Zürich II Statement on Per- and Polyfluoroalkyl Substances (PFASs): Scientific and Regulatory Needs

Per- and polyfluoroalkyl substances (PFASs) are a class of synthetic organic chemicals of global concern. A group of 36 scientists and regulators from 18 countries held a hybrid workshop in 2022 in Zürich, Switzerland. The workshop, a sequel to a previous Zürich workshop held in 2017, deliberated on progress in the last five years and discussed further needs for cooperative scientific research and regulatory action on PFASs. This review reflects discussion and insights gained during and after this workshop and summarizes key signs of progress in science and policy, ongoing critical issues to be addressed, and possible ways forward. Some key take home messages include: 1) understanding of human health effects continues to develop dramatically, 2) regulatory guidelines continue to drop, 3) better understanding of emissions and contamination levels is needed in more parts of the world, 4) analytical methods, while improving, still only cover around 50 PFASs, and 5) discussions of how to group PFASs for regulation (including subgroupings) have gathered momentum with several jurisdictions proposing restricting a large proportion of PFAS uses. It was concluded that more multi-group exchanges are needed in the future and that there should be a greater diversity of participants at future workshops

Conflicts of Interest in the Assessment of Chemicals, Waste, and Pollution

Pollution by chemicals and waste impacts human and ecosystem health on regional, national, and global scales, resulting, together with climate change and biodiversity loss, in a triple planetary crisis. Consequently, in 2022, countries agreed to establish an intergovernmental science–policy panel (SPP) on chemicals, waste, and pollution prevention, complementary to the existing intergovernmental science–policy bodies on climate change and biodiversity. To ensure the SPP’s success, it is imperative to protect it from conflicts of interest (COI). Here, we (i) define and review the implications of COI, and its relevance for the management of chemicals, waste, and pollution; (ii) summarize established tactics to manufacture doubt in favor of vested interests, i.e., to counter scientific evidence and/or to promote misleading narratives favorable to financial interests; and (iii) illustrate these with selected examples. This analysis leads to a review of arguments for and against chemical industry representation in the SPP’s work. We further (iv) rebut an assertion voiced by some that the chemical industry should be directly involved in the panel’s work because it possesses data on chemicals essential for the panel’s activities. Finally, (v) we present steps that should be taken to prevent the detrimental impacts of COI in the work of the SPP. In particular, we propose to include an independent auditor’s role in the SPP to ensure that participation and processes follow clear COI rules. Among others, the auditor should evaluate the content of the assessments produced to ensure unbiased representation of information that underpins the SPP’s activities

Microplastics in manure: Sources, analytical methods, toxicodynamic, and toxicokinetic endpoints in livestock and poultry

Microplastics are pollutants of serious environmental and public health concern. Although predominantly known to occur in environmental and biological matrices, emerging scientific evidence has indicated that they can also occur in fecal matter. Animal manure, both raw and treated, is usually applied on farmlands as organic fertilizer, serving as an entry point of microplastic particles into agricultural soil. The present study analyzes the literature on the occurrence of microplastics (sources and analytical methods of detection in livestock and poultry manure), their toxicodynamic, and toxicokinetics endpoints in farm animals. Based on the studies examined herein, there is a lack of harmonization in the sampling, digestion, and extraction procedures for microplastics in animal manure. Microplastics abundance was 9.02 × 102 ± 1.29 × 103 particles/kg-1 in pig, 7.40 × 101 ± 1.29 × 102 particles/kg-1 in cow, 0 to 5000 particles/kg−1 in sheep, and 129.8 ± 82.3 particles/g−1 (0.1298 particles/kg) in chicken manure. Microplastics that have been found in farm animal manure were primarily ingested from microplastics-contaminated feed and plastic mulching film attached to crop residues. However, there are other likely sources (e.g., water, soil, and air) that need to be studied carefully. Despite the limited studies on the fate of microplastics in raw manure, the weight of the currently available scientific evidence shows that they exhibit different characteristics during the treatment of manure. The previous studies were all based on composting experiments. Therefore, research on different treatment methods is required to have a profound sense and a better understanding of the influence of physicochemical properties (shape, size, type, and composition) of microplastics on their fate during manure treatment. Moreover, exposure of animals to microplastics revealed several toxicological effects but more research is needed to clearly understand the dose-response relationship, and absorption, distribution, metabolism, and elimination mechanisms with respect to other factors (microplastic sizes, shapes, polymers, types of additive, and co-contaminants)