Uptake and bioaccumulation of three widely prescribed pharmaceutically active compounds in tomato fruits and mediated effects on fruit quality attributes

Occurrence of pharmaceuticals in rice (Oryza sativa L.) plant through wastewater irrigation

The present investigation focuses on the identification of popular PhACs in roots, leaves and rice grains, which are cultivated in soil irrigated with waters and wastewater. The present study reveals the presence of PhACs in rice grains from different brands which are available in the current market, which has thus motivated these experiments. The rice plants were cultivated in garden containers and irrigated with three different water sources. All PhAC compounds were recovered within an 89-111 % range using the extraction technique, reproducibility, and sensitivity (LOQ <25 µg/g). Further, PhAC compounds were identified using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QqTOF-MS). Interestingly, several PhAC compounds were detected in rice grains, aligning with hypotheses and findings from published literature. A total of ten (10) PhACs were found in the root, leaf, and rice grain of the 20 popular PhACs that were targeted. The annual exposure and medical dose equivalent for individual PhACs was negligible. According to our knowledge, this study is the first to show the accumulation of several categories (cocktail) of PhACs in rice grains and show the approximate human health risk assessment by its consumption. The study's results provide valuable insights for researchers, policymakers, and agricultural practitioners working on sustainable agriculture and public health.

Uptake and translocation of pharmaceutically active compounds by olive tree (Olea europaea L.) irrigated with treated municipal wastewater

Introduction

The use of treated municipal wastewater (TWW) represents a relevant opportunity for irrigation of agricultural crops in semi-arid regions to counter the increasing water scarcity. Pharmaceutically active compounds (PhACs) are often detected in treated wastewater, posing a risk to humans and the environment. PhACs can accumulate in soils and translocate into different plant tissues, reaching, in some cases, edible organs and entering the food chain.

Methods

This study evaluated the uptake and translocation processes of 10 PhACs by olive trees irrigated with TWW, investigating their accumulation in different plant organs. The experiment was conducted in southern Italy, in 2-year-old plants irrigated with three different types of water: freshwater (FW), TWW spiked with 10 PhACs at a concentration of 200 µg L-1 (1× TWW), and at a triple dose (3× TWW), from July to October 2021. The concentration of PhACs in soil and plant organs was assessed, collecting samples of root, stem, shoot, leaf, fruit, and kernel at 0 (T0), 50 (T1), and 107 (T2) days of irrigation. PhACs extraction from soil and plant organs was carried out using the QuEChERS method, and their concentrations were determined by high-resolution mass spectrometry coupled with liquid chromatography.

Results

Results of uptake factors (UF) showed a different behavior between compounds according to their physicochemical properties, highlighting PhACs accumulation and translocation in different plant organs (also edible part) in 1× TWW and 3× TWW compared to FW. Two PhACs, carbamazepine and fluconazole, showed interactions with the soil-plant system, translocating also in the aerial part of the plant, with a translocation factor (TF) greater than 1, which indicates high root-to-leaf translocation.

Discussion

Findings highlight that only few PhACs among the selected compounds can be uptaken by woody plants and accumulated in edible parts at low concentration. No effects of PhACs exposure on plant growth have been detected. Despite the attention to be paid to the few compounds that translocate into edible organs, these results are promising for adapting wastewater irrigation in crops. Increasing knowledge about PhACs behavior in woody plants can be important for developing optimized wastewater irrigation and soil management strategies to reduce PhACs accumulation and translocation in plants.

Uptake of Pharmaceuticals by Crops: A Systematic Review and Meta-analysis

Studies on the uptake of pharmaceuticals from soils into crops were first conducted in the 2000s. Since then a wealth of such data has been generated, but to the best of our knowledge, these studies have not been systematically reviewed. We present a quantitative, systematic review of empirical data on the uptake of pharmaceuticals into crops. We developed a custom-made relational database on plant uptake of pharmaceuticals that contained details of the experimental design and associated results from 150 articles, spanning 173 pharmaceuticals, 78 study crops, and 8048 unique measurements. Analysis of the data in the database showed clear trends in experimental design, with lettuce being the most studied crop and carbamazepine and sulfamethoxazole being the most studied pharmaceuticals. Pharmaceutical properties were found to create the greatest range in uptake concentrations of any single variable studied. Uptake concentrations were also found to vary between crops, with relatively high uptake concentrations identified in cress, lettuce, rice, and courgette crops. An understanding of the influence of soil properties on pharmaceutical uptake was limited by a lack of information on key soil properties across the published literature. The data comparisons were inhibited by differences in quality of the different studies. Moving forward, a framework for best practice in this field is needed to maximize the value and further applications of the data produced. Environ Toxicol Chem 2023;42:2091-2104. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

The fate of sulfonamides in microenvironments of rape and hot pepper rhizosphere soil system

Sulfonamides (SAs) in agricultural soils can be degraded in rhizosphere, but can also be taken up by vegetables, which thereby poses human health and ecological risks. A glasshouse experiment was conducted using multi-interlayer rhizoboxes to investigate the fate of three SAs in rape and hot pepper rhizosphere soil systems to examine the relationship between the accumulation and their physicochemical processes. SAs mainly entered pepper shoots in which the accumulation ranged from 0.40 to 30.64 mg kg-1, while SAs were found at high levels in rape roots ranged from 3.01 to 16.62 mg kg-1. The BCFpepper shoot exhibited a strong positive linear relationship with log Dow, while such relationship was not observed between other bioconcentration factors (BCFs) and log Dow. Other than lipophilicity, the dissociation of SAs may also influence the uptake and translocation process. Larger TF and positive correlation with log Dow indicate preferential translocation of pepper SAs. There was a significant (p < 0.05) dissipation gradient of SAs observed away from the vegetable roots. In addition, pepper could uptake more SAs under solo exposure, while rape accumulated more SAs under combined exposure. When SAs applied in mixture, competition between SAs might occur to influence the translocation and dissipation patterns of SAs.

Chelating agents supported solar photo-Fenton and sunlight/H2O2 processes for pharmaceuticals removal and resistant pathogens inactivation in quaternary treatment for urban wastewater reuse

In this work, Fe³⁺-iminodisuccinic acid (Fe:IDS) based solar photo Fenton (SPF), an Italian patented method, was investigated in quaternary treatment of real urban wastewater and compared to Fe³⁺-ethylenediamine-N,N'-disuccinic acid (Fe:EDDS) for the first time. Three pharmaceuticals (PCs) (sulfamethoxazole, carbamazepine and trimethoprim) and four pathogens (Escherichia coli, somatic and F-plus coliphages, Clostridium perfringens, consistently with the new EU regulation for wastewater reuse (2020/741)), were chosen as target pollutants. SPF with Fe:EDDS was more effective in PCs removal (80%, 10 kJ L^-1) than the SPF with Fe:IDS (58%), possibly due to the higher capability of generating hydroxyl radicals. On the contrary, Fe:IDS was more effective (4.3 log inactivation for E. coli) than Fe:EDDS (1.9 log) in pathogens inactivation, possibly due to a lower iron precipitation and turbidity which finally promoted an improved intracellular photo-Fenton mechanism. Fe:L based SPF was subsequently coupled to sunlight/H₂O₂. Interestingly, while its combination with Fe:EDDS based SPF slightly increased disinfectant efficacy (2.3 vs 1.9 log inactivation for E. coli), the combination with Fe:IDS decreased inactivation efficiency (3.4 vs 4.3 log reduction). In conclusion, due to the good compromise between PCs removal and disinfection efficiency, Fe:IDS SPF alone is an attractive option for quaternary treatment for urban wastewater reuse.

Contaminant uptake in wastewater irrigated tomatoes

As population growth and climate change add to the problem of water scarcity in many regions, the argument for using treated wastewater for irrigation is becoming increasingly compelling, which makes understanding the risks associated with the uptake of harmful chemicals by crops crucial. In this study, the uptake of 14 chemicals of emerging concern (CECs) and 27 potentially toxic elements (PTEs) was studied in tomatoes grown in soil-less (hydroponically) and soil (lysimeters) media irrigated with potable and treated wastewater using LC-MS/MS and ICP-MS. Bisphenol S, 2,4 bisphenol F, and naproxen were detected in fruits irrigated with spiked potable water and wastewater under both conditions, with BPS having the highest concentration (0.034-0.134 µg kg^-1 f. w.). The levels of all three compounds were statistically more significant in tomatoes grown hydroponically (<LOQ - 0.137 µg kg^-1 f. w.) than in soil (<LOQ - 0.083 µg kg^-1 f. w.). Their elemental composition shows differences between tomatoes grown hydroponically or in soil and tomatoes irrigated with wastewater and potable water. Contaminants at determined levels showed low dietary chronic exposure. When the health-based guidance values for the studied CECs are determined, results from this study will be helpful for risk assessors.

Non-target and suspect-screening analyses of hydroponic soybeans and passive samplers exposed to different watershed irrigation sources

Water scarcity increases the likelihood of irrigating food crops with municipal wastewater that may pose potential dietary risks of regulated and non-regulated organic chemical uptake to edible plant tissues. Only a few studies have used high resolution mass spectrometry (HRMS) to assess the uptake of chemicals of concern into food crops. This study used non-target and suspect-screening analyses to compare total chemical features, tentatively identified chemicals (TICs), and EPA ToxCast chemicals in soybean plants and passive samplers exposed to five different irrigation sources that were collected from an agricultural watershed during mild drought conditions. Secondary-treated municipal wastewater effluent, two surface waters, two ground waters, and deionized municipal tap water were used for two hydroponic experiments: soybean roots and shoots and Composite Integrative Passive Samplers (CIPS) harvested after fourteen days of exposure and soybeans after fifty-six days. CIPS were sealed in separate glass amber jars to evaluate their efficacy to mimic chemical features, TICs, and ToxCast chemical uptake in plant roots, shoots, and beans. Total soybean biomass and water use were greatest for tap water, municipal wastewater, and surface water downstream of the municipal wastewater facility relative to groundwater samples and surface water collected upstream of the wastewater facility. ToxCast chemicals were ubiquitous across watershed irrigation sources in abundance, chemical use category, and number. Wastewater-exposed soybeans had the fewest extractable TICs in plant tissues of all irrigation sources. More ToxCast chemicals were identified in CIPS than extracted from irrigation sources by solid phase extraction. ToxCast chemicals in beans and CIPS were similar in number, chemical use category, and log Kow range. CIPS appear to serve as a useful surrogate for ToxCast chemical uptake in beans, the edible food product.

Soil and Water Management Factors That Affect Plant Uptake of Pharmaceuticals: A Case Study

Water and food security are of global concern. Improving knowledge on crops’ potential uptake of pharmaceutical compounds (PhCs) is necessary to guarantee consumer health and improve the public’s perception of reclaimed water reuse. This study aimed to determine how water management (bottom-up applied for being supplied by Subsurface Drip Irrigation) and the plant rhizosphere effect on the uptake of PhCs. Five PhCs were mixed: atenolol, carbamazepine, dicoflenac, ibuprofen and valsartan. A total of 5 treatments were considered: 3 concentrations of PhCs in agricultural volcanic soil: 0.1, 10 and 100 µg·L−1; 0.1 µg·L−1 in sterilized soil; and a blank with three plant replications at 30, 45, and 60 days after emerging. The maximum quantity of the added PhCs was 100 µg·kg soil−1. A variant of the QuEChERS method was followed to extract PhCs from samples. The limits of quantification were between 10 ng·L−1 and 100 ng·L−1 in extracts. No PhCs over the limits of detection were detected (0.06–0.6 µg·kg−1 of dry plant sample). Hence, the described water reuse methodology poses a negligible consumer risk, which contrasts with hydroponic systems in which this risk has been shown. The results are discussed in terms of the effects of irrigation system, water management and the soil-plant barrier.

Uptake, Occurrence, and Effects of Nonsteroidal Anti-Inflammatory Drugs and Analgesics in Plants and Edible Crops

The plant uptake of pharmaceuticals that include nonsteroidal anti-inflammatory drugs (NSAIDs) and analgesics from contaminated environment has benefits and drawbacks. These pharmaceuticals enter plants mostly through irrigation with contaminated water and application of sewage sludge as soil fertilizer. Aquatic plants withdraw these pharmaceuticals from water through their roots. Numerous studies have observed the translocation of these pharmaceuticals from the roots into the aerial tissues. Furthermore, the occurrence of the metabolites of NSAIDs in plants has been observed. This article provides an in-depth critical review of the plant uptake of NSAIDs and analgesics, their translocation, and toxic effects on plant species. In addition, the occurrence of metabolites of NSAIDs in plants and the application of constructed wetlands using plants for remediation are reviewed. Factors that affect the plant uptake and translocation of these pharmaceuticals are examined. Gaps and future research are provided to guide forthcoming investigations on important aspects that worth explorations.

Specific glutathione-S-transferases ensure an efficient detoxification of diclofenac in Solanum lycopersicum L. plants

Diclofenac (DCF) is a very common pharmaceutical that, due to its high use and low removal rate, is considered a prominent contaminant in surface and groundwater worldwide. In this study, Solanum lycopersicum L. cv. Micro-Tom (tomato) was used to disclose the role of glutathione (GSH)-related enzymes, as GSH conjugation with DCF is a well reported detoxification mechanism in mammals and some plant species. To achieve this, S. lycopersicum plants were exposed to 0.5 and 5 mg L^-1 of DCF for 5 weeks under a semi-hydroponic experiment. The results here obtained point towards an efficient DCF detoxification mechanism that prevents DCF bioaccumulation in fruits, minimizing any concerns for human health. Although a systemic response seems to be present in response to DCF, the current data also shows that its detoxification is mostly a root-specific process. Furthermore, it appears that GSH-mediated DCF detoxification is the main mechanism activated, as glutathione-S-transferase (GST) activity was greatly enhanced in roots of tomato plants treated with 5 mg L^-1 DCF, accompanied by increased glutathione reductase activity, responsible for GSH regeneration. By applying a targeted gene expression analysis, we provide evidence, for the first time, that SlGSTF4 and SlGSTF5 genes, coding for GSTs from phi class, were the main players driving the conjugation of this contaminant. In this sense, and even though tomato plants appear to be somewhat tolerant to DCF exposure, research on GST activity can prove to be instrumental in remediating DCF-contaminated environments and improving plant growth under such conditions.

Micro/nanoplastics effects on organisms: A review focusing on 'dose'

Microplastics have become predominant contaminants, attracting much political and scientific attention. Despite the massively-increasing research on microplastics effects on organisms, the debate of whether environmental concentrations pose hazard and risk continues. This study critically reviews published literatures of microplastics effects on organisms within the context of "dose". It provides substantial evidence of the common occurrence of threshold and hormesis dose responses of numerous aquatic and terrestrial organisms to microplastics. This finding along with accumulated evidence indicating the capacity of organisms for recovery suggests that the linear-no-threshold model is biologically irrelevant and should not serve as a default model for assessing the microplastics risks. The published literature does not provide sufficient evidence supporting the general conclusion that environmental doses of microplastics cause adverse effects on individual organisms. Instead, doses that are smaller than the dose of toxicological threshold and more likely to occur in the environment may even induce positive effects, although the ecological implications of these responses remain unknown. This study also shows that low doses of microplastics can reduce whereas high doses can increase the negative effects of other pollutants. The mechanisms explaining these findings are discussed, providing a novel perspective for evaluating the risks of microplastics in the environment.

Response of Two Crop Plants, Zea mays L. and Solanum lycopersicum L., to Diclofenac and Naproxen

Among numerous contaminants, the ubiquitous occurrence of nonsteroidal anti-inflammatory drugs (NSAIDs) in the environment and their plausible harmful impact on nontarget organisms have made them one of the most important areas of concern in recent years. Crop plants can also potentially be exposed to NSAIDs, since the concentration of these pharmaceuticals is constantly rising in the surface water and soil. Our goal was to evaluate the stress response of two crop plants, maize and tomato, to treatment with selected NSAIDs, naproxen and diclofenac. The focus of the research was on the growth response, photosynthetic efficiency, selected oxidative stress factors (such as the H₂O₂ level and the rate of lipid peroxidation) as well as the total phenolic content, which represents the non-enzymatic protectants against oxidative stress. The results indicate that susceptibility to the NSAIDs that were tested is dependent on the plant species. A higher sensitivity of tomato manifested in growth inhibition, a decrease in the content of the photosynthetic pigments and a reduction in the maximum quantum efficiency of PSII and the activity of PSII, which was estimated using the F_v/F_m and F_v/F₀ ratios. Based on the growth results, it was also possible to reveal that diclofenac had a more toxic effect on tomato. In contrast to tomato, in maize, neither the content of the photosynthetic pigments nor growth appeared to be affected by DFC and NPX. However, both drugs significantly decreased in maize F_v and F_m, which are particularly sensitive to stress. A higher H₂O₂ concentration accompanied, in most cases, increasing lipid peroxidation, indicating that oxidative stress occurred in response to the selected NSAIDs in the plant species that were studied. The higher phenolic content of the plants after NSAIDs treatment may, in turn, indicate the activation of defense mechanisms in response to the oxidative stress that is triggered by these drugs.

Effect of the pharmaceuticals diclofenac and lamotrigine on stress responses and stress gene expression in lettuce (Lactuca sativa) at environmentally relevant concentrations

Vegetable crops irrigated with treated wastewater can take up the environmentally persistent pharmaceuticals diclofenac and lamotrigine. This study aimed at quantifying the uptake and translocation of the two pharmaceuticals in lettuce (Lactuca sativa) as well as on the elucidation of the molecular and physiological changes triggered by them. Therefore, plants were cultivated in a phytochamber in hydroponic systems under controlled conditions and treated independently with diclofenac (20 μg L-1) and lamotrigine (60 μg L-1) for 48 h. A low translocation of lamotrigine but not of diclofenac or its metabolite 4'-hydroxydiclofenac to leaves was observed, which corresponded with the expression of stress related genes only in roots of diclofenac treated plants. We observed an oxidative burst in roots and leaves occurring around the same time point when lamotrigine was detected in leaves. This could be responsible for the significantly changed gene expression pattern in both tissues. Our results showed for the first time that pharmaceuticals like lamotrigine or diclofenac might act as signals or zeitgebers, affecting the circadian expression of stress related genes in lettuce possibly causing a repressed physiological status of the plant.

How microbial community composition, sorption and simultaneous application of six pharmaceuticals affect their dissipation in soils

Pharmaceuticals may enter soils due to the application of treated wastewater or biosolids. Their leakage from soils towards the groundwater, and their uptake by plants is largely controlled by sorption and degradation of those compounds in soils. Standard laboratory batch degradation and sorption experiments were performed using soil samples obtained from the top horizons of seven different soil types and 6 pharmaceuticals (carbamazepine, irbesartan, fexofenadine, clindamycin and sulfamethoxazole), which were applied either as single-solute solutions or as mixtures (not for sorption). The highest dissipation half-lives were observed for citalopram (average DT_50,S for a single compound of 152 ± 53.5 days) followed by carbamazepine (106.0 ± 17.5 days), irbesartan (24.4 ± 3.5 days), fexofenadine (23.5 ± 20.9 days), clindamycin (10.8 ± 4.2 days) and sulfamethoxazole (9.6 ± 2.0 days). The simultaneous application of all compounds increased the half-lives (DT_50,M) of all compounds (particularly carbamazepine, citalopram, fexofenadine and irbesartan), which is likely explained by the negative impact of antibiotics (sulfamethoxazole and clindamycin) on soil microbial community. However, this trend was not consistent in all soils. In several cases, the DT_50,S values were even higher than the DT_50,M values. Principal component analyses showed that while knowledge of basic soil properties determines grouping of soils according sorption behavior, knowledge of the microbial community structure could be used to group soils according to the dissipation behavior of tested compounds in these soils. The derived multiple linear regression models for estimating dissipation half-lives (DT_50,S) for citalopram, clindamycin, fexofenadine, irbesartan and sulfamethoxazole always included at least one microbial factor (either amount of phosphorus in microbial biomass or microbial biomarkers derived from phospholipid fatty acids) that deceased half-lives (i.e., enhanced dissipations). Equations for citalopram, clindamycin, fexofenadine and sulfamethoxazole included the Freundlich sorption coefficient, which likely increased half-lives (i.e., prolonged dissipations).

Comparison of high resolution mrm and sequential window acquisition of all theoretical fragment-ion acquisition modes for the quantitation of 48 wastewater-borne pollutants in lettuce

Screening of a large number of chemicals of emerging concern is highly desirable for the control of crops irrigated with reclaimed water since it is considered an alternative water source of great value. This study describes a high resolution mass spectrometry approach for developing methods for quantification in lettuce leaves of 48 different wastewater-borne pollutants (including analgesics and anti-inflammatories, anti-hypertensives, antifungal agents, lipid regulators, psychiatric drugs and stimulants, β-blockers, antibiotics, antimycotics, and sweeteners) frequently found in water resources. In this respect, a simple and fast QuEChERS-based method for the determination of contaminants in lettuce has been developed. During extraction, the use of formic acid was adopted to further improve the results of some problematic compounds (e.g., fenofibrate, furosemide, metronidazole, oxcarbazepine, sulfanilamide). High resolution multiple reaction monitoring (MRMHR) and SWATH acquisition were compared in term of accuracy, repeatability, sensitivity, linearity and matrix effect. Both methods provided similar recoveries between 80 and 120% in lettuce leaves, although sulfanilamide, ciprofloxacin, and sulfamethazine presenting values of 26.8, 27.8, and 28.4% in MRMHR and 25, 33.9, and 35% in SWATH, respectively. The effectiveness of a two-step cleanup on analyte recovery was also assessed and matrix effects were also taken into consideration during the method validation. The developed method allows the simultaneous quantitative analysis of 48 compounds (drug residues and metabolites) in lettuce leaves irrigated with treated wastewater for human consumption. Application of the present method to lettuce crops growth in controlled conditions showed the presence of 14 out 48 studied compounds with similar concentrations in both acquisition modes ranging from 3.3 and 1.3 ng g - 1 for climbazole (for MRMHR and SWATH, respectively) to 33.2 and 17.7 ng g - 1 for sulfamethazine. Drug residues such as carbamazepine (6.0 and 8.5 ng g - 1), and its metabolite carbamazepine epoxide (18.1 and 16.5 ng g - 1), frequently found in wastewater effluents, were also detected.

Improving yield and quality of vegetable grown in PAEs-contaminated soils by using novel bioorganic fertilizer

Phthalate acid esters (PAEs) are ubiquitous pollutants in agricultural soils. Application of bioorganic fertilizer (BOF) containing beneficial microbes represents a promising approach to improve the yield and quality of crops grown in contaminated soils. In the present study, a novel multifunctional bioorganic fertilizer N-BOF was developed by using compost of sewage sludge and agricultural waste and inoculating with PAEs-degrading B. megaterium YJB3 and phosphate solubilizing B. megaterium YLYP1. Its feasibility of improving the yield and quality of vegetable grown in PAEs (including DBP and DEHP) contaminated soil was evaluated by pot experiments. The N-BOF could effectively promote plant growth, with biomass increasing by 4-66.9% and 19-110% compared to chemical (CF) and no fertilizer (CK), respectively. The concentrations of DBP and DEHP in shoots of chemically fertilised vegetable ranged 1.23-3.12 mg/kg (dry weight, DW) and 1.63-3.89 mg/kg (DW), respectively. Their concentrations were significantly decreased (p < 0.05) when N-BOF was applied (1%, 2%, 5% amendment), especially at higher application rate ranging 0.11-0.3 mg/kg (DW) and 0.16-0.32 mg/kg (DW), respectively. Meanwhile, vegetable quality attributes were also significantly improved when 2% N-BOF was applied, with increase in the contents of vitamin C, vitamin B1, total protein, and starch, and decrease in the contents of nitrite and nitrate. In this case, the human health risk from consumption of the vegetable grown in PAEs-contaminated soil could be significantly reduced. Thus, our study is expected to provide an efficient way of high-value utilization of organic substrates by producing low-cost but high quality N-BOF. Future studies on the effects of N-BOF in terms of fertilizer regimes on yield and quality of the vegetable are needed, and further field studies for assessing the long-term efficacy and reliability of this promising N-BOF are also warranted.

Dissection of the incidence and severity of purple spot physiological disorder in loquat fruit through a physiological and molecular approach

Loquat (Eriobotrya japonica) fruit marketability is affected by the incidence and severity of purple spot (PS), a pre-harvest physiological disorder showing an evident skin discoloration with depressed surface. Despite its impact in limiting the cultivation and economic potential of loquat, the etiology of this disorder is still poorly understood. To this end, our study aimed to investigate and disclose possible mechanisms underlying PS development. The intensity and severity of PS in three loquat cultivars ('Morphitiki', 'Karantoki' and 'Obusa') was phenotypically monitored during successive on-tree fruit developmental stages. 'Obusa' fruits harvested at commercial maturity stage showed the highest incidence of purple spot (58.6%), while 'Morphitiki' fruits did not show any symptoms. 'Karantoki' fruits demonstrated an intermediate response, with 31.3% of the fruit being affected. Thereafter, fruits with 30-50% PS severity were selected and used for further analysis; peel tissue was removed from both symptomatic and asymptomatic tissue of the same fruit for all examined cultivars. 'Karantoki' fruit with PS were characterized by the highest accumulation of total soluble sugars, sucrose, glucose and fructose contents, while the concentration of these primary metabolites was the lowest in asymptomatic fruit of 'Obusa', exception made for the sucrose. The incidence of PS was also transcriptionally investigated by assessing the mRNA profile of important genes involved in polyphenolic (PAL1, PAL2 and PPO1) and carbohydrate (CWI2, CWI3, SPS1, SPS2, NI2, NI3, SuSy, HXK, FRK and VI) pathway. The enhanced expression levels of CWI3 and VI genes in symptomatic fruit of the highly susceptible cultivar 'Obusa' highlight a cultivar-specific type of response. Notably, SuSy registered significantly suppressed levels in symptomatic tissue of both 'Obusa' and 'Karantoki'. To what extent PPO is associated with PS incidence and whether the etiology of the disorder can be assigned to an oxidative process triggered and coordinated by its action need to be further elucidated. The aforementioned genes are suggested to be further examined as potential markers towards a more sophisticated and informed characterization of purple spot detection in loquat fruit.

Individual and mixture toxicity evaluation of three pharmaceuticals to the germination and growth of Lactuca sativa seeds

This work aims to assess, individually and in mixtures, possible phytotoxic effects of three pharmaceuticals (paracetamol, ibuprofen and amoxicillin) on germination and early growth of Lactuca sativa seeds. Pharmaceuticals are an important group of emerging contaminants, whose presence has been described in several environmental compartments, including soils. However, knowledge on their possible impact in terrestrial organisms is still sparse and even more when mixtures are considered. Germination tests are important to evaluate the quality of soil and the toxic effects that contaminants can pose to plants. The acute effects of individual pharmaceuticals as well as binary and ternary mixtures were assessed using different endpoints, namely: percentage of seed germination, root elongation, shoot and leaf length, after an exposure time of five days. Overall, in the exposure of L. sativa seeds to individual pharmaceuticals there are indications of acute toxicity in the early plant growth. However, this inhibitory effect tends to be cancelled in the acute exposure to mixtures. This study shows the importance of evaluating the toxicity of mixtures of pharmaceuticals, since they might have distinct toxic effects when compared to the single compounds, and also because, probably, it is the closest scenario to the reality that can be found in the environment.

The dynamics of the pharmaceutical and personal care product interactive capacity under the effect of artificial enrichment of soil with heavy metals and of wastewater reuse

A greenhouse experiment was conducted, using a randomized block design, including twelve heavy metal (Mn, Zn, Cu, Cd, Co, Cr, Ni, Pb) mixture treatments, with each metal participating in the treatment with 0, 2, 4, 6, 8, 10, and 12 mg/kg, respectively. Common beet (Beta vulgaris L.) was chosen as test plant. The plants were irrigated with treated municipal wastewater taken from the Wastewater Treatment Plant of the town of Amaliada, N.W., Peloponnese, Greece. The experiment aimed at studying the interactions between heavy metals and macro-microelements, and pharmaceuticals and personal care products (PPCPs). The basic scope was to shed some light on the potential environmental implications, of these interactions on the soil PPCPs for a more effective monitoring of these emerging contaminants in the plants and soil continuum. It was found that the PPCPs have a very high potential interactive capacity, having interacted with all the studied metals, and metalloids, as well as with plant macro elements (P, and K). The uptake of PPCPs by plants was statistically significantly related with their respective content in the soil. The general inference is that the interactive relations between heavy metals, macro-, microelements, and emerging contaminants, being mainly antagonistic, which contribute to the decrease the uptake of soil PPCPs.

Bioaccumulation of antibiotics in crops under long-term manure application: Occurrence, biomass response and human exposure

Long-term manure application gives rise to the uptake of antibiotics by plants and antibiotics subsequent entry into the food chain, representing an important alternative pathway for human exposure to antibiotics. The antibiotics can cause negative effects on crop growth and productivity. The bioaccumulation and translocation of 14 target antibiotics in peanuts (Arachis hypogaea L.) and their effects on peanut relative biomass in fields with long-term (≥15 years) manure application were studied. The results showed that all the target antibiotics were found in manures and rhizosphere soils, and most of them were found in all peanut tissues (roots, shells, kernels, stem, and leaves). The antibiotic concentrations in peanut tissues were varied with the characteristics of antibiotics in soils. Tetracyclines were the dominating antibiotic compounds in all peanut tissues, accounting for 61%-80% of total antibiotics due to their relatively high concentration in rhizosphere soil. Most tetracyclines and quinolones preferentially accumulated in the roots and translocated to other peanut tissues than sulfonamides and macrolides. Furthermore, the influence of antibiotics in soil and crops on relative biomass of crop tissues varied with tissues and antibiotic types. Antibiotics significantly inhibited the tissue relative biomass in most cases, although stimulation of some antibiotics to crop biomass was also observed. We found that 18.3% of the variance of the peanut relative biomass was explained by antibiotics in soils and tissues. The estimated threshold of daily intake values suggests that the consumption of peanut kernels grown in field conditions with long-term manure application presents a moderate risk to human health.