Site-Specific Profiles of Estrogenic Activity in Agricultural Areas of California’s Inland Waters

Abstract

To evaluate the occurrence and sources of compounds capable of feminizing fish in agriculturally impacted waterways of the Central Valley of California, water samples were extracted and subjected to chemical analyses as well as in vitro and in vivo measurements of vitellogenin in juvenile rainbow trout (Oncorhynchus mykiss). Among the 16 sites sampled, 6 locations frequently exhibited elevated concentrations of estrogenic substances with 17beta-estradiol equivalents up to 242 ng/L in vitro and 12 microg/kg in vivo. The patterns of activity varied among sites, with two sites showing elevated activity only in vitro, two showing elevated activity only in vivo, and two showing elevated activity in both assays. Sequential elution of solid-phase extraction (SPE) disks followed by bioassay-guided fractionation was used to characterize water samples from the two locations where activity was observed in both bioassays. The highest estrogenic activity was observed in the most nonpolar fractions (80-100% methanol eluent) from the Napa River, while most of the activity in the Sacramento River Delta eluted in the 60% methanol eluent. Quantitative analyses of SPE extracts and additional HPLC fractionation of the SPE extracts by GC-MS/MS and LC-MS/MS indicated concentrations of steroid hormones, alkylphenol polyethoxylates, and herbicides that were at least 1-3 orders of magnitude below bioassay 17beta-estradiol equivalent calculations. Given the different patterns of activity and chemical properties of the estrogenic compounds, it appears that estrogenic activity in these agriculturally impacted surface waters is attributable to multiple compounds. Further investigation is needed to identify the compounds causing the estrogenic activity and to determine the potential impacts of these compounds on feral fish.

Life Histories, Salinity Zones, and Sublethal Contributions of Contaminants to Pelagic Fish Declines Illustrated with a Case Study of San Francisco Estuary, California, USA

“…Concentrations of PBDE in tissues of striped bass increased 4-fold, from ∼400 to ∼2,000 pg g −1 lipid, between 1997 and 2003 (Hoenicke et al 2007). Many of these compounds, which mimic natural endocrine hormones, can affect reproduction of wild fish (Kidd et al 2007;Lavado et al 2009b). However, few endocrine disruptors are monitored in the Estuary (Hoenicke et al 2007).…”

Combined effects of estrogenic chemicals with the same mode of action using an estrogen receptor binding bioassay

“…They are emitted from a variety of sources and seldom exist individually in any environmental compartment, leading to the combined adverse effects on organisms. There have been a number of surveys measuring either the estrogenic activity by use of bioassay, or concentration levels of the estrogenic substances by chemical analysis in water samples (Beck et al, 2006;Lavado et al, 2009;Mahomed et al, 2008;Matthiessen et al, 2006). To bridge the two measurements, concentrations could be transformed into biological activity using the estrogenic relative potency (REP).…”

Evaluation of the Estrogenic and Osmoregulatory Impacts Of Exposure to 4-Nonylphenol Pollution in the Estuarine Arrow Goby, Clevelandia Ios

“…Marine invertebrates including mussels (Mytilus californianus), oysters (Crassostrea gigas), and ghost shrimp (Neotrypaea californiensis), and fishes including arrow gobies (Clevelandia ios) and staghorn sculpins (Leptocottus armatus) from several of California's estuaries have exhibited some of the highest recorded tissue burdens of 4-NP documented worldwide (Diehl et al, 2012). The arrow goby is an ideal candidate for examining the negative effects of 4-nonylphenol on endocrine, reproductive, and osmoregulatory function because it is a common benthic inhabitant of Pacific coast bays and estuaries where it regularly comes in to physical contact with sediments rich in organic material where 4-NP can accumulate (Lavado, 2009;Blackburn and Waldock, 1995;Garrison and Hill, 1972;Ying et al, 2002;Sharma et al, 2009). Arrow gobies range in North America from British Colombia, Canada to Baja, Mexico (Eschmeyer and Herald, 1983) and occupy intertidal mud flat habitats where they forage over the benthos during high tide but take refuge in the burrows of mud-dwelling invertebrates such as the ghost shrimp N.…”

“…Because the arrow goby is a common benthic inhabitant of Pacific coast bays and estuaries where it resides in the burrows of mud-dwelling invertebrates, it is regularly in physical contact with estuarine sediments rich in organic material where 4-NP can accumulate and persist for decades (Lavado, 2009;Blackburn and Waldock, 1995;Garrison and Hill, 1972;Ying et al, 2002;Sharma et al, 2009). Arrow gobies collected from Morro Bay, California, by Diehl and coworkers (2012) were found to have 4-NP tissue concentrations a full magnitude (10x) higher than that found in the surrounding sediment.…”

“…This goby occupies the burrows of polychaete worms and shrimp at low tide, where it is in contact with low oxygen sediments rich in organic material where NP can accumulate and persist for decades (Lavado et al, 2009). Diehl and coworkers (2012) documented mean NP tissue burdens up to 40,100 ngg -1 lipid weight in arrow gobies in estuaries of California, USA.…”