Avermectin (AVM) has been widely used in agriculture and animal husbandry based on its broad spectrum of effective anthelmintic activity and specificity targets. However, AVM induction of cytotoxicity in human liver is largely unknown. In this study, we investigate the cytotoxic effects of AVM on HepG2 cells in vitro. The results revealed that AVM inhibited the viability of HepG2 cells and enhanced apoptosis. Established assays of cytotoxicity were performed to characterize the mechanism of AVM toxicity on HepG2 cells. Typical apoptosis morphological changes were shown in AVM-treatment cells including chromatin condensation and DNA fragmentation. We demonstrated that AVM-induced apoptosis of HepG2 cells were mediated by generated ROS. Moreover, a decrease in mitochondrial membrane potential (MMP) and up-regulating the Bax/Bcl-2 ratio, resulted in a release of cytochrome-c as well as activation of caspase-9/-3. In conclusion, our experimental results show that AVM has a potential threat to human health which may be induce apoptosis of human hepatocyte cells via caspase-dependent mitochondrial pathways.

Anthelmintics, drugs against parasitic worms, are frequently used in livestock and might act as danger environmental microcontaminants. The present study was designed to monitor the possible circulation of common anthelmintic drug albendazole (ABZ) and its metabolites in the real agriculture conditions. The sheep were treated with the recommended dose of ABZ. Collected faeces were used for the fertilization of a field with fodder plants (alfalfa and clover) which served as feed for sheep from a different farm. The selective ultrasensitive mass spectrometry revealed surprisingly high concentrations of active ABZ metabolite (ABZ-sulphoxide) in all samples (dung, plants, ovine plasma, rumen content and faeces). Our results prove for the first time an undesirable permeation of ABZ metabolites from sheep excrement into plants (used as fodder) and subsequently to other sheep in real agricultural conditions. This circulation causes the permanent exposition of the ecosystems and food-chain to the drug and can promote the development of drug resistance in helminths.

This study was carried out to provide baseline information on the concentrations of pharmaceuticals in Kuwait's coastal waters. Samples were collected over four sampling campaigns from various outfalls that occasionally discharged water into the marine environment and analyzed for a range of pharmaceuticals including analgesic/anti-inflammatories, antibiotics, anticoagulant, antidiabetic, antihelmintics, antihypertensives, antiplatelet agent, asthma medication, β-blocking agent, calcium channel blocker, diuretic, histamine H1 and H2 receptor antagonist, lipid regulators/cholesterol-lowering, prostatic hyperplasia, psychiatric drug, sedation and muscle relaxant, synthetic glucocorticoid, tranquilizer and x-ray contrast media. The levels varied between the detection limits of the method and a maximum of 28,183 ng/L for analgesics/anti-inflammatories. The highest pharmaceutical concentrations were in samples collected during the September campaign, possibly linked to the increased prescription of these medications to treat infectious diseases and flu prevalent in Kuwait during the winter months. The spatial variation is concentration is evident with KISR site being most polluted as hospital wastewater is discharged at the site. This study provides the first dataset on the concentrations of pharmaceuticals in the seawater in Kuwait and possibly the wider Arabian Gulf. Kuwait's coastal water pharmaceutical concentrations derived from this study exceed those reported from the Spanish coast, the Hong Kong harbour, the Bohai and the Yellow seas. More studies are needed to evaluate the environmental impact that these residues may have on non-target organisms.

In this work, a multi-class analytical method for determination of 22 frequently used pharmaceuticals was developed and validated. Analytes were from different classes for example macrolides, fluoroquinolones, tetracyclines, sulfonamides, anthelmintics, anesthetics, and others. Method was intended for analysis of aqueous samples so the sample preparation was done using solid-phase extraction (SPE). Different sorbents (C8, C18, polymeric, and ion exchange sorbents) combining different eluents (methanol, ethanol, acetonitrile, acetone, ethyl acetate) were investigated during development of sample preparation step. Samples were analyzed using HPLC-MS/MS, and therefore, chromatographic and mass spectrometer conditions were investigated. Optimal extraction efficiencies for most of the investigated analytes were obtained with Oasis HLB polymeric sorbents with acetonitrile as eluent. A study of matrix effect was carried out for wastewater treatment plant (WWTP) influent and effluent. The method was validated for linearity, detection limits and quantification limits, repeatability, and reproducibility. Method detection limits were in the range of 2.0–204.0 ng L⁻¹ for WWTP influent except for sulfaguanidine and dexamethasone. Also, method detection limits for WWTP effluent were from 1.0 to 115.4 ng L⁻¹. Method was successfully applied for analysis of real wastewater samples from municipal wastewater treatment plant. In the influent, pharmaceuticals from all investigated groups were present and the concentrations were from 50.0 to 4914.3 ng L⁻¹ for influent and 26.9 to 1699.2 ng L⁻¹ for effluent. It was also reported that some pharmaceuticals showed higher concentrations in the wastewater effluent than in the influent.