Understanding How Chemical Pollutants Arise and Evolve in the Brewing Supply Chain: A Scoping Review.

In this study, a critical review was carried out using the Web of ScienceTM Core Collection database to analyse the scientific literature published to date to identify lines of research and future perspectives on the presence of chemical pollutants in beer brewing. Beer is one of the world's most popular drinks and the most consumed alcoholic beverage. However, a widespread challenge with potential implications for human and animal health is the presence of physical, chemical, and/or microbiological contaminants in beer. Biogenic amines, heavy metals, mycotoxins, nitrosamines, pesticides, acrylamide, phthalates, bisphenols, microplastics, and, to a lesser extent, hydrocarbons (aliphatic chlorinated and polycyclic aromatic), carbonyls, furan-derivatives, polychlorinated biphenyls, and trihalomethanes are the main chemical pollutants found during the beer brewing process. Pollution sources include raw materials, technological process steps, the brewery environment, and packaging materials. Different chemical pollutants have been found during the beer brewing process, from barley to beer. Brewing steps such as steeping, kilning, mashing, boiling, fermentation, and clarification are critical in reducing the levels of many of these pollutants. As a result, their residual levels are usually below the maximum levels allowed by international regulations. Therefore, this work was aimed at assessing how chemical pollutants appear and evolve in the brewing process, according to research developed in the last few decades.

Comprehensive Review on Monitoring, Behavior, and Impact of Pesticide Residues during Beer-Making.

This paper reviews the impact of beer-making stages (malting, mashing, boiling, and fermentation) on the behavior of pesticide residues. The large use of pesticides on barley and hop could cause the occurrence of their residues in beer. The foremost factors influencing the stability of residues (pH, temperature, and water content) and the physical-chemical properties of pesticides (octanol-water partition coefficient, vapor pressure, and water solubility) are essential to know their final fate. Most pesticides show a decrease in the unhopped wort because they are adsorbed onto the spent grains after mashing. In addition, their concentrations decrease during boiling and fermentation. Generally, maltsters should dedicate particular attention to the residues of hydrophobic pesticides because they can remain on the malt. Contrarily, brewers should control residues of hydrophilic pesticides because they can be carried over into young beer, disturbing the quality and organoleptic properties (flavor, aroma, taste, or color) of the beer.

Removal assessment of disinfection by-products (DBPs) from drinking water supplies by solar heterogeneous photocatalysis: A case study of trihalomethanes (THMs).

Solar heterogeneous photocatalysis was used to remove trihalomethanes (THMs) from drinking water. THMs, mainly trichloromethane (TCM), tribromomethane (TBM), bromodichloromethane (BDCM) and dibromochloromethane (DBCM) are one of the main class of disinfection by-products (DBPs). THMs were determined by HSGC-MS with detection limits (LODs) ranging from 0.5 µg L-1 to 0.9 µg L-1 for TCM and BDCM, respectively. Results show that a great proportion of THMs present in water are finally transferred to air as a result of their high volatility in the order TCM > BDCM > DBCM > TBM. The use of band-gap semiconductor materials (TiO2 and mainly ZnO) used as photocatalysts in combination with Na2S2O8 as electron acceptor and sulfate radical anion (SO4•-) generator enhanced the photooxidation of all THMs as compared to photolytic test. The time required for 50% of THMs to disappear (DT50) from water calculated for the most effective treatment (ZnO/Na2S2O8) were 12, 42, 57 and 61 min for TCM, TBM, BDCM, and DBCM, respectively. Therefore, solar heterogeneous photocatalysis can be considered as an interesting strategy for THMs removal, especially in sunny areas like Mediterranean basin.

Photocatalytic degradation of four insecticides and their main generated transformation products in soil and pepper crop irrigated with reclaimed agro-wastewater under natural sunlight.

This work is the first-ever study of the concurrence of four insecticides (chlorantraniliprole, imidacloprid, pirimicarb and thiamethoxam) and their main transformation products (TPs) in soil and pepper crop irrigated with reclaimed and non-reclaimed water under agricultural field conditions. Field experiments were conducted using different irrigation supplies: control water (CW), wastewater polluted with phytosanitary commercial products containing the studied insecticides (WW) and reclaimed wastewater after a photocatalytic processing with TiO2/Na2S2O8 at pilot plant under sunlight (RWW). Photocatalytic treatments removed most of the insecticides and their TPs generated during the photoperiod. Neither target insecticides nor their TPs were detected in pepper samples when CW and RWW were used as irrigation source, whereas the four insecticides and two TPs were detected when WW was used. In the experiment carried out with WW, all insecticides and eight TPs were detected in soil samples. The impact of using reclaimed water on the quality of pepper crop was also assessed, showing barely any significant difference.

Mobility of insecticide residues and main intermediates in a clay-loam soil, and impact of leachate components on their photocatalytic degradation.

This work assesses the behavior (adsorption, degradation and leaching) of four insecticides (chlorantraniliprole, thiametoxam, imidacloprid and pirimicarb) and their main reaction intermediates in a clay-loam textured soil (1.6% OM). Following the batch equilibrium method, the KOC (as log values) ranged from 1.2 to 3.9 (thiametoxam and pirimicarb, respectively). All the insecticides were moderately persistent (t½ = 39-100 days) in the following order: thiametoxam > imidacloprid > pirimicarb > chlorantraniliprole. Two major transformation products, desmethyl-formamido pirimicarb and desmethyl pirimicarb, were formed as consequence of dealkylation of the parent compound. Using disturbed soil columns only thiametoxam (93% of the initial amount) and imidacloprid (42% of the initial amount) were recovered from leachates. In the case of pirimicarb and chlorantraniliprole, 74% and 30%, respectively, were recovered from the soil. Thiametoxam and imidacloprid can be catalogued as mobile compounds, while pirimicarb and chlorantraniliprole are classified as immobile according to the screening indices used (GUS and ELI). Leachates containing thiametoxam and imidacloprid were subjected to photocatalytic treatment for 240 min using TiO2/Na2S2O8 with the help of a photochemical reactor equipped with LED lamp. Both compounds had a very fast degradation rate (half-lives ≤ 0.5 min) in deionized water, while their half-lives were 112 min and 178 min, respectively, in leaching water. This implies a strong effect of the water matrix composition, mainly due to organic matter dissolved (quenching). Only traces of thiametoxam urea and hydroxy imidacloprid were detected during the photocatalytic experiment.

Removal Kinetics of Four Leacher Herbicides Through Solar Heterogeneous Photocatalysis as Influenced by Water Matrix Components.

This work focuses on the effect of dissolved substances on the photocatalytic degradation of four herbicides, metribuzin and terbuthylazine (triazine) and chlorotoluron and isoproturon (phenylurea) in three different water matrix (deionized, mineral and leaching water). To study the effect of heterogeneous photocatalysis on their degradation, TiO2 and ZnO were used as photocatalysts in tandem with an oxidant (Na2S2O8). Results show that the addition of both semiconductor materials significantly enhances degradation of the herbicides although in different proportions. Similar effectivity of both photocatalyst, assessed as a function of the mean half-lives calculated, was observed (85 and 87 min for TiO2 and Zn, respectively), while the mean half-life in the photolytic experiment was markedly higher (265 min). The degradation rate was in the order: metribuzin > chlorotoluron ≈ isoproturon > terbuthylazine. A faster degradation was observed in all cases in deionized water as compared to mineral and leaching water indicating that the presence of dissolved salts and organic matter considerably slows down the effectiveness of the treatment. Although after 180 min of treatment, total mineralization was not achieved in mineral and leaching water, this technology considerably reduces the pollutant load in complex water matrices. Therefore, solar heterogeneous photocatalytic processes, especially those involving ZnO and TiO2 as photocatalysts, offers a valuable tool for surface and groundwater remediation, especially in those areas receiving a large number of hours of sunshine per year.

Solar photocatalysis as strategy for on-site reclamation of agro-wastewater polluted with pesticide residues on farms using a modular facility.

One of the consequences of phytosanitary treatments applied to crops is the generation of a great volume of agro-wastewater having pesticide residues. These pollutants can be considered a serious threat to the environment and human health due to their capacity to affect distant areas remaining for a long time after their application. We have assessed the degradation of five pesticides in agro-waste water produced in two farms by the cleaning pesticide containers and phytosanitary treatment equipment used in the farms. For this purpose, a pilot facility was installed in both farms and advanced oxidation treatments were conducted using natural sunlight by means of Na2S2O8 and heterogeneous photocatalysis (TiO2/Na2S2O8). The remaining percentages obtained at the end of the experiments ranged from 5 to 90.1% for chlorantraniliprole, 5 to 82.3% for difenoconazole, 0.02 to 19.1% for metalaxyl, 1.4 to 74.4% for myclobutanil, and 0.3 to 61% for triadimenol. We observed a correlation between the higher remaining percentages and the total initial concentration of pollutant because of other commercial formulations applied in the farms. The results showed that this equipment could be used to eliminate or reduce the presence of pesticide residues in agro-waste water using an innovative facility installed in the farms and a renewable and economical source of energy (sunlight).

Appraisal of water matrix on the removal of fungicide residues by heterogeneous photocatalytic treatment using UV-LED lamp as light source.

In this study, the photocatalytic degradation of four fungicides, myclobutanil, penconazole and difenoconazole (triazole compounds) and boscalid (carboxamide), has been examined in different aqueous matrices (tap water, irrigation water and two WWPT effluents). Experiments were conducted at laboratory scale with different reagents-zinc oxide (ZnO), titanium dioxide (TiO2), sodium persulphate (Na2S2O8) and the combined systems ZnO/Na2S2O8 and TiO2/Na2S2O8-in water exposed to UV-LED irradiation. Previously, the effect of catalyst and oxidant loading on the disappearance kinetics of the different fungicides was assessed to know maximum degradation efficiency. The influence of water matrices and pesticide loading in removal effectiveness has been evaluated. It was observed a greater efficiency in processes conducted using the tandems ZnO/Na2S2O8 and TiO2/Na2S2O8 in irrigation and tap waters. Results showed that UV-LED are a suitable alternative for tackling the removal of organic pollutants in water.

Leaching behaviour appraisal of eight persistent herbicides on a loam soil amended with different composted organic wastes using screening indices.

The addition of organic wastes is a common agronomic practice in some Mediterranean regions to increase soil organic matter. In addition, they consume high amounts of agrochemicals. Hand-packed soil columns were used to evaluate the effect of three different composted organic soil amendments (agro-forestry, agro-industrial and animal manure) on the leachability of eight persistent herbicides. A new leaching index based on the amounts recovered from leachates and referred as Experimental Leaching Index (ELI) is proposed according to the mean annual precipitation in a specific place. This index is compared with others such as Groundwater Ubiquity Score (GUS), Relative Leaching Potential Index (RLPI) and Leachability Index (LIX), which only include degradation (DT50) and sorption (KOC) parameters. According to ELI, metribuzin is very mobile in all cases, while terbuthylazine, chlorotoluron and isoproturon present high leachability only in unamended soil reducing their leaching potential in amended soils. Aclonifen, oxyfluorfen, trifluralin and pendimethalin behave in all cases as immobile (non-leacher) compounds.

Use of Index-Based Screening Models to Evaluate the Leaching of Triclopyr and Fluroxypyr Through a Loam Soil Amended with Vermicompost.

The effect of vermicompost added to a loam soil on the leaching behaviour of two herbicides (triclopyr and fluroxypyr) was examined. Mobility of the herbicides was assessed using disturbed soil columns under laboratory conditions. In both cases, the addition of vermicompost significantly increased the sorption of the compounds. For both, DT50 values were slightly higher in the amended soil, due to the increased adsorption. Rate constants (k) calculated according to pseudo-first order model were significantly lower in the case of triclopyr (very persistent), which led to a much lower degradation rate compared to fluroxypyr (persistent) in both unamended and amended soils. Values calculated for the experimental leaching index (ELI) in unamended and amended soils showed medium and high leachability for fluroxypyr (0.31 and 0.29) and triclopyr (0.72 and 0.70), respectively. Other index-based screening models (GUS, RLPI, LIX) also catalogue both herbicides as potential leachers. Results confirm that triclopyr and fluroxypyr may contaminate groundwater resources.

Electrospun silk fibroin/TiO2 mats. Preparation, characterization and efficiency for the photocatalytic solar treatment of pesticide polluted water.

The photocatalytic properties of silk fibroin (SF) incorporating TiO2 nanoparticles using an electrospinning technique were examined. Electrospun SF/TiO2 mats were successfully prepared and characterized by different techniques (XRD, FE-SEM, XPS, XDS, FTIR and BET). The photocatalytic efficiency of these materials were assessed by their ability to degrade four pesticides (boscalid, hexythiazox, pyraclostrobin and trifloxystrobin) in water exposed to solar irradiation. The effect of catalyst loading on the disappearance kinetics of the different pesticides was studied in order to determine the maximum degradation efficiency. The degradation rate significantly increases upon adding the TiO2. However, no significant differences (p < 0.05) were observed when the TiO2 loading was increased from 25 to 50 mg for most compounds. Thus, SF mats with 25 mg of TiO2 were selected. Therefore, a new and simple approach to produce materials with photocatalytic activity, safety and potential application in the purification of water contaminated by pesticides has been developed.

Solar-driven photocatalytic treatment as sustainable strategy to remove pesticide residues from leaching water.

We have demonstrated the potential leaching of eight compounds, one insecticide (flonicamid) and seven fungicides (myclobutanil, penconazole, boscalid, difenoconazole, trifloxystrobin, pyraclostrobin and fenpyroximate) trough a typical Mediterranean soil (Calcaric regosol). The concentrations found in leaching water were in all cases above the limit set by the EU in groundwater (0.1 µg L-1). For this, the efficiency of different homogeneous (photo-Fenton and photo-Fenton-like) and heterogeneous (ZnO and TiO2) photocatalytic systems was tested in deionized water to choose the most appropriate treatment to remove pesticide residues from leaching water. The efficiency was in the order: ZnO + S2O82- (pH 7) > TiO2+ S2O82- (pH 7) > ZnO (pH 7) > TiO2 (pH 7) > Fe3+ (pH 3) > Fe3+ (pH 5) > Fe2+ (pH 3) > Fe2+ (pH 5). Thus, in the subsequent experiment we focus on the efficacy of solar heterogeneous photocatalysis (ZnO/Na2S2O8 and TiO2/ Na2S2O8) on their removal from leaching water. A fast removal was observed for all pesticides at the end of the photoperiod, noticeably higher in the case of ZnO system, with the exception of flonicamid, a recalcitrant pesticide where the degradation rate only reached about 20% after 240 min of solar exposure. Although the mineralisation of the initial dissolved organic carbon was not complete due to the presence of interfering substances in the leaching water, the conversion rate under ZnO/Na2S2O8 treatment was about 1.3 times higher than using TiO2/Na2S2O8.

Reclamation of agro-wastewater polluted with pesticide residues using sunlight activated persulfate for agricultural reuse.

The removal of 17 pesticides (pymetrozine, flonicamid, imidacloprid, acetamiprid, cymoxanil, thiachloprid, spinosad, chlorantraniliprole, triadimenol, tebuconazole, fluopyram, difenoconazole, cyflufenamid, hexythiazox, spiromesifen, folpet and acrinathrin) found in agro-wastewater from washing of containers and phytosanitary treatments equipment, has been carried out using sodium persulfate (Na2S2O8) at pilot plant scale under natural sunlight. Persulfate is a strong oxidant, inexpensive and environmentally appropriate. However, this oxidant is slow in kinetics under ordinary conditions. Na2S2O8 can be activated by ultraviolet light, generating SO4- radicals, which are also a very strong oxidizing species (E0 = 2.6 V). Previously, preliminary experiments were carried out at laboratory scale using a photoreactor to optimize the Na2S2O8 (300 mg L-1) concentration on the rate constants of the found pesticides. The residual levels of the studied pesticides in agro-wastewater (900 L) were in the range 0.02-1.17 mg L-1 for acrinathrin and fluopyram, respectively. After treatment, nearly complete degradation (>97%) of the parent molecules was achieved although 13% of initial DOC was measured. No significant differences (p < 0.05) were found when comparing grown broccoli using reclaimed and unreclaimed water.

Solar photocatalytic reclamation of agro-waste water polluted with twelve pesticides for agricultural reuse.

This study aims to demonstrate a technically feasible alternative to remove pesticide residues from agro-waste water produced in farms from remnants in containers and treatment tanks, rinse in tanks after treatments, and cleaning of machines and equipment. For this, the photocatalyzed degradation of 12 pesticides commonly used on vegetables, vines, citrus and fruit crops was investigated in aqueous suspensions of TiO2 in tandem with Na2S2O8 at pilot plant scale under natural sunlight in Murcia (SE of Spain) during summer and winter seasons. Previously, preliminary experiments were carried out at laboratory scale using a photoreactor to optimize the photocatalyst (200 mg L-1) and oxidant (250 mg L-1) concentrations on the rate constants of the studied pesticides. The photodegradation of all pesticides can be modelled assuming a pseudo-first-order kinetics. The time needed for disappearance of 90% (DT90) of the studied pesticides, was lower than 4 h in summer in all cases with the exception of cyproconazole (4.9 h), while, cyproconazole (8.9 h), metalaxil (6.1 h) and propyzamide (7.9 h) showed DT90 higher than 6 h in winter. The reaction rate was enhanced 3-fold in summer season, which is directly correlated to the higher accumulated fluence per time received during this season (about a factor of 2.9 higher than in winter). In both cases, the higher and lower degradation rates were obtained for cyprodinil and cyproconazole, respectively. The total fluence to get a 90% reduction (H90) ranged from 4.6 to 5.2 J cm-2 (cyprodinil) to 71.5-76 J cm-2 (cyproconazole).

Solar reclamation of wastewater effluent polluted with bisphenols, phthalates and parabens by photocatalytic treatment with TiO2/Na2S2O8 at pilot plant scale.

Investigations of anthropogenic contaminants in fresh- and wastewater have shown a wide variety of undesirable organic compounds such as Endocrine Disruptors (EDs). As a result, wastewater treatments using innovative technologies to remove those organic compounds are required. In this paper, the photodegradation of six EDs in wastewater at pilot plant scale is reported. The EDs were bisphenol A, bisphenol B, diamyl phthalate, butyl benzylphthalate, methylparaben and ethylparaben. Commercial TiO2 nanopowders (P25, Alfa Aesar and Kronos vlp 7000) were used as photocatalysts. The operating variables (type and loading catalyst, effect of electron acceptor and pH) were previously optimized under laboratory conditions. The results show that the use of TiO2 alongside an electron acceptor like Na2S2O8 strongly enhances the degradation rate of the studied compounds compared with photolytic tests, especially P25. The oxidation rates of the EDs at pilot plant scale were calculated following the disappearance of the target compound as a function of fluence (H). The ED degradation followed a pseudo-first order kinetics in all cases. In our experimental conditions, the half-fluence (H50) varied from 79 to 173 J cm-2 (photolytic test), 10-117 J cm-2 (TiO2 vlp 7000) and 3-58 J cm-2 (TiO2 P25), for bisphenol B and butyl benzylphthalate, respectively. It is concluded that solar photocatalysis using the tandem TiO2/Na2S2O8 can be considered as an environmental-friendly tool for water detoxification and a sustainable technology for environmental remediation, especially in the Mediterranean Basin, where many places receive more than 3000 h of sunshine per year. Although the cost depends on the nature of the pollutant, the treatment cost was estimate to be about 150 € m-3 for photocatalytic treatment with TiO2 P25.

Photocatalytic oxidation of six endocrine disruptor chemicals in wastewater using ZnO at pilot plant scale under natural sunlight.

Endocrine disruptors (EDs) are xenobiotics that interfere with the synthesis, secretion, transport, binding, action, and elimination of the natural hormones. In this paper, the photodegradation of six EDs in municipal wastewater treatment plant effluents at pilot plant scale is reported. The EDs were bisphenol A, bisphenol B, diamyl phthalate, butyl benzylphthalate, methyl p-hydroxybenzoate, and ethyl 4-hydroxybenzoate. ZnO as photocatalyst in tandem with Na2S2O8 as electron acceptor under natural sunlight were used. The process was previously optimized under laboratory conditions through a photoreactor under artificial UVA irradiation studying the role of some key operating parameters (catalyst loading, effect of electron acceptor, and pH). Results carried out at pilot plant scale show that addition of ZnO in tandem with Na2S2O8 strongly enhances degradation rates compared with photolytic test. At the end of the irradiation time (240 min), the remaining amounts of EDs ranged from 24% (butyl benzylphthalate) to 0% (< LOQ bisphenol B). The degradation rates were in the order: bisphenols > parabens > phthalates. After the photoperiod, 83% of the initial dissolved organic carbon was removed and toxicity decreased to acceptable values (11% inhibition to Vibrio fisheri). The photodegradation process was found to follow pseudo-first-order kinetic model with DT50 ranging from 5 min (bisphenol B) to 102 min (butyl benzylphthalate). Thereby, photocatalytic oxidation using ZnO is an area of environmental interest for the treatment of polluted water, particularly relevant for Mediterranean countries, where solar irradiation is highly available.

Evaluation of the Leaching Potential of Anthranilamide Insecticides Through the Soil.

The mobility of two relatively new antranilic diamide insecticides, cyanantraniliprole (CY) and cholantraniliprole (CH) in soil was examined, by means of disturbed columns loaded with a typical semiarid Mediterranean soil (Calcaric fluvisol) under laboratory conditions. Both insecticides appeared in leachates, with 52% of CY and 41% of CH of the initial mass added (1 µg g-1) present. For CY, 21% and 19% were recovered from the upper and bottom layers of the soil, respectively, while for CH, 33% and 22% were recovered from the upper and bottom layers respectively. Based on the calculated half-lives (29 and 27 days for CY and CH, respectively) and their log K OC (about 2.5 for both), the calculated Groundwater Ubiquity Score (GUS) index was higher than 5 for both, indicating they have the potential to leach. Two transformation products, C13H9Cl2N2O (IN-ECD73) and C19H12BrClN6O (IN-J9Z38) corresponding to the degradation of CH and CY, respectively were also identified and detected in leachates and soil.

Trial of solar heating methods (solarization and biosolarization) to reduce persistence of neonicotinoid and diamide insecticides in a semiarid Mediterranean soil.

This paper reports the use of solar heating techniques, solarization (S) and biosolarization (BS) as a strategy for the environmental restoration of soils containing neonicotinoid, acetamiprid (AC), imidacloprid (IM) and thiamethoxam (TH), and diamide, chlorantraniliprole (CL) and flubendiamide (FB) insecticide residues. For this, a semiarid Mediterranean soil (Haplic calcisol) was covered with low-density polyethylene (LDPE) during the hot season, to raise the maximal soil temperatures. Compost from sheep manure (CSM), meat-processing waste (MPW) and sugar beet vinasse (SBV) were used as organic wastes. The results showed that both S and BS increase insecticide disappearance rates compared with the non-disinfected soil, the increase in soil temperature and added organic matter playing a key role. The dissipation rates of TH and AC in soil were satisfactorily described by first-order (monophasic) kinetics, while IM, CL and FB showed a deviation from exponential behaviour. For them, the best results were obtained applying biphasic kinetics with a rapid initial degradation followed by a slower decline of their residues. The findings suggest that S and BS (especially using MPW) can be considered as a valuable tool for enhancing the detoxification of soils polluted with these insecticides.

Enhanced degradation of spiro-insecticides and their leacher enol derivatives in soil by solarization and biosolarization techniques.

The leaching potential of three insecticides (spirodiclofen, spiromesifen, and spirotetramat) was assessed using disturbed soil columns. Small quantities of spirodiclofen and spiromesifen were detected in leachate fraction, while spirotetramat residues were not found in the leachates. In addition, the transformation products (enol derivatives) are relatively more mobile than the parent compounds and may leach into groundwater. Moreover, the use of disinfection soil techniques (solarization and biosolarization) to enhance their degradation rates in soil was investigated. The results show that both practices achieved a reduction in the number of juvenile nematodes, enhancing in a parallel way degradation rates of the insecticides and their enol derivatives as compared with the non-disinfected soil. This behavior can be mainly attributed to the increase in soil temperature and changes in microbial activity. All insecticides showed similar behavior under solarization and biosolarization conditions. As a consequence, both agronomic techniques could be considered as suitable strategies for detoxification of soils polluted with the studied pesticides.