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High levels of endotoxin are found inside and near to animal houses. However, there is a lack of data on environmental endotoxin in areas with intensive animal production facilities. We conducted a cross-sectional study of respiratory health in two villages of Lower Saxony with intensive livestock production. We assessed the level of endotoxin exposure in the backyards of 32 participants with two 24-hours measurements of inhalable fraction (one in winter and one in summer). The geometric mean (geometric standard deviation) of the levels of endotoxin varied between 2.0 (2.9) EU/m3 in winter and 2.9 (2.4) EU/m3 in summer. Potential predictors - season, sampling sites, and weather conditions - explained 24% of the variability in ambient endotoxin concentration in the study area. The results indicate that, compared with urban residents, exposure to endotoxin is greater among people living in rural areas with intensive animal production. This might affect their respiratory health. However, these exposures are characterized by a large spatial variability.
The immunological effects of the environmental and/or occupational exposure to NO2 and NO in air as polluting gases have been examined in groups of 16 men. The determina-tion of NO2 and NO concentrations in ambient air in the work enviroment as well as in ambient air in residential areas of these men was performed, always by use of an Amaya-Sugiura passive sampling spectrophotometric method. Mean concentration of NO2 in ambient air in residential areas was 0.0210 mg x m-3 (0.0070 to 0.0470). NO2and NO mean concentrations in ambient air in the work enviroment were 0.0867 mg x m-3 (0.0165 to 0.1960) and 0.0614 mg x m-3 (0.0220 to 0.1090) respectively. For the determination of T-cell and (CD19+)B-cells populations Behring monoclonal antibodies were used in indirect immuno-fluores-cence tests. The serum levels of immunoglobulins: G, A, M, E; C3c and C4 complement components; total circulating immunological complexes (CIC) as well as acute phase proteins: C-reactive protein (CRP), haptoglobin, ceruloplasmin and transferrin were determined by nephelometry. Stimulation T-cell line in exposed to NO2 and NO was evidenced by in-creased number of (CD3+)T-cells, by about twice (p<0.001) increased number of (CD4+)T-helper cells and by increased number of (CD8+)T-suppressor cells. The higher increase in count of (CD4+)T-helper cells than (CD8+)T-suppressor cells population caused the increased value of the (CD+4)T-helper/(CD8+)T-suppressor ratio by about 25% (p<0.01) in the men exposed to NO2 and NO. No changes were observed in the number of (CD19+)B-cells as well as in the (CD3+)T/(CD8+)T-suppressor ratio. In men of exposed to NO2 and NO elevation of IgG serum concentration by a 17.7% (p<0.01) was evidenced as well as decreased of C3c by 18.6% (p<0.001) and C4 by 35% (p<0.001), whereas total CIC in serum was elevated by about twice (p<0.001). Significant positive correlations between concentrations of NO2 in air and numbers of total lymphocytes, (CD3+)-cells, (CD4+)T-helper, (CD8+)T-suppressor cells or IgG (/r/ from 0.31 to 0.71) as well as significant negative correlations between concentrations in air of NO2 and IgE, C3c, CRP or haptoglobin (/r/ from -0.49 to -0.31) were calculated. Moreover, significant positive correlation between NO concentrations in air in work place and counts of (CD3+)T-, (CD8+)T-suppressor, (CD19+)B-cells and levels in serum of C4, haptoglobin and ceruloplasmin (/r/ from 0.33 to 0.63) as well as significant negative correlations between NO concentrations in air in work place and serum levels of IgG, IgA and IgM (/r/ from -0.67 to -0.47) were also observed. In conclusion, environmental exposure to NO2 and NO can modificate in the peripheral blood of humans the parameters of cell-mediated and/or humoral immunity.
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Neighbours of intensive livestock production facilities frequently complain of odour annoyance. They are also concerned about potential negative health effects of environmental exposures to livestock emissions. Quality of life (QoL) was assessed in residents of a rural community neighbouring an area with high concentration of animal farms. A postal cross-sectional survey was carried out among the 4,537 residents, aged 18-44 years. Of these, 3,112 (69%) responded to questions on annoyance by livestock odours (4-point scale), on QoL (assessed by the short form 12, SF-12), and on potential confounders (age, gender, respiratory symptoms, smoking, living on or close to a farm, and employment status). SF-12 scores were available for 2745 (88%) subjects. Sixty-one percent of the respondents complained about unpleasant odours, 91% of these accused livestock as source of these odours. Physical and emotional SF-12 scores were inversely related to annoyance scores. Better risk communication might improve QoL in concerned neighbours of intensive livestock production facilities.
An explorative field study was conducted to assess residential exposure to pesticides, regularly applied in bulb farming. House dust floor samples were taken from homes of bulb farmers (n = 12) and from homes in close proximity to a bulb field (i.e. non-farmers) (n = 15). Samples were analysed for 7 pesticides used by bulb growers in the sampling period. Of these pesticides, chloropropham, flutolanil and vinchlozolin could be detected in non-farmers homes. All pesticides were detected in farmers' homes, except metamitron. Median concentrations for chloropropham were significantly higher in farmers' homes (0.05 vs. 0.20 µg/m2, p = 0.03). Logistic regression analyses showed that the odds for detecting pesticides were higher in farmers' compared to non-farmers' homes and remained higher after correction for potential confounders. Results showed no significant effect of proximity of a residence to a bulb field for median concentrations of pesticides; however, logistic regression analysis showed a borderline statistically significant effect for detecting chloropropham above the detection limit (OR = 10, p = 0.08). These findings demonstrate that, as expected, risk of exposure is higher for bulb farmers than for non-farmers. They also indicate that exposure to pesticides is not limited to bulb farmers only, and this warrants further investigation.
Despite legal regulations limiting emissions of persistent organic pollutants (POPs), including dioxins, to the environment, they still constitute a significant component of environmental contamination. They are released in large amounts during various processes of combustion in industry, the management of refuse materials and also as a result of situations that are partially beyond our control, like fires, explosions and damage in chemical industries. Observations originating from various studies prove that exposure to dioxins results in multiple toxic effects on humans and experimental animals. Among the various disorders caused by dioxins are abnormalities in dentition. The effects of dioxin may last long after exposure.
The objective of this study was to assess the relationship between lead, cadmium, zinc, and copper contents in the children's head hair and the level of environmental exposure in the subject's place of residence. The studied population was a group of 93 children (62 boys and 31 girls), aged 5-16, living in contaminated regions of the Copper Basin Legnica ("Exposed Group"). The control ("Reference Group") consisted of 66 children (35 boys and 31 girls), aged 6-16, inhabiting non - contaminated rural areas of the Wielkopolska region. The studied material was head hair taken from the occipital scalp. The contents of metals in the hair were determined using the atomic absorption spectrometry method. It was found that the mean contents of lead and cadmium in the hair were significantly higher in the "Exposed" children (7.16 mgPb/g and 0.44 mgCd/g) versus the "Reference Group" (2.49 mgPb/g and 0.23 mgCd/g). The mean contents of zinc and copper in the hair were not statistically different between the studied populations. Moreover, some positive and negative correlations between pairs of elements in the hair were found.
The aim of this study was to test a new method for the quantitative determination of metallo- thionein (MT), in order to determine the level of exposure to heavy metals. For MT preconcentration, the solid phase extraction (SPE) method with covalent affinity chromatography with thiol-disulphide interchange (CAC-TDI) gel was applied. In experiment Cd-thionein (Cd-Th) obtained from rats exposed to cadmium salt was used. Protein concentration was determined by indirect method based on metal analysis, bonded with MT protein by atomic absorption spectrometry (AAS). The results showed satisfactory correlation between Cd-Th concentration and the level of exposition for heavy metals.
Mercury is present in nature as metallic mercury, inorganic and organic compounds. Mercury levels constantly increase in the human natural environment. A similar rise of mercury content has been observed in human tissues. Kidney disease arising from exposure to heavy metals, mainly during occupational exposure to mercury, may play a special role in nephrology. Long-term exposure to mercury may cause progressive degenerative changes in the kidneys, possibly leading to renal insufficiency. The main renal changes caused by mercury are indicated by the both glomerular and tubular disfunction. Early renal damage may usually be monitored by measurements in urine excretion of very sensitive small proteins and of some enzymes. This article reviews data concerning the nephrotoxic effects of mercury compounds in animals and humans induced by exposure to mercury compounds with the results of our study in changes of proteins in urine excretion in groups of workers occupationally exposed to mercury vapours, (depending on degree and duration of exposure).
The aim of this study was to determine physiological and toxic metals in the teeth of inhabitants of Ruda Slaska and Bielsko-Biala - differently polluted areas - and to find out if environmental exposure to heavy metals has an influence on the occurrence and coexistence of these metals in teeth. The material consisted of 401 permanent teeth from inhabitants of these two cities. The contents of Cd, Cr, Cu, Fe, Mn, Pb, Zn, K, Na, Ca and Mg were determined by means of flame atomic absorption spectrometry. We concluded that environmental exposure to heavy metals has an influence on the occurrence and coexistence of these elements in teeth.
This review describes the structure, physicochemical properties and sources of asbestos as well as other mineral fibres in the natural environment. The diversity of character and methods for the determination of airborne inorganic fibres are discussed with particular attention to the biological effects on humans health. It also demonstrates the practical significance of asbestos.
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