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Laws, Regulations, and Risk Assessment Relevant to Site Assessment and Remediation
Published in Cristiane Q. Surbeck, Jeff Kuo, Site Assessment and Remediation for Environmental Engineers, 2021
Cristiane Q. Surbeck, Jeff Kuo
Environmental hazards can cause death and different types of diseases of the heart, liver, and nervous system. They may also cause genetic changes, including mutagenic, carcinogenic, and teratogenic. A mutagen is a physical or chemical agent that changes the genetic material of an organism so that the frequency of mutation would increase above the natural background level. Since many mutations can cause cancer, mutagens are likely to be carcinogens, but not necessarily so. Carcinogens cause cancer. Teratogens are agents that cause abnormalities in developing organisms in the womb. When a fetal abnormality is manifested, the infant could be born with a congenital defect, anomaly, or malformation.
Applied Chemistry and Physics
Published in Robert A. Burke, Applied Chemistry and Physics, 2020
Mutagens cause mutations or changes in genetic material. Changes may affect the current generation that was exposed or future generations. Examples include ethylene oxide and emissions from the combustion of crude glycerin and diesel fuel.
Fundamentals of Receptor Assessment
Published in Jack Daugherty, Assessment of Chemical Exposures, 2020
Mutagens cause mutations in the genetic code, altering the DNA of the exposed individual. Mutations may consist of chromosomal breaks, rearrangement of chromosome pieces, gain or loss of entire chromosomes, or changes within the gene structure. Table 10.8 lists known human mutagens.
Engineered Alcaligenes sp. by chemical mutagen produces thermostable and acido-alkalophilic endo-1,4-β-mannanases for improved industrial biocatalyst
Published in Preparative Biochemistry & Biotechnology, 2023
Oladipo Oladiti Olaniyi, Ademola Sunday Ajulo, Olusola Tosin Lawal, Victoria Kehinde Olatunji
Mutation by chemical mutagen is one of the traditional strategies, an affordable and acceptable way of improving microbial strains for enhanced industrial processes.[22] However, hosts of high-throughput methods referred to as genetic engineering have evolved and they ranged from recombinant technology to the recent one called CRISPR/Cas9 (clustered regularly inter-space palindromic repeats/CRISPR-protein associated 9).[16,24] The purpose of employing either traditional gene technology or genetic engineering is to obtain microbial strains with better traits for the production of desired products compared to the wild-type.[24] Interestingly, huge successes have been reported for both methods.[21–23] The present study is sought to employ a chemical mutagen for the improvement of wild-type Alcaligen sp-producing β-mannanase (being the first report from a bacterium). Future study may explore the genetic engineering method for wild-type bacterial gene improvement.
Phytocompounds from Anvillea radiata as promising anti-Covid-19 drugs: in silico studies and in vivo safety assessment
Published in Journal of Environmental Science and Health, Part A, 2021
Mourad Akdad, Soumia Moujane, Ismail Bouadid, Mohamed Benlyas, Mohamed Eddouks
The Lipinski’s rule of five (Ro5) of these molecules are presented in Table 3. The results of logP values and molecular weights of all designed compounds, indicating that they have reasonable absorption and are moderately soluble in water, were in excellent agreement with the most important rules of drug similarity. On the other hand the HBA of quercetin-3-glucoside, HBD of chlorogenic acid, the number of rotational bonds of neochlorogenic acid as well as cryptochlorogenic acid indicated that these four compounds did not respect the rules of lipnski (Table 3). The admetSAR online server also predicted four toxicological endpoints such as mutagenicity, carcinogenicity, hepatotoxicity, and LD50 value for acute toxicity in rats (Table 4). The AMES toxicity test is used to determine whether a compound is mutagenic or not. The results showed that all molecules were non-mutagenic, non-carcinogenic and non-hepatotoxic.
Development of a database on key characteristics of human carcinogens
Published in Journal of Toxicology and Environmental Health, Part B, 2019
Mustafa Al-Zoughool, Michael Bird, Jerry Rice, Robert A. Baan, Mélissa Billard, Nicholas Birkett, Daniel Krewski, Jan M Zielinski
Some of the key characteristics of carcinogens listed in Table 2 may be considered themselves as primary events that trigger conversion to malignancy. Some agents induce the initial mutagenic changes in stem and progenitor cells that start the cancer process. There are other key characteristics that may pertain to later stages of carcinogenesis such as (1) enhancing the growth, malignancy, or metastasis of already developed tumors through suppression of immune surveillance; and (2) hormone-mediated growth stimulation in the case of tumors derived from cells with appropriate receptors as in the case of estrogens. Epigenetic silencing of tumor-suppressor genes may occur in different phases during the various steps in cancer development (Hattis et al. 2009). These distinctions have important implications for cancer risk assessment, since agents that induce early changes in the development of cancer may be more clearly associated with cancer as an endpoint than those with characteristics associated with later stages.