Uptake of Pharmaceutical Pollutants and Their Metabolites from Soil Fertilized with Manure to Parsley Tissues

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.

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.

Sequential Anaerobic-Aerobic Treatment Enhances Sulfamethoxazole Removal: From Batch Cultures to Observations in a Large-Scale Wastewater Treatment Plant

Sulfamethoxazole (SMX) passes through conventional wastewater treatment plants (WWTPs) mainly unaltered. Under anoxic conditions sulfate-reducing bacteria can transform SMX but the fate of the transformation products (TPs) and their prevalence in WWTPs remain unknown. Here, we report the anaerobic formation and aerobic degradation of SMX TPs. SMX biotransformation was observed in nitrate- and sulfate-reducing enrichment cultures. We identified 10 SMX TPs predominantly showing alterations in the heterocyclic and N4-arylamine moieties. Abiotic oxic incubation of sulfate-reducing culture filtrates led to further degradation of the major anaerobic SMX TPs. Upon reinoculation under oxic conditions, all anaerobically formed TPs, including the secondary TPs, were degraded. In samples collected at different stages of a full-scale municipal WWTP, anaerobically formed SMX TPs were detected at high concentrations in the primary clarifier and digested sludge units, where anoxic conditions were prevalent. Contrarily, their concentrations were lower in oxic zones like the biological treatment and final effluent. Our results suggest that anaerobically formed TPs were eliminated in the aerobic treatment stages, consistent with our observations in batch biotransformation experiments. More generally, our findings highlight the significance of varying redox states determining the fate of SMX and its TPs in engineered environments.

Efficiency of phytoremediation and identification of biotransformation pathways of fluoroquinolones in the aquatic environment

Phytoremediation is a low-cost and sustainable green technology that uses plants to remove organic and inorganic pollutants from aquatic environments. The aim of this study was to investigate the phytoextraction, phytoaccumulation, and phytotransformation of three fluoroquinolones (FQs) (ciprofloxacin [CIP], enrofloxacin [ENF], and levofloxacin [LVF]) by Japanese radish (Raphanus sativus var. longipinnatus) and duckweed (Lemma minor). Determination of FQs and identification of their transformation products (TPs) were performed using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). Inter-tissue translocation of FQs in Japanese radish tissues depended on their initial concentration in the medium. CIP (IT = 14.4) and ENF (IT = 17.0) accumulated mainly in radish roots, while LVF in leaves (IT = 230.8) at an initial concentration of 10 µg g-1. CIP (2,104 ng g-1) was detected in the highest concentration, followed by ENF (426.3 ng g-1) and LVF (273.3 ng g-1) in the tissues of both plants. FQs' bioaccumulation factors were significantly higher for duckweed (1.490-18.240) than Japanese radish (0.027-0.103). The removal of FQs from water using duckweed was mainly due to their photolysis and hydrolysis than plant sorption. In the screening, analysis detected 29 FQ TPs. The biotransformation pathways of FQs are described in detail, and the factors that influence their formation are indicated.

Mechanism and synergistic effect of sulfadiazine (SDZ) and cadmium toxicity in spinach (Spinacia oleracea L.) and its alleviation through zinc fortification

Cadmium (Cd) and antibiotic's tendency to accumulate in edible plant parts and fertile land is a worldwide issue. The combined effect of antibiotics and heavy metals on crops was analyzed, but not mitigation of their toxicity. This study investigated the potential of zinc oxide nanoparticles (ZnO NPs) to alleviate the SDZ and Cd toxicity (alone/combined) to promote spinach growth. Results revealed that the ZnO 200 mg L-1 spray decreased the malondialdehyde (MDA) 14%, hydrogen peroxide (H2O2) 13%, and electrolyte leakage (EL) 7%, and increased the superoxide dismutase (SOD) 8%, peroxidase (POD) 25%, catalase (CAT) 39% and ascorbate peroxidase (APX) 12% in spinach leaves under combined SDZ+Cd (25 mg Kg-1 +50 mg Kg-1) stress compared to ZnO 100 mg L-1 spray. Likewise, ZnO NPs 200 mg L-1 spray enhanced the zinc (Zn) 97%, iron (Fe) 86%, magnesium (Mg) 35%, manganese (Mn) 8%, and potassium (K) 23% in shoots under combined SDZ+Cd (25 mg Kg-1 +50 mg Kg-1) stress compared to ZnO 100 mg L-1 spray. Further, ZnO 200 mg L-1 spray reduced Cd uptake in roots by 9% and shoots 15% under combined SDZ+Cd (25 mg Kg-1 +50 mg Kg-1) stress compared to ZnO 100 mg L-1. Overall, ZnO NPs alleviated the SDZ and Cd toxicity and enhanced spinach growth in all treatments.

Anthelmintics in the environment: Their occurrence, fate, and toxicity to non-target organisms

Anthelmintics are drugs used for the treatment and prevention of diseases caused by parasitic worms (helminths). While the importance of anthelmintics in human as well as in veterinary medicine is evident, they represent emerging contaminants of the environment. Human anthelmintics are mainly used in tropical and sub-tropical regions, while veterinary anthelmintics have become frequently-occurring environmental pollutants worldwide due to intensive agri- and aquaculture production. In the environment, anthelmintics are distributed in water and soil in relation to their structure and physicochemical properties. Consequently, they enter various organisms directly (e.g. plants, soil invertebrates, water animals) or indirectly through food-chain. Several anthelmintics elicit toxic effects in non-target species. Although new information has been made available, anthelmintics in ecosystems should be more thoroughly investigated to obtain complex knowledge on their impact in various environments. This review summarizes available information about the occurrence, behavior, and toxic effect of anthelmintics in environment. Several reasons why anthelmintics are dangerous contaminants are highlighted along with options to reduce contamination. Negative effects are also outlined.

Study of the Phytoextraction and Phytodegradation of Sulfamethoxazole and Trimethoprim from Water by Limnobium laevigatum

Phytoremediation is an environmentally friendly and economical method for removing organic contaminants from water. The purpose of the present study was to use Limnobium laevigatum for the phytoremediation of water from sulfamethoxazole (SMX) and trimethoprim (TRI) residues. The experiment was conducted for 14 days, in which the loss of the pharmaceuticals in water and their concentration in plant tissues was monitored. Determination of SMX and TRI was conducted using liquid chromatography coupled with tandem mass spectrometry. The results revealed that various factors affected the removal of the contaminants from water, and their bioaccumulation coefficients were obtained. Additionally, the transformation products of SMX and TRI were identified. The observed decrease in SMX and TRI content after 14 days was 96.0% and 75.4% in water, respectively. SMX removal mainly involved photolysis and hydrolysis processes, whereas TRI was mostly absorbed by the plant. Bioaccumulation coefficients of the freeze-dried plant were in the range of 0.043-0.147 for SMX and 2.369-2.588 for TRI. Nine and six transformation products related to SMX and TRI, respectively, were identified in water and plant tissues. The detected transformation products stemmed from metabolic transformations and photolysis of the parent compounds.