Potential Human Carcinogens Research Articles

Deciphering Aflatoxin B1 affected critical molecular pathways governing cancer: A bioinformatics study using CTD and PANTHER databases.

Aflatoxin B1 (AFB1) is a fungal toxin consistently found as a contaminant in food products such as cereals, nuts, spices, and oilseeds. AFB1 exposure can lead to hepatotoxicity, cancer, immune suppression, reproductive deficiency, nutritional dysfunction, and growth impairment. AFB1 has also been listed as one of the most potent human carcinogens by the International Agency for Research on Cancer. Although the correlation between AFB1 exposure and cancer initiation and progression is already reported in the literature, very little information is available about what molecular pathways are affected during cancer development. Considering this, we first selected AFB1-responsive genes involved in five deadliest cancer types including lung, colorectal, liver, stomach, and breast cancers from the Comparative Toxicogenomics Database (CTD). Then, using the PANTHER database, a statistical overrepresentation test was performed to identify the significantly affected pathways in each cancer type. The gonadotropin-releasing hormone receptor (GnRHR) pathway, the CCKR signaling pathway, and angiogenesis were found to be the most affected pathways in lung, breast, liver, and stomach cancers. In addition, AFB1 toxicity majorly impacted apoptosis and Wnt signaling pathways in liver and stomach cancers, respectively. Moreover, the most affected pathways in colorectal cancer were the Wnt, CCKR, and GnRHR pathways. Furthermore, gene analysis was also performed for the most affected pathways associated with each cancer and identified thirteen key genes (e.g., FOS, AKT1) that may serve as biological markers for a particular type of AFB1-induced cancer as well as for in vitro AFB1 toxicological studies using specific cancer cell lines.

Ochratoxin A and Its Role in Cancer Development: A Comprehensive Review.

Background: Ochratoxin A (OTA) is widely recognized for its broad spectrum of toxic effects and is classified as a potential human carcinogen, placed in group 2B by the International Agency for Research on Cancer (IARC). Its presence in food and beverages poses a significant health hazard. Extensive research has documented the efficient absorption and distribution of OTA throughout the body via the bloodstream and tissues, underscoring the associated health risk. Additionally, ongoing studies aim to clarify the link between OTA exposure and carcinogenesis. The obtained results indicate a strong correlation between OTA and renal cell carcinoma (RCC), with potential associations with other malignancies, including hepatocellular carcinoma (HCC), gallbladder cancer (GBC), and squamous cell carcinoma (SCC). OTA is implicated in oxidative stress, lipid peroxidation, apoptosis, DNA damage, adduct formation, miRNA deregulation, and distributions in the cell cycle, all of which may contribute to carcinogenesis. Conclusions: Despite significant research efforts, the topic remains inexhaustible and requires further investigation. The obtained results do not yield definitive conclusions, potentially due to species-specific differences in the animal models used and challenges in extrapolating these results to humans. In our review, we delve deeper into the potential mechanisms underlying OTA-induced carcinogenesis and discuss existing limitations, providing directions for future research.

Ecological implications of chromium-contaminated effluents from Indian tanneries and their phytoremediation: a sustainable approach.

Industrial activities are paramount to sustaining the economy in a rapidly developing nation and global powerhouse like India. Leather industries are important in the country's economic map due to the high revenue and employment generation opportunities. Several of these industries contribute largely to environmental pollution. The pollution of the environment is mainly caused by improper disposal of the tannery effluents that are highly rich in hexavalent chromium, a potent human carcinogen. Hexavalent chromium imparts toxic effects on the biotic components, which include plants, animals, and humans. The review portrays the current status of the Indian leather tanning sector and its impact on the Indian economy. The process of chromium tanning and its adverse effects on the environmental biotic components have been briefly discussed. Phytoremediation of these effluents using suitable hyperaccumulating plants has been suggested as an eco-friendly and cost-effective approach for the sustainable restoration of the polluted environment. The mechanism behind the remediation approach and the factors influencing it have been detailed. The manuscript briefly discusses some important advancements in the field of phytoremediation and emerging technologies and concludes by emphasizing further research for sustainable management of tannery wastes.

The food-borne carcinogenic 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) disrupts circadian rhythms and ameliorated by pterostilbene (PSB) in Caenorhabditis elegans.

The food-borne 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is a potential human carcinogen abundant in cooked meat. While circadian rhythms are crucial biological oscillations, the negative impact of PhIP on circadian systems and the potential of mitigation remain underexplored. We investigated the effects of PhIP on circadian rhythms and the mitigating effects of the phytochemical antioxidant pterostilbene (PSB) in Caenorhabditis elegans. We show that exposure to 10μM PhIP disrupts the 24-h circadian rhythms of C. elegans, an effect mitigated by co-exposure to 100μM PSB. In addition, PhIP-induced circadian disruption can be linked to defective oxidative stress resistance, which is associated with the DAF-16/FOXO pathway and is modulated by PSB. Molecular docking suggested that PhIP and PSB bind similarly to DAF-16. Moreover, 10μM PhIP abolished the rhythmic expression of the core clock gene prdx-2, which is restored by 100μM PSB. Findings from this study provide novel insight of how food-borne contaminant like PhIP may contribute to the disruption of circadian rhythms and suggest potential for PSB to mitigate these effects in higher organisms.

The Trend in Mitigation Strategies of 3-Monochloropropane-1,2-diol and Glycidyl Esters in Edible Vegetable Oils: Today and Tomorrow.

3-Monochloropropane-1,2-diol (3-MCPD) and its esters, which have carcinogenic and genotoxic effects, are contaminants induced by high-temperature that have been detected in refined oils and fatty foods. 3-MCPD esters, chlorinated propanols, were first identified in 1978 in acid-hydrolysed vegetable proteins used as flavour enhancers in many foods. Glycidyl esters (GE) are contaminants that can occur in edible oils during heat treatment and are formed mainly during the deodorisation phase of refining. The International Agency for Research on Cancer has classified 3-MCPD as a 'potential carcinogen for humans' in group 2B. Glycidol has also been classified as group 2A with mutagenic and carcinogenic properties, i.e. 'probably carcinogenic to humans'. In addition, glycidol has been classified by the International Agency for Research on Cancer (IARC) as a 'possible human carcinogen' (group 2A). Toxicological studies have shown that these genotoxic and carcinogenic contaminants induced by heat treatment are released in the gastrointestinal tract and cause the formation of tumours. In this review the mechanisms of formation, toxicological effects of 3-MCPD and GE on human health, and methods of their detection are shown. The latest strategies to mitigate and prevent 3-MCPD and GE formation during crude oil production, refining and beyond are also discussed.

Cell proliferation and carcinogenesis: an approach to screening for potential human carcinogens.

Cancer arises from multiple genetic errors occurring in a single stem cell (clonality). Every time DNA replicates, mistakes occur. Thus, agents can increase the risk of cancer either by directly damaging DNA (DNA-reactive carcinogens) or increasing the number of DNA replications (increased cell proliferation). Increased cell proliferation can be achieved either by direct mitogenesis or cytotoxicity with regenerative proliferation. Human carcinogens have a mode of action of DNA reactivity, immunomodulation (mostly immunosuppression), increased estrogenic activity (mitogenesis), or cytotoxicity and regeneration. By focusing on screening for these four effects utilizing in silico, in vitro, and short-term in vivo assays, a biologically based screening for human chemical carcinogens can be accomplished with greater predictivity than the traditional 2-year bioassay with considerably less cost, less time, and the use of fewer animals.

Depletion of Free Chlorine and Generation of Trichloromethane in the Presence of pH Control Agents in Chlorinated Water at pH 6.5

Chlorine is commonly used by the fresh produce industry to sanitize water and minimize pathogen cross-contamination during handling. The pH of chlorinated water is often reduced to values of pH 6–7, most commonly with citric acid to stabilize the active antimicrobial, hypochlorous acid (a form of free chlorine). Previous studies have demonstrated that citric acid reacts with chlorine to form trichloromethane, a major chlorine by−product in water and a potential human carcinogen. However, it is unclear if other pH control agents could be used in the place of citric acid to minimize the formation of trichloromethane. The objective of the present study was to determine the reactivity of organic and inorganic pH control agents, with chlorine, to generate trichloromethane. Free chlorine (∼100 mg/L) was mixed with 10 mM of each of twelve organic acids and two inorganic pH control agents (i.e., sodium acid sulfate and phosphoric acid) to effect a pH level of 6.5. Free chlorine and trichloromethane levels were measured over 3 h at 3 and 22°C. Results demonstrated that ascorbic acid, dehydroascorbic acid, citric acid, and malic acid rapidly depleted free chlorine concentrations at both 22°C and 3°C, while tartaric acid and lactic acid decreased chlorine concentrations more slowly. Other pH control agents did not significantly reduce free chlorine either at 22 or 3°C. Citric acid led to the generation of significantly higher concentrations of trichloromethane than did other acids. Chloroacetone was also found in chlorinated water in the presence of citric acid and ascorbic acid. Taking buffering capacity and pKa values into account, phosphoric acid and some organic acids may be used to replace citric acid as pH control agents in chlorinated water for washing fresh produce, to stabilize free chlorine level and reduce the generation of trichloromethane.

Estimating impacts of reducing acrylonitrile exposure on lung cancer mortality in an occupational cohort with the parametric g-formula

ObjectivesTo inform the potential human carcinogenicity of acrylonitrile, we estimate associations between acrylonitrile exposures and lung cancer mortality in US workers with the objectives of (1) assessing potential for healthy...

Considering Grouped or Individual Non-Methane Volatile Organic Compound Emissions in Life Cycle Assessment of Composting Using Three Life Cycle Impact Assessment Methods

Composting is a waste management practice that converts organic waste into a product that can be used safely and beneficially as a bio-fertiliser and soil amendment. Non-methane volatile organic compounds (NMVOCs) from composting are known to cause damage to human health and the environment. The impact of waste management on the environment and workers is recognised as a growing environmental and public health concern. Measurements of NMVOCs emitted during composting have been carried out only in a few studies. NMVOC emissions are typically reported as a group rather than as species or speciation profiles. Recognising the need to investigate the issues associated with NMVOCs, the objective of this study is to estimate variation in life cycle assessment (LCA) results when NMVOCs are considered individual emissions compared to grouped emissions and to compare midpoint and endpoint life cycle impact assessment (LCIA) methods. In general, the ReCiPe 2016 LCIA method estimated the highest impact from the composting process in comparison to IMPACT World+ and EF 3.0 for the impact categories of ozone formation, stratospheric ozone depletion, and particulate matter formation. For ReCiPe 2016 and IMPACT World+, the NMVOC emissions were not linked to human toxicity characterisation factors, meaning that the contribution from NMVOC towards human health risks in and around composting facilities could be underestimated. Using individual NMVOCs helps to additionally estimate the impacts of composting on freshwater ecotoxicity and human carcinogenic and non-carcinogenic toxicity potential. If ecotoxicity or toxicity issues are indicated, then LCA should be accompanied by suitable risk assessment measures for the respective life cycle stage.

Electrochemical reductive removal of trichloroacetic acids by a three-dimensional binderless carbon nanotubes/ CoP/Co foam electrode: Performance and mechanism

Numerous chlorinated disinfection by-products (DBPs) are produced during the chlorination disinfection of water. Among them, chloroacetic acids (CAAs) are of great concern due to their potential human carcinogenicity. In this study, effective electrocatalytic dechlorination of trichloroacetic acids (TCAA), a typical CAAs, was achieved in the electrochemical system with the three-dimensional (3D) self-supported CoP on cobalt foam modified by carbon nanotubes (CNT/CoP/CF) as the cathode. At a 10 mA cm−2 current density, 74.5% of TCAA (500 μg L−1) was converted into AA within 100 min. In-situ growth of CoP increased the effective electrochemical surface area of the electrode. Electrodeposited CNT promoted electron transfer from the electrode surface to TCAA. Therefore, the production of surface-adsorbed atomic hydrogen (H*) on CNT/CoP/CF was improved, further resulting in excellent electrochemical dechlorination of TCAA. The dechlorination pathway of TCAA proceeded into acetic acids via direct electronic transfer and H*-mediated reduction on CNT/CoP/CF electrode. Additionally, the electroreduction efficiency of CNT/CoP/CF for TCAA exceeded 81.22% even after 20 cycles. The highly efficient TCAA reduction performance (96.57%) in actual water revealed the potential applicability of CNT/CoP/CF in the complex water matrix. This study demonstrated that the CNT/CoP/CF is a promising non-noble metal cathode to remove chlorinated DBPs in practice.

Mass Spectrometry-Based Method to Measure Aflatoxin B1 DNA Adducts in Formalin-Fixed Paraffin-Embedded Tissues.

Aflatoxin B1 (AFB1) is a potent human liver carcinogen produced by certain molds, particularly Aspergillus flavus and Aspergillus parasiticus, which contaminate peanuts, corn, rice, cottonseed, and ground and tree nuts, principally in warm and humid climates. AFB1 undergoes bioactivation in the liver to produce AFB1-exo-8,9-epoxide, which forms the covalently bound cationic AFB1-N7-guanine (AFB1-N7-Gua) DNA adduct. This adduct is unstable and undergoes base-catalyzed opening of the guanine imidazolium ring to form two ring-opened diastereomeric 8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy-aflatoxin B1 (AFB1-FapyGua) adducts. The AFB1 formamidopyrimidine (Fapy) adducts induce G → T transversion mutations and are likely responsible for the carcinogenic effects of AFB1. Quantitative liquid chromatography-mass spectrometry (LC-MS) methods have shown that AFB1-N7-Gua is eliminated in rodent and human urine, whereas ring-opened AFB1-FapyGua adducts persist in rodent liver. However, fresh frozen biopsy tissues are seldom available for biomonitoring AFB1 DNA adducts in humans, impeding research advances in this potent liver carcinogen. In contrast, formalin-fixed paraffin-embedded (FFPE) specimens used for histopathological analysis are often accessible for molecular studies. However, ensuring nucleic acid quality presents a challenge due to incomplete reversal of formalin-mediated DNA cross-links, which can preclude accurate quantitative measurements of DNA adducts. In this study, employing ion trap or high-resolution accurate Orbitrap mass spectrometry, we demonstrate that ring-opened AFB1-FapyGua adducts formed in AFB1-exposed newborn mice are stable to the formalin fixation and DNA de-cross-linking retrieval processes. The AFB1-FapyGua adducts can be detected at levels comparable to those in a match of fresh frozen liver. Orbitrap MS2 measurements can detect AFB1-FapyGua at a quantification limit of 4.0 adducts per 108 bases when only 0.8 μg of DNA is assayed on the column. Thus, our breakthrough DNA retrieval technology can be adapted to screen for AFB1 DNA adducts in FFPE human liver specimens from cohorts at risk of this potent liver carcinogen.

Role of Carbonyl Compounds for N-Nitrosamine Formation during Nitrosation: Kinetics and Mechanisms.

N-Nitrosamines are potential human carcinogens frequently detected in natural and engineered aquatic systems. This study sheds light on the role of carbonyl compounds in the formation of N-nitrosamines by nitrosation of five secondary amines via different pathways. The results showed that compared to a control system, the presence of formaldehyde enhances the formation of N-nitrosamines by a factor of 5-152 at pH 7, depending on the structure of the secondary amines. Acetaldehyde showed a slight enhancement effect on N-nitrosamine formation, while acetone and benzaldehyde did not promote nitrosation reactions. For neutral and basic conditions, the iminium ion was the dominant intermediate for N-nitrosamine formation, while carbinolamine became the major contributor under acidic conditions. Negative free energy changes (<-19 kcal mol-1) and relatively low activation energies (<18 kcal mol-1) of the reactions of secondary amines with N2O3, iminium ions with nitrite and carbinolamines with N2O3 from quantum chemical computations further support the proposed reaction pathways. This highlights the roles of the iminium ion and carbinolamine in the formation of N-nitrosamines during nitrosation in the presence of carbonyl compounds, especially in the context of industrial wastewater.

The probable reasons of arsenic susceptibility in a chronically exposed population of West Bengal

Arsenic is potent human carcinogen which affects millions of people across the globe. Arsenic induced pre-cancerous and cancerous skin lesions are hall marks of chronic arsenic toxicity. Even then, only 15%–20% of the population manifest arsenic-induced skin lesions but the rest do not, the reason for which in not very clear. Not only that, conjunctival irritations of the eyes, peripheral neuropathy and respiratory distress are the non-dermatological health effects which are often manifested in them in addition to the cancers of skin and other internal organs. In this work we have considered 233 arsenic exposed individuals with skin lesions and 205 arsenic exposed individuals without skin lesions from the highly arsenic affected Murshidabad district of West Bengal. We have compared arsenic exposure in the two groups through drinking water. Both the study groups have similar levels of arsenic exposure, drinking same arsenic laden water. Results show that higher amounts of arsenic were retained in the nails and hair of the skin lesion group compared to the no skin lesion group. Significant higher amounts of chromosomal aberration and micronucleus formation were found in the skin lesion group, than the no skin lesion group. Incidences of conjunctival irritations of the eyes, peripheral neuropathy and respiratory distress were much higher in the former group compared to the later. We, thus found that one group was more susceptible than the other, even with similar levels of arsenic exposure. We have tried to identify and discuss the probable reasons for this observation with reference to our previous works in the exposed population from West Bengal, India.

Nitrosamine Impurity: Management of Unwelcome Guest in Pharma Market

Nitrosamine impurities have been detected in various pharmaceutical products in recent days. Various sartans, ranitidine, nizatidine and metformin have been recalled from the markets due to the high limit of nitrosamine impurities. When assessing the danger of human cancer, pharmaceutical products ability to regulate potentially mutagenic and carcinogenic contaminants is crucial. The risk of their mutagenic and carcinogenic potential has increased with the recent finding of nitrosamine impurities in various commercially available medications. Nitrosamine is the substance deemed to be a potential human carcinogen by the International Agency for Research on Cancer (IARC). Impurities in nitrosamines have been shown to be mutagenic and carcinogenic; even very low exposure levels to these impurities can cause cancer. These impurities may be created by a reagent, catalyst, solvent, or raw materials employed in the manufacturing process and end up in drug substances or drug products. Angiotensin II receptor blocker (ARB) medications with nitrosamine impurities have caused widespread health problems. Risk management of nitrosamine impurity is necessary to control the level of this impurity in drug substance, drug product and APIs. By using risk management tools like fishbone diagram which is used to identify and organize the possible sources of nitrosamines in medicines. For detection of nitrosamine impurity different countries develops their own analytical methods.

ALDH2 dysfunction and alcohol cooperate in cancer stem cell enrichment.

The alcohol metabolite acetaldehyde is a potent human carcinogen linked to esophageal squamous cell carcinoma (ESCC) initiation and development. Aldehyde dehydrogenase 2 (ALDH2) is the primary enzyme that detoxifies acetaldehyde in the mitochondria. Acetaldehyde accumulation causes genotoxic stress in cells expressing the dysfunctional ALDH2E487K dominant negative mutant protein linked to ALDH2*2, the single nucleotide polymorphism highly prevalent among East Asians. Heterozygous ALDH2*2 increases the risk for the development of ESCC and other alcohol-related cancers. Despite its prevalence and link to malignant transformation, how ALDH2 dysfunction influences ESCC pathobiology is incompletely understood. Herein, we characterize how ESCC and preneoplastic cells respond to alcohol exposure using cell lines, three-dimensional organoids and xenograft models. We find that alcohol exposure and ALDH2*2 cooperate to increase putative ESCC cancer stem cells with high CD44 expression (CD44H cells) linked to tumor initiation, repopulation and therapy resistance. Concurrently, ALHD2*2 augmented alcohol-induced reactive oxygen species and DNA damage to promote apoptosis in the non-CD44H cell population. Pharmacological activation of ALDH2 by Alda-1 inhibits this phenotype, suggesting that acetaldehyde is the primary driver of these changes. Additionally, we find that Aldh2 dysfunction affects the response to cisplatin, a chemotherapeutic commonly used for the treatment of ESCC. Aldh2 dysfunction facilitated enrichment of CD44H cells following cisplatin-induced oxidative stress and cell death in murine organoids, highlighting a potential mechanism driving cisplatin resistance. Together, these data provide evidence that ALDH2 dysfunction accelerates ESCC pathogenesis through enrichment of CD44H cells in response to genotoxic stressors such as environmental carcinogens and chemotherapeutic agents.

Mitochondrial and Proteasome Dysfunction Occurs in the Hearts of Mice Treated with Triazine Herbicide Prometryn.

Prometryn is a methylthio-s-triazine herbicide used to control the growth of annual broadleaf and grass weeds in many cultivated plants. Significant traces of prometryn are documented in the environment, mainly in waters, soil, and plants used for human and domestic consumption. Previous studies have shown that triazine herbicides have carcinogenic potential in humans. However, there is limited information about the effects of prometryn on the cardiac system in the literature, or the mechanisms and signaling pathways underlying any potential cytotoxic effects are not known. It is important to understand the possible effects of exogenous compounds such as prometryn on the heart. To determine the mechanisms and signaling pathways affected by prometryn (185 mg/kg every 48 h for seven days), we performed proteomic profiling of male mice heart with quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS) using ten-plex tandem mass tag (TMT) labeling. The data suggest that several major pathways, including energy metabolism, protein degradation, fatty acid metabolism, calcium signaling, and antioxidant defense system were altered in the hearts of prometryn-treated mice. Proteasome and immunoproteasome activity assays and expression levels showed proteasome dysfunction in the hearts of prometryn-treated mice. The results suggest that prometryn induced changes in mitochondrial function and various signaling pathways within the heart, particularly affecting stress-related responses.

Environmental impacts of graphene at industrial production scale and its application in electric heating technology

Although graphene has shown great promise in various fields with advantageous performance, the potential environmental impacts of the consequent large-scale production and application are of increasing concern. However, most studies have focused on laboratory-scale or hypothetical mass manufacture of graphene. This study evaluates the environmental impacts of graphene at industrial production scale based on actual factory and its application in electric heating technology using the life cycle assessment. Results show that electricity is the hotspot of environmental impacts for graphene and the novel graphene electric heating element, and their impact categories concentrate on global warming potential, fine particulate matter formation potential, human carcinogenic toxicity potential, and human non-carcinogenic toxicity potential. The thermal exfoliation route has significantly superior potential environmental performances than the oxidation–reduction route in industrial production of graphene. The environmental burdens of graphene and its electric heating applicants would further reduce in the future.

EVALUATION OF OCCUPATIONAL EXPOSURE TO TIO2 NANOPARTICLES: MICROWAVE-ASSISTED ACID DIGESTION METHOD ON AIR MEMBRANE FILTERS

Titanium dioxide (TiO2) nanoparticles have been extensively used in various industrial sectors and applications, including cosmetics, catalysts, food additives, inks, paints, and coatings. However, the International Agency for Research on Cancer (IARC) has classified TiO2 nanoparticles as a potential carcinogen for humans, meaning they may cause cancer and pose serious health complications, particularly for manufacturing workers. This highlights the need for better evaluation to determine worker exposure. In this study, suspended TiO2 nanoparticles were sampled using a nanoparticle respiratory deposition (NRD) sampler fitted with specially designed membrane filters and analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The digestion method used for titanium element recovery after nanoparticle sampling is crucial for optimal ICP-MS analysis. Therefore, this study aimed to investigate the most suitable digestion method. A microwave-acid digestion method using concentrated nitric acid and concentrated hydrochloric acid at a 7:4 ratio, with a run time of 30 minutes and the temperature set to 200°C showed remarkable titanium recovery compared to other methods. These findings may pave the way for optimal analysis of suspended TiO2 nanoparticles in assessing occupational exposure while promoting sustainability and eco-friendliness in resource utilization.

Influence of chemically synthesized TiO2 nanoparticles for photocatalytic degradation of herbicide atrazine

The selective triazine herbicide atrazine is effective against several grassy and broad-leaf weeds. Because of its poor rate of biodegradability, atrazine herbicide is minimally present in aquatic environments. Despite atrazine's low water solubility, pollution of water resources with extremely hazardous herbicides is a major concern. Long-term negative effects of atrazine include hepatotoxicity, renal toxicity, endocrine disruption, a potential human carcinogen, and impaired vitamin function. The benefits of titanium dioxide include chemical stability, non-toxicity, cost, water insolubility, optical properties, and, most crucially, the ability to be recycled. To improve photocatalytic activity, broaden the UV spectral range to visible light, and inhibit electron-hole recombination, titanium dioxide catalysts are doped with metal and non-metal ions. Titanium oxide nanoparticles have a large specific surface area that ranges from 50 to more than 300 m2 g−1, which increases their ability of adsorption and photocatalysis.In this study, different analysis techniques were employed to characterize TiO2 nanoparticles that includes, scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) (before and after experimental investigation). The produced TiO2 nanoparticles were found to be between 200 and 250 nm in size, and the diffraction peaks of TiO2 nanoparticles from XRD analysis are revealed by the peaks at 38.5, 41, 46.5, 63, 74, and 77, respectively and The size of the particles is determined by SEM examination. The optimum process conditions i.e. time − 60 min, rpm of 600, dosage of 1 g/L of catalyst, pH 6, initial concentration of 200 ppm, and temperature of 70 °C. Based on the data obtained in this study, the percentage degradation of Atrazine was determined and was found to be 76.15%.

Effect of frying temperature and slice thickness on sensory attributes and acrylamide content in potato crisps of selected Kenyan varieties

Acrylamide, a chemical found in several carbohydrates rich foods processed at high temperatures, has been classified as a potential human carcinogen; the need to minimize its presence in the human diet cannot be overemphasized. This study was designed to determine how acrylamide formation is influenced by potato varieties, processing temperatures and slice thickness in potato crisp produced from established Kenyan varieties. Four potato varieties (Kenya Mpya, Sheherekea, Tigoni and Dutch Robjin) were purposively selected due to their suitability for crisp production and were planted at KARLO Tigoni. The potato tubers were harvested at maturity, cured, peeled and sliced into three slice thicknesses (1-0mm, 1.5mm and 2.00mm) and subjected to three frying temperatures of 160°C, 170°C and 180°C until ready. The dry matter of the tubers ranged between 21.5 and 28.4%. The fructose levels ranged from 0.068 - 0.241 %; glucose levels ranged 0.155%- 0.218%; Sucrose levels ranged from 0.61 to 0.87%. In the potato crisps Kenya Mpya variety fried at 160°C of thickness 2.0mm had the highest moisture content of 2.575%. Most of the crisps from the four varieties processed at different temperatures and thicknesses were light colored with lightness (L*) parameters greater than 50 and towards red as shown by positive values of redness parameter (a*) indicating that there was excess browning of the products during frying. Acrylamide levels significantly (P≤0.05) differed between the varieties and ranged from 3129 to 13480ppb. There was a significant difference in acrylamide levels (p≤0.05) with temperatures of 180°C resulting in higher acrylamide content compared to those of 160°C and 170°C. Similarly, the slice thickness of 2.0mm had high acrylamide levels and the redness parameter (a*). There was a strong correlation between acrylamide formation and glucose (r=0.761) and fructose (r=0.44) formation.