Commercial formulations of pesticides are invariably not single ingredients. Instead they are cocktails of chemicals, composed of a designated pesticidal "active principle" and "other ingredients," ...with the latter collectively also known as "adjuvants." These include surfactants, antifoaming agents, dyes, etc. Some adjuvants are added to influence the absorption and stability of the active principle and thus promote its pesticidal action. Currently, the health risk assessment of pesticides in the European Union and in the United States focuses almost exclusively on the stated active principle. Nonetheless, adjuvants can also be toxic in their own right with numerous negative health effects having been reported in humans and on the environment. Despite the known toxicity of adjuvants, they are regulated differently from active principles, with their toxic effects being generally ignored. Adjuvants are not subject to an acceptable daily intake, and they are not included in the health risk assessment of dietary exposures to pesticide residues. Here, we illustrate this gap in risk assessment by reference to glyphosate, the most used pesticide active ingredient. We also investigate the case of neonicotinoid insecticides, which are strongly suspected to be involved in bee and bumblebee colony collapse disorder. Authors of studies sometimes use the name of the active principle (for example glyphosate) when they are testing a commercial formulation containing multiple (active principle plus adjuvant) ingredients. This results in confusion in the scientific literature and within regulatory circles and leads to a misrepresentation of the safety profile of commercial pesticides. Urgent action is needed to lift the veil on the presence of adjuvants in food and human bodily fluids, as well as in the environment (such as in air, water, and soil) and to characterize their toxicological properties. This must be accompanied by regulatory precautionary measures to protect the environment and general human population from some toxic adjuvants that are currently missing from risk assessments.
This paper presents the essential features of an efficient and environmentally attractive pyrolysis for used tyres valorisation with energy and material recovery. The problem of tyres management ...strongly affects not only the environmental protection but even the resources maintenance, since problems related to the depletion of resources, energy demand and waste management, are strictly connected and required an integrated approach. A general guideline for EU member states, aims to reach a zero post-consumer amount of tyre disposal in landfills before the end of 21st century, to optimize and expand the already well studied ways of their treatment and find new ones, in order to accomplish a balance between economy and environmental protection. In this context, thermal treatment of end of life tyres could play a relevant role for the recovery of resources (matter and/or energy). During the past 10–15 years, several fundamental and applied studies showed that if carefully controlled, tyre pyrolysis can produce a number of valuable products. The final destination of the pyrolysis solid residue largely influences the industrial applications of pyrolysis.
In a full-scale anaerobic digestion plant, agricultural residues are generally converted into biogas and digestate, the latter usually produced in large amount. Generally, biogas is converted into ...heat, often lost, and electricity, which is completely valorized or it is sold to the public grid. In this context, the aim of this study was to investigate the feasibility to combine anaerobic digestion and pyrolysis processes in order to increase the energy recovery from agricultural residues and the sustainability of the anaerobic digestion plant. Results revealed that heat excess produced during anaerobic digestion could cover the drying needs for the solid digestate, while pyrolysis of digestate at 500 °C resulted in 8.8 wt.%, 58.4 wt.% and 32.8 wt.% of syngas, oil and char, respectively. The LHV of syngas was 15.7 MJ N m−3, whereas pyrolysis oil exhibited a HHV of 23.5 MJ kg−1 after water extraction. The hybrid system operating in symbiosis could increase the production of electricity from 9896 kWhel day−1 to 14,066 kWhel day−1 corresponding to an increase of 42% compared to AD stand-alone plant.
The isolation of stably transfected cell lines suitable for the manufacture of biotherapeutic protein products can be an arduous process relying on the identification of a high expressing clone; this ...frequently involves transgene amplification and maintenance of the clones' expression over at least 60 generations. Maintenance of expression, or cell line stability, is highly dependent upon the nature of the genomic environment at the site of transgene integration, where epigenetic mechanisms lead to variable expression and silencing in the vast majority of cases. We have assessed four chromatin function modifying elements (A2UCOE, MAR X_S29, STAR40 and cHS4) for their ability to negate chromatin insertion site position effects and their ability to express and maintain monoclonal antibody expression. Each element was analysed by insertion into different positions within a vector, either flanking or between heavy chain (HC) and light chain (LC) antibody expression cassettes. Our results clearly show that the A2UCOE is the most beneficial element in this system, with stable cell pools and clones increasing antibody yields 6.5-fold and 6.75-fold respectively. Stability analysis demonstrated that the reduction in antibody expression, seen with cells transfected with the control vector over 120 generations, was mitigated in the clones containing A2UCOE-augmented transgenes. Analysis also showed that the A2UCOE reduced the amount of transgene promoter DNA methylation, which contributed to the maintenance of starting levels of expression.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Considering the 3D Ising universality class of the QCD critical endpoint, we use a universal effective action for the description of the baryon-number density fluctuations around the critical region. ...Calculating the baryon-number multiplicity moments and determining their scaling with system’s size, we show that the critical region is very narrow in the direction of the baryon chemical potential μ and wider in the temperature (T) direction. In this context, published experimental results on local proton density-fluctuation measurements, obtained by intermittency analysis in transverse momentum space in NA49 central A+A collisions at sNN=17.2 GeV (A=C,Si,Pb), restrict significantly the location (μc,Tc) of the QCD critical endpoint. The main constraint is provided by the freeze-out chemical potential of the Si+Si system, which shows nonconventional baryon density fluctuations. An indicative solution, ignoring experimental uncertainties, is 119 MeV≤Tc≤162 MeV, 252 MeV≤μc≤258 MeV.
The present study aims to demonstrate challenge-based innovations of ELTs depolymerization, show evidence of promising developments and improve pyrolysis performance towards its economic viability. A ...pyrolysis prototype, with a ELTs mass flow rate of 20 kg h−1 was designed, constructed, and demonstrated. Up to 100 kg h−1 of steel-free tyre granulates were pyrolyzed for up to 100 h continuous operation. The tests were carried out at 550 °C, under atmospheric pressure and residence time ∼12 min with good reliability and reproducibility. All three pyrolysis products showed good fuel characteristics. The LHV of the obtained producer gas estimated to 23.5 MJ Nm−3 and 26% of the prototype energy requirements were provided by using the producer gas as fuel. Pyro-oil showed high carbon content (86.04 wt%), GCV of 44.2 MJ kg−1 and H/C ratio (1.74). Despite its higher sulphur content, pyro-oil is comparable to diesel fuel in all other characteristics. Chars exhibited high percentage of fixed carbon (>80 wt %) and a high GCV = 30.3 MJ kg−1. S, Zn and Si were detected in chars, at low concentration. Based on surface and structural characteristics, chars were considered comparable to carbon blacks of N400-N500 series. Upgrading of char to activated carbon by physical and chemical activation, increased N2 surface area to 589 m2 g−1 and 402 m2 g−1, respectively. The study contributes significantly to increase knowledge on the viability of pyrolysis, providing to the recycling sector an opportunity for the deployment of take-off systems, within a Circular Economy. End of Life Tyres (ELTs) pyrolysis can be viable, if all produced streams are valorized.
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•ELTs pyrolysis for energy and carbon material recovery was demonstrated at TRL 7.•Pyro-gas provided 26% of the prototype energy requirements.•Pyro-char activated and its N2 surface area increased to 589 m2 g−1, suggesting it for environmental uses.•Puro-oil showed good characteristics to be used as fuel; standardisation is needed.•ELTs pyrolysis is viable, if all produced streams are valorized.
Anaerobic digestion (AD) is an established process for the treatment of organic wastes and the production of renewable energy. However, high amounts of digestate produced by AD plants require ...enhancement for further use. This study investigates a conceptual model for the digestate enhancement by using a downstream gasification. It is based on a ‘systemic approach’ considering the interactions of every contributing process into the dual system. The digestate was provided by an Italian AD plant, that treats mixed agricultural wastes of pig manure (43%), cow manure (20%), maize and triticale silages (25%), and cereal bran (12%). Digestate air gasification experiments were conducted, in a downdraft fixed-bed reactor, at temperature range from 750 °C to 850 °C, with λ varying from 0.14 to 0.34. Results have shown that gasification of digestate at 850 °C with λ = 0.24, increased producer gas yield (65.5 wt %), and its LHV (2.88 MJ Nm−3). The gas is classified as medium heating value fuel, suitable to generate electricity of 971 kWhel day−1 to enhance the AD plant's economic viability. A carbonaceous material rich in macronutrients (P, K, Ca, Mg) was produced, with R50 = 0.48, suitable for carbon sequestration. The study offers a resource closed loop approach of converting AD digestate into energy and soil fertilizer. Useful suggestions for policy makers and business can be drawn.
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•A dual system of AD and gasification with closed loop is proposed.•Heat surplus from AD process can fully cover solid digestate drying.•Gasification of digestate at 850 °C and at λ=0.24 resulted in best gas yield (65.5 wt %).•Coupling AD with pyrolysis produces more electricity than stand-alone AD.
The safety profile of the herbicide glyphosate and its commercial formulations is controversial. Reviews have been published by individuals who are consultants and employees of companies ...commercializing glyphosate-based herbicides in support of glyphosate's reapproval by regulatory agencies. These authors conclude that glyphosate is safe at levels below regulatory permissible limits. In contrast, reviews conducted by academic scientists independent of industry report toxic effects below regulatory limits, as well as shortcomings of the current regulatory evaluation of risks associated with glyphosate exposures. Two authors in particular (Samsel and Seneff) have published a series of commentaries proposing that long-term exposure to glyphosate is responsible for many chronic diseases (including cancers, diabetes, neuropathies, obesity, asthma, infections, osteoporosis, infertility, and birth defects). The aim of this review is to examine the evidential basis for these claimed negative health effects and the mechanisms that are alleged to be at their basis. We found that these authors inappropriately employ a deductive reasoning approach based on syllogism. We found that their conclusions are not supported by the available scientific evidence. Thus, the mechanisms and vast range of conditions proposed to result from glyphosate toxicity presented by Samsel and Seneff in their commentaries are at best unsubstantiated theories, speculations, or simply incorrect. This misrepresentation of glyphosate's toxicity misleads the public, the scientific community, and regulators. Although evidence exists that glyphosate-based herbicides are toxic below regulatory set safety limits, the arguments of Samsel and Seneff largely serve to distract rather than to give a rational direction to much needed future research investigating the toxicity of these pesticides, especially at levels of ingestion that are typical for human populations.
The herbicide active ingredient glyphosate can affect the growth of microorganisms, which rely on the shikimate pathway for aromatic amino acid biosynthesis. However, it is uncertain whether ...glyphosate exposure could lead to perturbations in the population of human gut microbiota. We have addressed this knowledge gap by analysing publicly available datasets to provide new insights into possible effects of glyphosate on the human gut microbiome. Comparison of the abundance of the shikimate pathway in 734 paired metagenomes and metatranscriptomes indicated that most gut bacteria do not possess a complete shikimate pathway, and that this pathway is mostly transcriptionally inactive in the human gut microbiome. This suggests that gut bacteria are mostly aromatic amino acid auxotrophs and thus relatively resistant to a potential growth inhibition by glyphosate. As glyphosate blocking of the shikimate pathway is via inhibition of EPSPS, we classified E. coli EPSPS enzyme homologues as class I (sensitive to glyphosate) and class II (resistant to glyphosate). Among 44 subspecies reference genomes, accounting for 72% of the total assigned microbial abundance in 2144 human faecal metagenomes, 9 subspecies have class II EPSPS. The study of publicly available gut metagenomes also indicated that glyphosate might be degraded by some Proteobacteria in the human gut microbiome using the carbon–phosphorus lyase pathway. Overall, there is limited experimental evidence available for the effects of glyphosate on the human gut microbiome. Further investigations using more advanced molecular profiling techniques are needed to ascertain whether glyphosate and glyphosate-based herbicides can alter the function of the gut microbiome with consequent health implications.
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•It is debated whether glyphosate can perturb the human gut microbiota•Gut microbiome EPSPS enzymes are predicted to be sensitive to glyphosate•Shikimate pathway is mostly transcriptionally inactive in the human gut microbiome•Most gut microbiome bacteria do not possess a complete shikimate pathway•Investigations using more advanced techniques such as metabolomics are needed
Taking under consideration the environmental boundaries but also the minimization of operating cost, End of Life Tyres (ELTs) depolymerization technology, via pyrolysis, can be characterized viable, ...under the condition of the effective valorization of every produced stream. This study aims to investigate which factors determine the path to activated carbon production from tyre-derived char, assuring that the received product will be of accepted quality, thus setting it as a commercially competitive product. To obtain current information on char activation, a comprehensive literature review was undertaken. An assessment based on process parameters, economic aspects and proposed uses of the produced activated carbons, was also presented. The proper selection of activation conditions (time, temperature, activating agent) results to a carbon adsorbent with prescript physical and chemical properties, suitable for specific applications. Towards energy self-sufficiency of the whole plant, a number of recommendations were made for the dual pyrolysis-activation scheme. Eventually, this would be an extra asset for the proposed valorization route of ELTs, via pyrolysis process.
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