Identification of new emerging pollutants in surface water using suspect screening analysis and prioritisation strategies based on regulatory databases

Emerging pollutants (EP) have the potential to enter the water system and cause adverse ecological and human health effects while simultaneously not being covered by existing water-quality regulations. However, the existing target analysis methodology only allows the detection of a very small fraction of the substances present in wastewater samples. The new advances in high resolution mass spectrometry (HRMS) and the application of suspect screening, with a suspected screening list based on prior information but with no reference standard, greatly increases the list of substances that can be identified. The present study aims to detect and identify new, potentially hazardous pollutants based on the hypothesis that regulatory databases can assist in the prioritisation of relevant substances. Data from the Swedish Chemical Agency was used to prioritise compounds based on the occurrence on the market, the consumer tonnages, and the use pattern, among other factors. Out of the approximately 20 000 chemicals present in the database, 143 potential organic pollutants were prioritised and a screening was performed in surface water from different locations in Sweden using a LC-HRMS-based analytical approach. 21 tentative identifications were successfully performed with most substances being formerly out of the focus for environmental scientists (also not included in regulations nor monitoring programs). 16 of those substances were further confirmed with reference standard (the highest number in a study of this nature) showing the efficiency of both, the prioritisation strategy, and the suspect screening approach. Results indicate that the use of regulatory databases is a promising way to enhance identification rates as well as to identify new, potentially hazardous compounds

COVID-19 immune signatures reveal stable antiviral T cell function despite declining humoral responses

Cellular and humoral immunity to SARS-CoV-2 is critical to control primary infection and correlates with severity of disease. The role of SARS-CoV-2-specific T cell immunity, its relationship to antibodies, and pre-existing immunity against endemic coronaviruses (huCoV), which has been hypothesized to be protective, were investigated in 82 healthy donors (HDs), 204 recovered (RCs), and 92 active COVID-19 patients (ACs). ACs had high amounts of anti-SARS-CoV-2 nucleocapsid and spike IgG but lymphopenia and overall reduced antiviral T cell responses due to the inflammatory milieu, expression of inhibitory molecules (PD-1, Tim-3) as well as effector caspase-3, -7, and -8 activity in T cells. SARS-CoV-2-specific T cell immunity conferred by polyfunctional, mainly interferon-γ-secreting CD4+ T cells remained stable throughout convalescence, whereas humoral responses declined. Immune responses toward huCoV in RCs with mild disease and strong cellular SARS-CoV-2 T cell reactivity imply a protective role of pre-existing immunity against huCoV

Suspect Screening and Regulatory Databases: A Powerful Combination To Identify Emerging Micropollutants

This study demonstrates that regulatory databases combined with the latest advances in high resolution mass spectrometry (HRMS) can be efficiently used to prioritize and identify new, potentially hazardous pollutants being discharged into the aquatic environment. Of the approximately 23000 chemicals registered in the database of the National Swedish Product Register, 160 potential organic micropollutants were prioritized through quantitative knowledge of market availability, quantity used, extent of use on the market, and predicted compartment-specific environmental exposure during usage. Advanced liquid chromatography (LC)–HRMS-based suspect screening strategies were used to search for the selected compounds in 24 h composite samples collected from the effluent of three major wastewater treatment plants (WWTPs) in Sweden. In total, 36 tentative identifications were successfully achieved, mostly for substances not previously considered by environmental scientists. Of these substances, 23 were further confirmed with reference standards, showing the efficiency of combining a systematic prioritization strategy based on a regulatory database and a suspect-screening approach. These findings show that close collaboration between scientists and regulatory authorities is a promising way forward for enhancing identification rates of emerging pollutants and expanding knowledge on the occurrence of potentially hazardous substances in the environment

COVID-19 immune signatures reveal stable antiviral T cell function despite declining humoral responses.

Cellular and humoral immunity to SARS-CoV-2 is critical to control primary infection and correlates with severity of disease. The role of SARS-CoV-2-specific T cell immunity, its relationship to antibodies, and pre-existing immunity against endemic coronaviruses (huCoV), which has been hypothesized to be protective, were investigated in 82 healthy donors (HDs), 204 recovered (RCs), and 92 active COVID-19 patients (ACs). ACs had high amounts of anti-SARS-CoV-2 nucleocapsid and spike IgG but lymphopenia and overall reduced antiviral T cell responses due to the inflammatory milieu, expression of inhibitory molecules (PD-1, Tim-3) as well as effector caspase-3, -7, and -8 activity in T cells. SARS-CoV-2-specific T cell immunity conferred by polyfunctional, mainly interferon-γ-secreting CD4+ T cells remained stable throughout convalescence, whereas humoral responses declined. Immune responses toward huCoV in RCs with mild disease and strong cellular SARS-CoV-2 T cell reactivity imply a protective role of pre-existing immunity against huCoV