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PubMed2005

Generation of polluted waters from mining wastes in a uranium deposit.

Dump consisting of 9500 tons of rich-in-pyrite mining wastes located in the uranium deposit Curilo, Western Bulgaria, was, after rainfall, an intensive source of acid drainage waters. These waters had a pH in the range of about 1.7-4.5 and contained radionuclides (uranium, radium), heavy metals (copper, zinc, cadmium, lead, nickel, cobalt, iron, and manganese), arsenic and sulphates in concentrations usually much higher than the relevant permissible levels for waters intended for use in the agriculture and/or industry. The generation of these polluted waters was studied under real field conditions for a period of about seven years during different climatic seasons. It was found that the dump was inhabited by a diverse microflora in which some acidophilic chemolithotrophic bacteria were the prevalent microorganisms. The solubilization of the above-mentioned pollutants from the dump material was connected mainly with the oxidation of pyrite and other sulphide minerals by these bacteria. Their activity depended on some essential environmental factors such as temperature, pH, and water, oxygen and nutrient contents in the dump.

Acid Rain↗
PubMed2001

Mine water pollution in Scotland: nature, extent and preventative strategies.

Scotland was one of the world's first industrialised countries, and has therefore also been one of the first countries to experience wholesale post-industrial dereliction. Water pollution arising from abandoned mines, particularly abandoned coal mines, is second only to sewage as a source of freshwater pollution nation-wide, and in many coalfield catchments it is the pre-eminent source. Most of the pollution is due to net-alkaline ferruginous waters emerging from deep mines. Scrutiny of records from 80 deep mine discharges reveals that iron concentrations in these waters are only likely to exceed 20 mg/l, and the pH to be below 6.5, where the discharge emerges within 0.5 km of the outcrop of the shallowest mined seam. The bulk of mature near-outcrop mine water discharges in Scotland have < 50 mg/l total Fe, and concentrations > 100 mg/l are only likely where a marine bed lies within 25 m of the worked seam. Where the nearest marine bed is more than 80 m above or below the seam, then the total iron will be less than 4 mg/l, and in most cases less than 1 mg/l. Net-acidic mine waters are far more rare than net-alkaline waters in Scotland, and are most commonly associated with unreclaimed spoil heaps (bings). Both net-alkaline and net-acidic discharges have detrimental effects on the hydrochemistry and biological integrity of receiving waters. Scotland has recently pioneered the use of pre-emptive pump-and-treat solutions to prevent mine water pollution, and has also experienced the successful introduction of passive treatment technology for both abandoned and active workings.

Conservation of Natural Resources↗
PubMed2005

Effects of cattle manure on erosion rates and runoff water pollution by faecal coliforms.

The large quantities of slurry and manure that are produced annually in many areas in which cattle are raised could be an important source of organic matter and nutrients for agriculture. However, the benefits of waste recycling may be partially offset by the risk of water pollution associated with runoff from the fields to which slurry or manure has been applied. In this paper, the effects of cattle manure application on soil erosion rates and runoff and on surface water pollution by faecal coliforms are analysed. Rainfall simulations at a rate of 70 mm h(-1) were conducted in a sandy loam soil packed into soil flumes (2.5m long x 1m wide) at a bulk density of 1400 kg m(-3), with and without cattle slurry manure applied on the surface. For each simulation, sediment and runoff rates were analysed and in those simulations with applied slurry, presumptive faecal coliform (PFC) concentrations in the runoff were evaluated. The application of slurry on the soil surface appeared to have a protective effect on the soils, reducing soil detachment by up to 70% but increasing runoff volume by up to 30%. This practice implies an important source of pollution for surface waters especially if rainfall takes place within a short period after application. The concentrations of micro-organisms (presumptive faecal coliforms (PFCs)) found in water runoff ranged from 1.9 x 10(4) to 1.1 x 10(6) PFC 100mL(-1), depending on the initial concentration in the slurry, and they were particularly high during the first phases of the rainfall event. The result indicates a strong relationship between the faecal coliforms transported by runoff and the organic matter in the sediment.

Animals↗
PubMed1990

Health effects of beach water pollution in Hong Kong.

Prospective epidemiological studies of beach water pollution were conducted in Hong Kong in the summers of 1986 and 1987. For the main study in 1987, a total of 18741 usable responses were obtained from beachgoers on nine beaches at weekends. The study indicated the overall perceived symptom rates for gastrointestinal, ear, eye, skin, respiratory, fever and total illness were significantly higher for swimmers than non-swimmers; and the swimming-associated symptom rates for gastrointestinal, skin, respiratory and total illness were higher at 'barely acceptable' beaches than at 'relatively unpolluted' ones. Escherichia coli was found to be the best indicator of the health effects associated with swimming in the beaches of Hong Kong. It showed the highest correlation with combined swimming-associated gastroenteritis and skin symptom rates when compared with other microbial indicators. A linear relationship between E. coli and the combined symptom rates was established. Staphylococci were correlated with ear, respiratory and total illness, but could not be used for predicting swimming-associated health risks. They should be used to complement E. coli. The setting of health-related bathing-water quality standards based on such a study is discussed.

Adolescent↗
PubMed2006

Outdoor fecal deposition by free-roaming cats and attitudes of cat owners and nonowners toward stray pets, wildlife, and water pollution.

OBJECTIVE: To estimate cat population size, management, and outside fecal deposition and evaluate attitudes of cat owners and nonowners to stray animal control, water pollution, and wildlife protection. DESIGN: Cross-sectional survey. SAMPLE POPULATION: 294 adult residents of Cayucos, Los Osos, and Morro Bay, Calif. PROCEDURES: Telephone survey. RESULTS: The region's cat population was estimated at 7,284 owned and 2,046 feral cats, and 38% of surveyed households owned a mean of 1.9 cats/household. Forty-four percent of cats defecated outside >75% of the time. Annual fecal deposition (wet weight) by owned cats in the 3 communities was estimated to be 77.6 tonnes (76.4 tons). Cat owners were more likely to oppose cat licensing and impounding stray cats and support trap-neuter-return for stray cats and less likely to be concerned about water pollution, than were noncat owners. CONCLUSIONS AND CLINICAL RELEVANCE: Feral cats represented a sizeable proportion (22%) of the free roaming cats in this area and could be contributing 30.0 tonnes (29.5 tons) of feces to the environment per year. However, feral cats are not the principal source of fecal loading because owned cats defecating outdoors contribute an estimated 77.6 tonnes (76.4 tons) or 72% of the annual outdoor fecal deposition.

Animal Husbandry↗
PubMed2003

Adverse effects of (surface water pollutants) Cd, Cr and Pb on the embryogenesis of the mallard.

The effects of chromium, lead and cadmium were studied on the embryogenesis, hatching success and viability of the mallard. Eggs were exposed to relatively low environmental concentrations that are characteristic to the level in polluted Hungarian surface waters. Eggs were treated by injection or immersion--prior to incubation. In study I, effects on early embryogenesis (first 10 days of incubation) were examined. Eggs were opened daily, mortality was determined and permanent slides of the embryos were made to help further external examinations. Each metal proved to be toxic to the developing mallard embryo, causing an increase in mortality and developmental anomalies. Chromium was the most teratogenic of the three heavy metals increasing the rate of malformations by 30% (P<0.001) after immersion, and 17% (P<0.01) after injection of the eggs. Cadmium proved to cause the highest rate of mortality. Embryonic death was increased by 27% (P<0.01) and 40% (P<0.001) after Cd immersion and injection, respectively. In study II, effects on hatching and viability of the ducklings were studied. The eggs were hatched, hatching and mortality rates were established, the liver of animals was histopathologically examined. However each heavy metal decreased hatching success, cadmium was found the most toxic compound, causing a 21% (P<0.01) and 47% (P<0.001) reduction in hatching success after immersion and injection, respectively. The liver of hatched ducklings showed significant lesions, dystrophy in the form of hepatic necrosis was detected in each treated animal. Each heavy metal (Cr, Pb, Cd) proved to have adverse effects on the embryonic development, hatching and viability of the mallard.

Analysis of Variance↗
PubMedDate not supplied

Water pollution and diseases in fish (an epizootiologic survey).

Three watersheds, varying from highly polluted or moderately polluted to essentially pollution-free, were surveyed to determine the frequency of fish disease. Over a five year period, it was found that a relationship existed between the level of pollution and frequency of disease. The occurrence rates of microbial and oncogenic diseases increased similarly in relation to increases in pollution in the waters. Since the water systems studied provide recreational opportunities for man, it is suggested that catching and subsequent ingesting of diseased fish from these waters present a health hazard.

Animals↗
PubMed2003

[Farm compost polluted water may induce pharyngo-esophageal, gastric and liver carcinoma in the chicken].

OBJECTIVE: To study farm compost polluted water that may induce pharyngo-esophageal, gastric and liver carcinoma in chickens. METHODS: 280 chickens were randomized into 4 groups: experiment group 100 chickens fed with compost water + NaNO(2) by stomach tube. The other 180 were evenly randomized into 3 control groups (60 each), fed with compost water, NaNO(2) and tap water in the same way. The farm compost was prepared with corn stalks, rice straws, excreta of men and livestock. The compost water, after being nitrosified and acidified, was fed through stomach tube 5 - 7.5 ml/session, twice a week. Besides, a solution consisting of the respective formula of each group added with 3 - 4 L water with pH adjusted to 3 - 4 by 1N HCL was given ad lib to all chickens in each group for 26.5 months. RESULTS: In the experiment group, there were pharyngo-esophageal carcinoma 16 (16.3%), gastric adenocarcinoma 5 (10.4%) and liver carcinoma 3 (6.3%), in contrast to none in the 3 control groups, showing significant differences (P < 0.01, P < 0.01, P < 0.05). CONCLUSION: Successful simulation of the layout of esophageal carcinoma high morbidity area and the mimic of chicken gastric fluid strongly support our compost etiological hypothesis that the nitrosified and acidified compost water are carcinogenic, very well causing esophageal, gastric and liver carcinoma.

Adenocarcinoma↗
PubMedDate not supplied

Gas chromatographic/mass spectrometric confirmation of identity of coprostanol in Mercenaria mercenaria (Bivalvia) taken from sewage-polluted water.

Coprostanol is a major fecal sterol in humans and may, therefore, be a good indicator of sewage-polluted waters. Some types of edible seafood, such as clams, that live in these waters may be contaminated with coprostanol. Coprostanol from clam tissue extracts had been previously quantitated by gas chromatography (GC). In the present work, capillary column GC was used to separate coprostanol, and electron ionization mass spectrometry was used to confirm its identity. Confirmation of identity of coprostanol at the 75 ng level was obtained by comparing the spectrum of the authentic standard with spectra of the clam tissue extract obtained under the same instrumental conditions. Various other compounds can be eliminated as potential interferences by virtue of either their different GC retention times or their spectra.

Animals↗