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Bisphenol A (BPA) is an endocrine-disrupting chemical that has caught a lot of attention recently due to its toxicity and ubiquitous presence in the environment. Therefore, removal of BPA from contaminated environments such as water is of high importance. In this study, we prepared an alginate/pectin anode containing immobilized laccase and applied the anode in an electro-enzymatic oxidation system for BPA degradation. After 4 h, the laccase-alginate/pectin system demonstrated a much higher BPA removal efficiency (95%) than the similar system without immobilized laccase (50%, control system). The effects of humic acids (HA) on BPA degradation were also observed. HA might have accelerated the laccase-catalyzed coupling reaction between BPA and reactive radical intermediates, which resulted in increased BPA removal efficiency (92% after 150 min). It was demonstrated that laccase immobilization on an alginate/pectin electrode could greatly enhance BPA removal via electro-oxidation. Humic acids which are abundantly present in nature can also make this removal process faster. Overall, this study highlights the great application potential of laccase-immobilized bioelectrodes for BPA removal in conditions close to real life scenarios.

Vegetable crisps are usually perceived to be a healthier alternative to potato crisps, though thermal treatment can generate harmfull contaminants such as monochloropropanediol and glycidol fatty acid esters (MCPDEs and GEs) or acrylamide in these products. This study is among the first to investigate MCPDE, GEs, and acrylamide in commercial potato, sweet potato, parsnip, beetroot, and carrot crisps. These contaminants were found in all crisp samples on the market. The novel alternative vegetable crisps (n = 16) showed substasntial higher concentrations than in traditional potato crisps (n = 29), e.g. beetroot crisps had 7 times higher amount of 3-MCPDEs (mean 212 µg/kg), while acrylamide was 8 times higher in carrot crisps (mean 2893 µg/kg) and ∼3-4 times higher in beetroot, parsnip and sweet potato crisps. All vegetable crisp had mean values of acrylamide higher than European Commission established benchmark level for potato crisps at 750 µg/kg. Consequently, risk assessment demonstrated concerning Margin of Exposure (MoE) values for acrylamide exposure via crisp consumption in all age groups from 4-75. On the other hand, no apparent health risk was observed for dietary intake of 3-MCPDEs or GEs in crisps.

Excess bisphenol A (BPA) is a pollutant of concern in different water sources. In this work, magnetic illite clay-composite material (Fe3O4@illite) was synthesized via the coprecipitation method by loading Fe3O4 nanoparticles (nano-Fe3O4) onto the surfaces of illite clay. Results from different characterizations showed that nano-Fe3O4 was embedded into illite clay nanosheets and existed on the surfaces of illite clay, thereby reducing the degree of agglomeration and improving dispersibility. The catalytic BPA degradation of Fe3O4@illite and nano-Fe3O4 confirmed the superior performance of Fe3O4@illite compared with that of nano-Fe3O4. The optimum operating parameters for degradation were 0.3 mL of H2O2 at pH of 3 in the presence of Fe3O4@illite, which provided a maximum degradation capacity up to 816, 364, 113, and 68 mg/g for epoxy BPA concentration of resin wastewater (266 mg/L), synthetic wastewater (80 mg/L), Hefei City swan lake (25 mg/L), and Hefei University lake wastewater (14.94 mg/L), respectively, in 180 min reaction time. The degradation data conformed to the pseudo-first-order kinetic model. The degradation pathways and mineralization study revealed that the adsorption-Fenton-like reaction was the principal mechanism that demonstrated 100% degradation efficiency of Fe3O4@illite even after nine successive runs. The regeneration and reusability tendency analysis ensured that Fe3O4@illite can be easily separated by using magnets. Therefore, Fe3O4@illite composite with H2O2 Fenton-like technology was a promising method for BPA degradation.

This study investigated the effect of CaO2 pretreatment on sulfonamide antibiotics (SMs) remediation by Chlorella sp. Results showed that a CaO2 dose ranging from 0.05 to 0.1 g/g biomass was the best and led to higher SMs removal efficacy 5–10% higher than the control. The contributions made by cometabolism and CaO2 in SMs remediation were very similar. Bioassimilation could remove 24% of sulfadiazine (SDZ) and sulfamethazine (SMZ), and accounted for 38% of sulfamethoxazole (SMX) remediation. Pretreatment by CaO2 wielded a positive effect on microalgae. The extracellular polymeric substances (EPS) level of the CaO2 pretreatment microalgae was three times higher when subjected to non-pretreatment. For the long-term, pretreatment microalgae removed SMs 10–20% more than the non-pretreatment microalgae. Protein fractions of EPS in continuous operation produced up to 90 mg/L for cometabolism. For bioassimilation, SMX intensity of the pretreatment samples was 160-fold less than the non-treatment one. It indicated the CaO2 pretreatment has enhanced the biochemical function of the intracellular environment of microalgae. Peroxidase enzyme involved positively in the cometabolism and degradation of SMs to several metabolites including ring cleavage, hydroxylation and pterin-related conjugation.

A GC/MS-MS method for determination of monochloropropanediol (MCPDEs) and glycidol (GEs) was developed, validated, and applied to analyze 60 infant formula and baby food products commercially available on the Danish market. The contaminants were quantifiable in almost all sample categories with the exception of fruit or vegetable based purees. The highest concentrations of 3-MCPDEs and 2-MCPDEs were found in a baby biscuit product at 102.6 μg/kg and 52.8 μg/kg, respectively. Meanwhile, a baby puff item contained GEs as high as 149 μg/kg. MCPDEs and GEs concentrations are well correlated with each other in all sample types except puffs and biscuits. Occurrence data suggested that GEs formation might have taken place during production of baby puffs by unknown mechanisms. Preliminary exposure and risk assessment showed no apparent risk of Danish infants to these chemicals in formula and baby foods. However, special attention should be paid when feeding babies with puffs or similar items due to their relatively high level of GEs.

This study investigated the impacts of selective sole carbon source-induced micropollutants (MPs) cometabolism of Chlorella sp. by: (i) extracellular polymeric substance (EPS), superoxide dismutase and peroxidase enzyme production; (ii) MPs removal efficiency and cometabolism rate; (iii) MPs’ potential degradation products identification; and (iv) degradation pathways and validation using the Eawag database to differentiate the cometabolism of Chlorella sp. with other microbes. Adding the sole carbon sources in the presence of MPs increased EPS and enzyme concentrations from 2 to 100-fold in comparison with only sole carbon sources. This confirmed that MPs cometabolism had occurred. The removal efficiencies of tetracycline, sulfamethoxazole, and bisphenol A ranged from 16 to 99%, 32–92%, and 58–99%, respectively. By increasing EPS and enzyme activity, the MPs concentrations accumulated in microalgae cells also fell 400-fold. The cometabolism process resulted in several degradation products of MPs. This study drew an insightful understanding of cometabolism for MPs remediation in wastewater. Based on the results, proper carbon sources for microalgae can be selected for practical applications to remediate MPs in wastewater while simultaneously recovering biomass for several industries and gaining revenue.

Standard infant formula and specialised infant formula for medical purposes in Denmark (n = 42) were assessed for the levels of 2-MCPDEs, 3-MCPDEs, and GEs. Similar concentrations of GEs were observed in both standard and specialised powder infant formula at around 11.5 µg/kg. For 2-MCPDEs and 3-MCPDEs, significantly higher concentrations were observed in specialised products (18.0 and 49.8 µg/kg, respectively) in comparison with the standard ones (11.8 and 31.0 µg/kg, respectively). The concentration profiles also revealed discrepancies in MCPDEs and GEs concentrations not only between different manufacturers but also in terms of infant formula variety. For instance, the hypoallergenic powder formula showed twice as much MCPDEs as the normal formula variety. Exposure estimation using average contaminant concentrations in each variety suggested no potential risk of 3-MCPDEs and GEs intake for Danish infants via infant formula consumption. However, special attention is required for a few specific products where risks might occur in terms of 3-MCPDEs and/or GEs consumption.

Acetaminophen (ACT) is commonly used as a counter painkiller and nowadays, it is increasingly present in the natural water environment. Although its concentrations are usually at the ppt to ppm levels, ACT can transform into various intermediates depending on the environmental conditions. Due to the complexity of the ACT degradation products and the intermediates, it poses a major challenge for monitoring, detection and to propose adequate treatment technologies. The main objectives of this review study were to assess (i) the occurrences and toxicities, (2) the removal technologies and (3) the transformation pathways and intermediates of ACT in four environmental compartments namely wastewater, surface water, ground water, and soil/sediments. Based on the review, it was observed that the ACT concentrations in wastewater can reach upto several hundreds of ppb. Amongst the different countries, China and the USA showed the highest ACT concentration in wastewater (≤ 300 μg/L), with a very high detection frequency (81-100%). Concerning surface water, the ACT concentrations were found to be at the ppt level. Some regions in France, Spain, Germany, Korea, USA, and UK comply with the recommended ACT concentration for drinking water (71 ng/L). Notably, ACT can transform and degrade into various metabolites such as aromatic derivatives or organic acids. Some of them (e.g., hydroquinone and benzoquinone) are toxic to human and other life forms. Thus, in water and wastewater treatment plants, tertiary treatment systems such as advanced oxidation, membrane separation, and hybrid processes should be used to remove the toxic metabolites of ACT.

The selective expression of CD137 on cells of the immune system (e.g., T and DC cells) and oncogenic cells in several types of cancer leads this molecule to be an attractive target to discover cancer immunotherapy. Therefore, specific antibodies against CD137 are being studied and developed aiming to activate and enhance anti-cancer immune responses as well as suppress oncogenic cells. Accumulating evidence suggests that anti-CD137 antibodies can be used separately to prevent tumor in some cases, while in other cases, these antibodies need to be co-administered with other antibodies or drugs/vaccines/regents for a better performance. Thus, in this work, we aim to update and discuss current knowledge about anti-cancer effects of anti-CD137 antibodies as mono- and combined-immunotherapies.