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Objective:To observe the detrimental effect of airborne black carbon suspension solution of different concentrations on the tear film function of mice.Methods:Twenty-eight SPF-grade male BALB/c mice, aged 6-8 weeks, were randomly divided into four groups, 0.5 mg/ml group, 1 mg/ml group, 5 mg/ml group, and control group, with 7 mice in each group.The right eyes of mice were dropped by 4 μl of 0.5 mg/ml, 1 mg/ml, 5 mg/ml black carbon suspension, or phosphate buffer solution, 3 times a day according to grouping.Tear volume, tear break-up time (TBUT), corneal fluorescein staining (CFS), and conjunctival congestion were assessed before treatment and 4, 7, 10, and 14 days after treatment.The use and care of experimental animals complied with the Regulations for Administration of Laboratory Animals in Peking Union Medical College Hospital (No.XHDW-2022-053).Results:At 14 days after treatment, the tear volumes of 0.5 mg/ml group, 1 mg/ml group, 5 mg/ml group and control group were (2.74±0.74), (2.73±0.76), (2.31±0.67), and (5.31±0.36)mm, respectively.TBUT of the four groups were (4.87±0.28), (4.00±0.76), (3.23±0.43), and (6.22±0.22)seconds, respectively.CFS of the four groups were 4(3, 4), 5(5, 6), 7(7, 8) and 0(0, 1) points, respectively.Conjunctival congestion grades of the four groups were 2(2, 3), 2(2, 3), 3(2, 3) and 0(0, 1), respectively.There were statistically significant differences in tear volume among the four groups at different time points ( Fgroup=83.325, P<0.001; Ftime=86.551, P<0.001; Finteraction=5.181, P<0.001). Before and at each time point after treatment, tear volumes were significantly lower in 0.5 mg/ml group, 1 mg/ml group, and 5 mg/ml group than in control group, and tear volumes in 0.5 mg/ml group, 1 mg/ml group, and 5 mg/ml group were significantly lower at 4, 7, 10, and 14 days after treatment than before treatment (all at P<0.05). There were statistically significant differences in TBUT among the four groups at different time points ( Fgroup=75.130, P<0.001; Ftime=56.265, P<0.001; Finteraction=6.103, P<0.001). Before and at each time point after treatment, TBUT was significantly shorter in 0.5 mg/ml group, 1 mg/ml group, and 5 mg/ml group than in control group, and the TBUT was significantly shorter in 0.5 mg/ml group, 1 mg/ml group, and 5 mg/ml group at 4, 7, 10, and 14 days after treatment than before treatment, shorter in 1 mg/ml group and 5 mg/ml group at 14 days after treatment than 4, 7 and 10 days after treatment (all at P<0.05). There were statistically significant differences in CFS score and conjunctival congestion grades among the four groups at different time points, but the interactions between concentration group and measurement time were not statistically significant (CFS: Hgroup=59.249, P<0.001; Htime=49.959, P<0.001; Hinteraction=15.980, P=0.192.conjunctival congestion grade: Hgroup=57.622, P<0.001; Htime=42.062, P<0.001; Hinteraction=12.565, P=0.401). Before and at each time point after treatment, the CFS scores and conjunctival congestion grades were significantly higher in 0.5 mg/ml group, 1 mg/ml group, and 5 mg/ml group than in control group, and CFS scores and conjunctival congestion grades were significantly higher in 0.5 mg/ml group, 1 mg/ml group, and 5 mg/ml group at 4, 7, 10, and 14 days after treatment than before treatment (all at P<0.05). Conclusions:The exposure of airborne black carbon on the ocular surface causes damage to tear film function and ocular surface inflammation in BALB/c mice.Within a certain concentration and time range, the tear secretion decreases, TBUT shortens, CFS and conjunctival congestion increase.
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Background: Bacteria present in the atmosphere often show predicable patterns across space and time. and these patterns and properties of the bacteria can be affected by presence of soot which is generated by artisanal refining and excessive burning of fossil fuel. These bacteria are being inhaled by humans on daily basis and this can have detrimental effects on human health and the environment. Aim: This work was carried out to investigate the microbial load and antimicrobial susceptibility of an environment associated with artisanal refining activities. Methodology: The eight samples were taken randomly from four different locations in a high artisanal refining state Rivers State (Ojoto Roundabout, Nembe Waterside, Rumuokalagbor Village, Rivers State University Teaching Hospital (RSUTH), Rivers State University Microbiology laboratory and Mile 1 Park) all in Port Harcourt, Rivers State and compared to two locations from another state Kano state (No. 33 Lamido Crescent and God is Good Motors Park, Kano State) without artisanal refining activities all in Nigeria and tested for viable bacteria load. The six test and two control samples were collected on prepared dry nutrient agar exposed to free air for a period of five (5) minutes and were covered properly and transferred to the laboratory and incubated at 37OC for 24 hours. The isolates were morphologically and biochemically determined and identified. Results: The Total Heterotrophic count indicates that samples from Rumuokalagbor village have a high number of bacteria growth colonies with a colony forming unit of 1.43 x 106 while sample from Rivers State University Teaching Hospital had lesser colony forming unit of 7.5 x 105,. However, the Total Heterotrophic Bacteria Count from our control is seen to be very low with 3.2 x 105 and 2.8 x 105 respectively. Microorganisms such as Staphylococcus aureus, Bacillus species and Staphylococcus species. were identified from the various locations. Few isolates were gotten from the entire laboratory with a total of 22 isolates, 18 Bacillus species (77), 3 Staphylococcus species (18%) and 1 Staphylococcus aureus (5%). The antimicrobial sensitivity results revealed Ciprofloxacin (77%) having higher sensitivity followed by Levofloxacin (66.6%). Norfloxacin (0%), Rifampicin (0%) and Ampiclox (0%) were seen to be highly resistant to the bacteria isolated. Conclusion: This work was able to identify Bacillus species,Staphylococcus species and Staphylococcus aerues. as bacteria associated with artisanal refining at the different sampled sites. Strict implementation on stopping artisanal refining in our communities is recommended to reduce the public health risk posed by soot inhalation.
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Crude oil discovery and exploration in the Niger Delta of Nigeria which includes Delta, Bayelsa, Abia, Rivers, Cross River, Akwa-Ibom, Imo, Edo and Ondo States of Nigeria, has led to significant economic growth of the nation especially in the creation of job opportunities also the generation of revenue. Unfortunately, Oil thefts have become the idea that replaced the most crisis and agitations in the Niger Delta communities against the perceived neglect of the areas. This had resulted to widespread operation of illegal oil bunkering activities called Kpofire. Kpofire, as described by the Niger deltans, is a process of burning crude oil by illegal oil operatives or thieves at isolated locations called bunkering sites or dumpsites in order to extract refined petroleum products. The design for the extraction of the petroleum products involves the sections of steaming and collection. These sections are connected by a very long pipe. Heat is applied to the steaming section using wood from the mangroves that is called ‘Ngala’ or ‘Agala’, thereafter, crude oil is used. The products extracted are fuel, kerosene and diesel. One of the major problems of Kpofire is the introduction of soot into the environment. Soot is a product is uncontrolled and incomplete combustion or pyrolisis of materials that contain carbon. The highest constituent of soot is the Polynuclear aromatic hydrocarbon (PAH). The Niger Delta people are faced with daily environmental challenges such as inadequate housing facilities, contaminated drinking water sources, barren lands for agriculture, dead rivers for fishing activities and poor health conditions, soot, which has become a gradual but huge challenge in many Niger Delta communities, has been shown to play a huge role in respiratory, skin, and reproductive health conditions. However, vulnerability is seen more in babies and children (particularly because their respiratory organs are not matured enough), the elderly, and people with preexisting health conditions, also heart or lung diseases (such as asthma). High exposure to PAH at prenatal stages is linked to a low IQ and lead to increased behavioral problems in the early-age child and childhood asthma. A collective effort is needed to put a stop this menace called kpofire in order to avoid environmental pollution thereby endangering the health of the people of Niger Delta.
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Background: Soot is a by-product of incomplete combustion of carbon derived from substances that contains carbon like hydrocarbons, which is associated with various human diseases. The objectives of the studies are to evaluate the toxicological effects of prolonged exposure of soot polluted air on some haematological and biochemical parameters.Methods: One hundred apparently healthy residents of Port Harcourt residing in soot polluted environment for a minimum of 12 months and one hundred apparently healthy subjects residing in non-soot polluted environment outside Port Harcourt were recruited for this study. 5ml of venous blood was collected from each subject after 10hours of overnight fast to estimate the PCV, Hb, RBC, WBC, lymphocytes, neutrophils, bicarbonate, total cholesterol, triglyceride, low density lipoprotein and high density lipoprotein using automated autoanalyzer.Results: There was a statistically significant decrease in the PCV, Hb, RBC and increase in WBC, Lymphocytes and neutrophils. There was also a significant increase in the bicarbonate, total cholesterol and LDL with a decrease in HDL cholesterol as compared to the control.Conclusions: It is concluded that prolong exposure to soot polluted air is harmful and associated with deterioration of haematological parameters and also induces oxidative stress and lipid peroxidation which may increase morbidity and mortality.
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Objective:To make an assessment on the genotoxicity caused by black carbon ( BC ) and ozonized black carbon (O3-BC).Methods: In this study, 74 healthy male ICR mice [weighed (28 ± 1.5) g] were randomly divided into 7 groups, including one phosphate buffer solution ( PBS) control group and six particles exposed groups by intratracheal instillation with either BC or O 3-BC at the doses of 50, 100, 200 μg/mouse, respectively.There were 12 mice in the groups of 200μg/mouse and 10 mice in others.The mice were sacrificed 24 h after four intratrachealinstillations .The activities of catalase ( CAT) in serum and the levels of malondialdehyde ( MDA) in lung tissue homogenate were measured . As the DNA damage mark , 8-hydroxyguanosine ( 8-OHdG ) in urine and serum were quantified with ELISA method.Micronucleus test was used for potential genotoxicity of BC and O 3-BC.Hematoxylin and eosin staining was used to stain lung paraffin section .Results:The mice were in good condition during instillation , and the liver coefficient of the test groups was significantly lower than that of the control group (P<0.05).The activities of CAT in serum significantly increased in the 100 μg/mouse and 200μg/mouse groups after being exposed to these two kinds of particles .The micronucleus rate in allthe BC and O3-BC exposed groups increased ( P <0.05), but there was no statistically significant difference among the groups in the levels of 8-OHdG in serum and urine and MDA in lung tissue homogenate .In-flammatory response was found in the lung tissue under the microscope after exposure to BC and O 3-BC. Conclusion:Intratracheal instillation of BC and O 3-BC induced increasing of oxidative stress and genetic damage in mice .But there was no significant difference between these two particles in toxicity .Whether the genotoxicity of O 3-BC is higher than that of BC or not is uncertain .Further research is needed .
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The protection of our environment is a common task. All pollution that expose our soils, plants or in the narrower and wider sense environment will appear sooner or later in the food chain and in human beings who are at the top of the food-chain pyramid. The aim of our work is to give a brief overview about the effects of some industrial wastes on the physiological parameters of plants. Compost, black soot, sewage sludge and lime sludge dust was examined. Sunflower seeds were used in the experiments. The filtrates of examined materials were added to the nutrient solution in different quantities because of different solubility.The contents of sample elements and uptake of the element were measured by ICP, the relative chlorophyll contents by SPAD 502. Disadvantageous and advantageous physiological effects of compost, black soot, sewage sludge and lime sludge were proved. Larger concentrations of aluminium were measured in the roots than in the shoots. The concentrations of chrome were below the control value in the shoots when black soot, compost, lime sludge and sewage sludge were added to the nutrient solution. The concentrations of zinc, phosphorous, magnesium and copper were very low when black soot was used, and it was lower than the control. The dry matter of shoots increased when compost and sewage sludge was used, but the growth of roots remained under the control level.
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ve To study the way of oxidative stress induced by soot rat pulmonary cells type Ⅱ ?Methods Before exposure to soot extracts, the rat pulmonary cells were pretreated with anti-oxidative agent, N-acetylcysteine (NAC), vitamin C, vitamin E and mannitol for 30 minutes, then the ceils were exposed to the soot extracts for 24 hours. MTT assay was applied to detect the cytotoxicity. Results It showed that NAC, vitamin C and vitamin E could reduce the cytotoxicity of rat pulmonary cell caused by soot, but no same change was observed in that of man-nitol. Conclusion It was suggested that the DNA oxidative stress of soot may be caused by multi-ways, such as in-duction of oxygen free radical and lipid peroxide etc.