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At least 559 records · Page 31Linked to original sources
PubMed1996

Trace elements in drinking water coolers collected from primary schools, Riyadh, Saudi Arabia.

A simple method for the spectrochemical analysis of water samples by inductively coupled plasma spectrometry is described. Samples from drinking water coolers in 32 schools in Riyadh were collected at a specific time during a typical school day and analyzed for aluminum (Al), beryllium (Be), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), silicon (Si), strontium (Sr), vanadium (V), and zinc (Zn) to ascertain the water quality. The analysis of drinking water showed high concentrations of metals and in some cases exceeded the guideline limits recommended by EEC and WHO.

Maximum Allowable Concentration↗
PubMed1978

Plutonium in drinking water: effects of chlorination on its maximum permissible concentration.

Soluble plutonium is oxidized to the Pi(VI) oxidation state by chlorine during water treatment. Under certain conditions Pi(VI) is readily absorbed from the gastrointestinal tract. It appears that due consideration has not been given to the effect that the presence of plutonium in this oxidation state may have on the maximum permissible concentration of plutonium in drinking water.

Animals↗
PubMed1990

[Suspended dust from artificial mineral fibers at the work site].

Products fabricated of man-made fibres, which are produced or processed in relatively large amounts in Austria, usually contain glass or rock wool. Regulations laid down limits for the exposure at the workplace to glass/rock wool dust. For this purpose, a gravimetric concentration threshold has been established for the assessment period "working year". A measuring procedure matched to the established threshold is employed to measure the concentration of airborne dust at the workplace.

Air Pollutants, Occupational↗
PubMed1989

[Lead level of the hair in persons occupationally exposed to it in selected work places].

The concentration of lead was determined in the hair of 69 occupationally exposed and 55 non-exposed subjects. The mean lead content in the three selected occupationally exposed groups was 17.48, 29.03 and 25.74 micrograms/respectively, significant differences being found between some of them. The mean lead content in the hair of unexposed population was 4.20 micrograms/g. Statistical analysis of the results demonstrated a highly significant difference in mean lead levels between exposed and non-exposed groups. The subjects occupationally exposed to lead and its compounds exhibited no significant correlation between lead concentrations in hair and delta-aminolevulinic acid concentrations in urine.

Adolescent↗
PubMed1987

[Smell threshold levels of substances as a criterion for evaluating the maximum permissible exposure levels].

Compared in the paper are the threshold limit values (TLV) and odour threshold concentrations (OTC) of 85 substances. As so far the generally accepted methods of odour nuisance measurements have been missing; the TLV/OTC ratio was adopted as a criterion of possible appearance of odour discomfort. The substances were divided into groups according to their feasibility of odorous nuisance. It was demonstrated that the odour discomfort might appear even with concentrations below TLVs. This particularly refers to styrene, naphthalene, CS2, pyridine and H2S.

Air Pollutants, Occupational↗
PubMed1985

[Evaluation of exposure of workers to asbestos dust in asbestos-processing plants].

Working environments have been tested in plants producing asbestos products, asbestos-cement products, textile asbestos products, asbestos-caoutchouc plates, asbestos boards and asbestos frictional materials for automotive industry, Measurements of total dust concentrations and concentrations of asbestos fibres 5 micron long supported workers' exposure investigations. Basing on literature data on the working environment at the Mining Metallurgical Plant in Szklary, the health risk for workers producing nickel from ores containing asbestos mixtures has been analysed. The asbestos-exposure in asbestos-processing plants has been found to be still considerable despite modernization of the plants. Particularly dangerous to health have been regarded the conditions at asbestos spinning-mills and the Mining-Metallurgical Plant at Szklary, where even average asbestos concentrations considerably exceed the threshold limit values.

Air Pollutants, Occupational↗
PubMed1994

[Value of nitrates and nitrites in selected vegetables and potatoes sold in the marketplace of Białystok in the years 1991-1992].

Nitrate and nitrite contents were determined in selected vegetables and potatoes from the market in Białystok and from ecology cultivation in the years 1991-1992. The modified Griess method was used for determination of nitrate. The results showed that the nitrate contents in red beets, cabbages, parsley, carrots, celery and potatoes, were higher than the suggested limit in Poland. In the group of vegetables from special cultivation plots, the nitrate contents also exceeded the maximal permissible level. Low nitrite concentrations were found in the studied vegetables.

Environmental Monitoring↗
PubMed1998

[Drinking water supply with reference to geogenic arsenic contamination].

Geogenic Arsenic in Drinking Water. Drinking water production of surface spring water in southern Lower Saxony (Niedersachsen, Germany) was reduced because of microbiological contaminations and unreliably variable water reserves. Surface spring water in general has a low arsenic content. As a consequence ground water has been increasingly used for drinking water. Thus, high geogenic concentrations of arsenic in the central "Buntsandstein" in southern Lower Saxony caused high arsenic contents in the groundwater. Under the regulation of the German Drinking Water Ordinance (1986) the limit for total arsenic (40 micrograms/l) was exceeded in 2% of 150 fountains, wells and sources in southern Lower Saxony. Because of the well-known cancerogenic potential of arsenic the limit for total arsenic in drinking water was reduced from 40 micrograms/l to 10 micrograms/l suspending the new standard value until January 1996. This regulation based on new calculations revealing a skin cancer risk of roughly 6:10,000 and a mortality risk of roughly 1:10(6) in respect of lifetime in case of arsenic concentrations of 10 micrograms As/l drinking water. After that limit change 40% of 150 wells and sources in southern Lower Saxony exceeded the arsenic limit of 10 micrograms/l drinking water. As a matter of fact, it became necessary for a large number of water supply works to eliminate arsenic from the drinking water by technical means or to dilute drinking water with high concentrations of arsenic.

Arsenic↗
PubMed2004

Smoke in the operating theater: an unregarded source of danger.

Monopolar electrocautery devices are being used in operating theaters worldwide and have become a "sine qua non" in modern surgery. Despite being widespread, the use of electrocautery is not harmless, because by burning the tissue with rather low temperatures as compared with usual combustion, toxic gases evolve and particles are dispersed and are inhaled by the staff in the operating theater. Samples of this smoke, which evolves particularly densely during reduction mammaplasty, were analyzed using a carbon dioxide laser photoacoustic spectrometer. Eleven gas components could be identified and quantified. In particular, the established concentration of 2-fur-ancarboxaldehyde (furfural) measured at 2 cm from the point of origin was outstandingly high, being 12 times higher than the occupational exposure limit. More than half of the identified gases do not even have any occupational exposure limit specifications. Because of the expected dilution at the height of the operating distance (the surgeon's nose), the present measured concentrations do not allow any conclusion on a direct health danger to the operating team. Because of laser spectroscopy, the present work reveals not only the involved gases but also their respective concentrations near the point of origin. These data are prerequisite for further studies, which are mandatory, verifying the effective concentrations of the inhaled gases.

Air Pollutants, Occupational↗