Degradation of Azo Dyes with Different Functional Groups in Simulated Wastewater by Electrocoagulation

Increasing attention has been paid to the widespread contamination of azo dyes in water bodies globally. These chemicals can present high toxicity, possibly causing severe irritation of the respiratory tract and even carcinogenic effects. The present study focuses on the periodically reverse electrocoagulation (PREC) treatment of two typical azo dyes with different functional groups, involving methyl orange (MO) and alizarin yellow (AY), using Fe-Fe electrodes. Based upon the comparative analysis of three main parameters, including current intensity, pH, and electrolyte, the optimal color removal rates for MO and AY could be achieved at a rate of up to 98.7% and 98.6%, respectively, when the current intensity is set to 0.6 A, the pH is set at 6.0, and the electrolyte is selected as NaCl. An accurate predicted method of response surface methodology (RSM) was established to optimize the PREC process involving the three parameters above. The reaction time was the main influence for both azo dyes, while the condition of PREC treatment for AY simulated wastewater was time-saving and energy conserving. According to the further UV–Vis spectrophotometry analysis throughout the procedure of the PREC process, the removal efficiency for AY was better than that of MO, potentially because hydroxyl groups might donate electrons to iron flocs or electrolyze out hydroxyl free radicals. The present study revealed that the functional groups might pose a vital influence on the removal efficiencies of the PREC treatment for those two azo dyes.

Encapsulation of Flavonoids in Nanocarriers

The term “flavonoid” is a broad term given to the collection of natural polyphenolic compounds which occur in plants (fruits, vegetables, roots, flowers, stems, bark, leaves) as their secondary metabolites. Subsequent research reveals that flavonoids possess anti-inflammatory, anti-mutagenic, anti-oxidative, anti-ageing, and anti-carcinogenic effects along with their capacity to modulate enzymatic activities, inhibit cell proliferation, and inhibit bacterial growth, among others. The main shortcomings of oral administration of flavonoids as therapeutic that various studies have revealed are related to their stability, bioefficacy, and bioavailability. Novel nanotechnological strategies involving nanocarrier systems are proving promising to overcome the delivery challenge of flavonoids as therapeutics. Nanocapsules, nanospheres, solid lipid nanoparticles, nanoemulsions, micelles are examples of novel nanocarrier systems that are currently being explored for targeted and efficient bio functioning of flavonoids after their oral administration.

The Carcinogenic Effects of Formaldehyde Occupational Exposure: A Systematic Review

Background: Formaldehyde, classified as a carcinogen in 2004, as of today is widely used in many work activities. From its classification, further studies were performed to evaluate its carcinogenicity. The aim of the systematic review is to update the evidence on occupational exposure to formaldehyde and cancer onset. Methods: The review, in accordance with the PRISMA statement, includes articles in English reporting original results of studies conducted on workers exposed to formaldehyde, considering all types of cancer, published from 1 January 2000 to 30 July 2021 and selected from the Pubmed and Scopus databases. The studies’ quality was assessed by the Newcastle–Ottawa Scale. Results: A total of 21 articles were included, conducted in different European, American, and Asian countries. The most investigated occupational areas are those characterized by a deliberate use of formaldehyde. Some studies evaluated all types of cancer, whereas others focused on specific sites such as thyroid and respiratory, lymphohematopoietic, or central nervous systems. The results showed weak associations with lung cancer, nasopharyngeal cancer, leukemia, and non-Hodgkin’s lymphoma. Conclusions: The results demonstrate the need for further original studies carried out on representative samples of workers exposed to measured levels of FA. These studies should be designed to reduce the bias due to co-exposure to other carcinogens.

REMOVAL OF BERYLLIUM (Be2+) FROM WATER SAMPLES BY SORPTION PROCESS: A REVIEW

Beryllium (Be2+) is an important industrial metal because of its unusual material properties: it is lighter than aluminium and six times stronger than steel. Beryllium is a strategic metal due to its low density combined with its strength, low neutron absorption, high melting point and high modulus of elasticity. Beryllium is often alloyed with other metals such as copper and is an important component of materials used in the aerospace, automotive, energy, defense, medical, and electronics industries. However, beryllium and its compounds are very toxic, especially to the lungs, skin, and eyes. Beryllium compounds are known carcinogens based on sufficient evidence of carcinogenicity in humans from human studies. Toxic effects of beryllium include immunotoxic, allergic, mutagenic, and carcinogenic effects. Mammalian tissues do not excrete it, so the effects are cumulative and can lead to death at high concentrations. Therefore, removal of Be2+ is important. In this review, the removal of Be2+ from water samples by sorption processes using different sorbents was summarized. The effects of process parameters on the removal of Be2+ have been summarized. The work discussed showed that ion exchange resins, various modified biosorbents metal oxides can be used for the removal of Be2+. The results showed that the pH of the solution has an important effect on the removal rate. Sorption kinetics vary from 3 minutes to 48h. When the functional groups are on the surface of the sorbent, the sorption process is rapid. However, if the surface of the sorbent is covered with oxides such as magnetite, it takes longer to reach equilibrium. Published work shows that more than 99 % of Be2+ can be removed from solution.

Evaluation of Carcinogenic Polyaromatic Hydrocarbon Levels in Airborne Particulates Associated with Long-Term Exposure throughout the COVID-19 Pandemic in Makkah, Saudi Arabia

Background: The effect of polyaromatic hydrocarbons (PAHs) on human health differs depending on the duration and exposure path. Objective: This study aimed to examine the effects of PAHs on the human health risks associated with long-term exposure both before and throughout the COVID-19 pandemic. Methodology: PM10 sampling for 24 h was conducted at six sampling sites (Al-Haram, Aziziyah, Al Nuzhah, Muzdalifah, Arafat, and Al Awali). On-site measurements were conducted from March 2020 to February 2021. PAHs were analyzed using Perkin Elmer GC/MS, which was adjusted with standard reagents for identifying 16 PAH mixtures. Results: The 24 h average PM10 concentration showed considerable inconsistencies, exceeding the WHO standards used for median exposure (25.0 µgm−3). The PAH intensities fluctuated from 7.67 to 34.7 ng/m3 in a suburban area, near a rush-hour traffic road, and from 6.34 to 37.4 ng/m3 close to business and light manufacturing areas. The highest carcinogenic compound levels were found in the Al-Azizia, Al Muzdalifah, and Al Nuzah areas because of the high traffic density, and the lowest concentrations were found in the Al-Haram and Arafat areas throughout the year, as a result of the COVID-19 pandemic health precautions that were undertaken by the government of Saudi Arabia involving border entry limits and limitations of the Umrah and Hajj seasons. Conclusion: This study period is considered extraordinary as the Saudi Arabian government has undertaken successful preventive measures that have had a great effect both on the spread of the pandemic and in reducing air pollution in Makkah. More studies are required to examine PAHs’ carcinogenic effects after the pandemic measures are eased across Makkah.

Establishing indicators for assessing non-carcinogenic risks under chronic inhalation expo-sure to benzene and average annual mpc for benzene as per health risk criteria

Recently multiple new toxicological and epidemiologic data on negative effects produced by chemicals have become available; given that, it is necessary to improve quantitative criteria applied in health risk assessment. It is advisable to revise previously established reference concentrations and to make more precise lists of organs and systems affected by a chemical in concentrations which are either equal to reference one or exceed it. Our research aim was to establish a reference concentration for benzene and additional quantitative indicators of its effects (additional reference concentrations) on specific organs and systems under chronic inhalation exposure; another aim was to determine average annual MPC verified as per permissible lifetime carcinogenic risk using evolution models. The research allowed recommending 0.005 mg/m3 to be used as a reference concentration under chronic inhalation exposure to benzene; a decrease in quantity of B-lymphocytes was recommended as a critical effect since this decrease might produce negative effects on the blood and immune system. Additional reference concen-trations for benzene were fixed at 0.007 mg/m3 for the liver as a critical organ and 0.012 mg/mg3 for violated process of organism development as a critical effect. They can be used as additional indicators for assessing non-carcinogenic health risks under chronic inhalation exposure to benzene in its elevated concentrations. Our research results were used to substantiate average annual MPC for benzene in ambient air; its recommended value was 0.005 mg/m3 since it provided safety (absence of impermis-sible (unacceptable) lifetime health risk), probable carcinogenic effects taken into account.

Self-efficacy in relation to the use of complementary and alternative medicine, lifestyle choices and cancer aetiology

Purpose This survey assesses cancer patients’ etiological concepts, lifestyle choices, use of complementary and alternative medicine (CAM), and self-efficacy, as well as associations between those. It aims to find patterns which may facilitate communication and understanding between patients and physicians. Methods 353 oncological patients attending lectures on CAM answered a questionnaire. Correlations were examined and an exploratory factor analysis conducted to identify comprehensive lay-etiological concepts among a list of potential carcinogenic factors. Results Patients considered scientifically proven agents as well as other non-carcinogenic influences to be responsible for their disease. An exploratory factor analysis yielded vague indications of possible underlying concepts but factors tend to include items that do not fit the pattern in terms of content. Higher self-efficacy correlated with healthy diet and sports, but not with use of CAM. No conclusive correlations emerged between lay-aetiological concepts and most other variables, but we found a tendency for higher self-efficacy among patients who assigned higher carcinogenic effects to tobacco and lower carcinogenic effects to fasting and physical trauma. Conclusion Interest in CAM can arise for many reasons that are not necessarily related to self-efficacy. Lay-aetiological concepts of cancer differ significantly from scientific ones. They are complex and presumably highly individualistic. Their connection to use of CAM methods, lifestyle choices and self-efficacy should be explored in more detail. Patient information and communication with clinicians need to address cancer patients’ individual aetiological concepts to further patient’s understanding not only of their diagnosis but also of the treatment as well.