Various species of fish collected and tested at the Niagara River were found to have human antidepressants, and remnants of other drugs in their system, according to researchers.
Niagara Fish Is Medicated
FACT: If you're eating fish from this source, your fish is most likely medicated.
Consider this for a moment. When you take any kind of medications whether prescription or over the counter, these medications work on your system then are eliminated from your body in your urine or stool (poop). Both of these are flushed down the toilet into the sewage system and goes for treatment at the water treatment plant. The treatment plants were never designed to remove these drugs
Active ingredients and metabolized remnants of Zoloft, Celexa, Prozac and Sarafem — drugs that have seen a sharp spike in prescriptions in North America — were found in 10 fish species. Diana Aga, professor of chemistry at University at Buffalo, says these drugs are found in human urine and are not stripped out by wastewater treatment. 
...remnants of Zoloft, Celexa, Prozac and Sarafem were found in 10 fish species [Read now...]
Now here's the kicker. The fish are swimming in this water 24/7 and so the drugs are entering them from the water. The Niagara River feeds water into Lake Ontario. The population of medicated folks from Toronto and the Greater Toronto Area(GTA) are all using their toilets daily. Their waste water also goes into Lake Ontario. Can you guess where this is going?
Toronto's drinking water comes from Lake Ontario through intake pipes that are one to three kilometres away from shore and at a depth of 15 metres. This configuration minimizes the potential for onshore events such as heavy rainfall adversely affecting finished water quality. 
This is another reason to give up eating fish and go vegan. Also, we all need to be mindful of our drinking water. You owe it to yourself to eat high quality foods and drink water the way nature intended it.