TY - JOUR
T1 - Identification of chemicals of potential concern (COPECs) in anthropogenic wetlands of the Colorado River delta
AU - García-Hernández, Jaqueline
AU - Glenn, Edward P.
AU - Flessa, Karl
N1 - Funding Information:
We thank German Leyva-García for collection of samples, processing samples and aid in the analysis of metals, Martin Jara for the analysis of selenium, Daniela Aguilera-Márquez for sample extraction for pesticide analysis and Pedro Bastidas for the analyses of organochlorine pesticides. We thank all the participants in the Colorado River delta working group who have contributed to this work on different ways. We greatly appreciate the support of Sonoran Institute, Pronatura Noroeste and Fondo Mexicano de la Conservación for funding the sampling and analysis at the UGC-estuary and Rio Hardy and the University of Arizona who provided funds for the Cienega de Santa Clara work. And we are grateful for the comments of our two anonymous reviewers who greatly improved the manuscript.
PY - 2013/5
Y1 - 2013/5
N2 - An early step in an Ecological Risk Assessment (ERA) process is the screening of chemicals to identify those that constitute a potential risk by comparing concentrations to levels that are believed to be nonhazardous or "benchmarks". In the present study we analyzed concentrations of metals and metalloids (mercury, arsenic, selenium, and copper) as well as organochlorine pesticides in samples of water, sediment, and fish from the Cienega de Santa Clara wetland, Rio Hardy wetland, and the Upper Gulf of California-estuary. These wetlands are located in northwestern Mexico in the Colorado River delta. All contaminants analyzed were retained as Chemicals of Potential Ecological Concern (COPECs). Mercury was identified as a priority COPEC due to its potential negative effects in freshwater biota, benthic invertebrates and fish eating birds in all three study areas. Copper posed a potential high risk to Rio Hardy aquatic biota. Arsenic represented a risk to aquatic plants and to benthic invertebrates of the three areas with special concern at the Upper Gulf of California-estuary. Selenium was found at levels that could cause a slight (5.6%) reduction in avian reproductive success at the Cienega de Santa Clara and Rio Hardy, similar to the effects found at the Salton Sea. For organochlorine pesticides, DDT represented a potential high risk for aquatic biota at the Cienega de Santa Clara and Rio Hardy, DDD posed a risk for fish eating birds at the Cienega de Santa Clara, and DDE represented a high risk for fish eating birds at the Rio Hardy. In addition to these contaminants, other published studies in the area have identified chromium, lead, boron, PCBs, organophosphorous pesticides and contaminants of emergent concern (CECs) as toxic or potentially toxic for aquatic biota, benthic invertebrates, and wildlife. We recommend to follow-up with an ERA process where the actual effects of COPECs in species and plants of concern (i.e. endangered, rare, keystone species) are evaluated.
AB - An early step in an Ecological Risk Assessment (ERA) process is the screening of chemicals to identify those that constitute a potential risk by comparing concentrations to levels that are believed to be nonhazardous or "benchmarks". In the present study we analyzed concentrations of metals and metalloids (mercury, arsenic, selenium, and copper) as well as organochlorine pesticides in samples of water, sediment, and fish from the Cienega de Santa Clara wetland, Rio Hardy wetland, and the Upper Gulf of California-estuary. These wetlands are located in northwestern Mexico in the Colorado River delta. All contaminants analyzed were retained as Chemicals of Potential Ecological Concern (COPECs). Mercury was identified as a priority COPEC due to its potential negative effects in freshwater biota, benthic invertebrates and fish eating birds in all three study areas. Copper posed a potential high risk to Rio Hardy aquatic biota. Arsenic represented a risk to aquatic plants and to benthic invertebrates of the three areas with special concern at the Upper Gulf of California-estuary. Selenium was found at levels that could cause a slight (5.6%) reduction in avian reproductive success at the Cienega de Santa Clara and Rio Hardy, similar to the effects found at the Salton Sea. For organochlorine pesticides, DDT represented a potential high risk for aquatic biota at the Cienega de Santa Clara and Rio Hardy, DDD posed a risk for fish eating birds at the Cienega de Santa Clara, and DDE represented a high risk for fish eating birds at the Rio Hardy. In addition to these contaminants, other published studies in the area have identified chromium, lead, boron, PCBs, organophosphorous pesticides and contaminants of emergent concern (CECs) as toxic or potentially toxic for aquatic biota, benthic invertebrates, and wildlife. We recommend to follow-up with an ERA process where the actual effects of COPECs in species and plants of concern (i.e. endangered, rare, keystone species) are evaluated.
KW - Arsenic
KW - Colorado River delta
KW - Mercury
KW - Organochlorine pesticides
KW - Selenium
KW - Toxicological benchmarks
UR - https://www.scopus.com/pages/publications/84884590953
UR - https://www.scopus.com/pages/publications/84884590953#tab=citedBy
U2 - 10.1016/j.ecoleng.2013.04.045
DO - 10.1016/j.ecoleng.2013.04.045
M3 - Article
AN - SCOPUS:84884590953
SN - 0925-8574
VL - 59
SP - 52
EP - 60
JO - Ecological Engineering
JF - Ecological Engineering
ER -