A reusable macroporous polybenzoxazine resin with high specific surface area was prepared as sorbent material for the removal of mercury salts. For this purpose, allyl-functionalized bis-benzoxazine was cured in dimethyl sulfoxide by thermally activated ring-opening polymerization at 180 °C for 3 d followed by a freeze-drying process. The porous structure of the resin was confirmed by SEM analysis and N2 adsorption/desorption studies at 77.3 K. Among various metal ions, namely, Pb(II), Fe(II), Mn(II), Cu(II), Zn(II), and Cd(II), the porous polybenzoxazine resin exhibited a specific sorption behaviour towards Hg(II). Mainly chemisorption and to some extent adsorption mechanisms were proposed for the observed high loading capacity of the resin. As evidenced by FTIR spectral analysis, the chemisorption is attributed to the coordination system formed between free OH and tertiary amino groups in the polybenzoxazine structure and Hg(II) ions. It was also demonstrated that the porous polybenzoxazine can be regenerated simply by treatment with acids. The resin was recycled for up to seven cycles without any significant loss of activity, as proved by sorption and desorption experiments.
In this study, İstanbul-Tuzla Region atmosphere was selected as the working area for atmospheric pollution. Although the study area seems too local, this region contains shipyards and shipyard-related side product industries. It is also surrounded by aluminum (ASSAN) and copper (SARKUYSAN) facilities and tannery organized industrial district. For determined the atmospheric inputs, the sample collection was carried out as monthly in 2010. Particulate matter was filtered from aerosols via a high volume air sampler. The collected 46 ambient air samples were analyzed for Cr, Fe, Cu, Zn, Cd, Pb and Al using Atomic Absorption Spectrometry (AAS), Flame unit. Additionally, the volume of the air was drawn and meteorological data recorded.Average individual heavy metal concentrations were found as Cd (0.06 ng/m3) < Cr (0.09 ng/m3) < Zn (0.21 ng/m3) < Pb (0.23 ng/m3) < Cu (0.48 ng/m3). The concentrations of crustal elements Fe and Al were changed between 5.48 ng/m3, 74 ng/m3 and 14 ng/m3, 284 ng/m3 respectively during the sampling period. Except Cr and Fe anthropogenic contribution was seen on the concentrations of Zn, Cu, Pb and Cd in an increasing order. While the crustal element Fe was not show an appreciable change in concentration, but the Al concentration was display an important change in concentration depending on the wind transportation.
Prostate cancer is known to be affected by the heavy metal levels and oxidative damage of the body, yet there are very few studies which look into the way it occurs. The aim of this study was to determine whether blood and tissue lead (Pb), cadmium (Cd), and selenium (Se) levels are associated with oxidative damage in the context of prostate cancer progression and development. Seventy-nine patients comprising 25 patients with benign prostatic hypertrophy (BPH), 23 patients with malignant prostatic carcinoma (malign Ca), 16 patients with low-grade prostatic intraepithelial neoplasia (LGPIN), and 15 patients with high-grade prostatic intraepithelial neoplasia (HGPIN) diagnosed on the basis of their clinical profile, transrectal ultrasonography, and histopathology were included in this study. Cd and Pb levels in whole blood were found to be increased in patients with HGPIN compared with the BPH group; also, the levels of Cd in whole blood and tissue were found to be increasing in patients with malign Ca, unlike BPH patients. Moreover, the levels of malondialdehyde (MDA) in plasma and tissue were significantly increased in malign Ca, LGPIN, and HGPIN than those in BPH. However, the levels of tissue Pb were found to be decreasing in BPH, unlike the malign Ca and HGPIN patients, and the levels of tissue protein carbonyls in malign Ca were significantly lower than those in HGPIN. The levels of tissue reduced glutathione (GSH) in malign Ca were significantly lower than those in BPH. Additionally, the levels of Se in serum and tissue in LGPIN were significantly lower than those in BPH. The serum Se levels in HGPIN were also significantly lower than those in BPH and malign Ca groups. Furthermore, the concentrations of serum Se in LGPIN were significantly lower than those in malign Ca. From the Pearson correlation analysis, there were significant positive correlations between tissue Cd and MDA levels in malign Ca, LGPIN, and HGPIN and between the tissue Pb and tissue MDA and protein carbonyl levels in malign Ca. Blood Pb and tissue Pb were also significantly positively correlated with plasma MDA and protein carbonyl levels in malign Ca. In addition, blood Pb was significantly positively correlated with tissue MDA and protein carbonyl levels in malign Ca, and a significant positive correlation was also found between blood Cd and plasma protein carbonyls and tissue MDA in LGPIN. We observed that altered prooxidant-antioxidant balance and heavy metal levels may lead to an increase in oxidative damage and may consequently play an important role in prostate carcinogenesis. These findings indicate that changes in the levels of Pb, Cd, Se, MDA, protein carbonyls, and GSH in the blood and/or tissue are related to the prostatic carcinoma development and progression, although triggering one of the mentioned changes is unknown; therefore, further study is required to determine the exact steps of the process and clarify the roles of different substances in order to obtain a more detailed explanation of the phenomenon.
The aim of this study was to determine the total metal accumulation (aluminium, copper, manganese, lead, cadmium and iron) in different organs and eggs of Astacus leptodactylus (Eschscholtz, 1823) and sediments total metal contents (aluminium, copper, manganese, lead, cadmium, iron, zinc, chromium, nickel) in Lake Terkos. Water and sediment samples were collected from two stations at two different depths (1 and 2 m) of Lake Terkos in May 2008. Crayfish samples were collected by trammel net at the same region. Primary hydrographic conditions, such as temperature (13.6-19.4 degrees C), salinity (0.27-0.34 per thousand), dissolved oxygen (7.04-12.30 mg l(-1)) and pH (7.42-8.51), were recorded for each sampling point. Moreover, the total organic carbon (1.65-5.44%) and the total calcium carbonate contents (19.44-41.16%) of sediment samples were determined. According to the Turkish Food Codex (J Zool 26:283-288, 2002), the maximum allowable Pb and Cd levels in crayfish are 0.5 mg/kg wet weight. Accordingly, the Pb and Cd levels determined in A. leptodactylus samples are below this limit. However, when compared with the acceptable metal limits defined by WHO, Australian National Health and Medical Research Council and Ministry of Agriculture in United Kingdom (UK), it is clear that the Cu level is at the limit and the Cd results exceed the limit. When the metal contents in sediment samples from Lake Terkos are examined, it is seen that the Al, Fe, Mn, Ni and Cu contents are lower while Zn, Cr, Cd and Pb contents are higher than the crustal average values. The high values draw attention to the land-based domestic and industrial inputs. Lake Terkos sediments have high enrichment factors (EF) of Zn, Cr, Cd and Pb metals which corroborate this result. The low EFs of Fe, Ni and Cu are due to the natural (terrigeneous) inputs. Additionally, there is no Al, Fe, Ni and Cu metal enrichment in these lake sediments because of the low contamination factor (CF) values. However, it is moderately contaminated by Zn, Cr and Pb, and heavily contaminated by Cd.
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