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PubMed1993

Impact of organochlorine pesticide residues and PCBs on otters (Lutra lutra): a study from western Britain.

A study of otter (Lutra lutra) populations and levels of organochlorine (OC) pesticide residues and PCBs in otter droppings (spraints) was made on eight stretches of river in three catchments in Wales and West Midland England. Population and contaminant levels were compared against target values. The otter populations (as measured by an index) remained stable on one stretch over 11 years, while they increased rapidly to equilibrium on four other stretches. The three lower stretches of rivers showed more erratic trends and on only one stretch did the index exceed, occasionally, the target value. Marking intensity at spraint sites was also lower at the three lowland sites. Concentrations of dieldrin, DDE and PCBs were significantly greater in spraint samples from the three lowland stretches. Over 50% of samples from the three lowland stretches had OC concentrations above the maximum allowable concentration, whereas most samples from the upland stretches had concentrations below the 'no effects level'. It is suggested that the colonization, by otters, of their former lowland range is inhibited by OC contamination of their food chain but, if contaminant levels can be reduced, spread will occur rapidly.

Animals↗
PubMedDate not supplied

[The validation of the maximum permissible concentration of pyromellitic dianhydride in the atmosphere].

The maximum allowable concentration (MAC) of pyromellitic acid dianhydride (PMAD) in the ambient air was substabtiated by physiological, hematological, and physiological methods. The inhalation of this substance by animals reduced their body weight, erythrocytic osmotic resistance, enhanced animals' sensitization. The mean daily MAC of PMAD was found to be 0.01 mg/m3. PMAD was considered to be Hazard Class 2.

Administration, Inhalation↗
PubMed1979

[Modular way of sampling for determination of the degree of occupational exposure at industrial plants with periodically changing dust concentration].

A work station with dustiness changing periodically during a workshift is one of the most common types of work stations, as regards exposure dynamics. Cyclic significant concentrations of dust occurring from time to time result from a specific technological treatment used. The measuring module will be the time of measurement, starting with the beginning of the cycle of working out a given detail or--the technological process through the whole treating and technological process as well as breaks--due to various reasons--until starting another, analogous operation. What was found is that average dust concentrations obtained from modular measurements correspond to average concentration to which an employee is exposed during the whole workshift. Modular measurements allow to reconstruct work conditions inducing silicosis, and may be helpful in settling the maximum allowable concentration.

Air Pollutants↗
PubMed2005

[Progress of biological air filter (BAF) development in manned spacecraft cabin].

The contaminants originating from human metabolism, material off-gassing and waste processing, may influence human health and the growth and development of higher plants when they accumulate at some degree in the spacecraft cabin. So the contaminants concentrations must be controlled below the spacecraft maximum allowable concentration (SMAC). For the long manned space missions and planetary habitation, biological technique is available for the removal of the contaminants. The biological air filter, BAF, is a system that degrades the contaminants into carbon dioxide, water and salts. It holds many advantages such as small weight and volume, low power consumption, easy maintenance and good working performance under the condition of microgravity. Its wide application will be seen in the space field in near future.

Air Conditioning↗
PubMed2004

Cross-sectional study of cardiovascular effects of carbon disulfide among Chinese workers of a viscose factory.

OBJECTIVE: This cross-sectional study investigates the cardiovascular effects among Chinese workers who were occupationally exposed to carbon disulfide (CS2), and evaluates the protective value of the current Chinese Maximum Allowable Concentration (MAC) of CS2 against cardiovascular effects. METHODS: The measurements of exposure were performed by personal sampling and gas chromatography. The biological monitoring was performed by HPLC. Three hundred and sixty-seven exposed workers and 125 reference workers (never exposed to CS2,) were included in this study. The exposed workers were divided into 2 sub-groups according to their cumulative exposure indices, the cut-off point being at 100 which means 10 years exposure to the Chinese Maximum Allowable Concentration in the workplace (10 mg/m3). All subjects were examined using a self-administered questionnaire including medical and job history, clinical complaints in the previous three months, and underwent a clinical check-up and a 12 lead electrocardiography (ECG) at rest, coded according to the Minnesota code. Blood pressure (BP) was recorded and blood samples were collected for lipid measurements. RESULTS: The personal monitoring showed that the exposures levels (15.47 +/- 2.34 mg/m3) were below the Threshold Limit Value (TLV, 31 mg/m3), and most of the samples analyzed still showed higher values than the Chinese MAC (10 mg/m3). Clinical complaints and abnormal electrocardiograms were not significantly increased in exposed workers. No significant effect of CS2 on blood pressure, cholesterol, HDL and LDL cholesterol or triglycerides was found. Further studies are recommended to elucidate the mechanism of cardiac intoxication after CS2 exposure. CONCLUSION: This study showed that Chinese workers exposed to CS2 did not have more clinical complaints, nor more ECG abnormalities than controls and no adverse effects were found in their lipids at an exposure level below the current TLV. The present results indicate that differences of health effects reported worldwide are possibly due to different exposure levels. They also indicate that the current Chinese MAC (10 mg/m3) sufficiently protects workers against negative cardiovascular effects.

Adolescent↗
PubMed1993

[A study of hygienic standard for titanium in the source of drinking water].

The smell and taste thresholds of titanium in water were tested. The results indicated that the concentration of smell and taste thresholds for Titanium were 4.329mg/L and 3.332mg/L respectively. The threshold below value of autopurification was 0.1mg/L. The toxicity assessment showed that the acute toxicity of titanium by oral route was of low order according to the toxicity classification. There was no obvious cumulative effect, nor was there mutagenesis demonstrable. Chronic toxicity test of titanium in rats showed that the maximum non-effective concentration was 1.08mg/L. It is suggested that the maximum allowable concentration of titanium in drinking water may be 0.1 mg/L.

Animals↗
PubMed2000

Analytical control of preservative labelling on skin creams.

Contents of 23 preservatives (22 permitted and 1 non-permitted) were analysed in 67 skin creams to verify whether these products complied with the Cosmetic Directive with respect to ingredient labelling, as well as with respect to maximum allowed concentrations of the respective preservatives. The preservatives selected for the analysis were: parabens, 2-phenoxyethanol, benzoic acid, 4-hydroxybenzoic acid, sorbic acid, salicylic acid, formaldehyde and formaldehyde releasers, 3:1 mixture of 5-chloro-2-methyl-4-isothiazolin-2-one and 2-methyl-4-isothiazolin-2-one (Kathon CG), 2-bromo-2-nitropropane-1,3-diol (Bronopol), 5-bromo-2-nitro-1,3-dioxane (Bronidox) and methyldibromo glutaronitrile. 1 or more parabens were present in 87% (n=58) of the investigated products, 2-phenoxy ethanol in 49% (n=33) of the products, and formaldehyde/formaldehyde releasers were present in 51% (n=34) of the products. Kathon CG was found in 3 products, acid preservatives (except salicylic acid) in 8 products, Bronopol in 5 products, and methyldibromo glutaronitrile was present in 4 products. The contents of all of the target preservatives in the skin creams were within the maximum allowed concentrations of the respective substances. Incorrect ingredient labelling with respect to paraben content was found in 10% (n=7) of the investigated products, 33% (n= 22) of the products were not declared for the content of formaldehyde/formaldehyde releaser, and 7% (n=5) products were incorrectly labelled for the content of 2-phenoxyethanol. In 1 of the products containing Kathon CG, the ratio of 5-chloro-2-methyl-4-isothiazolin-2-one to 2-methyl-4-isothiazolin-2-one (1.4:1) was not correct. 4 of the 8 products containing acid preservatives were not labelled for the content of these substances. All in all, in 45% (n=30) of the investigated skin creams ingredient labelling was incorrect with respect to preservative contents. The proportion of incorrect labelling is reduced to 23% (n = 15), when the formaldehyde content in skin creams below 30 ppm is not accounted.

Chromatography, High Pressure Liquid↗
PubMed2003

Ecotoxicological study of Lithuanian and Estonian wastewaters: selection of the biotests, and correspondence between toxicity and chemical-based indices.

The toxicity of industrial and urban wastewater (WW) samples collected in Lithuania and Estonia was evaluated by using a suite of biological tests comprising the Algaltoxkit F with Selenastrum capricornutum, the Charatox with Nitellopsis obtusa, Daphtoxkit F with Daphnia magna, Thamnotoxkit F with Thamnocephalus platyurus, Protoxkit F with Tetrahymena thermophila and the Microtox with Vibrio fischeri. The Charatox and Thamnotoxkit F tests showed highest relative sensitivity, responding to 80-90% of samples, respectively, and both expressed good discrimination capacity between samples. Principal Component and pairwise correlation analysis allowed to select test-battery consisting of Charatox, Thamnotoxkit and Microtox. The WW toxicity was evaluated by means of cumulative indices such as average toxicity (AvTx) and two indices derived from the PEEP-index (Environ. Toxicol. Water Qual. 8 (1993) 115). In addition to these integrated evaluations of test-battery response, WW toxicity was evaluated according to the most sensitive test (MST) in the battery. The linear regression analysis between cumulative toxicity indices and chemical-based indices (derived from comparison of WW chemical concentrations and their respective maximum allowable concentration) revealed positive linear relationships (r(2)=0.7-0.8), while toxicity evaluation based on the MST was less positively related with chemical analysis data (r(2)=0.5-0.6). Although better coincidence between the toxicity and chemical-based assessments was achieved when information from all tests in the battery was assembled, the prediction of toxicity from chemical data was still limited. In search of suitable test-battery for the screening of certain type of WWs, a preliminary study comprising excessive suite of tests might be useful.

Animals↗
PubMed1991

[Effect of simultaneous exposure to fluorine and manganese on health status of workers].

The effect of fluorine and manganese on the health of workers continually exposed to these elements was studied. The concentration of the chemicals did not significantly exceed maximum allowable concentrations only during three hours of work daily. Thirty-six workers directly exposed to fluorine and manganese were examined and compared with the controls. The authors demonstrated that exceeding permissible norms did not cause evident intoxication symptoms even though working in exposure had lasted for many years. However, some changes in the activity of liver indicatory enzymes may be one of the first symptoms of this organ's damage. Frequently occurring ++periodontosis and leukoplakia of the mucous membrane needed careful stomatological prophylaxis .

Adult↗
PubMed2001

Effect of benzene, toluene, xylene on the semen quality and the function of accessory gonad of exposed workers.

The effects on semen and the function of accessory gonad of workers after short and long term exposure to benzene, toluene, and xylene were examined. The semen and blood of 24 married workers exposed to benzene, toluene, and xylene were collected. Routine sperm characteristic, acrosin activity, and Lactate dehydrogenase C4 (LDH-C4) relative activity were detected. The results showed that benzene, toluene, and xylene were found in the blood and semen of some ex-workers at workplaces where the air concentration of benzene, toluene, and xylene exceeded the maximum allowable concentration (MAC). No such solvents were detected in the blood and semen of workers of the control group. The sperm vitality and sperm motility decreased in the exposed workers. The mean acrosin activity, gamma-GT activity and LDH-C4 relative activity in the exposed workers were lower, and fructose concentration was higher than those in the control. There were negative correlations between sperm vitality, sperm activity, acrosin activity, or LDH-C4 relative activity and working history. These results suggest that the mixture of these solvents could affect the sperm and the function of accessory gonad. This might be one reason of the abnormal pregnancy outcome among the wives of workers exposed to benzene, toluene, and xylene.

Acrosin↗
PubMed1999

Effect of benzene, toluene, xylene on the semen quality of exposed workers.

OBJECTIVE: To examine the effects on semen and sperm quality of workers after a short and long term exposure to benzene, toluene, and xylene. METHODS: The semen and blood of 24 married workers exposed to benzene, toluene, and xylene from shoemaking, spray painting, or paint manufacturing factories were collected. The concentration of benzene, toluene, and xylene in the blood and semen was determined by using headspace chromatographic method. Routine sperm test was carried out and acrosin activity detected. RESULTS: The results showed that benzene, toluene, and xylene were found in the blood and semen of some ex-workers in a working environment where the air concentration of benzene, toluene, and xylene exceeded the maximum allowable concentration (MAC). This result was not found in workers of the control group. There were also some effects on the quality of semen in the exposed workers. For example, the percentage of semen with liquefaction time exceeding 30 minutes increased. The sperm vitality, motility and acrosin activity decreased. At the same time, there were a positive correlation between liquefaction time and the level of toluene in semen, and a negative correlation between sperm vitality, sperm activity or acrosin activity and working history. CONCLUSIONS: The results suggested that the mixture could affect the quality of semen and sperm, which might be the main reason of the abnormal pregnancy outcome among the wives of workers exposed to benzene, toluene, and xylene. Further studies are, however, required to confirm these findings.

Acrosin↗
PubMed2006

Sorption of phosphorous to Filtralite-P--the effect of different scales.

Sorption of P to the filter material Filtralite-P was examined at a small, medium and large scale. In the small- and meso-scale laboratory models, the sorbed amount of total phosphorus (P) was heterogeneously distributed with more P sorbed in the inlet zone and the bottom layers. The full-scale system had, on the other hand, the highest sorbed concentration in the outlet region. The overall P sorption capacity of the material was 8030, 4990 and 521 mg P kg(-1) Filtralite-P for Box 1, Box 2 and meso scale, respectively. This equals 4.4, 2.8 and 0.29 kg P m(-3) material, respectively. However, the maximum sorption capacities found were 2500, 3887 and 4500 mg P kg(-1) Filtralite-P for the two small-scale box systems and the meso-scale container, respectively. In the full-scale system the overall P sorption capacity of the material was 52 mg P kg(-1) Filtralite-P (0.029 kg P m(-3) Filtralite-P with a maximum sorbed amount of P of 249 mg P kg(-1). Results from both the small- and meso-scale system show that when a constructed wetland (CW) is saturated, i.e. when the outlet concentration has reached its maximum allowed concentration of 1.0 mg P l(-1), only parts of the filter material will have reached the sorption capacity. Sequential extractions of Filtralite-P showed that the loosely bound P, Ca-P and Al-P were the primary P sorption pools both in the small-scale models and in the full-scale CW. However, the proportion of these three fractions varied with time and change in pH. A white product precipitated in the outlet zone of both the small-scale box models as well as the onsite CW. The surface of these precipitation particles was identified by X-ray diffraction and SEM method as CaCO3 and precipitated Ca- and Mg-phosphates.

Filtration↗
PubMed1994

Volatile organic contaminants found in the habitable environment of the Space Shuttle: STS-26 to STS-55.

The health and performance of spacecraft crews can be adversely affected by contaminants present in the respirable air. Contaminants originate from hardware offgassing, crew and microbial metabolism, use of utility chemicals, leakage from fluid systems and payload experiments, and from electrical overheating. The quality of Shuttle air is measured by collecting contaminants in evacuated cylinders or on sorbent resin for later ground-based analysis by gas chromatography (GC) and GC mass spectrometry (MS). The results of those analyses are presented for 28 missions, including 5 Spacelabs which were flown in the payload bay of the Shuttle. The major contaminants were relatively nontoxic alcohols (ethanol, isopropanol), ketones (acetone, diacetone alcohol), alkanes, halocarbons (Halon 1301, Freon 113), and siloxanes. Occasionally, more toxic contaminants, such as methanol, acetaldehyde, and tetrachloroethene, were present at low concentrations (below 1 mg/m3). The contaminant concentrations measured in spacecraft air were compared to spacecraft maximum allowable concentrations (SMAC's) which are set to protect the crew from adverse health effects or performance decrements. Aggregate toxicity assessments (T values) of the contaminants present during each mission, calculated by summing the ratios of measured concentrations to each contaminant's SMAC, showed that air quality consistent met the criterion that the T value be less than 1.

Air Pollution, Indoor↗
PubMed2004

Heavy metals in drinking waters from Mount Amiata (Tuscany, Italy). Possible risks from arsenic for public health in the Province of Siena.

Concentrations of As, Al and some heavy metals (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb) were measured in drinking waters from Siena and Grosseto districts, South Tuscany, Italy. The analysis, performed mostly by electrothermal activated atomic absorption spectroscopy equipped with graphite furnace, and in some cases high-resolution inductively coupled plasma mass spectrometry, indicated that concentrations of the elements were generally far below the maximum allowed concentration (MAC). However, the concentration of As in some of the waters at sources or at the terminals of the water webs was relatively high (largest value, 14.4(2) microg/l) when compared to the MAC(As) value (10 microg/l, December 25, 2003; Italian Law). Relatively high concentrations of some metals had been detected in a few samples from the ends of the distribution webs, when compared to values at sources. These effects are probably due to leaching from metal pipes. A general 'metal index' (MI) for drinking water, which takes into account possible additive effects of N heavy metals on the human health that helps to quickly evaluate the overall quality of drinking waters, is introduced in this paper as MI=?(i=1,N)[C(i)/(MAC)(i)]. Samples from Ermicciolo spring and Siena water web had MI values of 1.1 and 1.3, respectively, showing that the quality of drinking water in town is somewhat worse than that at one of the main sources, at least regarding the 12 elements taken into account.

Arsenic↗
PubMedDate not supplied

[Mitotic cycle of a HeLa cell culture exposed to the maximum permissible concentrations of trace elements].

It is shown that administration of certain trace elements in maximum allowable concentrations induces changes in metabolism and functionation of cells in the culture. Zinc, nickel, cobalt, cadmium and fluorine are stated to inhibit mitotic activity of HeLa cells by the end of 24 hours of their action. Parallel with this they promote a decrease in H3-thymidine incorporation into DNA. Besides these substances delay various stages of the mitotic cycle for cells.

Autoradiography↗
PubMed1984

Indoor air pollution by smoke constituents--a survey.

A review of the literature on the present state of knowledge about the topic "indoor air pollution by smoke constituents" has been made. While consideration is given to standard bibliographic works and more recent reviews, an evaluation of the results of field studies and experimental investigations carried out under realistic conditions is also made. The selection of the tobacco smoke constituents discussed here was based on environmental and toxicological aspects. The following substances are considered in detail: carbon monoxide, nitrogen oxides, formaldehyde, acrolein, ammonia, phenol, hydrogen cyanide, sulfur dioxide, cadmium, nickel, nicotine, some volatile nitrosamines, polycyclic aromatic hydrocarbons, and respirable particulates. The smoke constituent concentrations in the literature are presented in tables. The results are evaluated and discussed with respect to the maximum allowable concentrations presently valid in the Federal Republic of Germany.

Acrolein↗