Identifying further chemicals of emerging arctic concern based on ‘in silico’ screening of chemical inventories

• Published in: Emerging Contaminants
• Main Authors: Muir, Derek, Zhang, Xianming, de Wit, Cynthia A., Vorkamp, Katrin, Wilson, Simon
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2019
• Subjects: Arctic
• Online Access: https://pure.au.dk/portal/en/publications/36088540-10ca-4eea-b7f4-4d6d66298440; https://doi.org/10.1016/j.emcon.2019.05.005

In the past 12 years several studies have screened lists of thousands of chemicals available in the in-dustrial chemical inventories of the European Union, the USA and Canada with the goal of identifying andprioritizing chemicals which are persistent (P), bioaccumulative (B) and toxic (T). Most studies haveselected chemicals based on whether their predicted P and B properties and their long-range transportpotential exceed guideline thresholds for evaluation of persistent organic pollutants (POPs). A major goalof this study was to review this recent literature on computer-based or‘in silico’screening for POPs. Asecond goal was to review other approaches forfinding previously unidentified chemicals of concernincluding targeted and non-target analytical approaches that might use lists of suspect chemicalsdeveloped from‘in silico’screening studies. Eight studies were reviewed along with several others whichexamined the screening process and its uncertainties. From these studies we assembled a list of 3421chemicals, after removing duplicates and substances already on the Stockholm Convention on POPs.About 52% of these were halogenated, while 48% consisted of a broad range of non-halogenated organics.This list was then further analysed by calculating an overall“POPs score”for transport and accumulationin the Arctic for each substance using predicted partition coefficients, overall persistence, transfer effi-ciency, and bioaccumulation factor. A shorter list of twenty-five substances was developed based on theirPOPs score ranking. These substances had not been previously analysed in environmental media butwere nevertheless on current or recent chemical inventories indicating significant commercial use.