Residues of organochlorine pesticides and polycyclic aromatic hydrocarbons in farm-raised livestock feeds and manures in Jiangsu, China

Insights into the Fate of the Novel Pesticide Vanisulfane from Animal Manure in Plant-Soil Systems: Assisted by Carbon-14 Labeling

Pesticide use can result in plant residues, which can be ingested by livestock consuming plant-derived feed and appear in manure. When this manure is applied as a fertilizer, pesticides can contaminate plant-soil systems. Few studies have focused on pesticide infiltration from applying pesticide-contaminated manure to land. In this study, the fate of pesticide vanisulfane from chicken manure was studied in radish-soil and cabbage-soil systems assisted by carbon-14 labeling. Vanisulfane and its metabolites mostly appeared as bound residues (BRs) after introduction, and BR release was found at 35 d. Notably, manure contaminated with vanisulfane and its metabolites exhibited higher plant accumulation and phytotoxicity than manure contaminated with only the parent. Four metabolites were identified, and germination toxicity assays illustrated that a metabolite with an aldehyde structure induced phytotoxicity. This study provides valuable information on pesticide contamination from manure and emphasizes the importance of considering pesticide metabolites when assessing environmental risks.

Assessing the fate of antibiotics and agrochemicals during anaerobic digestion of animal manure

Antibiotics and pesticides are used extensively by the livestock industry. Agricultural chemicals can pose potential human and environmental health risks due to their toxicity and through their contributions to antimicrobial resistance, and strategies to reduce their emission into the environment are urgently needed. Anaerobic digestion (AD) is a sustainable technology for manure management that produces biogas while also providing an opportunity to degrade agricultural chemicals that are present in manure. While the effects of selected chemicals on biogas production have been investigated previously, little is known about chemical transformations during AD. Using lab-scale AD batch reactors containing dairy manure, degradation kinetics and transformation products (TPs) were investigated for twenty compounds that are likely to be present in manure management systems and that we hypothesized would transform during AD. Digestate samples were extracted using a modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method and analyzed using liquid chromatography - high-resolution mass spectrometry. Eleven of the tested chemicals degraded, leading to the formation of 47 TPs. Three compounds degraded abiotically only, two degraded biotically only, and six degraded both abiotically and biotically. These results suggest that in addition to renewable energy generation, AD contributes to the degradation of chemical contaminants present in agricultural waste streams. However, the potential toxic effects of TPs require further investigation.

Accumulation and biotransformation of the novel vanillin-derived pesticide, vanisulfane, in laying hens after dietary exposure

Vanisulfane is a novel plant antiviral agent with promising prospects to prevent and control viral crop diseases. However, human health risk assessment after vanisulfane exposure from animal-derived food products remains limited. To gain insight into the accumulation and biotransformation of vanisulfane in livestock, laying hens were dietary exposed to ¹⁴C-vanisulfane. Although more than 80 % of the applied dose was observed in the excreta, vanisulfane and its metabolites accumulated in tissues, especially the liver and kidney, and was found to be transferred to eggs. A total of eight metabolites associated with both phase I and phase II metabolism were identified via ¹⁴C tracing and LC-QTOF-MS. Phase I metabolism included oxidation, hydroxylation, dechlorination and demethylation, and phase II metabolism was associated with sulfonic acid and glucuronide conjugation. The high percentages of metabolites in laying hens' tissues and organs, illustrated the active biotransformation of vanisulfane in vivo, which suggests that the marker residues of vanisulfane should consider its major metabolites. A digestive model was also used to determine the digestive fate of vanisulfane. This study improves our understanding of vanisulfane accumulation and biotransformation in laying hens, which will be helpful for risk assessments of foods derived from animals exposed to pesticides.

Presence of pesticides and biocides at Dutch cattle farms participating in bird protection programs and potential impacts on entomofauna

In spite of meadow bird protection programs, a severe decline of meadow birds is taking place in the Netherlands. It is hypothesized that pesticides and other agrochemicals may contribute to this decline through a negative impact on the entomofauna; a very important food source of meadow birds and especially of their chicks. The present study analysed the presence of 664 pesticides (including biocides and some metabolites) in soil, concentrated feed, manure and some fodder samples from 23 cattle farms in the province of Gelderland (the Netherlands). Furthermore, the presence of 21 anti-parasitic medicines in manure from storage facilities was analysed. For farms practicing field grazing, the number of dung beetles in field samples of fresh manure was determined and a potential relationship with the presence of pesticide residues was explored. Of the 23 farms included in present study, 22 participated in meadow bird protection schemes. A total of 129 different pesticides (including biocides and metabolites) was detected, of which 115 at the 15 conventional farms and 69 at the 8 certified organic farms. The average total amount of pesticide residues detected tended to be lower at organic cattle farms than at conventional farms; for organic concentrated feed this difference was significant at a factor of 3.7. A significant negative correlation was found between the estimated daily intake of insecticides by cattle through the consumption of concentrated feed and hay, and the numbers of dung beetles detected in fresh manure samples in the field. We discuss the most important insecticides detected in concentrated feed and hay, and conclude that their quantities in manure and feed, if compared with LR50 values, give a reason for concern. More research is needed to establish the role of agrochemicals in the decline of meadow birds.

Distribution and Potential Sources of OCPs and PAHs in Waters from the Danshui River Basin in Yichang, China

To investigate the concentrations, spatial distribution, potential sources and mass fluxes of organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) in waters from the Danshui River Basin, a total of 20 water samples were collected and analyzed from a karstic river in Western Hubei of Central China. The average concentrations of total OCPs and PAHs in the river water were 4719 pg·L^-1 and 26.2 ng·L^-1, respectively. The characteristic ratios of different isomers and the composition analysis of individual OCPs and PAHs revealed that HCHs originated from a mixed input of technical HCHs and Lindane, DDTs were mainly from technical DDTs, and PAHs mainly originated from biomass and coal combustion. The mass flux analysis showed that PAHs had a higher emission and heavier burden than OCPs in the Danshui River Basin. OCPs and PAHs emitted from agricultural or other human activities could enter the groundwater and then be transported to the surface/river water in the karst area. The adsorption of OCPs and PAHs by particles and the sedimentation of particles could be the primary processes to intercept these pollutants in the water of the karstic river system.

Investigating the degradation behavior of Cypermethrin (CYP) and Chlorpyrifos (CPP) in peach orchard soils using organic/inorganic amendments

Reducing toxic effects of pesticide residues in agricultural soils through organic amendments is an eco-friendly technique. Cypermethrin (CYP) and Chlorpyrifos (CPP) are widely used pesticides in peach growing orchards in Swat valley of Pakistan. The aim of the current study was to investigate the degradation behavior of CYP and CPP in soil by the application of different combination of organic/inorganic amendments. A total of 36 soil samples were used in the current incubation study which was collected from 4 peach orchards in district Swat, Khyber Pakhtunkhwa (KPK), Pakistan. Different amendments including urea, farm yard manure (FYM) and saprofil were applied alone and in various combinations. The initial concentrations of CYP and CPP in the tested soil was range from 0.94 to 4.8 mg kg⁻¹ and 0.024 to 4.12 to mg kg⁻¹. Soil samples were taken at 5, 15, 30 and 45 days after exposure to different treatments. The extraction of pesticides from soils was done through quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method. Soils amended with urea, FYM and saprofil individually and in combinations significantly reduced the concentrations of CYP and CPP. However, the concentration of CYP (24.6) and CPP (27.0) in soil showed higher reduction through the application of FYM. While the concentrations of CYP and CPP were declined with the 5, 15, 30 and 45 days intervals, however, reduction at day 30 and 45 was faster for CYP (16.7 to 8.46) than CPP (20.2 to 12.3). At day 5 and 15, the CYP (42.5 to 30.7) was slightly lower than CPP (42.9 to 32.7).The highest half-life value (t ½) of CYP was in control treatment (32 days) and the shortest was soil amended with FYM (18.6 days). While the longest half-life value (t ½) of CPP was maximum in control treatment (42 days) and the minimum was in FYM (22 days). Based on our findings, it was concluded that soil application of FYM is recommended for the degradation of CYP and CPP.

Review on the fate of antimicrobials, antimicrobial resistance genes, and other micropollutants in manure during enhanced anaerobic digestion and composting

While manure has been used as nutrient-rich fertilizer for centuries, anaerobic digestion (AD) of manure has only been recognized recently as a promising renewable energy source for producing methane-rich biogas. Various forms of AD have been evaluated for the removal of manure contaminants, such as antimicrobials, antimicrobial resistance genes (ARGs), hormones, and pesticides that pose risks to human health and the environment. Increasing demand for cleaner energy prompts examination of the fate of manure contaminants in conventional and advanced AD techniques. This review reveals that removal of contaminants differs based on type (e.g. antimicrobials vs hormones) or class (e.g. tetracyclines vs sulfonamides) of chemicals being treated. Increasingly, pre-treatment techniques are incorporated into AD systems to enhance biogas production and degrade manure contaminants. For instance, activated carbon with microwave pretreatment removed 87-95% of ARGs. Advanced anaerobic digestion and solid-state anaerobic digestion reduced various ARGs associated with sulfonamides, macrolides, and tetracyclines. Further, total hormone reduction improved using high-temperature pretreatment prior to mesophilic AD. Finally, several studies revealed partial removal of antimicrobials and ARGs during managed composting. Although AD can independently decrease manure contaminants prior to use as fertilizer, augmenting AD with composting and other physical treatment processes can further enhance their removal.

Widespread Pig Farming Practice Linked to Shifts in Skin Microbiomes and Disease in Pond-Breeding Amphibians

Farming practices may reshape the structure of watersheds, water quality, and the health of aquatic organisms. Nutrient enrichment from agricultural pollution increases disease pressure in many host-pathogen systems, but the mechanisms underlying this pattern are not always resolved. For example, nutrient enrichment should strongly influence pools of aquatic environmental bacteria, which has the potential to alter microbiome composition of aquatic animals and their vulnerability to disease. However, shifts in the host microbiome have received little attention as a link between nutrient enrichment and diseases of aquatic organisms. We examined nutrient enrichment through the widespread practice of integrated pig-fish farming and its effects on microbiome composition of Brazilian amphibians and prevalence of the globally distributed amphibian skin pathogen Batrachochytrium dendrobatidis (Bd). This farming system drove surges in fecal coliform bacteria, disturbing amphibian skin bacterial communities such that hosts recruited higher proportions of Bd-facilitative bacteria and carried higher Bd prevalence. Our results highlight previously overlooked connections between global trends in land use change, microbiome dysbiosis, and wildlife disease. These interactions may be particularly important for disease management in the tropics, a region with both high biodiversity and continually intensifying anthropogenic pressures on aquatic wildlife habitats.

Biomarkers of meat and seafood intake: an extensive literature review

Meat, including fish and shellfish, represents a valuable constituent of most balanced diets. Consumption of different types of meat and fish has been associated with both beneficial and adverse health effects. While white meats and fish are generally associated with positive health outcomes, red and especially processed meats have been associated with colorectal cancer and other diseases. The contribution of these foods to the development or prevention of chronic diseases is still not fully elucidated. One of the main problems is the difficulty in properly evaluating meat intake, as the existing self-reporting tools for dietary assessment may be imprecise and therefore affected by systematic and random errors. Dietary biomarkers measured in biological fluids have been proposed as possible objective measurements of the actual intake of specific foods and as a support for classical assessment methods. Good biomarkers for meat intake should reflect total dietary intake of meat, independent of source or processing and should be able to differentiate meat consumption from that of other protein-rich foods; alternatively, meat intake biomarkers should be specific to each of the different meat sources (e.g., red vs. white; fish, bird, or mammal) and/or cooking methods. In this paper, we present a systematic investigation of the scientific literature while providing a comprehensive overview of the possible biomarker(s) for the intake of different types of meat, including fish and shellfish, and processed and heated meats according to published guidelines for biomarker reviews (BFIrev). The most promising biomarkers are further validated for their usefulness for dietary assessment by published validation criteria.

Genotoxicity assessments of alluvial soil irrigated with wastewater from a pesticide manufacturing industry

In this study, organochlorine pesticides (OCP) and heavy metals were analyzed from wastewater- and groundwater- irrigated soils (control samples) by gas chromatography (GC) and atomic absorption spectrophotometry (AAS), respectively. Gas chromatographic analysis revealed the presence of high concentration of pesticides in soil irrigated with wastewater (WWS). These concentrations were far above the maximum residue permissible limits indicating that alluvial soils have high binding capacity of OCP. AAS analyses revealed higher concentration of heavy metals in WWS as compared to groundwater (GWS). Also, the DNA repair (SOS)-defective Escherichia coli K-12 mutant assay and the bacteriophage lambda system were employed to estimate the genotoxicity of soils. Therefore, soil samples were extracted by hexane, acetonitrile, methanol, chloroform, and acetone. Both bioassays revealed that hexane-extracted soils from WWS were most genotoxic. A maximum survival of 15.2% and decline of colony-forming units (CFUs) was observed in polA mutants of DNA repair-defective E. coli K-12 strains when hexane was used as solvent. However, the damage of polA (-) mutants triggered by acetonitrile, methanol, chloroform, and acetone extracts was 80.0, 69.8, 65.0, and 60.7%, respectively. These results were also confirmed by the bacteriophage λ test system as hexane extracts of WWS exhibited a maximum decline of plaque-forming units for lexA mutants of E. coli K-12 pointing to an elevated genotoxic potential. The lowest survival was observed for lexA (12%) treated with hexane extracts while the percentage of survival was 25, 49.2, 55, and 78% with acetonitrile, methanol, chloroform, and acetone, respectively, after 6 h of treatment. Thus, our results suggest that agricultural soils irrigated with wastewater from pesticide industries have a notably high genotoxic potential.

Dietary and inhalation exposure to polycyclic aromatic hydrocarbons and urinary excretion of monohydroxy metabolites--a controlled case study in Beijing, China

Daily dietary and inhalation exposures to 16 parent polycyclic aromatic hydrocarbons (PAHs) and urinary excretion of 13 monohydroxy metabolites (OHPAHs) were monitored for 12 non-smoking university students in Beijing, China, during a controlled feeding experiment. The relationship between the urinary excretion of OHPAHs and the uptake of PAHs was investigated. The results suggest severe exposure of the subjects to PAHs via both dietary and inhalation pathways. Large increase of most urinary OHPAHs occurred after the ingestion of lamb kabob. Higher concentrations of OHPAHs were observed for female subjects, with the intakes of parent PAHs lower than those by males, likely due to the gender differences in metabolism. It appears that besides 1-PYR, metabolites of PHE could also be used as biomarkers to indicate the short-term dietary exposure to PAHs and urinary 3-BaA may serve as the biomarker for inhalation intake of high molecular weight PAHs.