Thursday, January 12, 2017

Major Reduction in Intersex Fish After Wastewater Improvement

An intersex fish is packing sex organs for male and female and that plays just fine for earthworms but doesn't work worth a damn for fish.  Researchers discovered a dramatic reduction in the numbers of such fish after treatment of wastewater was improved.  (Science Daily:  Wastewater treatment upgrades result in major reduction of intersex fish)

Upgrades to a wastewater treatment plant along Ontario's Grand River led to a 70 per cent drop in fish that have both male and female characteristics within one year and a full recovery of the fish population within three years, according to researchers at the University of Waterloo.

- SD

You already know this is a caution against screwing with the EPA so there's no need to write the editorial.

Ed:  this was in Canada, not US!

Read up on the Cuyahuga River in Cleveland which may be the only one to ever get so polluted it really caught fire.  (Ohio History Channel:  Cuyahoga River Fire)

The cleanup of that river is one of the great successes of the EPA.

Inspired by the 1969 river fire, Congress was determined to resolve the issue of land pollution, not just in Cleveland, but throughout the United States. The legislature passed the National Environment Protection Act (NEPA) which was signed into law on January 1, 1970. This act helped establish the Environmental Protection Agency (EPA) which would be given the duties to manage environmental risks and regulate various sanitary-specific policies. One of the first legislations that the EPA put-forth was the Clean Water Act (1972), which mandated that all rivers throughout the United States be hygienic enough to safely allow mass amounts of swimmers and fish within the water by 1983. Since the 1969 Cuyahoga River fire the Northeast Ohio Regional Sewer District has invested over $3.5 billion towards the purification of the river and the development of new sewer systems. There is a projection that over the next thirty years the city of Cleveland will further endow over $5 billion to the upkeep of the wastewater system. The river is now home to about sixty different species of fish, there has not been another river fire since 1969, and yearly new waste management programs develop to ensure the sanitation of Cleveland's waterways.

- OHC


Returning to Canada ...

In 2007, Servos started tracking the number of intersex male rainbow darter fish in the Grand River. Intersex fish are a result of exposure to natural and synthetic hormones in the water, which cause male fish to grow eggs in their testes. At one point Servos noted the rate of intersex changes in the Grand River was one of the highest in the world.

In 2012, the Region of Waterloo upgraded the Kitchener Wastewater Treatment Plant and changed the aeration tank to reduce toxic ammonia. Within one year the proportion of intersex males dropped from 100 per cent in some areas to 29 per cent. By the end of three years, the numbers dropped below the upstream levels of less than 10 per cent.

- SD

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