Uptake and accumulation of erythromycin in leafy vegetables and induced phytotoxicity and dietary risks

Uptake, subcellular accumulation and metabolism of 14C-bisphenol S in flowering cabbage

Due to the growing environmental and health concerns surrounding bisphenol S (BPS) as a common bisphenol A (BPA) substitute, this study investigated the metabolic pathways and tissue-specific accumulation of BPS in flowering cabbage under hydroponic conditions, revealing key insights into plant detoxification processes and potential human health risks. Over a 32-day exposure of 5 mg L-1 14C-BPS, 60.2 ± 3.0 % of 14C in the nutrient solution was taken up, with the 14C-radioactivity accounting for 40.2 ± 2.6 %, 5.3 ± 0.3 %, and 14.5 ± 0.6 % in roots, stems, and leaves, respectively. Older leaves retained higher levels of BPS and/or its metabolites. Using HPLC-LSC, LC-MS/MS, and subcellular fractionation, we identified four metabolites, characterized by glycosylation, malonylation, sulfation, and amino acid conjugation pathways. BPS and its metabolites were primarily located in the cell wall, plastid, and soluble component. The segregation of BPS and metabolites into the cell wall and plastid resulted in the formation of large amounts of non-extractable residues in roots. Results highlight that BPS metabolites, particularly glycosylated forms like M526, may accumulate in edible plant parts. These findings advance understanding of BPS metabolism in plants, underlining the potential food safety risks posed by its uptake and metabolism in agricultural systems.

Uptake, Subcellular Distribution, and Metabolism of Decabromodiphenyl Ethane in Vegetables under Different Exposure Scenarios

Decabromodiphenyl ethane (DBDPE), a key alternative to deca-BDE (BDE-209), has been ubiquitous in the receiving ecosystem. However, little is known about its uptake process and fate in plants. Here, the plant absorption, distribution, and metabolism of 14C-DBDPE under two distinct exposure pathways (i.e., soil-root and airborne dust-leaf) were investigated with three vegetables (cherry radish, water spinach, and eggplant). DBDPE was absorbed and primarily accumulated in directly exposed roots and leaves, with translocation factors to other tissues of 0.04-0.77 and 0.73-12.80 × 10-3, respectively. DBDPE in exposed leaves was more difficult to transport as most DBDPE did not enter the interior of the leaves but was stored in waxes (>90%). Furthermore, DBDPE within leaves was found to enter mostly through waxy layer penetration (>97%). The majority of 14C-DBDPE was localized in cell walls (52.6 and 75.6%, respectively) and organelles (22.7 and 45.5%, respectively) of exposed tissues, substantially restricting its in-plant translocation. Debrominated products were detected in exposed roots, but barely found in exposed leaves, as most DBDPE was blocked by the waxy layer. Moreover, DBDPE was stable in soils and dust without degradation. Our findings contribute to a deeper understanding of the environmental fate of DBDPE in soil-plant and airborne dust-plant systems.

Occurrence, dissipation kinetics and environmental risk assessment of antibiotics and their metabolites in agricultural soils

Antibiotics are among the emerging contaminants of greatest concern to the scientific community. However, the occurrence and behaviour of their metabolites in soils have been scarcely studied. To address this research gap, this study investigates the occurrence, sorption, dissipation kinetics, and environmental risk of highly important antibiotics (sulfamethazine, sulfadiazine, sulfamethoxazole, trimethoprim) and their main metabolites in Mediterranean agricultural soils. Batch experiments were conducted under natural conditions for 120 days. Five different dissipation kinetics models were applied to elucidate antibiotics degradation. The sorption isotherms were evaluated by three different models. Most of the antibiotics and metabolites tested showed a good fit with the Linear Isotherm model (R2 >0.96) and biphasic dissipation kinetic models (R2 >0.90). The dissipation and the endpoints values (DT50 and DT90) depended on the soil type properties. A Lixisol soil demonstrated reduced degradation of the investigated compounds. Trimethoprim showed the highest persistence, followed by sulfamethazine, sulfamethoxazole, and sulfadiazine. Parent compounds exhibited lower degradation rates than their metabolites. Remaining antibiotic concentrations were found to be below the predicted no-effect concentration in soil, suggesting that they may not pose a risk to terrestrial biota. This study provides valuable insights into the behaviour of these antibiotics and their metabolites in soil.

Antibiotic residue contamination in the aquatic environment, sources and associated potential health risks

Antibiotic residues are widely recognized as major pollutants in the aquatic environment on a global scale. As a significant class of pharmaceutically active compounds (PhACs), antibiotics are extensively consumed worldwide. The primary sources of these residues include hospitals, municipal sewage, household disposal, and manures from animal husbandry. These residues are frequently detected in surface and drinking waters, sewage effluents, soils, sediments, and various plant species in countries such as China, Japan, South Korea, Europe, the USA, Canada, and India. Antibiotics are used medicinally in both humans and animals, with a substantial portion excreted into the environment as metabolites in feces and urine. With the advancement of sensitive and quantitative analytical techniques, antibiotics are consistently reported in environmental matrices at concentrations ranging from nanograms per liter (ng/L) to milligrams per liter (mg/L). Agricultural soils, in particular, serve as a significant reservoir for antibiotic residues due to their strong particle adsorption capacities. Plants grown in soils irrigated with PhAC-contaminated water can uptake and accumulate these pharmaceuticals in various tissues, such as roots, leaves, and fruits, raising serious concerns regarding their consumption by humans and animals. There is an increasing need for research to understand the potential human health risks associated with the accumulation of antibiotics in the food chain. The present reviews aims to shed light on the rising environmental pharmaceutical contamination concerns, their sources in the environment, and the potential health risks as well as remediation effort. To discuss the main knowledge gaps and the future research that should be prioritized to achieve the risk assessment. We examined and summarized the available data and information on the antibiotic resistance associated with antibiotic residues in the environment. As studies have indicated that vegetables can absorb, transport, and accumulate antibiotics in edible parts when irrigated with wastewater that is either inadequately treated or untreated. These residues and their metabolites can enter the food chain, with their persistence, bioaccumulation, and toxicity contributing to drug resistance and adverse health effects in living organisms.

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.

Urban agglomerations as an environmental dimension of antibiotics transmission through the "One Health" lens

The spatiotemporal distributions of antibiotics in different media have been widely reported; however, their occurrence in the environmental dimension of the Chinese urban agglomerations has received less attention, especially in bioaccumulation and health risks of antibiotics through the "One Health" lens. The review presents the current knowledge on the environmental occurrence, bioaccumulation, as well as health exposure risks in urban agglomerations through the "One Health" lens, and identifies current information gaps. The reviewed studies suggested antibiotic concentrations in water and soil were more sensitive to social indicators of urban agglomerations than those in sediment. The ecological risk and resistance risk of antibiotics in water were much higher than those of sediments, and the high-risk phenomenon occurred at a higher frequency in urban agglomerations. Erythromycin-H2O (ETM-H2O), amoxicillin (AMOX) and norfloxacin (NFC) were priority-controlled antibiotics in urban waters. Tetracyclines (TCs) posed medium to high risks to soil organisms in the soil of urban agglomerations. Health risk evaluation based on dietary intake showed that children had the highest dietary intake of antibiotics in urban agglomerations. The health risk of antibiotics was higher in children than in other age groups. Our results also demonstrated that dietary structure might impact health risks associated with target antibiotics in urban agglomerations to some extent.

Antibiotic resistance gene distribution in Shine Muscat grapes and health risk assessment of streptomycin residues in mice

Antibiotic residues and antibiotic resistance genes (ARGs) in fruits and vegetables pose public health risks via the food chain, attracting increased attention. Antibiotics such as streptomycin, used directly on seedless grapes or introduced into vineyard soil through organic fertilizers. However, extensive data supporting the risk assessment of antibiotic residues and resistance in these produce remains lacking. Utilizing metagenomic sequencing, we characterized Shine Muscat grape antibiotic resistome and mobile genetic elements (MGEs). Abundant MGEs and ARGs were found in grapes, with 174 ARGs on the grape surface and 32 in the fruit. Furthermore, our data indicated that soil is not the primary source of these MGEs and ARGs. Escherichia was identified as an essential carrier and potential transmitter of ARGs. In our previous study, streptomycin residue was identified in grapes. Further short-term exposure experiments in mice revealed no severe physiological or histological damage at several environment-related concentrations. However, with increased exposure, some ARGs levels in mouse gut microbes increased, indicating a potential threat to animal health. Overall, this study provides comprehensive insights into the resistance genome and potential hosts in grapes, supporting the risk assessment of antibiotic resistance in fruits and vegetables.

The erythromycin sorption removal at environmentally relevant concentration based on molecular imprinted polymer: Performance and mechanism

The antibiotic pollution emerged in different environments has raised a great concern. Adsorption is an effective method to solve the problem. However, conventional adsorbents are not always efficient for antibiotic removal with interferences. Therefore, in this study, molecularly imprinted polymer (EMIP) with selective adsorption ability was prepared to remove a typical antibiotic-erythromycin (ERY) at environmentally relevant concentration. The specific surface area of EMIP was 265.62 m2/g with large pore volume, small pore size and hydrophobic surface. The adsorption capacity of EMIP was increased from 211.08 to 4015.51 μg/g when the concentration of ERY was increased from 5.00 to 100.00 μg/L. The isothermal adsorption process was fitted well with the Langmuir model. The adsorption kinetic could be well described by the pseudo-second-order model. With co-existing of interferences, the imprinting factor for ERY was 2.57, which demonstrated EMIP had good adsorption selectivity. After five consecutive adsorption-desorption experiments, the adsorption capacity of EMIP was still over 80%. The results of molecular dynamic simulation showed the adsorption energy between ERY and EMIP was high, which was favorable for ERY adsorption removal. Hopefully, the results of this study could provide new insights for trace antibiotic removal by molecular imprinting polymers in different aqueous environments.