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Influences of binding to dissolved organic matter on hydrophobic organic compounds in a multi-contaminant system: Coefficients, mechanisms and ecological risks
2015
Li, Yi-Long | He, Wei | Liu, Wen-Xiu | Kong, Xiang-Zhen | Yang, Bin | Yang, Chen | Xu, Fu-Liu
The complexation flocculation (CF) method was successfully employed to identify binding coefficients (Kdoc) of specific organic contaminants to dissolved organic matter (DOM, often indicated by dissolved organic carbon, DOC) in a multi-contaminant hydrophobic organic contaminant (HOC) system. Kdoc values were obtained for most of the evaluated 33 HOCs, indicating the feasibility and applicability of the CF method in a multi-contaminant system. Significant positive correlations were observed between binding coefficients and octanol–water partition coefficients (Kow) for organic halogen compounds, such as polybrominated diphenyl ethers (PBDEs) (R2 = 0.95, p < 0.05) and organic chlorine pesticides (OCPs) (methoxychlor excluded, R2 = 0.82, p < 0.05). The positive correlations identified between the lgKdoc and lgBCF (bioconcentration factor) for PBDEs and OCPs, as well as the negative correlation observed for polycyclic aromatic hydrocarbons (PAHs), indicated that different binding or partition mechanisms between PAHs and organic halogen compounds exist. These differences further result in discriminative competition partitions of HOCs between DOM and organisms. Assuming that only freely dissolved HOCs are bioconcentrative, the results of DOM-influenced bioconcentration factor (BCFDOM) and DOM-influenced lowest observed effect level (LOELDOM) indicate that the ecological risk of HOCs is decreased by DOM.
اظهر المزيد [+] اقل [-]Levels of persistent organic pollutants in pine tree components and ambient air
2020
Cindoruk, S Sıddık | Sakin, A Egemen | Tasdemir, Yücel
Pine needles are employed as alternative biomonitoring agents in atmospheric studies. In this study, pine (Pinus Pinea) components (needles and branches) and air samples were collected simultaneously to monitor polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) from Gemlik, Turkey between January and December 2016. The relationship between ambient air and pine needles were examined to enlighten the usability of pine components as passive samplers for persistent organic pollutants (POPs) in the Marmara region. Average ∑14PAH concentrations for the ambient air, pine needles, and pine branches were 23.1 ± 18.3 ng/m3, 626 ± 306 ng/g DW and 548 ± 261 ng/g DW respectively. PCB concentrations were 118 ± 74 pg/m3, 7.5 ± 2.1 ng/g DW and 6.8 ± 2.9 ng/g DW and ∑10 OCP concentrations were 122 ± 89 ng/m3,1.3 ± 1.5 ng/g DW and 10.0 ± 3.8 ng/g DW in the same order. Levels of PAHs and PCBs were higher in needles than branches. PAH, PCB and OCP concentrations in pine components tended to decrease with increasing temperatures in spring. PAH compounds with medium and light molecular weighted ones were found to be dominant. On the other hand, the predominant PCB components were the medium-weighted congeners while γ-HCH, Heptachlor endo. Epox. Iso A, endrin aldehyde, and methoxychlor were the dominant OCP species.
اظهر المزيد [+] اقل [-]Association of in utero exposure to organochlorine pesticides with thyroid hormone levels in cord blood of newborns
2017
Luo, Dan | Pu, Yabing | Tian, Haoyuan | Wu, Weixiang | Sun, Xin | Zhou, Tingting | Tao, Yun | Yuan, Jing | Shen, Xiaoli | Feng, Yaqian | Mei, Surong
Organochlorine pesticides (OCPs) had been widely used in agriculture and disease prevention from the 1940s–1960s. Currently, OCPs are raising global concerns due to their associated prevalent contamination and adverse health effects, such as endocrine disruption. Several epidemiological studies have explored the underlying association of OCPs on thyroid hormone (TH) status in adults and newborns, but the results of studies performed on newborns are often inconclusive. This exploratory study was conducted with the purpose of assessing the potential association of the prenatal exposure to OCPs with the concentrations of TH in the cord blood of newborns from China. Cord blood and information on demographic characteristics were collected from 115 newborns between November 2013 and June 2014. The exposure levels of 17 OCPs were measured with a gas chromatography/mass spectrometry, and TH levels including free triiodothyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH) were detected using electrochemiluminescence immunoassay methods. After adjusting for confounding factors (the age of pregnant mothers, education level, monthly household income, parity, and sex of the newborns), we found marginally significant inverse associations of cord plasma measurements of ∑hexachlorcyclohexanes (∑HCHs), 1,1-dichloro-2,2-di(4-chlorophenyl)ethylene (ρ,ρ′-DDE) and methoxychlor with FT4 levels, but not with FT3 and TSH levels. Moreover, higher cord plasma levels of aldrin, dieldrin, ∑dichlorodiphenyltrichloroethanes (∑DDTs), ∑Drins, and ∑OCPs were found to be related to the increase in cord plasma TSH levels after the adjustment for confounders. The results of this exploratory study indicate that in utero exposure to certain OCPs may affect TH status in newborns, and therefore, pose potential effects on early human development. Further research, with larger sample sizes, should be conducted to confirm these findings.
اظهر المزيد [+] اقل [-]Organochlorine pesticides in follicular fluid of women undergoing assisted reproductive technologies from central China
2015
Zhu, Yindi | Huang, Bo | Li, Qing X. | Wang, Jun
Female infertility rates have increased by approximately 4% since the 1980s. There is evidence of adverse effects on female fertility in relation to exposure of chemical pollution in recent years. Follicular fluid samples were collected from 127 woman patients (aged 20–35) who underwent assisted reproductive technologies (ART) and had no records indicating occupational exposure to OCPs. Seventeen OCPs were analyzed in this study. The results showed that methoxychlor was dominant, accounted for 13.4% of total OCPs with a mean concentration of 167.9 ± 33.9 ng/g lipid weight (lw), followed by heptachlor-epoxide, hexachlorocyclohexanes, endrin and DDT. The concentrations of OCPs in the follicular fluid samples in the present study were moderate in comparison with those reported from developed or industrialized countries. All these pollutants can accumulate in different tissues of human body through diet, drinking water and respiration. No correlation between patient age and OCP concentrations was observed in this study.
اظهر المزيد [+] اقل [-]Baseline occurrence, distribution and sources of PAHs, TPH, and OCPs in surface sediments in Gorgan Bay, Iran
2022
Zafarani, Ghasem Ghorbanzadeh | Karbalaei, Samaneh | Golshani, Reza | Pustokhina, Inna | Walker, Tony R.
Baseline polycyclic aromatic hydrocarbons (PAHs), total petroleum hydrocarbons (TPH) and organochlorine pesticides (OCPs) in surface sediments were measured in Gorgan Bay, Iran. Total PAHs, TPH, and OCPs concentrations ranged between 13.70 and 23.68 ng g⁻¹, 2.97 to 11.51 μg g⁻¹ dry weight, and below detection to 1.41 ng g⁻¹, respectively. Benzo [k] fluoranthene and anthracene had the highest (BkF; 19.77 ± 0.08 ng g⁻¹), and lowest (Ant; 4.38 ± 1.72 ng g⁻¹) individual PAH concentrations, respectively. The most abundant OCPs were β-Endosulfan, followed by methoxychlor and endrin. PAH isomeric ratios in sediments revealed that contamination originated from mixed sources, with a strong indication of pyrogenic sources. Ecological risk assessments based on sediment quality guidelines (SQGs) suggested that individual PAHs and OCPs posed low ecological risks in Gorgan Bay.
اظهر المزيد [+] اقل [-]Risk assessment of organochlorine pesticides in seaweeds along the Gulf of Mannar, Southeast India
2020
Sundhar, S. | Shakila, Robinson Jeya | Jeyasekaran, Geevaretnam | Aanand, S. | Shalini, R. | Arisekar, U. | Surya, T. | Malini, N Asha Hema | Boda, Sathyanarayana
Bioaccumulation of organochlorine pesticides (OCPs) in red, green, and brown seaweeds from the Gulf of Mannar was investigated using gas chromatography–mass spectrometry (GC–MS). The concentration of OCPs in all the seaweeds was in the order of endosulfan > endrin > HCH > DDT > aldrin > heptachlor > methoxychlor. The concentrations of HCH, endrin, endosulfan, and DDT in Sargassum wightii and Gelidiella acerosa, and HCH and endosulfan in Gracilaria verrucosa were above the limits prescribed by the European Commission. However, in Ulva lactuca, except for endosulfan, all other OCPs were below the permissible level. The bioaccumulation of OCPs in seaweeds was in the order of S. wightii > G. acerosa > Gracilaria verrucosa > U. lactuca. The results of comparative analysis of the levels of the investigated pesticides against the standard human health risk assessment revealed that pesticide exposure from seaweeds is hazardous to human health and the marine environment of the Gulf of Mannar.
اظهر المزيد [+] اقل [-]DLLME-SFO-GC-MS procedure for the determination of 10 organochlorine pesticides in water and remediation using magnetite nanoparticles
2020
Carvalho, Rhiane Ramos Rocha | Rodriguez, Mariandry Dela Valle Rodriguez | Franco, Elton Santos | Beltrame, Felipe | Pereira, Alex Leite | Santos, Vívian Silva | Araujo, Wildo | Rocha, Bruno Alves | Rodrigues, Jairo Lisboa
There exists a high demand for fast, simple, and reliable methodologies for determining the presence of organochlorine pesticides (OCPs) on environmental samples. Moreover, the toxicity and accumulation of potential OCPs in several environments have led to the development of technologies that achieve their removal from contaminated waters. In this study, a novel method combining a dispersive liquid–liquid microextraction procedure based on the solidification of floating organic drop is developed and validated for the extraction, preconcentration, and determination of 10 OCPs: α-BHC, p,p′-DDE, δ-BHC, dieldrin, p,p′-DDT, endosulfan I, endosulfan sulfate, heptachlor, heptachlor epoxide (isomer B), and methoxychlor in water samples. The results show that the calibration curves were linear for all the studied compounds, and the coefficients of correlation higher than 0.99. The variation coefficient for precision and accuracy was lower than 10%, and the accuracy ranged from 93 to 105%. Low limit of detection and limit of quantification values ranging from 0.06–3.00 ng mL⁻¹ and 0.20–10 ng mL⁻¹ were obtained, respectively. The capability of the proposed method was confirmed using an analysis of the water samples before and after the degradation process; this was achieved by employing nanomaterials, while performing an analysis of 160 real samples that were sourced from a Brazilian river. A cobalt-doped magnetite was applied for the environmental remediation of the studied compounds, and it was verified that the novel material has the potential to be used in environmental remediation with a degradation efficiency exceeding 80% for the majority of the studied compounds.
اظهر المزيد [+] اقل [-]Multi-residue analysis of fifty pesticides in river waters and in wastewaters
2021
Paíga, Paula | Sousa, Sara | Vera, José | Bitencourt, Luciana | Vieira, Joana | Jorge, Sandra | Silva, Jaime Gabriel | Correia, Manuela | Domingues, Valentina F. | Delerue-Matos, Cristina
Three sampling campaigns were performed in the Lis River (Leiria, Portugal) in February of 2018, November of 2018, and May of 2019. River water and wastewater (influent and effluent) samples of two wastewater treatment plants were target of the study. A total of 25 samples were collected and 50 pesticides were monitored, including organochlorines, triazines, pyrethroids, and organophosphorus, among others. Most of the detected pesticides were insecticides and mainly organochlorines. Concentrations between 1.29 and 2134 ng/L were found. Aldrin, γ-HCH, and cypermethrin were detected in some samples in μg/L, being γ-HCH the pesticide most frequently detected with concentration in μg/L level. The pesticides with the highest detection frequency were (i) cypermethrin, HCB, methoxychlor, and ζ-HCH in river waters; (ii) isoproturon, cypermethrin, methoxychlor, pyrimethanil, γ-HCH, dieldrin, diuron, α-HCH, and α-endosulfan in effluents; and (iii) diuron and isoproturon in influents. The detection of the organochlorides and their degradation products is a consequence of their persistence in the environment, as their usage has long been prohibited in the European Union. Pesticides were grouped by their types in herbicides, insecticides, or fungicides and the detection and concentration for each type were discussed with the climatic conditions. Pesticide toxicity index was determined in the samples collected in the river.
اظهر المزيد [+] اقل [-]Occurrence, distribution, and risk of organochlorine pesticides in food and greenness assessment of method
2021
Adeyi, Adebola Abosede | Babalola, Babafemi | Akpotu, Samson Oghenemauro
Organochlorine pesticides (OCPs) have been used globally to boost food production. Although banned, due to their prolonged toxic effects but their residue still impacts the quality of primary and processed agricultural products. This study assesses the levels of residual OCPs (α,β,δ-HCH, heptachlor, heptachlor epoxide, chlordane, methoxychlor, aldrin, dieldrin, endrin, endrin aldehyde, endrin ketone, endosulfan, endosulfan sulfate, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), and 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT)) in food commonly consumed in Lagos and Ibadan, Southwest, Nigeria. Health risk associated with human exposure via food intake was evaluated with a statistical predictive model. About 248 composite food samples from 8 categories were analyzed in Lagos and Ibadan. Sample extraction and clean-up were by QueChERS method and extracts injected into GC-μECD. ƩDDT concentration was highest in meat products, aquatic foods, dairy products, edible oils, fruits, and cereals, while ƩHCHs were highest in chicken eggs and vegetables. ƩOCP concentrations (ng/g) in food categories were 6.09±1.6–6.85±0.9 (meat), 5.29±2.0–12.3±14 (aquatic foods), 4.86±1.7–5.89±0.8 (dairy products), 4.53±0.8–6.32±1.1 (edible oils), 3.32±1.3 (eggs), 3.54±1.0–4.80±1.5 (fruits), 4.16±2.7–4.40±0.8 (vegetables), and 6.12±2.0–6.62±0.9 (cereals). The estimated average daily intake of OCPs was 5.91, 12.5, 4.41, 6.40, 1.53, 5.14, 3.95, and 16.7 ng/kg bw/day through the consumption of meat products, aquatic foods, dairy products, edible oils, chicken eggs, fruits, vegetables, and cereals, respectively. The health risk of residual OCPs via ingestion of foods considered in this study was <1, which implied no potential health risk at the current consumption rate. However, regular monitoring of OCPs residues in food is highly recommended. Finally, the method scaled the analytical Eco-Scale evaluation and Green Analytical Chemical Procedure Index as “an acceptable green analysis method.”
اظهر المزيد [+] اقل [-]Mercury and Chlorinated Pesticides on the Highest Level of the Food Web as Exemplified by Herring from the Southern Baltic and African Penguins from the Zoo
2013
Falkowska, Lucyna | Reindl, Andrzej R. | Szumiło, Emilia | Kwaśniak, Justyna | Staniszewska, Marta | Bełdowska, Magdalena | Lewandowska, Anita | Krause, Izabela
Aquatic birds are often used as a health indicator of the marine ecosystem. African penguins living in the zoo make good research material as they form a link between the marine and the terrestrial ecosystem in terms of xenobiotic circulation. Tests were performed on whole herring—the food of the penguins—as well as on bird muscle, liver, brain, eggs, feathers and guano in order to determine total mercury, aldrin, dieldrin, endrin, isodrin, endosulfan isomers, endosulfan sulfate, methoxychlor, dichlorodiphenyltrichloroethane (DDT) and its metabolites. In herring and penguin, the tests did not show the presence of β-endosulfan, endosulfan sulfate, aldrin and isodrin. It was shown that penguins absorb about 36.8 μg of organochlorine pesticides and 4.6 μg of mercury with their food on a daily basis. Xenobiotics accumulate mostly in the liver, from where they are transported to the muscles and the brain, where the highest bioaccumulation factor is reached by endrin and pp’-DDT. Conceivably, the older the penguin, the higher is the concentration level of pesticides in its liver and brain. Molting was found to be the most effective way of eliminating mercury, dieldrin and methoxychlor from the system. Insecticides, such as DDT and its metabolites, were removed most effectively by females through laying of eggs. The standard four eggs laid within a year may have contained up to 20 % of the total amount of pesticides which had been absorbed with food, but no more than 5 % of mercury.
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