Meta-Analysis of Mass Balances Examining Chemical Fate during Wastewater Treatment

Mass balances are an instructive means for investigating the fate of chemicals during wastewater treatment. In addition to the aqueous-phase removal efficiency (Φ), they can inform on chemical partitioning, transformation, and persistence, as well as on the chemical loading to streams and soils receiving, respectively, treated effluent and digested sewage sludge (biosolids). Release rates computed on a per-capita basis can serve to extrapolate findings to a larger scale. This review examines over a dozen mass balances conducted for various organic wastewater contaminants, including prescription drugs, estrogens, fragrances, antimicrobials, and surfactants of differing sorption potential (hydrophobicity), here expressed as the 1-octanol−water partition coefficient (<i>K</i>_OW) and the organic carbon normalized sorption coefficient (<i>K</i>_OC). Major challenges to mass balances are the collection of representative samples and accurate quantification of chemicals in sludge. A meta-analysis of peer-reviewed data identified sorption potential as the principal determinant governing chemical persistence in biosolids. Occurrence data for organic wastewater compounds detected in digested sludge followed a simple nonlinear model that required only <i>K</i>_OW or <i>K</i>_OC as the input and yielded a correlation coefficient of 0.9 in both instances. The model predicted persistence in biosolids for the majority (>50%) of the input load of organic wastewater compounds featuring a log₁₀ <i>K</i>_OW value of greater than 5.2 (log₁₀ <i>K</i>_OC > 4.4). In contrast, hydrophobicity had no or only limited value for estimating, respectively, Φ and the overall persistence of a chemical during conventional wastewater treatment

Chances and Challenges of Registry-Based Pharmacovigilance in Multiple Sclerosis: Lessons Learnt from the Implementation of the Multicenter REGIMS Registry

The long-term and potential rare side effects of new immunomodulating drugs for the treatment of multiple sclerosis (MS) are often not well known. Spontaneous case report systems of adverse drug effects are a valuable source in pharmacovigilance, but have several limitations. Primary data collections within registries allow a comprehensive analysis of potential side effects, but face several challenges. This article will outline the chances and challenges of registry-based adverse event reporting, using the example of the German immunotherapeutic registry REGIMS. REGIMS is an observational, clinical multicenter registry that aims to assess the incidence, type, and consequences of side effects of MS immunotherapies. Patients treated with an approved MS medication are recruited by their physicians during routine visits in hospitals, outpatient clinics, and MS-specialized practices. REGIMS incorporates an electronic physician-based documentation in each center and a paper-based patient documentation, both at baseline and regular follow-up visits. By the end of 2019, 43 REGIMS centers were actively recruiting patients and performing follow-up documentations. The majority of the first 1000 REGIMS patients were female (69.3%), had relapse-remitting MS (89.8%), and were treated with a second-line therapy. During the implementation of REGIMS, several logistic and procedural challenges had to be overcome, which are outlined in this paper. Pharmacovigilance registries such as REGIMS provide high-quality primary data from a specific patient population in a real-world care setting and enable pharmacovigilance research that cannot be carried out using secondary data. Despite the logistic and procedural challenges in establishing a multicenter pharmacovigilance registry in Germany, the advantages outweigh the drawbacks

Development and calibration of a passive sampler for perfluorinated alkyl carboxylates and sulfonates in water

Perfluorinated chemicals (PFCs) are emerging environmental contaminants with a global distribution. Due to their moderate water solubility, the majority of the environmental burden is assumed to be in the water phase. This work describes the application of the first passive sampler for the quantitative assessment of concentrations of perfluorinated alkylcarboxylates (PFCAs) and sulfonates (PFSAs) in water. The sampler is based on a modified Polar Organic Chemical Integrative Sampler (POCIS) with a weak anion exchange sorbent as a receiving phase. Sampling rates were between 0.16 and 0.37 L d(-1), and the duration of the kinetic sampling stage was between 2.2 and 13 d. A field deployment in the most urbanized estuary in Australia (Sydney Harbour) showed trace level concentrations from passive samplers (0.1-12 ng L-1), in good agreement with parallel grab sampling (0.2-16 ng L-1). A separate field comparison of the modified POCIS with standard POCIS suggests the latter may have application for PFC sampling, but with a more limited range of analytes than the modified POCIS which contains a sorbent with a mixed mode of action