November 12, 2024

Monique Nguyen 

11th Grade

Fountain Valley High School

Introduction

These days, everybody is worried about the type and quality of food that they intake on a day-to-day basis. Well, add metal contaminants in food to the list of things to watch for. By definition, heavy metals are chemical metals and metal compounds that have an adverse effect on human bodies. Unsurprisingly enough, ingesting small concentrations of heavy metals is quite common because metals can accumulate and leave residue on foods and beverages. Major common foods that are known for higher metal content are fish, shellfish, rice, wheat, mollusks, mushrooms, fruits, wine, meat, vegetables, chocolate, etc. Even canned baby food has been proven to include high metal levels!

Heavy metal accumulation can occur through the food cultivation process, like farming, or the environment, where there is a plethora of contamination from industry exhaust and pollution. Some foods are contaminated through storage and processing; animals that ingest toxic waste could be a source of contamination as well. But naturally, it’s inevitable that metals appear in a small percentage of consumer food; after all, metals and metalloids like zinc, cobalt, mercury, arsenic, iron, lead, copper, cadmium, nickel, and chromium commonly occur in both the natural environment, like the soil and water, and the urban environment, such as through cookware and water pipes. 

Health Risks

If humans are ingesting toxic heavy metals through eating and drinking every day, how would it affect the human body? Does such a small presence even have an effect? Due to the overwhelmingly large presence of heavy metals and risk factors of contamination, ingestion in small quantities is unavoidable for the average consumer. In reality, some heavy metals like zinc and nickel can promote health benefits and are necessary for the human body. However, ingesting toxic metals does pose a concernable health risk when ingested at abnormally high levels or with high accumulation over a prolonged period of time. There is a margin of exposure or MOE that indicates two things for consumers: the scale of exposure for a population and the scale of exposure for an individual at which a small dose causes health deterioration. As a comparison of those two factors, higher MOEs for toxic heavy metals are generally more safe.

Traces of heavy metals are usually much too small to pose a sizable health concern to the average individual due to product restrictions, though some health reports suggest that accumulation limits are exceeded at times. Additionally, age, tolerance, health history, and individual characteristics should also be considered before contributing adverse health to metal consumption. But generally, ingesting a huge quantity of heavy metals may lead to abnormalities and dysfunction as they become oxidized when they enter the body and bond with protein molecules or enzymes. With these bonds, metals are able to travel throughout the body and interfere with multiple organs. Typically, accumulation of toxic heavy metals in the body can occur in many ways, such as through the respiratory tract, digestive tract, bones, urine, and feces; with the latter, it is easier for the body to rid itself of such metals in comparison to accumulation in the respiratory system or bones, which can reach the blood faster.

As a generalization, different metals pose different health risks. For example, studies conducted by the European Food Safety Authority prove that arsenic ingestion is correlated to skin defects and cancers. Nickel affects the lungs, larynx, and nasal system with more severe cases compromising the heart while too much of copper can cause stomach problems and anemia. Lead poisoning is extremely dangerous in developing countries, causing anemia, harming hemoglobin production, introducing nervous disorders and hypersensitivity, inducing memory loss, and causing various similar defects before death. Chromium III damages the kidneys and liver, targets the nerves and circulatory system, and can induce ulcers or skin problems. High ingestion of Chromium VI is even more serious, potentially causing cancer by reforming cell genetic material. Toxic heavy metals cause biological system degeneration, accelerate cancerous processes and emulate symptoms comparable to major diseases. Especially for children, such metals can impair brain development as well as behavioral and cognitive functions, which creates long-term detrimental health effects.

Conclusion

Because heavy metal accumulation commonly occurs through a variety of human processes and soil contamination, there are ways to decrease the amount of metal consumption. Modern technology and procedures like chemical precipitation, coagulation, and electrodialysis are examples of ways to reduce product contamination. But, though the U.S. has such an advanced urban society, such processes are not ideal due to their high-performance costs and exceptional difficulty in effectuating. Currently, researchers are still attempting to discover more cost-effective and efficient ways to manufacture foods without high traces of toxic heavy metals and decrease the health risks for humans worldwide. The World Health Organization (WHO) and other federal health agencies additionally set limits for the maximum quantity of such metals available in consumer products. For the time being, increasing consumer awareness is the most optimal way to decrease individual metal overconsumption.