• Vets at Home

Marv and mercury toxicity

Marv is a 15 year old cat. His owner initially described that he had a facial twitch a few years ago. At the time we ran a blood test, noted his kidneys weren’t functioning optimally, but there was nothing to explain the twitch. Life carried on.




More recently Marv’s owner called to investigate a limp. An odd limp that came and went. We investigated and didn’t find anything notable at the time. Marv’s owner mentioned that the twitches were much more frequent and getting worse. She wanted to know what was causing the twitches. On a hunch I decided to run a hair tissue mineral analysis on Marv. The results are below.



As you can see Marv has severe mercury toxicity. Marv also has significant amounts of arsenic and aluminium. Even though Arsenic and aluminium are near or in the reference range the body as no known biological need for any of these elements. If we consider the total amount of heavy metal load that Marv is dealing with we can imagine stacking the height of the load of arsenic, mercury and aluminium on top of each other and then you can appreciate that his total load will be off the top end of the chart.


Mercury is a known neurotoxin and is the likely cause of Marv’s facial twitch. In people mercury is associated with tourettes syndrome, neurological problems, multiple sclerosis, kidney issues, pain in extremities (could this be the cause of Marv’s odd limp?) amongst other symptoms. Mercury is stored in the kidney, liver, brain, thyroid and fat tissue and can damage all of these tissues. It also impairs the energy production and detoxification pathways in the body, leading to further accumulation of toxins.


So where is Marv getting all this Mercury? Well Marv is a tuna addict. Large fish bioaccumulate mercury. Mercury can also be found in insecticides and fungicides which reach our pets by eating of grains in pet food. Mercury can also be found in some vaccines injected into our pets. The aluminium is likely coming from aluminium tins containing the tuna and other cat food. Cats can get arsenic from rice in pet food and also other grains that have been sprayed with fungicides and pesticides.


Marv is now on a gentle detoxification program. We have added some binders to help to pull the mercury out of his system, some vitamins to support neurological function, amino acids to support detoxification pathways, and have discussed some diet tweaks though Marv is resistant to this. I don’t like to push diet changes in senior cats so we have to work with what Marv is comfortable with.


Ideally, we need to stop our pets gaining a heavy metal load in the first place. We need to look carefully at what they are being fed and sources of contamination. We also need to look closely at the necessity of other toxins that our pets are getting – if their bodies are busy detoxifying other chemicals then they can’t get rid of heavy metals at the same time. A species appropriate diet generally also reduces the toxic burden both through reduced toxin accumulation in food and also providing supportive nutrients to assist with detoxification.