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2021 ◽  
Vol 2 (5) ◽  
pp. 1-10
Author(s):  
Nanven D Nimyel ◽  
Elizabeth S. Chundusu

When the mining process is not properly controlled, it can be a source of heavy metals pollution in the environment. The uptake of these heavy metals in edible parts of vegetables can be a direct source of the metals into the human food chain. This study assessed the concentrations of lead (Pb), manganese (Mn), zinc (Zn), copper (Cu), nickel (Ni) and chromium (Cr) in soil and vegetables obtained from nine (9) farms around mining sites in Mangu LGA. Concentrations of heavy metals in soil and vegetables were determined using atomic absorption spectrophotometer (AAS). The results revealed the concentrations of the heavy metals at the farms to be within the recommended maximum levels of world soils but were higher than their respective controls. This implies that the artisanal mining contributed to the increased values of these heavy metals in the environment. Also, the mean concentrations of the heavy metals at Mangu Halle mining site decreased in the order Mn > Zn > Cr > Cu > Ni > Pb > Cd whereas at Alogwom it decreased in the order Mn > Zn > Pb > Cu > Ni > Cr > Cd. The enrichment factor (EF) of the elements showed deficiency to minimum enrichment for all the heavy metals whereas the pollution index (PI) of the metals indicated very slight contamination to moderate pollution. The results of the heavy metals in the vegetables showed that the bioaccumulation of the metals followed a pattern: Zn > Cu > Pb > Cr > Cd > Ni. Levels of Cd, Pb and Ni in the vegetables were observed to be higher than the recommended limit for vegetables whereas Cu, Cr and Zn exhibited lower values than recommended standards. Thus, their consumption might pose health risk to consumers and therefore there is the need for proper monitoring of the illegal mining activities to reduce health risk and the extent of heavy metals contamination.


2019 ◽  
pp. 2443-2456
Author(s):  
Murtadha J. Issa ◽  
Hussain Musa Hussain ◽  
Inas Hadi Shaker

     Brick factories distributed within the study area use fuel oil to complete the burning of the bricks, were high amounts of gases and suspended particles with different concentrations of heavy elements are produced and cause air and soil pollution. It is noted that the workers suffer from respiratory diseases and other health problems. This study is an attempt to detect the sources and concentrations of pollutants and to propose modalities for their treatment and reduction. Air and soil samples were collected from different sites in Abu Smeache brick factory in Al-Kifl area to the south of Babel city, Iraq, during two seasons (summer and winter). The process also included collecting and modelling of dust and soil samples from two depth, surface and sub-surface, to detect pollution and the mobility of heavy elements across the different depths. Heavy elements (Pb, Ni, Co), along with gases (CO, CO2, NO2, SO2) and total suspended particles (TSP) in the air, were analyzed by atomic absorption spectroscopy. The air results showed high pollution with all the studied heavy elements, while the levels of TSP and SO2 were higher than global and Iraqi limits in most of the studied stations, especially in the winter. The results also showed significant pollution in the soil with lead along with slight contamination with nickel and cobalt. Soil contamination was evaluated using several contamination indices; the values of contamination factors (CF) for the lead were very high, while CF values for nickel and copper indicated low to moderate pollution. Also, the high values of PLI ˃1 in the soil indicated high pollution with heavy elements, which provides clear evidence of the impact of industrial human activities on the environment of the region. In addition, low values of i-geo indicated a moderate contamination with lead and an unpolluted status for both nickel and copper. These results indicate a great need to develop strategies to prevent and reduce pollution by heavy metals in  the areas under rapid industrial and urban development.


2019 ◽  
Vol 2 (2) ◽  
pp. 46
Author(s):  
Victor Anozie Amadi ◽  
Harry Hariharan ◽  
Vanessa Matthew-Belmar ◽  
Roxanne Nicholas-Thomas ◽  
Claude DeAllie ◽  
...  

A study to determine the occurrence of Yersinia enterocolitica and Citrobacter freundii, two potential human pathogens in the throats of tropical pigs of Grenada origin and the antimicrobial pattern of the isolates was carried out. During a period of 30 days (15 September 2017 to 15 October 2017), throat swabs from a total of 97 weaned pigs were sampled to isolate and characterize Y. enterocolitica by serotyping and resistance testing, and to isolates C. freundii. Of the pigs tested, four (4.1%) pigs were positive for Y. enterocolitica. The four Yersinia-positive pigs included one (2.4%) of 41 male pigs and three (5.4%) of 56 female pigs. There were no significant differences between the proportions of Yersinia-positive male and female pigs (p = 0.8437). Of these four Yersinia-positive pigs, two were mixed with C. freundii, one had slight contamination, and the other was pure. All belonged to serotype 0:9.  There were 31 pigs positive for C. freundii, and all showed mixed growth. Antimicrobial susceptibility tests against 14 drugs indicated that all isolates of Y. enterocolitica were susceptible to third-generation cephalosporins and fluoroquinolones, two classes of antimicrobials recommended for the treatment of Y. enterocolitica infection in humans.


2019 ◽  
Vol 2 (2) ◽  
pp. p73 ◽  
Author(s):  
Henry Olawale SAWYERR ◽  
Morufu Olalekan RAIMI ◽  
Adedotun Timothy ADEOLU ◽  
Oluwaseun Emmanuel ODIPE

Soil pollution with Heavy Metals (HMs) has been of much interests lately and is one of the major issues to be faced globally and requires attention because heavy metals above their normal ranges are extremely threatened to both biotic and abiotic life. It was therefore of interest to conduct study to assess the extent of heavy-metal contamination of soils within battery technicians’ workshops within Ilorin metropolis, Kwara State, Nigeria. A total of twenty-five composite soil samples were collected from six selected battery charger workshop within Ilorin metropolis and analyzed for the presence of heavy metals using atomic absorption spectrophotometer. Result reveals significant positive relationship between Mn and Fe (r=0.511**, p<0.001), Mn and Cu (r=0.565**, p<0.001), Fe and Cr (r=0.895**, p<0.001), Fe and Cu (r=0.823**, p<0.001) and between Cr and Cu (r=830**, p<0.001). Result also shows significant negative relationship between Mn and Cr (r=-0.679**, p<0.001), Pb and Cu (r=-0.468*, p<0.05) respectively. The pollution status of heavy metals in soils was evaluated using quantitative indices (pollution index–PI). The result shows that Zn was moderately contaminated while other heavy metals (Pb, Cd, Cr and Cu) had very slight contamination (pollution index<0.1). The Ilorin metropolis soils of Kwara State were found to have a moderate to very slight contamination respectively. Large variations in PI values of Zn revealed that soil in those areas of the city, which are influenced by anthropogenic activities, have moderate concentrations of Zn resulting in “considerable risk”. The findings of this study recommend comprehensive continuous annual monitoring and auditing and further studies on the level of these heavy metals in the near future to ascertain long-term effects of anthropogenic impact is forestalled to protect the men and the environment. This should also involve larger coverage with studies on ground water around such locations. Furthermore, continuous metals speciation should be carried out so that the form and extent of metal bioavailability can be evaluated further.


2013 ◽  
Vol 39 (1) ◽  
pp. 77-82 ◽  
Author(s):  
M Amin Uddin ◽  
Minakshi Saha ◽  
MAZ Chowdhury ◽  
MA Rahman

Water samples collected from some selected ponds of Meherpur region were studied for the presence of organophosphorus and carbamate pesticide residues. High performance liquid chromatography (HPLC) technique was used to determine the concentration levels of those residues. The results obtained indicate slight contamination of some of the water samples with residues of diazinon, chlorpyriphos (organophosphorus insecticide) and carbofuran (carbamate insecticide). The residues level of diazinon and chlorpyriphos ranged from 0.033 to 0.079 ppm and 0.010 to 0.471 ppm respectively. Among carbamate pesticides, carbofuran identified in two samples ranged from 0.0143 to 0.0387 ppm, and carbaryl was not detected in any of the samples. Limit of detection (LOD) was 0.01 ppm. However, the residue level was also within the acceptable ranges according to the WHO guideline value of water quality. But, the presence of such residues is indicative of weak regulatory control which is required to be in place for safety of the environment and to stop further aggravation of the situation. J. Asiat. Soc. Bangladesh, Sci. 39(1): 77-82, June 2013 DOI: http://dx.doi.org/10.3329/jasbs.v39i1.16036


1996 ◽  
Vol 63 (1) ◽  
pp. 73-81 ◽  
Author(s):  
Christine Prin ◽  
Nezha El Bari ◽  
Paul Montagne ◽  
Marie-Louise Cuilliere ◽  
Marie-Christine Bene ◽  
...  

SummaryA microparticle-enhanced nephelometric immunoassay has been developed for the determination of caseinomacropeptide (CMP) in bovine milk. It is based on the nephelometric quantification of the competitive immunoagglutination of a microparticle–CMP conjugate with an anti-κ-casein (κ-CN) antiserum. This one step immunoassay was sensitive (detection limit in reaction mixture, 16μg/l), accurate (linear recovery of CMP in dilution overloading) and reproducible (CV 7–14% for within and between run precision). Because of the specificity of the polyclonal antiserum used, it was necessary to separate CMP from κ-CN by ultrafiltration before the quantification of bovine milk CMP. Under the conditions of milk ultrafiltration used, κ-CN was entirely retained (> 99·5%) but the concentration of CMP measured in milk ultrafiltrates was underestimated (by ∼25%) compared with its concentration in whole milk. Microparticle-enhanced nephelometric immunoassay of CMP, with a calibration range from 0·32 to 20 mg/1 for 20- fold diluted milk ultrafiltrate, allowed contamination of bovine milk by rennet whey as low as 5 ml/1 to be detected. Applied to ultrafiltrates from milk stored at 4 °C, this immunoassay also detected proteolysis of κ-CN not revealed by measurement of κ-CN concentration in milk. A statistical lower limit of 3·21 mg/1 was determined as the increase in CMP concentration in milk ultrafiltrates that indicated probable κ-CN proteolysis in the milk sample. Previously demonstrated to be an easy to perform method for assaying the main proteins of bovine milk, microparticle-enhanced nephelometric immunoassay thus also appeared to be appropriate to quantify CMP so as to detect slight contamination of milk by whey and to indicate the proteolysis of κ-CN during milk storage at low temperature.


1986 ◽  
Vol 64 (5) ◽  
pp. 448-455 ◽  
Author(s):  
Jacques Rembur ◽  
Pierre Landré ◽  
Arlette Nougarède

The validity of phase partition to obtain a substantial proportion of vesicles of plasmalemma origin from the microsomal fraction of pea epicotyl has been demonstrated. In the fractions enriched with plasma membranes, N-naphthyl phtalamic acid binding and β-glucan synthetase II activity, showed a yield of about 60% and an enrichment of 2.3 and 2.2, respectively, in comparison with the microsomal fraction. When such plasmalemmic vesicles are permabilized by Triton X-100, an intense Mg2+-ATPase activity is obtained in presence of K+ at acid as well as alkaline pH. Inhibition of Mg2+-ATPase by vanadate in presence of K+ and its variations in relation to pH were shown. Dicyclohexylcarbodiimide and diethylstilbestrol inhibit 40–55% of this enzymatic activity, both at acid and neutral pH. The data show a slight contamination of the plasmalemmic fraction by endomembranes and suggest an asymmetry of the two sides of the plasmalemma.


1986 ◽  
Vol 51 (7) ◽  
pp. 1411-1418 ◽  
Author(s):  
Pavel Karen ◽  
Bohumil Hájek

Contamination of reaction mixtures of rare earth elements and carbon by air oxygen and nitrogen at high temperatures results in changes in the phase composition of the products, which in turn lead to changes in the composition of the hydrolysis gas. La, Ce, Pr, and Nd give carbide-oxides Ln2O2C2 of acetylide nature, in concentrations increasing with increasing extent of contamination. For the smaller rare earth elements from Dy, Ho to Lu, the contamination leads to methanide-type carbide-oxides (or nitrides) M(C, N, O, ). A slight contamination of mixtures of the metals with carbon which are somewhat carbon-deficient with respect to the 1 : 2 composition gives rise to a phase which evolves a gas containing C3 hydrocarbons in a high concentration (nearly 50%), while its methane content is very low. The stability of this allylenide phase, which is not the M15C19 carbide, increases in the direction towards Lu to an extent such that the phase forms even besides higher amounts of the carbide-oxide-nitride, i.e., also on extensive contamination.


1978 ◽  
Vol 81 (3) ◽  
pp. 361-372 ◽  
Author(s):  
C. J. M. Rondle ◽  
B. Ramesh ◽  
J. B. Krahn ◽  
R. Sherriff

SummaryThis paper presents the hypothesis that some cases of cholera might be due to effluent discharge from aircraft. The theoretical case is borne out by inspection of data on the physical conditions pertaining between high altitudes and ground level. A study of the distribution of isolated outbreaks and single cases of disease and their relation to major airline routes showed a reasonable correspondence. Sporadic outbreaks of cholera in Europe between 1970 and 1975 were found to lie within the flight paths of regular airline services from Calcutta, where cholera is endemic, to the Northern Hemisphere. Laboratory studies on the stability of Vibrio cholerae to conditions likely to be encountered in droplets falling from high altitude to the ground suggested that significant numbers of organisms might survive. It should be noted that in this study no account was taken of the effect of ultra-violet light on viability and it is known that at high altitudes the ultraviolet light component of solar radiation is much higher than at ground level. Results of experiments where small numbers of organisms were inoculated into relatively poor media showed that rapid growth ensued and that sufficient organisms were produced to give an infective dose of Vibrio cholerae in 1–10 ml/fluid. It could be concluded that human infection could easily occur by ingestion of fluids such as milk or soup which had some time earlier received a fortuitous but slight contamination from the air. Investigation of one disinfectant (chloramine T) showed that it reacted rapidly and in a complex manner with peptone. One effect of this reaction was the elimination of bactericidal activity and it seems likely that, as at present employed, chloramine T is of doubtful value in aeroplanehygiene. One important conclusion that arises from this work is that if cholera can be spread, even only occasionally, by effluent from aircraft then close investigation should be made of the possibility of other bacteria and viruses being spread in a similar way.


1977 ◽  
Vol 40 (2) ◽  
pp. 109-111 ◽  
Author(s):  
BERNARD F. SURKIEWICZ ◽  
MARSHALL E. HARRIS ◽  
JERRY M. CAROSELLA

At the time of slicing and packaging, 179 of 180 retail-sized vacuum-packed sliced ham samples collected from 12 establishments had aerobic plate counts of 2,000 or fewer/g. Coliforms were isolated from only three of the samples, and all samples were negative for Escherichia coli, Staphylococcus aureus, and salmonellae. When stored at 3 C, bacterial growth in vacuum-packed, sliced ham proceeded at a rate similar to that of non-vacuum-packed, cross-sections cut from hams just before slicing. However, after 68 days of refrigerated storage, there was no bacterial growth in a non-vacuum-packed, cross-section cut from a ham removed from a can with strict aseptic techniques. These results suggest that the slight contamination upon opening canned hams by conventional methods may have as great an effect on the bacteriological stability of sliced ham as any additional slight contamination from the slicing-packaging operation.


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