Lake Erie: The Dead Lake Of North America - 1960's-70's Part 1

Earlier I discussed the dire situation in which Lake Erie found itself in the 1960's-70's, and specifically the role that phosphorus had played in said degradation of the lake.  While the excess of phosphorus entering Lake Erie in the 1900's was responsible for a great deal of the troubles the lake faced, it was merely one of many serious issues plaguing the lake.  Aside from the abundance of algae in the lake and the accelerated eutrophication it caused, the lake was subjected to pollution in various other forms.  The most devastating of these other forms of pollution consisted of sewage and industrial discharge which made it's way into the lake in immense quantities on a daily basis.


Lake Erie's Most Serious Threats During The 1950's-1970's

Numerous industries around Lake Erie and in the surrounding areas would use nearby waterways which connected to the lake, or even the lake itself to dispose of their waste.  Due to this, the lake quickly became the region's industrial dumping ground.  By the 1960's, it became commonplace to find high concentrations of pollutants in the lake, such as:

- Mercury.  A toxic heavy metal known to attack the brain and nervous system of organisms that have ingested it in high quantities.
- DDT.  A harmful pesticide known to cause deformities and reproductive failures in animals.  It wasn't until 1972 that the pesticide was banned in Ontario and the majority of the United States.
- PCBs.  PCBs, or Polychlorinated Biphenyls very persistent chemicals; they do not deteriorate easily on their own, and they are very difficult to destroy.  They were used for decades in the 1900's as ingredients in many industrial materials, and were banned in 1977.

Mercury + Its Effects On Human Health 

A Can Of DDT

Warning Sign Indicating The Presence Of PCBs

Many of these chemicals and pollutants may not seem like a threat to humans, but once they reach the aquatic environment, there are many ways in which they can make their way into our bodies and cause harm.  Mercury for instance, poses a threat because after having made it's way into the lake, it made it's way into the fish.  And so, people then have to be careful about ingesting fish due to the mercury which may be found inside them.  It is true however, that an individual contaminated fish would not contain enough mercury to cause any real harm to humans.  But collectively, if an individual were to eat contaminated fish often enough, for a long period of time, then the mercury will take its tole on said individual's health.  

 

Sources:
1. http://ohioseagrant.osu.edu/_documents/publications/FS/FS-046%20Lake%20Erie%20water%20quality%20past%20present%20future.pdf
2. http://clevelandhistorical.org/items/show/58#.UsmlxPRDuXs
3. http://www.hc-sc.gc.ca/hl-vs/iyh-vsv/environ/pcb-bpc-eng.php
Images:
1. Mercury http://www.periodictable.com/Elements/080/
2. Mercury health effects http://pubs.usgs.gov/fs/1995/fs216-95/
3. DDT http://jiminmontana.com/2012/01/15/environmentalism-the-green-religion-of-dehumanization/
4. PCBs http://www.thecompliancecenter.com/store/ca/labels/pcb/lb-pcb1aus.html