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Investigates the consequences of the ban of meat and bone meal (MBM) and animal fat with regard to livestock feeding, cropping, ecology, economy with an inter-disciplinary approach for German and the European Union. Production and chemical composition of MBM; Potential for the use of MBM in feeding pigs and poultry; Discussion on pollution gas emissions of incineration and co-incineration as an alternative way of disposal.

Toxicokinetic-toxicodynamic (TKTD) modeling has received increasing attention in terms of the regulatory environmental risk assessment of chemicals. This type of mechanistic model can integrate all available data from individual-level bioassays into a single framework and enable refined risk assessments by extrapolating from laboratory results to time-variable exposure scenarios, based, for instance, on surface water exposure modeling (e.g., FOCUS). Dynamic energy budget (DEB) models coupled with TKTD modules (DEB-TKTD) constitute the leading approach to assess and predict sublethal effects of chemicals on individual organisms. However, thorough case studies are rare. We provide a state-of-the-art example with the standard aquatic test species Ceriodaphnia dubia and the fungicide azoxystrobin, including all steps, from bespoke laboratory toxicity tests to model calibration and validation, through to environmental risk assessment. Following the framework proposed in the European Food Safety Authority Scientific Opinion from 2018, we designed bespoke good laboratory practice-compliant laboratory toxicity studies based on test guideline 211 of the Organisation for Economic Co-operation and Development and then identified robust parameter values from those data for all relevant model parameters through model calibration. The DEB-TKTD model, DEBtox2019, then informed the design of the validation experiment. Once validated, the model was used to perform predictions for a time-variable exposure scenario generated by FOCUS. A moving time-window approach was used to perform the environmental risk assessment. This assessment method reduces uncertainty in the risk assessment while maintaining consistency with the traditional measures of risk. Environ Toxicol Chem 2024;43:2409-2421. © 2024 Syngenta Crop Protection AG. ibacon GmbH and The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC., (© 2024 Syngenta Crop Protection AG. ibacon GmbH and The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.)

Synthetic chemicals are frequently detected in water bodies, and their concentrations vary over time. Water monitoring programs typically employ either a sequence of grab samples or continuous sampling, followed by chemical analysis. Continuous time-proportional sampling yields the time-weighted average concentration, which is taken as proxy for the real, time-variable exposure. However, we do not know how much the toxicity of the average concentration differs from the toxicity of the corresponding fluctuating exposure profile. We used toxicokinetic-toxicodynamic models (invertebrates, fish) and population growth models (algae, duckweed) to calculate the margin of safety in moving time windows across measured aquatic concentration time series (7 pesticides) in 5 streams. A longer sampling period (14 d) for time-proportional sampling leads to more deviations from the real chemical stress than shorter sampling durations (3 d). The associated error is a factor of 4 or less in the margin of safety value toward underestimating and an error of factor 9 toward overestimating chemical stress in the most toxic time windows. Under- and overestimations occur with approximate equal frequency and are very small compared with the overall variation, which ranged from 0.027 to 2.4 × 10 10 (margin of safety values). We conclude that continuous, time-proportional sampling for a period of 3 and 14 d for acute and chronic assessment, respectively, yields sufficiently accurate average concentrations to assess ecotoxicological effects. Environ Toxicol Chem 2020;39:2158-2168. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC., (© 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.)

A lack of standard and internationally agreed procedures for higher-tier risk assessment of plant protection products for bees makes coherent availability of data, their interpretation, and their use for risk assessment challenging. Focus has been given to the development of modeling approaches, which in the future could fill this gap. The BEEHAVE model, and its submodels, is the first model framework attempting to link 2 processes vital for the assessment of bee colonies: the within-hive dynamics for honey bee colonies and bee foraging in heterogeneous and dynamic landscapes. We use empirical data from a honey bee field study to conduct a model evaluation using the control data set. Simultaneously, we are testing several model setups for the interlinkage between the within-hive dynamics and the landscape foraging module. Overall, predictions of beehive dynamics fit observations made in the field. This result underpins the European Food Safety Authority's evaluation of the BEEHAVE model that the most important in-hive dynamics are represented and correctly implemented. We show that starting conditions of a colony drive the simulated colony dynamics almost entirely within the first few weeks, whereas the impact is increasingly substituted by the impact of foraging activity. Common among field studies is that data availability for hive observations and landscape characterizations is focused on the proportionally short exposure phase (i.e., the phase where colony starting conditions drive the colony dynamics) in comparison to the postexposure phase that lasts several months. It is vital to redistribute experimental efforts toward more equal data aquisition throughout the experiment to assess the suitability of using BEEHAVE for the prediction of bee colony overwintering survival. Environ Toxicol Chem 2019;38:2535-2545. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC., (© 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.)

Monoclonal antibodies of both the IgG and the IgM type were purified by hydroxylapatite HPLC (HA-HPLC) under very mild conditions. The IgM type antibodies, which were isolated from ascites fluid and separated from other proteins also by means of size exclusion HPLC. It was shown that the most frequently observed disadvantage of HA-HPLC, that is the relative short life of the columns (P. Steffen (1989) GIT Fachz. Lab., Suppl. 3/89 (Chromatogr.), 50-90), is due to microbial contamination rather than lower mechanical stability. In order to monitor column performance, a test was developed based on the use of standard proteins under isocratic separation conditions. This allows a direct comparison between the respective performances of columns made from different materials, hydroxylapatite or fluoroapatite, from different sources and with different particle sizes. A problem which often occurs with HA-HPLC in the case of IgM antibody isolation, namely precipitation of the antibodies at low salt concentrations at the beginning of a chromatographic run, was avoided by adding sodium chloride to both separation buffers.

Four monoclonal antibodies against HuIFN-alpha-1 and -alpha-2 were produced by the lymphocyte hybridoma technique. The screening for monoclonal anti-IFN antibodies was performed by two different procedures permitting the detection of neutralizing and non-neutralizing antibodies. The first antibody screening in the supernatants of hybridoma clones was carried out by an immunodot ELISA using a novel chromogen, 2-bromo-1-naphthol, for the immunoperoxidase reaction. The second screening was performed with a solid-phase bioassay. The monoclonal antibodies IIG11 and IVH2 react specifically with HuIFN-alpha-1 independently of its origin, natural or recombinant. The mAb IIG11 recognizes also an epitope on a 27 kDa interferon, probably HuIFN-alpha-8. The mAb IIG7 binds to HuIFN-alpha-2 only, whereas the mAb IIB2 binds to HuIFN-alpha-2 and also to the 27 kDa interferon and to a 25 kDa interferon, not yet further characterized. These antibodies can be used successfully for immunopurification as well as for quantification of the corresponding interferons.

A trial of operative cholangiomanometry was proposed as a guide to common duct exploration to see if this technique would help in reducing the incidence of unnecessary common bile duct explorations and the incidence of retained stones. The technique for operative cholangiomanometry as modified from White is described. This method was used in 21 patients. A very close correlation between manometry and cholangiography in predicting the presence of pathology within the common duct at the time of extrahepatic biliary surgery was shown. Flow was the most accurate diagnostic parameter. Seven patients who were found to have common duct stones had both abnormal manometry and cholangiography. Fourteen patients without stones included 12 with negative cholangiography and manometry, and two in which manometry was normal but cholangiography suggested pathology. Common duct manometry and cholangiography can be used to decrease the number of unnecessary common duct explorations and the incidence of retained stones. The theory that common duct pathology will increase pressure and decrease flow rates is supported by this study. Manometry and cholangiography should be used in combination as they are additive studies. Criteria for deciding when to explore the common duct are presented.