The Effects Of Heavy Metals On The Food Cycle

The presence of heavy metals is widespread in the environment and can also penetrate the food cycle. Environmental contamination, from soil and water, is the primary source, but they can enter via food processing as well. The traces of heavy metals in food, including plant origin products, and animal origin food is a major concern in the current world.

Fish seems the most contaminated

Fish is one of the most affected products by heavy metal contamination. This is because heavy metals tend to be bioaccumulative in the food chain. When heavy metals get accumulated in the water, fish consume them and store them in their bodies throughout their lives. Henceforth, heavy metals reach those consumers who intake fish. Certain heavy metals are highly toxic regardless of their forms and can be immensely hazardous to the environment and human health in general.

Dangers concerning heavy metal contamination

The hazards of heavy metals loom large as they are not biologically or chemically degradable. Once they are released into the environment because of industrial and mining activities, in particular, they can remain in the environment for years to come, polluting the soil, air, and water, and accumulating in organic tissues, and plants. The concentration of heavy metals increases as they move up the food chain. Mercury, lead, cadmium, nickel, and zinc seem to be the most dangerous forms of heavy metals in food. Aluminum and arsenic are two relevant metals from the point of toxicity and are studied along with heavy metals.

Impact of mercury

Mercury is considered one of the highly toxic heavy metals. It is accessible naturally in the metallic form as mercury, or as mercury salts. When present in the air, it is highly volatile and can get absorbed through the skin and even lungs, thereby impacting long-term health. Inhaling mercury is said to be the most dangerous because it gets inside the human body, and remains for a long period.

One must understand that mercury is not found naturally in food items. But, instead, it enters the human body via fish. Fish is known to consume mercury in large quantities, as it is one of the most common heavy metals found in rivers and seas. Furthermore, mercury can also enter the bodies via animal and plant products especially those that accumulate in the soil. Usually, mercury is generated via human activities like solid waste burning, mining, use of agricultural pesticides and fertilizers, discharge of wastewater, and so on.

The effect of lead

Lead is yet another heavy metal that can be highly harmful to human health. The metal is often used in residential buildings in the form of paints, plumbing pipes, chemicals, metal alloys, pesticides, and putties. It is one of the heavy metals in food that contaminates the most. Lead can easily enter the body via fruits, vegetables, meat, seafood, etc., and cause harm to a large percentage of the population. Tobacco smoke is also one of the pollutants that contain a high amount of lead. Thus, it is suggested that one must avoid smoking because even passive smokers (individuals who are in the ambiance of the direct smokers) can get contaminated with harmful lead traces, despite not smoking.

Cadmium and its effect

Cadmium is mostly a by-product or residual product of zinc. It is generated mainly from the process of zinc refining. The crust of the earth contains cadmium, which is absorbed by the organic materials forming the soil. This is in itself a great threat to humans because the deposits of heavy metals are absorbed by the organic components of the soil. This is passed into plants, which often form a significant part of the human and animal diets. Mushrooms, freshwater fish, shellfish, potable water, and dried algae are some of the food lists that are more prone to cadmium contamination. Furthermore, smokers, as well as passive smokers are also exposed to cadmium to a great extent. People living close-by factories and waste dumps are also susceptible to atmospheric cadmium exposure. Workers at metal refineries are heavily exposed to cadmium and other heavy metals, thereby posing dangerous health hazards.

Impact of copper

Cooper is one such mineral that offers great benefits to human health if the right measure is consumed. When it is consumed in high doses, it is considered a heavy metal and can incur disorders like kidney and liver problems, anemia, stomach issues, and several other severe health problems. It is one of the heavy metals in food that gets sourced from residential pipes, and cookwares used. It can easily pass to cooked food items, and water. Copper is used in massive quantities across the residential and commercial sectors. Henceforth, copper exposure has become so high in recent years.


When the rightful measure of nickel is consumed, it is beneficial in red blood cell formation. But when people intake, inhale or absorb in excess quantities, it can be highly toxic, depending on the quantity. It can impact the nose, larynx, lungs, prostate, and even the heart. Furthermore, nickel is used in steel alloys and is also present in the food chain and the environment in low traces. Nickel poisoning can be harmful to health, and it is a major concern because of the high contamination in the food chain.

Arsenic and aluminum

When heavy metal contamination is discussed, lighter elements like arsenic and aluminum must be considered as well. Arsenic is one of the most common causes of metal poisoning in adults. It is not a metal, but a metalloid, with both metallic and non-metallic properties. Industrial processing involving glasses, and chemicals generate arsenic, which passes into water supplies, thereby contaminating marine life.

Due to the toxicity of aluminum, it is considered as one of the heavy metals that can impact health negatively. When one is suffering from excess aluminum intake, he/she can suffer muscle weaknesses, body aches, seizures, slow development and growth in children, confusion, speech problems, and so on.


Heavy metals in food lead to contamination which can affect the health of humans tremendously. Heavy metal poisoning when not addressed timely can be fatal too. Henceforth, a systematic approach must be practiced to ensure the risks associated with heavy metal contamination are either reduced or eliminated.