Endocrine disruptors from agricultural pesticides?

A study finds that percentage of agricultural lands in three watersheds correlates with testicular oocytes (eggs) in male smallmouth bass.  A correlation between testicular oocytes (TO) was found with estrone, a naturally occurring hormone.  There is no correlation between actual pesticides used was not studied.  Testicular oocytes were not found in two species of suckers.An article in the journal Environmental Monitoring and Assessment covered samples from 16 locations in three major river drainages (Delaware, Susquehanna and Ohio).  Fish samples were taken by electroshock during summer (low flow periods) between 2007 and 2010. Grab samples of water and sediment were taken concurrently.  Subsequently, water samples were taken during high run off periods by polar organic chemical integrative samplers (POCIS) and semipermeable membrane devices that could collect and concentrate potential contaminants that were below normal detection limits.  Endrogenicity was estimated by bioluminescent yeast endrogen screen.

The desired sample size was 10 male and 10 female.  That was not always achieved.  Estrone, a naturally occurring hormone was the only positive chemical correlation. There was no correlation between TO and being upstream or downstream of a waste water plant.  A cumulative effect was alluded to by the authors.  There was lower occurrence in Ohio, which also had the lower percentage of agricultural land.  The assumption is that the problems are caused by eggs developing in contact with sediment, which has some concentration of chemicals with estrogenic activity.

The study seems be along the lines of a earlier study by FWS and has gotten some press play (here and here.)  And, of course, there is a cry for more pesticide reporting by farmers.  The type agriculture is not considered or even pesticides that might be used in the drainage.  Other than estrone, there seems to be no correlation between pesticides and response.  It seems to be one of those studies that interesting and gets folks all excited about chemicals.

The abstract is below.

Fishes were collected at 16 sites within the three major river drainages (Delaware, Susquehanna, and Ohio) of Pennsylvania. Three species were evaluated for biomarkers of estrogenic/antiandrogenic exposure, including plasma vitellogenin and testicular oocytes in male fishes. Smallmouth bass Micropterus dolomieu, white sucker Catostomus commersonii, and redhorse sucker Moxostoma species were collected in the summer, a period of low flow and low reproductive activity. Smallmouth bass were the only species in which testicular oocytes were observed; however, measurable concentrations of plasma vitellogenin were found in male bass and white sucker. The percentage of male bass with testicular oocytes ranged from 10 to 100 %, with the highest prevalence and severity in bass collected in the Susquehanna drainage. The percentage of males with plasma vitellogenin ranged from 0 to 100 % in both bass and sucker. Biological findings were compared with chemical analyses of discrete water samples collected at the time of fish collections. Estrone concentrations correlated with testicular oocytes prevalence and severity and with the percentage of male bass with vitellogenin. No correlations were noted with the percentage of male sucker with vitellogenin and water chemical concentrations. The prevalence and severity of testicular oocytes in bass also correlated with the percent of agricultural land use in the watershed above a site. Two sites within the Susquehanna drainage and one in the Delaware were immediately downstream of wastewater treatment plants to compare results with upstream fish. The percentage of male bass with testicular oocytes was not consistently higher downstream; however, severity did tend to increase downstream.

2 responses to “Endocrine disruptors from agricultural pesticides?

  1. There is no greater threat to the environment than “organic” pesticides which lack the sophistication of synthetic pesticides. Also organic fertility management – which consists largely of composted manure – poses just as much of a threat to the environment, along with human health, as the use of synthetic ammonium nitrate (Nitrogen) does.

    But the reason we never discuss these threats from organic agriculture is to because organic farming barely comprises a percentage point or two of our total agricultural land base in America. Most USDA-certified-organic food is imported from countries like China, Mexico and Argentina, so the problems caused occur elsewhere.

    Out of sight, out of mind. This is the mindset of organic activists opposed to modern, science-based farming in America.

    • Even more so as approved “organic” fungicides include copper sulphate and other metal ions! What kind of half-life does that have in the soil?

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