Dangers of Canned Tuna


I’d like to preface this entry with my strong recommendation to read “Slow Death by Rubber Duck” by Rick Smith & Bruce Lourie. I talked about reading this book for my Toxicology I class back at the end of October. I had finally gotten the chance to finish it before the term ended in December, and I really loved what I learned about the classes of common chemicals in consumer products. It also really emphasizes the point that while we cannot avoid completely the dangerous chemicals we have synthesized and incorporated into our daily life, it does not mean that we should not be aware and attempt to limit the amount of contact we have. A large amount of control can be done by checking the contents of what products we are buying.


Figure 1. “Slow Death by Rubber Duck: How the Toxic Chemistry of Everyday Life Affects Our Health” book cover.

Chapter 5: The Tuna Feast Experiment

Chapter 5 entitled “Quicksilver, Slow Death,” examines the dangers of mercury and how easily its levels are increased. The author who took this challenge, Bruce, monitored his mercury blood levels for several weeks while eating a diet consisting heavily on fish. This means a lot of sushi, sashimi, tuna steaks, tuna salads, tuna sandwiches, ect.


Figure 2. A nice, wholesome tuna sandwich.

During the tuna feasting experiment, the author was surprised to find how easily tuna levels had doubled after just 24 hours of his meals. What is even more alarming is that as the experiment went on, mercury levels continued to increase rapidly at an exponential rate, far above the “safe” level of mercury in the blood. It seemed as though mercury is easily accumulated in the body fat, but is not easily cleared out of body via metabolizing factors or excrement.  This results in a chemical build up, which consequently changed Bruce’s normal personality and mood.

Relating to My Own Life

This chapter is  is a prime example of how awareness can help prevent getting sick.  The chapter starts by quoting an actress who went on a Mediterranean diet, which was built around eating tons of fish, including tuna. She started having fits of dizziness and fainting, and later she  realized it was linked to the high mercury content due to her diet.


Figure 3. Cans of tuna…yuck.

Firstly, I think that this brings up a good point of why diets that emphasize eating only one type of food is bad. A key to a healthy life is a balance of many types of foods, and a diet could lead to a build-up of something that can harm you. In this case, it was mercury. In fact, I have had a first-hand experience with this. During my internship over my summer, I had eaten tuna with cucumbers and crackers every single day for lunch for a quick meal between lab experiments. I would attribute my headaches and ill feelings to the humid and hot weather, but when I had gotten so bad that I was going back and forth to the doctor constantly for a recurring UTI (something that has never, ever hit me before). After taking Tox I class, I now know that metals in high concentrations can act as an immuno-repressant, leaving your body highly susceptible to foreign or “bad” bacteria invasions.

Solution & Conclusion

A point they bring up in this chapter is about bioaccumulation. Larger fish live longer and eat smaller fish that also contain mercury. Because of this, large fish accumulate a lot of mercy. Being on the top of the food chain, human beings consume this large fish and get the highest dosage of the deadly mercury. Especially in a society where bigger is always better, we need to be aware of the build-up of these harmful substances in our food or else it will immediately make a large impact on our health.

Because of the biomagnification of mercury in larger fish, the authors suggest to try to eat smaller fish as suppose to larger fish as a possible preventative action.


Figure 4. Infographic of a mercury cycle

Hope you enjoyed this! If you do not have time or are not interested in reading all of “Slow Death by Rubber Duck” below is a link to chapter summaries. Perhaps they will intrigue you to pick up the book or download the eReader version.

LINK: “Slow Death by Rubber Duck” Chapter summaries


How It Works: Angioplasty 101 & New Advances

I’m literally on my last neuron it feels like. My brain power went from going at full-speed 200% to now a mere 14% for my last two finals tomorrow. So tired, but trying to stay awake using silly techniques like showering at odd times, napping in 1 hour intervals every 5 hours of studying that elapses, coffee & blog breaks, ect.

This could be my last one for a while, and very fitting, for it is my mother’s birthday, on this very cold Immaculate Conception (well, was, but I lost track of time).

Anyway, as you may or may not know, my mother is classified as a cardiac patient. She received what was then considered a new and innovative non-invasive procedure called “angioplasty” 7 years ago.It is now not considered a major procedure, where the patient is most likely discharged after 48 hours of the placement of the stent. A small needle and camera is inserted in the patient’s groin area and navigated to the affected, blocked areas.

Unfortunately for my mom though, a few months ago, even with drastic diet change and exercise, she was genetically predisposed to excess build up in her arteries and a quadruple by-pass surgery was finally performed in May. It was thankfully very successful, and she is healing quite nicely, with a few battle scars that I always tell her to wear proudly.

An article on ScienceDaily mentions that scientists see a benefit of magnetizing (oh ho! a Physics final topic!) the cells from the blood vessels. The magnetized cells are attracted to the stent that is installed in the vessel, which enables a vessels structure to remain open despite the build up of plaque. This allows the ease of blood flow to remain somewhat more normalized. The magnetization promotes the growth of tissues in a layer near the stent and prevents clot formation.

I used to be very interested in the field of cardiology (oh ho! a Human Physiology final topic!), but find myself more interested in neurology these days (another Physio exam topic). Even so, news in cardiology always intrigues me as a scientist and as a health conscious person with a line of heart disease in her family.

Even with all these wonderful advancements, always know that the best medicine is preventative: diet & exercise ahoy!