Emerging Contaminants

Knowledge gaps and opportunities for understanding water-quality processes affecting water availability for beneficial uses

“…Similarly, per-and polyfluoroalkyl substances (PFAS) have existed for decades but it is only recently that their many pathways to natural waters and their consequent widespread occurrence and potential health risk have been recognized (Ahrens and Bundschuh, 2014;Guelfo and Adamson, 2018;Sunderland and others, 2019;Ankley and others, 2021). In addition, improved analytical detection limits for CECs have led to recognition of more widespread occurrence across the Nation and awareness of the potential risk to environmental and human health caused by chemicals that are biologically active by design (Barber, 2014). Thus, the definition of CECs results in a mix of chemicals that changes with time and understanding (Barber, 2014).…”

“…In addition, improved analytical detection limits for CECs have led to recognition of more widespread occurrence across the Nation and awareness of the potential risk to environmental and human health caused by chemicals that are biologically active by design (Barber, 2014). Thus, the definition of CECs results in a mix of chemicals that changes with time and understanding (Barber, 2014). Determining the environmental fates and toxic effects of individual CECs can be challenging because they often occur as complex mixtures with complex effects (Kolpin and others, 2002;Barber, 2013;Bradley and others, 2016;Masoner and others, 2019;Battaglin and others, 2020).…”

“…The sources of CECs are as varied as the contaminants themselves, ranging from municipal wastewater to septic tanks to agricultural run-off to chemical spills. Downstream water quality is known to be degraded by treated municipal wastewater discharge (Kolpin and others, 2002;50 Water-Quality Processes Affecting Water Availability for Beneficial Uses Barber, 2014;Bradley and others, 2016;Bradley and others, 2017;Gallen and others, 2018;Battaglin and others, 2020), industrial contaminants from wastewater discharge and chemical spills (Squillace and others, 1996;Landmeyer and others, 1998;Akob and others, 2016;Zhang and others, 2016;Cozzarelli and others, 2021), and return flows from agricultural practices (Kolpin and others, 2002;Murray and others, 2010;Salimi and others, 2017;others, 2018, 2019). USGS scientists can prioritize investigations into the ever-increasing suites of new CECs, their sources and exposure pathways, and their effects on potential downstream water uses, by focusing on complex mixtures of contaminants coming from predominant source types.…”

“…In another national study, the TP desulfinyl fipronil was detected in over 90 percent of stormwater samples (Masoner and others, 2019). Thus, TPs of hydrocarbons (Bekins and others, 2016), pesticides (Mahler and others, 2021), and wastewater compounds (Barber, 2014) are ubiquitous in water, but their formation, persistence, and toxicity are poorly characterized. Gaining a better understanding of TPs is important for water assessments because overall toxicity of contaminants in water could be vastly underestimated if TPs are not also considered.…”

Effects of cooking process on the level of heavy metal accumulation in vegetables: Literature review

“…Aminopolycarboxylic acids act as a 'chelant', contain several carboxylate groups linked to one or more nitrogen atoms, and are able to form complex metal ions by forming stable heteroatomic rings (known as the 'chelate effect'). These metal complexes are stable and water-soluble (Fiorucci et al, 2002) and restrict the metal ion from normal chemical interactions [17].…”