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PubMed2001

Influence of season and pollution on the antioxidant defenses of the cichlid fish acará (Geophagus brasiliensis).

The livers of Geophagus brasiliensis collected from both a non-polluted site and a polluted site were analyzed for different antioxidant defenses, O2 consumption, thiobarbituric acid-reactive substance (TBARS) levels, and histological damage. Compared to controls (116.6 +/- 26.1 nmol g-1), TBARS levels were enhanced at the polluted site (284.2 +/- 25.6 nmol g-1), as also was oxygen consumption (86.6 +/- 11.3 and 128.5 +/- 9.8 micromol O2 min-1 g-1, respectively). With respect to enzymatic antioxidants, increased catalase activities (8.7 +/- 1.3 and 29.2 +/- 2.4 mmol min-1 g-1, respectively), unchanged superoxide dismutase activities (767.2 +/- 113.3 and 563.3 +/- 70.2 U g-1, respectively), and diminished glutathione S-transferase activities (29.0 +/- 3.2 and 14.9 +/- 3.2 micromol min-1 g-1, respectively) were detected. Reduced glutathione (1.91 +/- 0.17 and 1.37 +/- 0.25 mM, respectively), oxidized glutathione (1.50 +/- 0.20 and 0.73 +/- 0.17 mM, respectively), and total glutathione (3.40 +/- 0.26 and 2.07 +/- 0.27 mM, respectively) concentrations were also below control values at the polluted site. Nevertheless, the observed ethoxyresorufin-O-deethylase activities (1.34 +/- 0.11 and 16.7 +/- 0.21 pmol min-1 mg-1, respectively) showed enhanced values at the polluted site. The main histological damage observed in the hepatocytes from fish collected at the polluted site was characterized by heavy lipid infiltration. Fish collected at the end of spring showed higher O2 consumption, higher superoxide dismutase and glutathione S-transferase activities, and higher total and oxidized glutathione concentrations compared to the beginning of autumn. No seasonal changes were observed in catalase activities, glutathione or TBARS levels. Fish chronically exposed to relatively high pollution levels seem to be unable to set up adequate antioxidant defenses, probably due to severe injury to their hepatocytes. The higher antioxidant defenses found at the end of spring are probably related to the enhanced activities during high temperature periods in thermoconforming organisms.

Adaptation, Physiological↗
PubMed2006

[Pesticide pollution in water systems in a small rural community in Southeast Brazil].

Recent advances in analytical techniques allow identifying pesticide pollution in water systems. In small rural communities, the negative effects of pesticide pollution can be aggravated by the lack of infrastructure and adverse socioeconomic conditions. This study investigated pesticide pollution in potential water supply sources in a tomato growing area in Paty do Alferes, Rio de Janeiro State, Brazil. The study selected 27 points where five monthly samples were collected. Pesticide pollution was determined by analyzing acetyl-cholinesterase inhibition. In 19 of the 27 sample points, some pesticide pollution was detected, and in two points the pesticide pollution was above the permitted limits. The results thus proved the incidence of pesticide pollution in water sources in Paty do Alferes that could jeopardize the local population's health.

Agricultural Workers' Diseases↗
PubMedDate not supplied

[The EMECAS Project: Spanish multicentre study on short-term health effects of air pollution].

UNLABELLED: The EMECAM Project demonstrated the short-term effect of air pollution on the death rate in 14 cities in Spain throughout the 1990-1995 period. The Spanish Multicentre Study on Health Effects of Air Pollution (EMECAS) is broadening these objectives by incorporating more recent data, information on hospital disease admissions and totaling 16 Spanish cities. This is an ecological time series study in which the response variables are the daily deaths and the emergency hospitalizations due to circulatory system diseases and respiratory diseases among the residents in each city. Pollutants analyses: suspended particles, SO2, NO2, CO and O3. Control variables: meteorological, calendar, seasonality and influenza trend and incidence. STATISTICAL ANALYSIS: estimate of the association in each city by means of the construction of generalized additive Poisson regression models and metanalysis for obtaining combined estimators. The EMECAS Project began with the creation of three working groups (Exposure, Epidemiology and Analysis Methodology) which defined the protocol. The average levels of pollutants were below those established under the current regulations for sulfur dioxide, carbon monoxide and ozone. The NO2 and PM10 values were around those established under the regulations (40 mg/m3). This is the first study of the relationship between air pollution and disease rate among one group of Spanish cities. The pollution levels studied are moderate for some pollutants, although for others, especially NO2 and particles, these levels could entail a problem with regard to complying with the regulations in force.

Air Pollution↗
PubMed2006

Peroxisome proliferation and antioxidant enzymes in transplanted mussels of four basque estuaries with different levels of polycyclic aromatic hydrocarbon and polychlorinated biphenyl pollution.

We aimed to determine the effects of changes in polycyclic aromatic hydrocarbon (PAH) and polychlorinated biphenyl (PCB) bioavailability on peroxisome proliferation and antioxidant enzymes to assess their potential use as pollution biomarkers. For this, mussels (Mytilus galloprovincialis) were sampled in Txatxarramendi and transplanted to Arriluze, Muskiz, and Plentzia (northern Spain), and vice versa. Arriluze was the most heavily polluted site, followed by Plentzia, Txatxarramendi, and Muskiz. Animals transplanted from a polluted station to a cleaner station lost contaminant load in three to six weeks, and when transplanted to a more polluted station, they accumulated PAHs and PCBs accordingly. Peroxisomal acyl-A oxidase (AOX) activity was the highest in animals from Arriluze, and animals transplanted to Arriluze showed increased AOX activity, reaching the levels of native mussels. Mussels from Txatxarramendi showed the lowest peroxisomal volume density (Vvp). Among mussels from Txatxarramendi, only those transplanted to Plentzia showed increased Vvp, whereas animals from Arriluze and Muskiz transplanted to Txatxarramendi after 2 d and six weeks, respectively, had decreased Vvp. Two days after transplant, superoxide dismutase and glutathione peroxidase activities were significantly lower in mussels from Arriluze and Muskiz, respectively, than in those from Txatxarramendi and than in animals transplanted to Txatxarramendi from these stations. In conclusion, transplant experiments with mussels are useful to assess the effects of pollution. Peroxisome proliferation, measured as induction of AOX or increased Vvp, shows great potential as a biomarker of pollution to be included in pollution monitoring programs. In the present work, we have demonstrated that peroxisome proliferation is a reversible phenomenon in mussels.

Animals↗
PubMed2006

Genotoxicity in wood mice (Apodemus sylvaticus) along a pollution gradient: exposure-, age-, and gender-related effects.

We investigated the effects of environmental pollution on genetic damage in wood mice (Apodemus sylvaticus) by means of the comet assay, with special attention to the role of age and gender as potential confounding variables. The present study was carried out at four sites along a pollution gradient in the vicinity of Antwerp (Belgium), with a nonferrous smelter as the main pollution source. We measured the concentration of heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Pb, and Zn) in mouse liver and kidney and the concentration of organochlorine compounds (polychlorinated biphenyls and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene) in mouse muscle tissue to assess individual exposure. Cadmium exposure was very high at the sites closest to the smelter, and exposure to this metal decreased with increasing distance from the smelter. Exposure to the other pollutants was low to moderate at the different sites. Genetic damage was higher in mice from populations in the vicinity of the nonferrous smelter compared with that in the control populations. A significant increase in genetic damage with age was observed at the most polluted sites, but not at the control sites. Genetic damage was higher in male mice than in female mice at the most polluted site, but not at the other areas. Yet, no obvious relationship was found between individual pollutant levels and individual genetic damage levels. We conclude that the comet assay can be used to compare genotoxicity at the population level if the confounding variables of gender and age are taken into account. However, its use for individual health risk assessment remains questionable.

Age Factors↗
PubMed2006

Effects of pollution on human growth and development: an introduction.

Pollution is a worldwide problem and its potential to influence the physiology of human populations is great. Studies of human growth and development in relation to pollution have increased in number and quality since the mid-twentieth century. Many studies have found that some pollutants have detrimental effects on human growth, particularly prenatal growth. The heavy metal, lead, is commonly found in human populations and is related to smaller size at birth and studies have reported decrements that range up to about 200 grams. Noise stress from transportation sources also is related to reduced prenatal growth with somewhat smaller decrements reported. Studies of humans exposed to polychlorinated biphenyls, one of the persistent organic pollutants, have reduced size at birth, advanced sexual maturation and altered hormone levels related to thyroid regulation. Thus different pollutants exert effects through different physiological pathways. However, some studies have not observed these effects, which indicates that the situation is complex and requires further study with better study designs. Determining the effects of pollutants on human physiology and growth is difficult as it requires fairly large numbers of subjects who are not purposely exposed but for whom exposure can be measured. These effects of pollutants and the mechanisms of effect require further study to understand and, it is hoped, to blunt or block any detrimental effects on human health and well-being.

Adolescent↗
PubMed2001

Renal tubular dysfunction in male inhabitants of a cadmium-polluted area in Toyama, Japan--an eleven-year follow-up study.

An eleven-year follow-up study was carried out to elucidate the changes in the level of environmental exposure to cadmium (Cd) from rice after soil replacement of polluted paddy fields and these effects on urinary excretion of Cd in male inhabitants of a Cd-polluted area in Toyama, Japan. In addition, the prevalence of renal tubular dysfunction (RTD) was examined to clarify the progress of Cd-induced RTD. One hundred and twenty-seven male inhabitants born between 1914 and 1929 in 11 districts of the Cd-polluted Jinzu River basin and 31 reference subjects in 2 adjacent districts were examined twice in 1985-86 and 1996-97. The geometric means of Cd concentrations in polished rice (Cd-R) in the Cd-polluted areas were 0.18 ppm in 1985 and 0.21 ppm in 1986; these values were significantly higher than those of the reference areas (0.13 ppm in 1985 and 0.12 ppm in 1986). After 11 years, the Cd-R levels were significantly decreased to approximately half (0.08 ppm in 1996, 0.12 ppm in 1997) due to soil replacement of polluted paddy fields, which has been carried out since 1980. The mean Cd levels in urine (Cd-U) were significantly reduced from 7.9 and 9.5 microg/g creatinine in the initial study to 6.9 and 6.8 microg/g creatinine in the follow-up study. However, the prevalence of RTD, which was determined by urinary beta2-microglobulin exceeding 1 mg/g creatinine and urinary glucose exceeding 150 mg/g creatinine, increased from 18 and 23% in the 1985-86 study to 25 and 32% in the 1996-97 study, and a total of 12 new cases (12%) of RTD were found. Whereas, only one subject (4%) in the reference control areas was identified as RTD. Cd-induced RTD was prevalent, progressive and irreversible for male inhabitants of the Cd-polluted Jinzu River basin, although the environmental exposure to Cd through rice was significantly reduced by soil replacement of polluted paddy fields.

Aged↗
PubMed1991

Indoor air pollution: an edifice complex.

The collision of escalating technological sophistication and surging environmental awareness has caused the reexamination of many societal paradigms. Horror stories about lethal chemical exposures involving isolated cases of ignorance, carelessness or greed have caused the public to demand constant vigilance to prevent exposure to potentially hazardous substances. Accordingly, much time and resource has been expanded by the U.S. government and citizens to abate and prevent air and water pollution. While these efforts have met with measurable success, there is increasing public concern about a new generation of pollution-related human illness in office, home and transportation environments. New instances of Sick Building Syndrome or Building Related Illness are reported daily by the popular press. Human health effects such as cancer, infectious disease, allergy and irritation have been ascribed to indoor air pollution. The clinical aspects of indoor air pollution are often discounted by consulting engineers and industrial hygienists involved in indoor air quality. Physicians and clinically-trained scientists have received a "Macedonian call" to sift clinical relevance from the emotional aspects of indoor air quality problems. Point sources of pollutants, associated human health effects, and problem solving approaches associated with indoor air pollution are described. Regulatory and litigational aspects of indoor air pollution are also discussed.

Air Pollution, Indoor↗
PubMed1996

Bronchial asthma and air pollution at workplaces.

OBJECTIVES: This case-referent study was performed to investigate the possibility of nonspecific air pollution at workplaces increasing the risk of bronchial asthma for formerly healthy adults. METHODS: Seventy-nine cases of asthma, diagnosed at a lung clinic, among persons aged 20-65 years were compared with 304 referents drawn randomly from the population of the catchment area. Questionnaire information was obtained regarding occupation, exposure to suspect allergens, place of residence, smoking habits, and atopy. The subjects' occupations were categorized into four air pollution classes based on how the referents reported air pollution in their respective occupations. RESULTS: Three years or more of work in air-polluted occupations resulted in an odds ratio of 3.0 (OR) (95% confidence interval 1.5-6.1) in a comparison with work in occupations with slight or no air pollution. Stratification of the material for smoking habits or atopy did not alter the results. Nor did the exclusion of specific exposures to asthmatogenic agents such as ioscyanates, stainless steel welding, or aluminum salts change the effects of the nonspecific air pollution at workplaces. Smoking per se was associated with an almost doubled risk for asthma (OR 1.9, 95% confidence interval 1.1-3.4). CONCLUSION: The results of this study support an association between occupational exposure to nonspecific air pollution and the development of bronchial asthma.

Adult↗
PubMed1999

The effect of air pollution on infant mortality appears specific for respiratory causes in the postneonatal period.

To examine the association between individual lifetime measures of mean exposure to air pollution and postneonatal respiratory deaths, we have conducted a matched population-based case-control study covering all births registered in the Czech Republic from 1989 to 1991 that were linked to death records. For each case of infant death, we have randomly selected 20 controls from infants of the same sex born on the same day and alive when the case died. Exposure was assigned as the arithmetic mean of all 24-hour air pollution measurements in the district of residence of each case and control for the period between the birth and death of the index case. We used conditional logistic regression to estimate the effects of suspended particles, sulfur dioxide, and nitrogen oxides on risk of death in the neonatal and postneonatal period, controlling for maternal socioeconomic status and birth weight, birth length, and gestational age. There were 2,494 infant deaths with exposure data on at least one pollutant, 133 of them from respiratory causes. The effects of all pollutants were strongest in the postneonatal period and were specific for respiratory causes. For these, rate ratios for a 50 microg/m3 increase in particles, sulfur dioxide, and nitrogen oxides were 1.95 [95% confidence interval (CI) = 1.09-3.50], 1.74 (95% CI = 1.01-2.98), and 1.66 (95% CI = 0.98-2.81), respectively, after controlling for all covariates. Only particles showed a consistent association when all pollutants were entered in one model. We found no evidence of a relation between any pollutant and mortality from other causes. These results indicate that the effects of air pollution on infant mortality are specific for respiratory causes in the postneonatal period, are independent of socioeconomic factors, and are not mediated by birth weight or gestational age.

Air Pollution↗
PubMed1999

Outdoor air pollution in urban areas and allergic respiratory diseases.

Respiratory allergic diseases (rhinitis, rhinosinusitis, bronchial asthma and its equivalents) appear to be increasing in most countries, and subjects living in urban and industrialized areas are more likely to experience respiratory allergic symptoms than those living in rural areas. This increase has been linked, among various factors, to air pollution, which is now an important public health hazard. Laboratory studies confirm the epidemiological evidence that inhalation of some pollutants, either individually or in combination, adversely affect lung function in asthmatics. The most abundant air pollutants in urban areas with high levels of vehicle traffic are respirable particulate matter, nitrogen dioxide and ozone. While nitrogen dioxide does not exert consistent effects on lung function, ozone, respirable particulate matter and allergens impair lung function and lead to increased airway responsiveness and bronchial obstruction in predisposed subjects. However, besides acting as irritants, airborne pollutants can modulate the allergenicity of antigens carried by airborne particles. By attaching to the surface of pollen grains and of plant-derived paucimicronic particles, pollutants can modify the morphology of these antigen-carrying agents and after their allergenic potential. In addition, by inducing airway inflammation, which increases airway epithelial permeability, pollutants overcome the mucosal barrier and so facilitate the allergen-induced inflammatory responses. Moreover, air pollutants such as diesel exhaust emissions are thought to modulate the immune response by increasing immunoglobulin E synthesis, thus facilitating allergic sensitization in atopic subjects and the subsequent development of clinical respiratory symptoms.

Air Pollution↗
PubMed2001

The effects of particle size distribution on the settleability of CSOs pollutants.

Over the past decades, flocculation and/or sedimentation processes have been adopted to remove pollutants from CSOs. It has been learned that major factors affecting settlement of pollutants are the particle size distribution, their settling velocities and their specific gravity. It is, therefore, a good idea to analyze the particle size distribution and settleability of CSOs pollutants in order to develop details in designing a process. Discussed in this study are pollutant characteristics of CSOs such as particle size distribution and settleability of pollutants. The power law function is applied and is found to be an effective and reliable index for expressing the particle size distribution of pollutants in CSOs. Based on the particle size spectrum analysis, the tendency toward settling and simultaneous flocculation-settling phenomenon of CSOs pollutants is described. Based on the regression analysis it is observed that the derived constants of curves representing settling velocity profile are proportional to the initial concentration of particles and to the beta-values of power law distributions. It is also revealed that the simultaneous flocculation-settling processes are effectively described by the changes of the average particle diameter and of the beta-values of power law distributions.

Geologic Sediments↗
PubMed2002

Pollution based real time control of wastewater systems.

Wastewater systems are traditionally built as static systems to handle a design load. The real load varies, though, and hardly ever equals the design load. This implies that wastewater systems hardly ever operate in an optimum way, especially during wet weather. Real time control (RTC) of regulators can improve the operation by better fit of the system to the actual state and load. RTC based on pollutant concentrations together with hydraulic conditions (pollution based real time control, PBRTC) is investigated in this paper to assess the potential pollutant load reduction on receiving waters at wet weather without expansion of transport or storage capacity. Both CSOs and WWTP effluents contribute to the pollutant discharges to receiving waters and both are considered. Three cases are studied to assess the potential benefit of PBRTC. Giving priority to the most polluted wastewater for treatment and storage in branched interceptor systems can reduce CSO discharge loads by more than 20%. Biological WWTPs and especially activated sludge plants are more complex and less stable than chemical precipitation plants during and after high pollutant and hydraulic load. Biological plants can hence profit more from PBRTC than chemical precipitation plants. Receiving waters that are sensitive to acute effects caused by intermittent discharges can benefit more from PBRTC than receiving waters with problems connected to long-term accumulation of pollution.

Chemical Precipitation↗
PubMedDate not supplied

Respiratory function and atmospheric pollution.

The effects of environmental pollutants on human health and, in particular, on the respiratory apparatus, can be studied fundamentally by means of epidemiological and controlled exposure studies. One epidemiological study has reported the results of research which compared pulmonary function in adults with the average annual concentration of major pollutants in 8 geographical areas of Switzerland; the results demonstrated a direct relationship between atmospheric pollution and a worsening of pulmonary function. Controlled exposure studies, on the other hand, document the effects of specific air pollutants. Ozone (O3) is a secondary pollutant produced in the atmosphere by photochemical reactions which exerts a potent antioxidant and peroxidant action on biomolecules, whether intra or extracellular, with the production of free radicals. Nitrogen dioxide (NO2) is found mainly indoors due to its being a product of combustion of kitchen gas--it possesses low reactivity and low solubility that allows its penetration to the periphery of the lungs; the harmful mechanisms induced by NO2 are not well understood and could differ from those of O3. Sulphur dioxide (SO2) is found above all outdoors and is documented to affect the respiratory function of asthmatic subjects at concentrations above 1 part per million (ppm) while it has a doubtful effect on healthy subjects. Suspended particulate matter (SPM) is one of the major pollutants present in the air that comes mainly from vehicle exhausts, especially diesel models. Although the epidemiological data indicates a close relationship with both cardiac and respiratory pathology, the biological mechanisms by which it exerts its toxicity are still not well established. The great variability in individual response to pollutants suggests the need for further sensitivity tests to be carried out: it is of importance to identify specific genes with a stabilising role in cellular protection against oxidative stress, that influence the production of chemical mediators of inflammation.

Air Pollutants↗
PubMed2003

Breeding performance of great tits (Parus major) along a gradient of heavy metal pollution.

The possible effects of heavy metal pollution on various breeding parameters of the great tit (Parus major) were studied at four study sites in a pollution gradient near a large nonferrous smelter in Belgium during three consecutive breeding seasons. Significantly more females interrupted their laying period near the pollution source than did females farther away. At the two most polluted sites, hatching success was significantly reduced compared to two lesser-polluted study sites. Overall breeding success was also significantly lower toward the factory complex. This lowered breeding success was caused not only by the decreased hatching success toward the pollution source but also by the significant difference in fledging success among sites. Although a clear relationship was observed between the exposure to heavy metal pollution and an impaired reproduction, not all reproductive parameters were affected. We found no significant differences in the onset of laying, clutch size, length of the incubation period, and the proportion of nests with low-quality eggs among sites. Although nest box occupancy was every year slightly lower toward the smelter compared to farther away, differences among study sites were never significant.

Animals↗
PubMed2003

[Tempo-spatial variation of non-point source pollutants in a complex landscape].

The occurrence of non-point source pollution, is not only related to its sources, landscape pattern, but also dependents on the factors such as soil erosion, rainfall, irrigation, surface and underground run-off. Thus non-point source pollution is characterized by in nature tempo-spatial variation. In this paper, the tempo-spatial variation of non-point source pollution due to nutrient salts in a complex landscape was studied by field water sampling and analysis. The results were as follow: 1. Spatial variability of all nutrient concentration in rainfall-deficit year was generally smaller than that in normal rainfall year with different level for different pollutants in a single period. 2. Spatial variability of solid particles in surface water was much marked than the other pollutants studied both in the rainfall-deficit year and in the normal rainfall year, while the smaller variation in different water periods of a year in the normal rainfall year. 3. Apparently, those areas with stable run-off had a small seasonal variation of non-point source pollution. However, large seasonal change occurred mainly in the upper reach of river where run-off changed seasonally, and/or where farmland dominated, as well as where point-source pollution occurred.

Agriculture↗
PubMed2004

Policy development for the reduction of pollution caused by traffic experiences from The Netherlands.

Road traffic is a diffuse source of heavy metals and oil that leads to pollution of verges and surface water in areas immediately surrounding roads. The Commission for Integrated Water Management (CIW) has drawn up a policy document addressing methods for managing this type of pollution. The document is based on results from numerous studies in The Netherlands targeting pollution caused by traffic. The Commission concludes that measures at the source are the only way to realise sustainable solutions. For example, attention should be devoted to the issue of zinc emissions from car tyres and crash barriers. The concept of controlled infiltration is recommended for combating pollution caused by spray and runoff from roads. This includes periodic chemical inspection of verge pollution and, where necessary, replacement of the verge's top layer. The application of porous asphalt on highways in The Netherlands has also proven highly effective in limiting pollution caused by traffic, with far less pollution caused by spray from the highway and runoff as compared to traditional asphalt.

Environment↗
PubMedDate not supplied

Regional differences in dietary intake of environmental pollutants in Japan.

In order to study regional differences in the dietary intake of environmental pollutants in Japan, we measured the daily intake ingested via food (the main route for pollutant intake) and analyzed the data by multivariate analysis. Daily mean samples were collected by the duplicate method from 25 women per area in 5 cities in both northern and southern Japan in July, 1987. Cadmium, lead, benzo(a)pyrene, hexachlorobenzene, DDT, chlordane isomers, and the total amount of the isomers were determined for typical pollutants. The data were statistically analyzed by multivariate analysis. Regional differences in the daily intake of environmental pollutants were studied by discriminant analysis. The eigenvalues of the functions 1 and 2, which accounted for 84.8% of variance, were 0.647 and 0.221, respectively. The function 1 was related to regional differences in the intake of environmental pollutants in the northern and southern regions of Japan. The statistical distance calculated from the intake of environmental pollutants correlated well with the geographical distance. The coefficients of the canonical discriminant function 1 were large in the order of lead (Pb) and the total amount of chlordane isomers (T-CLD). The regional difference was assumed to be due to the intake of Pb in the north and the intake of T-CLD in the south. Other pollutants, however, did not contribute to the observed regional difference. The study shows that performing multivariate analysis by computer provides a useful means for processing a large amount of data and can provide important information for data analysis in environmental health.

Adult↗