Uptake, accumulation and impact of antiretroviral and antiviral pharmaceutical compounds in lettuce

Plant Uptake of Persistent and Mobile Chemicals in Rocket (Eruca sativa)─A Greenhouse Study on Agricultural Wastewater Reuse

With increasing water stress, agricultural wastewater reuse is becoming more prevalent worldwide. In this context, persistent and mobile (PM) chemicals may be especially relevant, yet data on their uptake by plants are still scarce. This study investigates the uptake of 61 PM chemicals by and distribution in rocket (Eruca sativa) in pot experiments from spiked water and treated municipal wastewater. The relative uptake (RU; share of theoretical maximum uptake) into rocket exceeded 10% for 18 PM chemicals, among others, perfluoropropionic acid (72% RU), trifluoroacetic acid (67%), and tetrafluoroborate (40%). The median plant uptake (p ≤ 0.05) and translocation factor (p < 0.0001) were significantly higher for PM chemicals than reported for less polar chemicals into leafy greens from literature. Irrigation of rocket with reclaimed municipal wastewater resulted in the accumulation of 23 analytes. However, a toxicological threshold of concern approach showed that no critical exposure is reached for these compounds at normal consumption levels. Comparing wastewater treatment plant effluent concentrations with plant uptake data led to a prioritization of PM chemicals, which might be especially relevant for agricultural wastewater reuse and should be considered in risk assessment.

Remediation strategies of antiretroviral drugs in the aquatic environment: current trend and future perspectives

The presence of antiretroviral drugs (ARVs) in the aquatic environment highlights the inadequacy of traditional wastewater treatment plants in their remediation. Moreover, the fate and associated human and ecotoxicological impact of those compounds are not well established. In fact, research focusing on effective alternative treatment solutions still seems lacking. However, a growing interest in remediation techniques for pharmaceutical residues, including ARVs in wastewater, has been noticed recently. The main objective of this review is to share updated information and literature on the recent advances in wastewater treatment strategies to eliminate traces of ARVs from wastewater. Research gaps and possible ways forward for further research in the development of effective alternative treatments are well narrated in the current review. Furthermore, useful information can be derived from the highlighted biodegradation mechanisms to better understand the environmental fate of these compounds. An overview of different treatment methods is given, with particular emphasis on the removal efficiencies, reaction kinetics, degradation mechanisms, and process limitations. A summary of the environmental occurrence of ARVs is provided, as well as the status of the global HIV prevalence and antiretroviral therapy.

Ecotoxicological bioassays with terrestrial plants: a holistic view of standards, guidelines, and protocols

Terrestrial and aquatic ecosystems face various chemicals that might induce acute and/or long-term harm. To assess these impacts, ecotoxicological bioassays are essential. However, bioassays using animals, particularly mammals, are costly, time-consuming, and raise ethical concerns. In this context, terrestrial plants emerge as a viable alternative to conventional assays. Thus, the aim of this review was to address the history and evolution of plant bioassays, highlighting the main regulations, guidelines, and protocols governing the use of terrestrial plants in ecotoxicological tests. Initially, plant bioassays were employed to assess the cytogenotoxic effects of chemicals, gaining prominence with the GENE-TOX program in the 80s. Subsequently, plants were used in allelopathy bioassays and in studies aimed to examine the ecotoxicity of pesticides in soil. Currently, ecotoxicological bioassays with plants are regulated by specific standards, such as ASTM E1963-22, EPA 600/3-88/029, EPS 1/RM/45, ISO 11269-1, ISO 11269-2, ISO 17126, ISO 18763, ISO 29200, ISO 22030, OECD-208, OECD-227, OCSPP 850.4100, OCSPP 850.4230, OCSPP 850.4800 and OPPTS 850.4200. The existing protocols standardize bioassays in greenhouse and lab environments, and the duration of the tests varies from hours to months. The main ecotoxicological parameters to be analyzed after exposure include germination percentage, survival rate, root length, aerial part length, fresh mass of exposed plants, and phytotoxicity symptoms. In addition, the absorption rate of substances and genotoxic and mutagenic effects might also be assessed. Therefore, data in this review demonstrate that terrestrial plants represent an important tool in the analysis of environmental risks associated with chemicals and might serve as crucial allies in modern ecotoxicology.

Assessing Lettuce Exposure to a Multipharmaceutical Mixture under Hydroponic Conditions: Findings through LC-ESI-TQ Analysis and Ecotoxicological Assessments

The escalating global water scarcity demands innovative solutions, one of which is hydroponic vegetable cultivation systems that increasingly use reclaimed wastewater. Nevertheless, even treated wastewater may still harbor various emerging organic contaminants, including pharmaceuticals. This study aimed to comprehensively assess the impact of pharmaceuticals, focusing on bioconcentration factors (BCFs), translocation factors (TFs), pharmaceutical persistence in aqueous environment, ecotoxicological end points, and associated environmental and health risks. Lettuce (Lactuca sativa) was cultivated hydroponically throughout its entire growth cycle, exposed to seven distinct concentration levels of contaminants ranging from 0 to 500 μg·L-1 over a 35-day period. The findings revealed a diverse range of BCFs (2.3 to 880 L·kg-1) and TFs (0.019-1.48), suggesting a high potential of pharmaceutical uptake and translocation by L. sativa. The degradation of 20 pharmaceuticals within the water-lettuce system followed first-order degradation kinetics. Substantial ecotoxicological effects on L. sativa were observed, including increased mortality, alterations in root morphology and length, and changes in biomass weight (p < 0.05). Furthermore, the estimated daily intake of pharmaceuticals through L. sativa consumption suggested considerable health risks, even if lettuce would be one of the many vegetables consumed. It is hypothetical, as the values were calculated. Moreover, this study assessed the environmental risk associated with the emergence of antimicrobial resistance (AMR) in aquatic environments, revealing a significantly high risk of AMR emergence. In conclusion, these findings emphasize the multifaceted challenges posed by pharmaceutical contamination in aquatic environments and the necessity of proactive measures to mitigate associated risks to both environmental and human health.

Pharmaceutical metabolite identification in lettuce (Lactuca sativa) and earthworms (Eisenia fetida) using liquid chromatography coupled to high-resolution mass spectrometry and in silico spectral library

Pharmaceuticals released into the aquatic and soil environments can be absorbed by plants and soil organisms, potentially leading to the formation of unknown metabolites that may negatively affect these organisms or contaminate the food chain. The aim of this study was to identify pharmaceutical metabolites through a triplet approach for metabolite structure prediction (software-based predictions, literature review, and known common metabolic pathways), followed by generating in silico mass spectral libraries and applying various mass spectrometry modes for untargeted LC-qTOF analysis. Therefore, Eisenia fetida and Lactuca sativa were exposed to a pharmaceutical mixture (atenolol, enrofloxacin, erythromycin, ketoprofen, sulfametoxazole, tetracycline) under hydroponic and soil conditions at environmentally relevant concentrations. Samples collected at different time points were extracted using QuEChERS and analyzed with LC-qTOF in data-dependent (DDA) and data-independent (DIA) acquisition modes, applying both positive and negative electrospray ionization. The triplet approach for metabolite structure prediction yielded a total of 3762 pharmaceutical metabolites, and an in silico mass spectral library was created based on these predicted metabolites. This approach resulted in the identification of 26 statistically significant metabolites (p < 0.05), with DDA + and DDA - outperforming DIA modes by successfully detecting 56/67 sample type:metabolite combinations. Lettuce roots had the highest metabolite count (26), followed by leaves (6) and earthworms (2). Despite the lower metabolite count, earthworms showed the highest peak intensities, closely followed by roots, with leaves displaying the lowest intensities. Common metabolic reactions observed included hydroxylation, decarboxylation, acetylation, and glucosidation, with ketoprofen-related metabolites being the most prevalent, totaling 12 distinct metabolites. In conclusion, we developed a high-throughput workflow combining open-source software with LC-HRMS for identifying unknown metabolites across various sample types.

Assessing Lettuce Exposure to a Multi-Pharmaceutical Mixture in Soil: Insights from LC-ESI-TQ Analysis and the Impact of Biochar on Pharmaceutical Bioavailability

Agricultural practices introduce pharmaceutical (PhAC) residues into the terrestrial environment, potentially endangering agricultural crops and human health. This study aimed to evaluate various aspects related to the presence of pharmaceuticals in the lettuce-soil system, including bioconcentration factors (BCFs), translocation factors (TFs), ecotoxicological effects, the influence of biochar on the PhAC bioavailability, persistence in soil, and associated environmental and health risks. Lettuce (Lactuca sativa L.) was exposed to a mixture of 25 PhACs in two scenarios: initially contaminated soil (ranging from 0 to 10,000 ng·g-1) and soil irrigated with contaminated water (ranging from 0 to 1000 μg·L-1) over a 28-day period. The findings revealed a diverse range of BCFs (0.068-3.7) and TFs (0.032-0.58), indicating the uptake and translocation potential of pharmaceuticals by lettuce. Significant ecotoxicological effects on L. sativa, including weight change and increased mortality, were observed (p < 0.05). Interestingly, biochar did not significantly affect PhAC uptake by L. sativa (p > 0.05), while it significantly influenced the soil degradation kinetics of 12 PhACs (p < 0.05). Additionally, the estimated daily intake of PhACs through the consumption of L. sativa suggested negligible health risks, although concerns arose regarding the potential health risks if other vegetable sources were similarly contaminated with trace residues. Furthermore, this study evaluated the environmental risk associated with the emergence of antimicrobial resistance (AMR) in soil, as medium to high. In conclusion, these findings highlight the multifaceted challenges posed by pharmaceutical contamination in agricultural environments and emphasize the importance of proactive measures to mitigate the associated risks to both environmental and human health.

Alternating water sources to minimize contaminant accumulation in food plants from treated wastewater irrigation

The use of treated wastewater (TWW) for agricultural irrigation is a critical measure in advancing sustainable water management and agricultural production. However, TWW irrigation in agriculture serves as a conduit to introduce many contaminants of emerging concern (CECs) into the soil-plant-food continuum, posing potential environmental and human health risks. Currently, there are few practical options to mitigate the potential risk while promoting the safe reuse of TWW. In this greenhouse study, the accumulation of 11 commonly occurring CECs was evaluated in three vegetables (radish, lettuce, and tomato) subjected to two different irrigation schemes: whole-season irrigation with CEC-spiked water (FULL), and half-season irrigation with CEC-spiked water, followed by irrigation with clean water for the remaining season (HALF). Significant decreases (57.0-99.8 %, p < 0.05) in the accumulation of meprobamate, carbamazepine, PFBS, PFBA, and PFHxA in edible tissues were found for the HALF treatment with the alternating irrigation scheme. The CEC accumulation reduction was attributed to reduced chemical input, soil degradation, plant metabolism, and plant growth dilution. The structural equation modeling showed that this mitigation strategy was particularly effective for CECs with a high bioaccumulation potential and short half-life in soil, while less effective for those that are more persistent. The study findings demonstrate the effectiveness of this simple and on-farm applicable management strategy that can be used to minimize the potential contamination of food crops from the use of TWW and other marginal water sources in agriculture, while promoting safe reuse and contributing to environmental sustainability.

Integrated study of antiretroviral drug adsorption onto calcined layered double hydroxide clay: experimental and computational analysis

This study focused on the efficacy of a calcined layered double hydroxide (CLDH) clay in adsorbing two antiretroviral drugs (ARVDs), namely efavirenz (EFV) and nevirapine (NVP), from wastewater. The clay was synthesized using the co-precipitation method, followed by subsequent calcination in a muffle furnace at 500 °C for 4 h. The neat and calcined clay samples were subjected to various characterization techniques to elucidate their physical and chemical properties. Response surface modelling (RSM) was used to evaluate the interactions between the solution's initial pH, adsorbent loading, reaction temperature, and initial pollutant concentration. Additionally, the adsorption kinetics, thermodynamics, and reusability of the adsorbent were evaluated. The results demonstrated that NVP exhibited a faster adsorption rate than EFV, with both reaching equilibrium within 20-24 h. The pseudo-second order (PSO) model provided a good fit for the kinetics data. Thermodynamics analysis revealed that the adsorption process was spontaneous and exothermic, predominantly governed by physisorption interactions. The adsorption isotherms followed the Freundlich model, and the maximum adsorption capacities for EFV and NVP were established to be 2.73 mg/g and 2.93 mg/g, respectively. Evaluation of the adsorption mechanism through computational analysis demonstrated that both NVP and EFV formed stable complexes with CLDH, with NVP exhibiting a higher affinity. The associated adsorption energies were established to be -731.78 kcal/mol for NVP and -512.6 kcal/mol for EFV. Visualized non-covalent interaction (NCI) graphs indicated that hydrogen bonding played a significant role in ARVDs-CLDH interactions, further emphasizing physisorption as the dominant adsorption mechanism.

Insight into the uptake, translocation, metabolism, dissipation and risk assessment of tolfenpyrad in romaine and edible amaranth grown in hydroponic conditions

Tolfenpyrad is an alternative to highly water-soluble and ecotoxic insecticides that is widely used in China. It is absorbed and accumulates in vegetables, leading to potential public-health hazards. A systematic study of the fate of tolfenpyrad is necessary for proper application and food safety. Herein, we report on the uptake, translocation, metabolism, dissipation, and dietary risks of tolfenpyrad in hydroponic romaine and amaranth plants. Roots easily absorbed and accumulated tolfenpyrad, although transport was moderate in both vegetables. Basipetal translocation of tolfenpyrad occurred in romaine but not in edible amaranth, owing to differences in specific transport behaviour in each case. Six metabolites and three pathways were proposed. Tolfenpyrad affected antioxidant enzyme activities in different parts of the two vegetables. Tolfenpyrad dissipation proceeded swiftly, entailing an acceptable risk to humans. Our results provide information on the distribution and transport of tolfenpyrad, as well as on the safety in using it on vegetables.

Tracing COVID-19 drugs in the environment: Are we focusing on the right environmental compartment?

The Coronavirus Disease 2019 (COVID-19) pandemic led to over 770 million confirmed cases, straining public healthcare systems and necessitating extensive and prolonged use of synthetic chemical drugs around the globe for medical treatment and symptom relief. Concerns have arisen regarding the massive release of active pharmaceutical ingredients (APIs) and their metabolites into the environment, particularly through domestic sewage. While discussions surrounding this issue have primarily centered on their discharge into aquatic environments, particularly through treated effluent from municipal wastewater treatment plants (WWTPs), one often overlooked aspect is the terrestrial environment as a significant receptor of pharmaceutical-laden waste. This occurs through the disposal of sewage sludge, for instance, by applying biosolids to land or non-compliant disposal of sewage sludge, in addition to the routine disposal of expired and unused medications in municipal solid wastes. In this article, we surveyed sixteen approved pharmaceuticals for treating COVID-19 and bacterial co-infections, along with their primary metabolites. For this, we delved into their physiochemical properties, ecological toxicities, environmental persistence, and fate within municipal WWTPs. Emphasis was given on lipophilic substances with log Kow >3.0, which are more likely to be found in sewage sludge at significant factions (25.2%-75.0%) of their inputs in raw sewage and subsequently enter the terrestrial environment through land application of biosolids, e.g., 43% in the United States and as high as 96% in Ireland or non-compliant practices of sewage sludge disposal in developing communities, such as open dumping and land application without prior anaerobic digestion. The available evidence underscores the importance of adequately treating and disposing of sewage sludge before its final disposal or land application in an epidemic or pandemic scenario, as mismanaged sewage sludge could be a significant vector for releasing pharmaceutical compounds and their metabolites into the terrestrial environment.

Low-dose chemical stimulation and pest resistance threaten global crop production

Pesticide resistance increases and threatens crop production sustainability. Chemical contamination contributes to the development of pest resistance to pesticides, in part by causing stimulatory effects on pests at low sub-toxic doses and facilitating the spread of resistance genes. This article discusses hormesis and low-dose biological stimulation and their relevance to crop pest resistance. It highlights that a holistic approach is needed to tackle pest resistance to pesticides and reduce imbalance in accessing food and improving food security in accordance with the UN's Sustainable Development Goals. Among others, the effects of sub-toxic doses of pesticides should be considered when assessing the impact of synthetic and natural pesticides, while the promotion of alternative agronomical practices is needed to decrease the use of agrochemicals. Potential alternative solutions include camo-cropping, exogenous application of phytochemicals that are pest-suppressing or -repelling and/or attractive to carnivorous arthropods and other pest natural enemies, and nano-technological innovations. Moreover, to facilitate tackling of pesticide resistance in poorer countries, less technology-demanding and low-cost practices are needed. These include mixed cropping systems, diversification of cultures, use of 'push-pull cropping', incorporation of flower strips into cultivations, modification of microenvironment, and application of beneficial microorganisms and insects. However, there are still numerous open questions, and more research is needed to address the ecological and environmental effects of many of these potential solutions, with special reference to trophic webs.

Uptake and Enantiomeric Selectivity of β-Blockers in Lettuce (Lactuca sativa L.) and Tomato (Lycopersicon esculentum M.) in Soil-Pot Culture

The uptake and translocation of β-blockers in lettuce (Lactuca sativa L.) and tomato (Lycopersicon esculentum M.) were investigated by carrying out a 70-day soil-pot cultivation. The root uptake parameters of β-blockers in lettuce decreased in the order of atenolol (ATE) > sotalol (SOT) > propranolol (PRO) with root bioconcentration factors (BCFsroot/soil) of 0.158, 0.136, and 0.096, respectively, which were positively correlated with their water solubility. The BCFroot/soil of β-blockers in tomato was higher than those in lettuce. ATE and PRO were prone to migrate to the aerial parts of tomato with translocation factors of 3.31 and 4.11, respectively. In tomato fruits, the enantiomeric profile of PRO and ATE shifted to that dominated by the more toxic enantiomer, i.e., (S)-PRO and (R)-ATE. The enantiomeric selectivity of β-blockers in the edible parts of lettuce and tomato indicated the potential ecotoxicity of these pharmaceuticals for plants and the human exposure risk via vegetable intake.

Selective accumulation of pharmaceutical residues from 6 different soils by plants: a comparative study on onion, radish, and spinach

The accumulation of six pharmaceuticals of different therapeutic uses has been thoroughly investigated and compared between onion, spinach, and radish plants grown in six soil types. While neutral molecules (e.g., carbamazepine (CAR) and some of its metabolites) were efficiently accumulated and easily translocated to the plant leaves (onion > radish > spinach), the same for ionic (both anionic and cationic) molecules seems to be minor to moderate. The maximum accumulation of CAR crosses 38,000 (onion), 42,000 (radish), and 7000 (spinach) ng g-1 (dry weight) respectively, in which the most majority of them happened within the plant leaves. Among the metabolites, the accumulation of carbamazepine 10,11-epoxide (EPC - a primary CAR metabolite) was approximately 19,000 (onion), 7000 (radish), and 6000 (spinach) ng g-1 (dry weight) respectively. This trend was considerably similar even when all these pharmaceuticals applied together. The accumulation of most other molecules (e.g., citalopram, clindamycin, clindamycin sulfoxide, fexofenadine, irbesartan, and sulfamethoxazole) was restricted to plant roots, except for certain cases (e.g., clindamycin and clindamycin sulfoxide in onion leaves). Our results clearly demonstrated the potential role of this accumulation process on the entrance of pharmaceuticals/metabolites into the food chain, which eventually becomes a threat to associated living biota.

Case study on antiretroviral drugs uptake from soil irrigated with contaminated water: Bio-accumulation and bio-translocation to roots, stem, leaves, and fruits

This study aimed to evaluate the potential of uptake of the commonly used antiretroviral drugs (ARVDs) in South Africa (abacavir, nevirapine, and efavirenz) by vegetable plants (beetroot, spinach, and tomato) from contaminated soil culture. The study results showed that all the studied vegetables have the potential to take up abacavir, nevirapine, and efavirenz from contaminated soil, be absorbed by the root, and translocate them to the aerial part of the plants. The total percentage of ARVDs found in the individual plant was mainly attributed to abacavir which contributed 53% in beetroot and 48% in spinach, while efavirenz (42%) was the main contributor in tomato. Abacavir was found at high concentrations to a maximum of 40.21 μg/kg in the spinach root, 18.43 μg/kg in the spinach stem, and 6.77 μg/kg in the spinach soil, while efavirenz was the highest concentrations, up to 35.44 μg/kg in tomato leaves and 8.86 μg/kg in tomato fruits. Spinach roots accumulated more ARVDs than beetroot and tomato however, the concentrations were not statistically different. Hydrophobicity was the main effect on the linearity, accumulation, and translocation of ARVDs. This study advances knowledge on the fate of ARVDs in agroecosystems, particularly in plant root - ARVD interaction and the resulting potentially toxic effects on plants. These results suggest that the quality of water used for crop irrigation needs to be assessed prior to irrigation to avoid vegetable plant pollution as contaminated water results in the contaminants uptake by plants. This may lead to the transfer of pollutants to the edible crops parts of and thus be unintentionally consumed by humans. More studies need to be continuously conducted to evaluate ARVDs bioaccumulation and their mechanism of uptake by other vegetables. The use of the pot-plant system can be recommended because it closely relates to the agricultural world.

Bioaccumulation of abacavir and efavirenz in Rhinella arenarum tadpoles after exposure to environmentally relevant concentrations

Antiretrovirals are pharmaceuticals used in the treatment of the human immunodeficiency virus; they are contaminants of emerging concern that have received considerable attention in recent decades due to their potential negative environmental effects. Data on the bioaccumulation and possible environmental risks posed by these drugs to aquatic organisms are very scarce. Therefore, the aim of this study was to evaluate the bioaccumulation of abacavir and efavirenz in Rhinella arenarum tadpoles subjected to acute static toxicity tests (96 h) at environmentally relevant concentrations. The analytical procedure consisted of the development and optimization of a method involving ultra-high performance liquid chromatography with tandem mass spectrometry detection. The instrumental conditions, optimized by design of experiments using the response surface methodology, yielded limits of detection of 0.3 μg L^-1 for abacavir and 0.9 μg L^-1 for efavirenz; and limits of quantification of 1.9 μg L^-1 for abacavir and 5.6 μg L^-1 for efavirenz. Subsequently, the bioaccumulation of the pharmaceutical drugs in tadpoles was evaluated at three exposure concentrations. Efavirenz displayed the highest bioaccumulation levels. This study shows the bioaccumulation potential of abacavir and efavirenz in amphibian tadpoles at exposure concentrations similar to those already detected in the environment, indicating an ecological risk for R. arenarum and probably other aquatic organisms exposed to these drugs in water bodies.

A critical review on environmental presence of pharmaceutical drugs tested for the covid-19 treatment

On March 11, 2020, the World Health Organization (WHO) declared COVID-19 a pandemic. The outbreak caused a worldwide impact, becoming a health threat to the general population and its professionals. To date, there are no specific antiviral treatments or vaccines for the COVID-19 infection, however, some drugs are being clinically tested. The use of these drugs on large scale raises great concern about their imminent environmental risk, since the elimination of these compounds by feces and urine associated with the inefficiency of sewage treatment plants in their removal can result in their persistence in the environment, putting in risk the health of humans and of other species. Thus, the goal of this work was to conduct a review of other studies that evaluated the presence of the drugs chloroquine, hydroxychloroquine, azithromycin, ivermectin, dexamethasone, remdesivir, favipiravir and some HIV antivirals in the environment. The research indicated the presence of these drugs in the environment in different regions, with concentration data that could serve as a basis for further comparative studies following the pandemic.

SARS-CoV-2 and other main pathogenic microorganisms in the environment: Situation in Galicia and Spain

In the context of the current COVID-19 pandemic, and mostly taking a broad perspective, it is clearly relevant to study environmental factors that could affect eventual future outbreaks due to coronaviruses and/or other pathogenic microorganisms. In view of that, the authors of this manuscript review the situation of SARS-CoV-2 and other main pathogenic microorganisms in the environment, focusing on Galicia and Spain. Overall, in addition to showing local data, it is put in evidence that, summed to all efforts being carried out to treat/control this and any other eventual future epidemic diseases, both at local and global levels, a deep attention should be paid to ecological/environmental aspects that have effects on the planet, its ecosystems and their relations/associations with the probability of spreading of eventual future pandemics.