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PubMed2006

Persistent organic pollutants in moss as bioindicators of atmospheric pollution in Singapore.

Moss samples were collected from the island of Singapore and analysed for a range of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). Although all compounds analysed have been banned from use in Singapore, they were detected in all samples collected. Among the hexachlorocyclohexanes (HCH), beta-HCH was the most dominant isomer, while trans-chlorane was found to be the most dominant cyclodiene pesticide. High levels (79.12 ng g(-1)) of PCBs were detected in mosses collected from a nearby island due to active accumulation of pollutants associated with boat emissions. Significant spatial variations in the levels of organic pollutants in Singapore were largely absent, indicating that air masses moving over the island deposit OCPs and PCBs in a uniform pattern. A comparison of moss pollutant levels with available data from Czech Republic showed that dichlorodiphenyldichloroethylene (p,p'-DDE), dichlorodiphenyltrichloroethane (p,p'-DDT) and PCB levels in Singapore are the highest. The presence of these compounds suggests that they are still used in the region and are environmentally recalcitrant.

Air Pollutants↗
PubMed2007

Pollution sources and occurrences of selected persistent organic pollutants (POPs) in sediments of the Mekong River delta, South Vietnam.

The Mekong River delta is one of the largest agricultural land in the Southeast Asia. It plays a very important role for agriculture and fisheries in South Vietnam. However, comprehensive studies on the environmental pollution of persistent organic pollutants (POPs) in Mekong River delta have not been carried out in recent years. In this study, we collected sediment samples from the Mekong River to evaluate the contamination and ecological risks caused by several POPs. The contamination pattern of POPs was DDT>PCBs>CHLs>HCHs>HCB. DDTs are the most abundant pollutants, their concentration ranging from 0.01 to 110 ng/g dry wt, followed by PCBs (0.039-9.2 ng/g dry wt). DDTs and PCBs concentrations were higher in sediment from adjacent to urban areas than those from rural and agricultural sites, suggesting urban areas as important point sources of DDTs and PCBs to the river. Ratio of p,p'-DDT/p,p'-DDE was lower compared to those previously reported. However, some samples still had the ratio higher than 0.5, indicating recent input of DDT into the aquatic environments. This result shows that although the magnitude of contamination decreased over time, recent inputs of DDTs to the river still occur. Some sediment samples had concentrations of DDT compounds higher than the standards from the Canadian Environmental Quality Guideline, suggesting continuous monitoring for POPs contamination in the Mekong River is necessary.

Cities↗
PubMed1988

Prevalence of respiratory symptoms and diseases in schoolchildren living in a polluted and in a low polluted area in Israel.

Second and fifth grade schoolchildren living in two communities with different levels of air pollution were studied. The parents of these children filled out ATS-NHLI health questionnaires. The prevalence of reported respiratory symptoms and pulmonary diseases was found to be significantly higher among children growing up in the polluted community (Ashdod) as compared with the low-pollution area (Hadera). Logistic models fitted for the respiratory conditions which differed significantly between both areas of residence also included background variables that could be responsible for these differences. Relative risk values, which were calculated from the logistic models, were in the range of 1.47 for cough without cold to 2.66 for asthma for children from Ashdod, as compared with 1.00 for children from Hadera.

Air Pollutants↗
PubMed2003

Impact of different pollutant sources on Shiraz air pollution using SPM elemental analysis.

Weekly average suspended particulate matter (SPM) concentrations were measured in four locations in Shiraz, Iran. Sampling was carried out from July 1999 and continued until July 2000. Instrumental neutron activation analysis (INAA) and atomic absorption spectrometry (AAS) methods were employed to obtain the weekly concentrations of Pb, Br, V, Ca, Al, Fe, Cu, Cr, Mn, Sc and Zn. The mean annual concentrations (in microg/m(3)) of 11 elements were found to be: Pb 0.545 (+/- 33.8%), Br 0.413 (+/- 34.1%), V 0.009 (+/- 28.2%), Ca 13.36 (+/- 24.5%), Al 2.56 (+/- 46.3%), Fe 2.62 (+/- 38.7%), Cu 0.122 (+/- 41.4%), Cr 0.015 (+/- 35.8%), Mn 0.053 (+/- 35.5%), Sc 0.0008 (+/- 37.5%) and Zn 0.085 (+/- 25.2%). The results of the study show that vehicle (traffic) pollution in Shiraz is higher than WHO and EPA standards and natural and industrial pollution is exceeding international guidelines in some seasons. The findings of the study confirm that the nearby cement factory has a major pollution impact on Shiraz air.

Air Pollutants↗
PubMed2002

The effects of elutriates from PAH and heavy metal polluted sediments on Crassostrea gigas (Thunberg) embryogenesis, larval growth and bio-accumulation by the larvae of pollutants from sedimentary origin.

The release, bio-availability and toxicity of contaminants, when sediments are resuspended have been examined, studying concurrently their effects on the embryogenesis and on the larval growth of the Crassostrea gigas larvae and their bio-accumulation in those organisms. Three characteristic sediments have been selected (one contaminated by PAHs, a second by heavy metals and the last by the both pollutants). The organisms were directly exposed to elutriates obtained from each sediment or fed on algae (Isochrysis galbana) contaminated with the same elutriates. The elutriates used in this study show contamination levels similar to those observed in some polluted coastal and estuary environments. The larval growth test has appeared to be more sensitive that the embryotoxicity test. The biological effects and the contaminant bio-accumulation were more pronounced when larvae were directly exposed to different elutriates. In the case of PAHs, the contamination of algae was sufficient to lead to effect on the larval growth of the Crassostrea gigas. In all cases, a fraction of contaminants adsorbed on suspended particles was bio-available and accumulated by the larvae. This study has shown that resuspending polluted sediments constitutes a threat to pelagic organisms and than the C. gigas larval growth may be proposed as a test to protect the most sensitive areas.

Animals↗
PubMed1993

[Heavy metal pollution of soil and garden products of Stolberg home gardens and lead and cadmium pollution of small farms in Stolberg].

Cadmium, lead and zinc were determined in garden soils and vegetable products from private gardens located in a lead/zinc smelter area (Stolberg, Germany). At the same time lead and cadmium were measured in blood and urine samples collected from 90 garden owners. Inspite of extraordinary high levels of cadmium and lead in garden soils and vegetables, blood lead, blood cadmium and urine cadmium levels were not or only slightly elevated in the gardeners when compared to a reference group of subjects from the same area who did not consume home-grown vegetables and fruits. The results show that high levels of pollutants in soil and vegetables are not necessarily associated with an increased burden of pollutants in the human body, and that the transfer of pollutants from soil to humans might have been overestimated in some cases. Moreover, the results underline the preventive character of the guideline values presently applied with respect to the evaluation of soil contaminants.

Cadmium↗
PubMed1977

[The determination of resort and stress-areas by air pollution 2. communication: the evaluation of air pollution in spreadout areas, classification into stress-categories (authors transl)].

To qualify the air pollution by SO2 and particulate matter in wide spreaded areas a method for complex terrain was used in the Austrian Alps. The working model which was chosen is described in report 1. It is possible to classify the investigated area according to stress-categories by adjusting the data. For the qualification of results of measurements for dust fall the criterias were used according to KOFLER and BENGER. Two different situations were considered for the separation of limits for the stress-categories for SO2: areas which are polluted in first line by area sources, and areas which are polluted in first line by point sources.--The limits which were used in the study of Salzburg are introduced and discussed.--According to the method which is described above all municipalities of Tyrol and Salzburg were classified in stress-categories during to their air quality. The results are introduced.

Air Pollution↗
PubMed1989

Geochemical partitioning of Co, Cr, Fe, Sc and Zn in polluted and non-polluted marine sediments.

The partitioning of Co, Cr, Fe, Sc and Zn into three fractions (reducible by acidified hydroxylamine hydrochloride, oxidizable by acidified hydrogen peroxide, and the residual after the previous extractions) of Saronikos Gulf surface sediments was determined by using a sequential extraction technique. The metal concentrations were determined by Instrumental Neutron Activation Analysis. With the exception of Sc, the metal content in the reducible and oxidizable fractions increases in the polluted sediments near the Athens Sewage Outfall (ASO) and a Fertilizer Plant (FP). In the non-polluted sediments, the residual fraction is the most important carrier for all metals examined. Oxidizable Cr and Zn correlate well with the organic carbon content of the sediments, but the reducible fraction (mainly Fe/Mn hydroxides) is the most important sink for Co, Cr, Fe and Zn in the polluted sediments near the ASO. The pyrite-rich wastes from the FP are influencing the geochemical partitioning of the metals examined in the sediments in front of the FP and, partially, in the sediments near the ASO.

Journal Article↗
PubMed2003

Biological pollutants and biological pollution--an increasing cause for concern.

There are increasing concerns regarding the delivery, movement and presence of non-indigenous or invasive species into marine and estuarine areas. Such introductions can be on a large scale such as the movement to higher latitudes of species as the result of global warming. Alternatively, such species can be introduced into a marine or estuarine area as the result of small-scale events, such as the liberation from waste-water discharges, aquaculture or ballast-water discharge. However, if such introductions lead to a successful colonisation then they can become a wide-scale problem. This paper considers the introduction of such non-indigenous and invasive species as biological pollution and biological pollutants and it discusses the definitions and concepts used in assessing and managing marine pollution in relation to these terms.

Animals↗
PubMed1998

Response of a grassland ecosystem to air pollutants. VI. The chemical climate: concentrations and potential flux densities of relevant criteria pollutants.

Of the so-called criteria air pollutants, ozone (O3) and sulfur dioxide (SO2) are relevant to agriculture due to their known toxic (O3, SO2) and fertilizing (SO2) potentials. A proper entity to describe pollutant doses in dose-response relationships is the cumulative flux density absorbed by the respective receptor systems. For nutrient budgets the whole ecosystem acts as receptor; for toxicological considerations, stomatal uptake has to be considered primarily. In Central Europe, the atmospheric inputs of oxidized S (SO2, SO3(2-) and SO4(2-)) have declined from the past, and at present are generally below the nutrient requirements of agroecosystems. In contrast, the phytotoxic potential of O3 has increased during the last decade. Pollutant absorbed doses and weighted concentrations were used to describe the risk potential. It could be shown that these two differ significantly.

Journal Article↗
PubMed2000

Expression and inducibility of members in the cytochrome P4501 (CYP1) family in ringed and grey seals from polluted and less polluted waters.

The expression and inducibility of cytochrome P4501A (CYP1A) were investigated in hepatic microsomes of ringed seals (Phoca hispida) and grey seals (Halichoerus grypus) from polluted (Baltic Sea) and less polluted (Svalbard and Sable Island) areas. Liver CYP1A protein levels and activities were assessed by immunoblot analysis and determining catalytic activities towards ethoxyresorufin (EROD) and pentoxyresorufin (PROD). The amount of CYP1A apoprotein and its catalytic activity were increased up to 5-fold in Baltic ringed and grey seal populations in comparison with ringed seals from Svalbard and grey seals from Sable Island. EROD and PROD activities correlated in all seal groups, indicating catalysis by the same CYP form(s). Enzyme kinetic studies suggested that PROD activity is catalysed by CYP1A enzymes in both ringed and grey seals. In immunoblot analysis, a protein was revealed in liver with an antibody against human CYP1B1, indicating that a CYP1B1 like protein could be present in ringed and grey seals. In conclusion, these data strengthen the concept that CYP1A is markedly induced in seals living in polluted waters and that both EROD and PROD activities are mediated by CYP1A forms in the seal liver. In addition, this study provides the first evidence for the presence of a CYP1B like protein in seal liver.

Journal Article↗
PubMed2006

Relation between individual tree mortality and tree characteristics in a polluted and non-polluted environment.

UNLABELLED: Data on individual tree mortality in relatively healthy (Berezinskiy biosphere reserve) and damaged (surroundings of the mineral fertilizer plant 'Achema') even-aged Scots pine (Pinus sylvestris L.) stands are presented. Tree size and competition intensity were found to be the most significant predictors of individual tree mortality in all age groups of the relatively healthy Scots pine stands, however, an essential reduction in the closeness of relations between the tree mortality rate and these variables was determined with the aging of stands. An exponential decrease in tree mortality probability with an increase of tree size is characteristic for trees suffering different competition intensity, however, this decrease becomes much more pronounced as the competition pressure increases. The relations of different tree and stand variables with tree mortality probability have been found to become much weaker in the polluted environment. An exponential increase in tree mortality probability with an increase of crown defoliation was characteristic of damaged Scots pine stands, however, the rate of the increase was different in different age and diameter classes. The impact of crown defoliation on tree mortality rate increased with the aging of stands. At the same defoliation level, individual tree mortality probability was much higher for smaller suppressed trees, however, a relative increase in tree mortality probability along with an increase of crown defoliation was more pronounced for dominant trees. CONCLUSION: a higher mortality of damaged (defoliated) trees should be considered while assessing losses in forest productivity in a polluted environment.

Air Pollutants↗
PubMed2000

The National Morbidity, Mortality, and Air Pollution Study. Part II: Morbidity and mortality from air pollution in the United States.

BACKGROUND: Epidemiologic time-series studies conducted in a number of cities have identified, in general, an association between daily changes in concentration of ambient particulate matter (PM) and daily number of deaths (mortality). Increased hospitalization (a measure of morbidity) among the elderly for specific causes has also been associated with PM. These studies have raised concerns about public health effects of particulate air pollution and have contributed to regulatory decisions in the United States. However, scientists have pointed out uncertainties that raise questions about the interpretation of these studies. One limitation to previous time-series studies of PM and adverse health effects is that the evidence for an association is derived from studies conducted in single locations using diverse analytic methods. Statistical procedures have been used to combine the results of these single location studies in order to produce a summary estimate of the health effects of PM. Difficulties with this approach include the process by which cities were selected to be studied, the different analytic methods applied to each single study, and the variety of methods used to measure or account for variables included in the analysis. These individual studies were also not able to account for the effects of gaseous air pollutants in a systematic manner.

Adolescent↗
PubMed2005

Assessing the cost of groundwater pollution: the case of diffuse agricultural pollution in the Upper Rhine valley aquifer.

This paper presents an assessment of the costs of diffuse groundwater pollution by nitrates and pesticides for the industrial and the drinking water sectors in the Upper Rhine valley, France. Pollution costs which occurred between 1988 and 2002 are described and assessed using the avoidance cost method. Geo-statistical methods (kriging) are then used to construct three scenarios of nitrate concentration evolution. The economic consequences of each scenario are then assessed. The estimates obtained are compared with the results of a contingent valuation study carried out in the same study area ten years earlier.

Agriculture↗
PubMed1993

[The concept of environmental pollution for emission control in regulating carcinogenic air pollutants in outdoor air].

The Conference of Ministers for the Environment commissioned a working group of the Länder Committee for Immission Protection to develop a concept of guidelines for the concentration of carcinogenic pollutants in the atmospheric aerosol. Of the large number of substances which have been identified as carcinogenic, seven were selected (arsenic, asbestos, benzene, cadmium, diesel exhaust, polynuclear aromatic hydrocarbons and 2,3,7,8-tetrachlorodibenzo-(p)-dioxin). These substances are emitted into the environment by amounts that are quantitatively of special importance for immission control. There are standardised measuring procedures for controlling them and their toxicological data base permits a quantitative assessment of cancer risk. The quantitative risk assessment by the working group was based on the WHO's "unit risk" model. It was decided that for evolving the guidelines the total cancer risk for all carcinogenic air pollutants be limited while at the same time the possible risk attributed to each individual substance should be reduced according to its contribution to the actual total cancer risk. The synthetic model developed by the working group is explained in detail and the resulting guidelines for an acceptable total cancer risk of 1:1000, 1:2500 und 1:5000 are stated.

Air Pollutants↗
PubMed1996

Phase I and II enzymes and antioxidant responses in different tissues of brown bullheads from relatively polluted and non-polluted systems.

Brown bullheads (Ameiurus nebulosus) were collected from the St. Lawrence River and compared in their detoxication capacities to bullheads from a relatively non-polluted aquatic system, Lac La Pêche. The content of polychlorinated biphenyls (PCBs) in white muscle was significantly higher (22-fold) in bullheads from the St. Lawrence River compared with those from Lac La Pêche. Activities of liver ethoxyresorufin O-deethylase (EROD), a common Phase I enzyme, were 2.8-fold higher in St. Lawrence River bullheads than in fish from La Pêche. Conjugation activity by hepatic glutathione S-transferase (GST) was 3-fold higher in the St. Lawrence River fish, and significantly higher activities were also detected in kidney and white muscle in these fish as compared with the Lac La Pêche group. UDP-Glucuronosyltransferase (UDPGT) activities in liver and kidney did not differ between the two groups. Activities of cytosolic superoxide dismutase (SOD) were significantly higher, while lower activities of catalase (CAT) in kidney and glutathione peroxidase (GPX) in red and white muscles were noted in the St. Lawrence River bullheads. Concentrations of total glutathione (TGSH) in the different tissues revealed significantly lower levels in liver, kidney and white muscle of bullheads from the St. Lawrence River. The changes in Phases I and II enzymes and TGSH levels in the various tissues relate to higher PCB concentrations of muscle tissue and suggest activation of detoxication capacities, but weakened antioxidant status in the bullheads from the polluted area. The results implicate the involvement of white muscle along with liver and kidney in the whole fish detoxication process.

Animals↗
PubMed2004

Effects of moderate pollution on toxic and trace metal levels in calves from a polluted area of northern Spain.

This study evaluated the contribution of anthropogenic pollution to toxic metal residues (Cd, Pb and As) in cattle in an industrialized area of Asturias (northern Spain), and investigated possible implications of toxic metal exposure for metabolism of essential metal elements (Cu, Zn, Fe, Mn). Samples of liver, kidney, muscle and blood from animals aged 9-12 months were obtained from an industrialized area (78 calves) and from a rural area (92 calves). Samples were acid-digested, and levels of metals determined by atomic absorption spectrophotometry. Cadmium and lead contents in the liver and kidney were moderately and significantly higher in calves from the industrialized area (Cd: liver 29.6, kidney 161; Pb: liver 38.1, kidney 38.3 microg/kg wet weight) than in calves from the rural area (Cd: liver 22.9, kidney 96.4; Pb: liver 20.7, kidney 15.9 microg/kg kg wet weight). Although these toxic metals were only moderately raised, our results suggest that they may nevertheless have interfered with trace element metabolism, as reported previously for severely polluted regions. Notably, copper levels in calves from the industrialized area were generally low, and nearly half of these animals showed tissue copper levels indicating risk of copper deficiency.

Animals↗
PubMed1986

A study of the atmospheric lead pollution in Seville, Spain. Influence of meteorology and traffic, and relationship with other traffic-generated pollutants.

A study of the atmospheric pollution by suspended particulate lead in the city of Seville, Spain, was carried out during the period between March 1983 and February 1984. The results obtained from seven sampling stations allowed us to study the site to site variations; there are two locations with average annual concentrations higher than 2 micrograms X m-3. In one station, the meteorological and traffic effects and relationship with other traffic-related pollutants, were investigated. The regression analyses performed on the average monthly data have shown an inverse correlation with wind speed and temperature and a direct correlation with carbon monoxide and smoke concentrations, but no significant correlation was found with the lead deposition levels.

Air Pollutants↗