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A Comparative Study of Organic Pollutants in Seawater, Sediments, and Oyster Tissues at Hab River Delta, Balochistan Coast, Pakistan
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Sadar Aslam, Malik Wajid Hussain Chan, Grzegorz Boczkaj, Ghazala Siddiqui
In both oyster samples, several PAHs were identified. The PAHS are present in petroleum fractions, and they are formed during thermal cracking taking place in some processes of crude oil processing (Gilgenast et al., 2011; Boczkaj et al., 2014; Makoś et al., 2018a, 2018b). This indicates a health risk for humans in this region because PAHs are carcinogenic. However, Gardner et al. (1991) has well documented the concentrations of organic contaminates in eastern oyster, Crassostrea virginica, and in sediments with reference to evidence scale as carcinogens. He gave a scale of carcinogens to different contaminants. According to his scale, Chrysene has limited evidence as carcinogens. Phenanthrene has inadequate evidence while anthracene and fluoranthene have no evidence of being carcinogenic. The only cancer promoter we detected in our results is pyrene. Bender et al. (1988) examined the distribution of PAHs in eastern oysters from the Elizbeth River, Virginia, and conducted laboratory studies compared the uptake and depuration of PAHs by eastern oysters and hard clam, Mercenaria mercenaria, with exposure to contaminated sediments from the Elizabeth River. Animals were exposed to contaminated sediments for 28 days, followed by a 28-day depuration phase. Oysters accumulated three to four times more total PAH than clams with similar uptake rates. Bioconcentration factors for oysters ranged from 1600 for phenanthrene to 36,000 for methyl-pyrene (Capuzzo, 1996).
Modeling Exposure
Published in Samuel C. Morris, Cancer Risk Assessment, 2020
The concentration of organic chemical in the nonvegetative portion of food crops was assumed to be 10% of that in the vegetative portion. Finally the bioconcentration factors in beef fat (Ff) and milk (Fm) relative to the concentrations in the animal’s feed were given as:
Benzene Metabolism (Toxicokinetics and the Molecular Aspects of Benzene Toxicity)
Published in Muzaffer Aksoy, Benzene Carcinogenicity, 2017
Keith R. Cooper, Robert Snyder
Benzene is ubiquitous in the environment and low level exposure occurs through water, natural food stuffs, and from atmospheric exposure. It has been estimated that 20 lb of benzene is lost per ton of benzene produced during transfer and storage of benzene, with approximately 94% lost as air emissions and 6% as water effluents.6 There is very limited data available on benzene present in water, but it has been detected in U.S. water supplies in the range of 0.1 to 0.3 ppb.7 The contamination of water supplies from gasoline also poses a risk for human exposure to benzene because benzene is blended into gasoline and is a natural component of petroleum products. Benzene is slightly soluble in fresh water, 0.8 parts by weight in 1000 parts of water at 20°C. Benzene has a relatively low-calculated bioconcentration factor of 1.3, based on benzene octanol/water partitioning.7 The absorption of benzene across the skin as a vapor or in aqueous media is minimal and is not therefore a major route for exposure. There are several reports in the literature on the occurrence of benzene in food stuffs.8,9 Benzene occurs naturally in fruits, fish, vegetables, nuts, dairy products, beans, and eggs. Eggs, for example, contain between 500 to 1900 μg/kg of benzene.
Geochemical speciation and bioaccumulation of trace elements in different tissues of pumpkin in the abandoned soils: Health hazard perspective in a developing country
Published in Toxin Reviews, 2022
Md Saiful Islam, Md Kawser Ahmed, Abubakr M. Idris, Khamphe Phoungthong, Md Ahosan Habib, Ramal Ahmed Mustafa
To establish a relationship between readily available form of essential and toxic elements in soil and its uptake by plants, it was necessary to determine the bioconcentration factor (BCF) and translocation factors (TF). Bioconcentration factor (BCF) of essential and toxic elements from soil to the edible parts of a plant was defined as the ratio of the element concentration in the plant’s tissues to the element concentration at exchangeable form in soil (Yoon et al.2006, Liu et al.2007, Islam et al.2018). Bioconcentration factor can be used to evaluate the plants capability to transfer the readily available elements from soil to the vegetative tissues and is one of the key components controlling metals exposure to human through food chain transfer. The BCF value of ≤1.00 is an indication that the plant can only take up elements but cannot accumulate in the tissues. BCF value >1.00 implies that the plant may have the ability to absorb and accumulate elements in their tissues (Liu et al.2007). BCF can be calculated using the relation in Equation (1): plant represent the concentration of essential and toxic elements (mg/kg dw) in the plant parts and Csoil represent the concentration of readily available essential and toxic elements (exchangeable form) in soil (Khan et al.2010, Islam et al.2018).
Trace elements concentration in soil and plant within the vicinity of abandoned tanning sites in Bangladesh: an integrated chemometric approach for health risk assessment
Published in Toxin Reviews, 2022
Md. Saiful Islam, Tapos Kormoker, Mohini Mazumder, Suraia Easnur Anika, Md. Towhidul Islam, Debolina Halder Hemy, Ummah Salma Mimi, Ram Proshad, Md. Humayun Kabir, Abubakr M. Idris
To establish a relationship between essential and toxic elements concentration in soil and its uptake by plants, it was necessary to determine the bioconcentration factor (BCF) and translocation factors (TF). Bioconcentration factor (BCF) of essential and toxic elements from soil to the edible parts of a plant was defined as the ratio of the element concentration in the plant’s tissues to the element concentration in soil. The BCF was calculated for each plant at each site separately. Bioconcentration factor can be used to evaluate the potential capability of plants to transfer elements from soil to the vegetative tissues and is one of the key components controlling human exposure to metals through the food chain. Bioconcentration factor (BCF) estimates the ratio of soil essential and toxic elements content to that in plant parts (Yoon et al. 2006, Liu et al. 2007, Islam et al. 2018b). The BCF value of ≤1.00 is an indication that the plant can only take up elements but cannot accumulate in the tissues. BCF value >1.00 implies that the plant may have the ability to absorb and accumulate elements in their tissues (Liu et al. 2007). BCF can be calculated using the relation in Equation (1): plant and Csoil represent the total essential and toxic elements concentration in the edible part of plant and metal concentration in soils on a dry weight basis, respectively (Khan et al. 2010, Li et al. 2012).
QSAR modeling, pharmacophore-based virtual screening, and ensemble docking insights into predicting potential epigallocatechin gallate (EGCG) analogs against epidermal growth factor receptor
Published in Journal of Receptors and Signal Transduction, 2019
Uma Devi Bommu, Kranthi Kumar Konidala, Neeraja Pabbaraju, Suneetha Yeguvapalli
CAESAR is a European Commission funded project specifically constructed in silico models to support the REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) legislation (www.caesar-project.eu/). This provides highly relevant five endpoints (bioconcentration factor, skin sensitization, carcinogenicity, mutagenicity and developmental toxicity) according to the OECD principles and US EPA standards. In this examination, the four endpoints, that is, mutagenicity, carcinogenicity, developmental toxicity and skin sensitization endpoints were investigated for data set compounds with CAESAR using VEGA-NIC v1.14 QSAR modeling package (https://www.vegahub.eu/). The datasets of 4204 (Ames test results), 806 (carcinogenic potency database compounds), 292 (Arena data set) and 209 (local lymph node assay model compounds) were used for regard toxicity endpoints investigation. The predictions are expressed in the form of binary as ‘toxic’ or ‘non-toxic’. Besides the prediction VEGA additionally provide applicability domain information for each endpoint. These criteria are defined as with three statements: prediction has low reliability (compound out of the AD), moderate reliability (compound could be out of the AD), and high reliability (compound into the AD). Furthermore, the model's performance was analyzed using AD space analysis and Cooper statistics by actualizing the 2 × 2 confusion matrix [19]; the accepted notions are discriminated as below:Sensitivity (True-positive rate) = TP/(TP + FN)Specificity (True-negative rate) = TN/(FP + TN)Precision or positive predictive value (PPV) = TP/(TP + FP)Negative predictive value (NPV) = TN/(TN + FN)Accuracy = (TP + TN)/(TP + TN + FP + FN)MCC = (TP × TN) – (FP × FN)/√(TP + FP)(TP + FN)(TN + FP)(TN + FN)where TP = True positive, TN = True negative, FP = False positive and FN = False negative.