indicated that soil microflora were obviously affected by heavy metals. Microbial biomass and basal respiration were negatively affected by comparatively high heavy metal levels. Two important microbial ecophysiological parameters, namely, the microbial biomass C (C(mic))/microbial biomass N (N(mic)) ratio and the metabolic quotient (qCO(2)) were significantly correlated to heavy metal stress. There was a significant decrease in the C(mic)/N(mic) ratio and an increase in the metabolic quotient with increasing metal concentration. Multivariate analysis of Biolog data for sole carbon source utilization pattern demonstrated that heavy metal pollution had a significant impact on microbial community structure and functional diversity. All the results showed that soil microbiological parameters could have great potential as sensitive, effective, and liable indicators of the stresses or perturbations in soils of mining ecosystems.

Biodegradation, Environmental↗
PubMed2006

Acid mine drainage pollution in the Tinto and Odiel rivers (Iberian Pyrite Belt, SW Spain) and bioavailability of the transported metals to the Huelva Estuary.

The Tinto and Odiel rivers are seriously affected by acid mine drainage (AMD) from the long-term mining activities in Iberian Pyrite Belt (IPB). As a consequence, the Huelva estuary is heavily contaminated by metals and metalloids. This study presents an estimation of the seasonal variation, and the dissolved contaminant load transported by both rivers from February 2002 to September 2004. Besides, toxicity and bioaccumulation tests with the sediments of the estuary have been conducted in order to measure the mobility of the toxic metals. Results show that the Tinto and Odiel rivers transport enormous quantities of dissolved metals to the estuary: 7900 t yr(-1) of Iron (Fe), 5800 t yr(-1) Aluminium (Al), 3500 t yr(-1) Zinc (Zn), 1700 t yr(-1) Copper (Cu), 1600 t yr(-1) Manganese (Mn) and minor quantities of other metals and metalloids. These values represent 37% of the global gross flux of dissolved Zn transported by rivers in to the ocean, and 15% of the global gross flux of dissolved Cu. These metals and metalloids usually sink in the estuarine sediments due to pH and salinity changes. The increase of salinity in the estuary favours the adsorption and trapping of metals. For this reason, the mobility and bioavailability of metals such as Zn, Cd and Cu is higher in sediments located in the area of fresh water influence that in sediments located in the marine influenced area of the estuary, showing a higher percentage of fractionation and bioaccumulation of these metals in the station influenced by the fresh water environment.

Acids↗
PubMed2004

Sediment quality in littoral regions of the Gulf of Cádiz: a triad approach to address the influence of mining activities.

To evaluate sediment quality in different areas in the Gulf of Cádiz affected by mining activities, an integrative approach to assessment was used: the Sediment Quality Triad (SQT). Sediment samples were collected at six stations and subjected to replicated sediment acute and chronic toxicity tests, and comprehensive sediment chemistry analyses. Organisms collected synoptically at the same stations were analyzed for histopathological lesions and chemical concentrations in their tissues to determine 'in situ' alteration and bioavailability, in place of benthic community structure. The results obtained for each component were linked to the SQT using different methodologies of interpretation and expression of the integrated approach: (a) multivariate analysis, (b) significant statistical differences compared to the reference stations, (c) ANOVA-based pie charts, and (d) classical methods using triangles and the SQT index of pollution. SQT results indicated that the highest pollution was mainly associated with metals from mining activities and polyaromatic hydrocarbons in the Ría of Huelva. The use of histopathological measures and bioaccumulation of metals, improved the characterization of 'gray areas' of pollution and in the determination of the bioavailability of metals.

Biological Availability↗
PubMed2005

Depauperate macroinvertebrates in a mine affected stream: clean water may be the key to recovery.

Acid mine drainage (AMD) is frequently linked with changes in macroinvertebrate assemblages, but the relative contribution of water and sediment to toxicity is equivocal. We have shown that the macroinvertebrate fauna of Neubecks Ck, a mine impacted stream in New South Wales, Australia, was much poorer than in two reference streams. Multivariate RELATE analyses indicated that the patterns in the biological data were more strongly correlated with the concentrations of common metals in the surface water than the pore water of these streams. From this we hypothesised that the water was more toxic to the biota than the sediment and we tested this hypothesis with a sediment transplant experiment. Sediment from Neubecks Ck that was placed in reference streams retained high concentrations of metals throughout the experiment, yet supported a macroinvertebrate assemblage similar to that in the reference streams. Sediment from the reference streams that was placed in Neubecks Ck supported few, if any, animals. This indicates that water in Neubecks Ck is toxic to biota, but that sediment is able to support aquatic biota in clean water. Therefore, remediation should focus on improving water quality rather than sediment quality.

Animals↗
PubMed2005

Assessment of the ecological potential of mine-water treatment wetlands using a baseline survey of macroinvertebrate communities.

A baseline survey of macroinvertebrate populations in two mine-water treatment wetlands, one treating a net acidic spoil heap discharge and one a net alkaline ferruginous pumped mine water, was undertaken to assess the potential of these systems to provide habitats for faunal communities. Both wetlands were found to be impoverished in comparison to natural wetlands but did sustain a macroinvertebrate community that could support higher organisms. Wetland size and water quality in terms of pH, conductivity and metal concentrations were found to be important factors in determining the quality of the populations supported. Direct toxicity to organisms was unlikely to be the main cause of lower diversity, but the smothering of organisms via the precipitation of iron hydroxides particularly in the early parts of the treatment systems affected macroinvertebrate communities. The presence of areas of open water within the planted systems was found to be important for providing habitats for macroinvertebrates and this should be both a future design and maintenance consideration for environmental managers.

Animals↗
PubMed2005

Tissues and hair residues and histopathology in wild rats (Rattus rattus L.) and Algerian mice (Mus spretus Lataste) from an abandoned mine area (Southeast Portugal).

Data gathered in this study suggested the exposure of rats and Algerian mice, living in an abandoned mining area, to a mixture of heavy metals. Although similar histopathological features were recorded in the liver and spleen of both species, the Algerian mouse has proved to be the strongest bioaccumulator species. Hair was considered to be a good biological material to monitor environmental contamination of Cr in rats. Significant positive associations were found between the levels of this element in hair/kidney (r=0.826, n=9, p<0.01) and hair/liver (r=0.697, n=9, p=0.037). Although no association was found between the levels of As recorded in the hair and in the organs, the levels of this element recorded in the hair, of both species, were significantly higher in animals captured in the mining area, which met the data from the organs analysed. Nevertheless, more studies will be needed to reduce uncertainty about cause-effect relationships.

Animals↗