Mercury Poisoning from Fish
Many of us love eating fish, be it the sushi or the shark; however, while we enjoy the meat of these marine animals, there is a hidden threat in their fat cells and muscles. We don't realize it (or even if we do, we eat anyway) that the body of the fish absorbs a toxic substance that is equally poisonous for both, humans and the fish. Yes, methylmercury is the poisonous substance that is mostly absorbed by the fish. The increasing mercury in seas and rivers due to water pollution has raised serious health concerns. Some scientists believe that the doses of mercury in fish are not harmful whereas few others have claimed that the higher levels of mercury in fish, are for sure, harmful.
Though no one has been able to come out with conclusions that can correctly state the threshold level of mercury doses in fish, the Bureau of Health Environmental Toxicity Program has collected data and has categorized the fish in two levels; one that contain high levels of mercury and the other containing very less levels of mercury. Fish that are low in mercury content are recommended for eating. Some fish, like tilefish, swordfish, king mackerel and shark come under the category of high mercury containing fish. Various other shellfish and fish containing lower levels of mercury are tuna, halibut, catfish, oysters, shrimp, crab king etc.
The research carried out was based on a certain number of samples of the fish collected from various sources. This research was just from a sample of hundreds of fish, so we can't confidently say that if we eat the fish of low mercury content, we are saved from the threat of mercury poisoning. It's all just a possibility. However, preferring fish low in mercury content is the safest route to take, in case you include fish very often in your diet.
Symptoms
Levels of mercury in the environment increase due to the discharge of gases from chemical and power plant industries. The mercury from the air is deposited into water and there the bacteria convert the element mercury into a dangerous compound methylmercury. The chief reason behind mercury poisoning from fish consumption is the presence of toxic methylmercury. The effects of mercury poisoning depend on the extent of mercury consumed and the time for which the person has been exposed to mercury. It can cause permanent damage to the brain and kidneys. When absorbed by the skin, mercury and its compounds can trigger allergic reactions. If ingested in the body, mercury causes severe renal and gastrointestinal disorders. In pregnant women, infants and children, it hampers the neurological development of the brain. During the pregnancy period, if the mother suffers from mercury poisoning then it can lead to the poor development of the child and he may be born with some defects like poor memory and damaged brain cells. Some more symptoms of this poisoning from fish are as follows:
- Vision impairment.
- Numbness in hands and feet.
- Poor coordination of muscles.
- Problems related to speech, walking and the neurological system.
- Muscle weakness.
- Mood swings and erratic behavior.
- Mental imbalance.
In urgent cases of mercury poisoning, it is best to seek hospital care or consult a doctor. The medical experts will perform diagnostic tests and try to expel the poison from the body, by providing various treatments. Some of the treatment methods for mercury poisoning are chelation therapy, activated charcoal, gastric lavage etc. It is to be understood that higher doses of mercury consumption can lead to death, so it is important to take precautions. It is important that we use water filters in our home, for drinking and cooking purposes. Besides mercury spills, consuming freshwater fish is the leading cause of mercury poisoning. Pregnant women and children must especially limit the consumption of fish in their diet. According to experts, a child under 6 years of age must not be fed a little tuna fish more than once a month. For children between 6 to 12 years old, the limit of consumption is twice a month. Even adults must follow a strict regime of one fish meal per week. Identifying the possible sources of mercury poisoning and taking adequate precautionary measures can go a long way in reducing the risk of mercury poisoning.
Many states in the US collect data about local fish and provide information about the safety levels of mercury consumption in fish. With the increasing amount of toxicity in the air and water, scientists are worried about the rising concentration of mercury in the fish. The world has seen the threats of Minamata disease in Japan in the past few decades. Minamata disease, a severe mercury poisoning case, first affected Japan in 1956 and has been the cause of deaths of several people. While the US government takes adequate measures to prevent the threats of mercury poisoning, we should exercise control over our diet and possibly avoid consuming too much fish in our diet.
