Possible Impact of Heavy Metal Contamination in Dairy Products


Dairy products are among the most sought-after food groups in the world. Providing nutrients to over 6 billion people worldwide, and a consistent component of many diets in developing countries. With our population continuing to rise, and calorie-rich diets seeing higher demand, it is becoming ever more crucial to safeguard the dairy industry from potential contamination and protect consumers from chemical hazards and toxic heavy metals.

There are two different categories of metals found within dairy products. Some elements, such as iron, copper and zinc, are classed as essential elements in low doses. Whereas metals such as lead, mercury, arsenic and cadmium are classed as non-essential and toxic. The presence of the latter, even at low concentrations, can lead to extremely serious consequences if consumed.

These harmful metals are common industrial air pollutants, and can aggregate in soil, water and plants, leading to their uptake into the food chain. As such, robust analytical techniques, such as inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectroscopy (AAS), are important to accurately quantify the heavy metal content in dairy items to ensure food safety and quality.

Keeping Consumers Safe

In recent years, the contamination of milk and dairy products with trace metals has become a growing concern. With the globalization of many sectors, and industries scaling up their production, the quality control processes covering the contents of complex matrices, like milk, are of increasing importance. The quality, yield and potential contamination of these products can be influenced by a multitude of things, including the animal’s genetics, it’s feed and management, as well as post-production and packaging processes.

Trace metal contamination presents potential harm to the human body and its proper functioning. Metal toxicity is dependent upon the dosage, but even in relatively low quantities, toxic elements like cadmium, arsenic and mercury have been linked to liver, kidney and renal issues. The absence of these toxins with the use of quality controls will help guarantee consumer safety.

Many different industries are scaling up production in order to meet consumer’s growing quantity demands. However, with this, there has been an increase in product recalls, in both size and regularity. This outlines the need for more robust technologies to be implemented within the supply chain in order to challenge these concerns and meet newer, more stringent regulatory standards.

From Isles to Aisles

The globalization of the dairy industry is presenting new challenges for stakeholders upholding the safety of their products. Differences in the aforementioned regulations between countries, as well as different production methods and standards, adds additional layers of difficulty to the sector. The transportation of goods between continents has opened the marketplace to new and nutritious dairy products, in particular cheeses.

However, from Missouri to Mumbai, there is little uniformity in dairy cattle farming management – differences in their feed, equipment and container types can all lead to different traces of metals. For instance, a study found higher lead content in milk from farmers who used plastic buckets than in fresh milk from aluminum milk cans, due to the toxic element leeching from previous uses.

Variation in handling from traders and processors can also impact the quality of milk and dairy products, with these products becoming susceptible to contamination from heavy metals through the materials involved in packing and the packaging process. The dairy industry, in particular, being vulnerable to lead and cadmium contamination.

Packaged goods, such as ready-sliced cheeses and yogurts, present different challenges. For sliced goods there is a risk that fragmentation of the blade can contaminate the product with metal shavings. Whereas with yogurts, a manufacturer will foil-seal to ensure the integrity of the product. Any faults with this process may also bleed a metal contaminant into a product. In both of these cases, it becomes essential for the inclusion of rigorous quality control technologies to be implemented in order to guarantee the absence of toxins, and ensure laboratories can handle these measurements.

Residue Regulations

The identification of metal presence in complex dairy matrices can be performed with pinpoint accuracy. However, with changing regulations to protect the consumer, the quantification of elements is being demanded more regularly. New and innovative solutions are required in order to ensure the quality of these products, and to check the standards are upheld throughout the production and post-production processes.

Regulatory bodies across the globe have recognized the growing concerns surrounding trace metals and toxicity, and frequently adapt standards in order to minimize the content of these elements in the food chain. Maximum limits have been established, with the International Numbering System for Food Additives (INS) and Environmental Protection Agency (EPA) giving recommendations of maximum limits allowed in dairy products. Lead residue is regulated to 1ppm, whereas cadmium – a suspected human carcinogen – has a maximum residual limit set at 0.01ppm.

The development of rapid, sensitive methods, and advances in the accurate quantification of the contents of complex matrices, continues to shape the industry. With faster and more accurate technologies, comes further scrutiny on lowering the levels of trace metals and carcinogens. To protect consumer confidence and brand reputation, it becomes ever more important employ the gold standard of technology in dairy processing laboratories.

Skimming the surface

In one of the world’s largest and most competitive industries, supplying uncontaminated, premium dairy produce can boost a brand’s reputation and ensure consumers remain confident and safe. As demand for increasingly inventive dairy products continues to grow, it is vital for food labs to utilize robust metal testing technologies to increase efficiency. By implementing advanced solutions, dairy labs can ensure safe and high-quality products - from the first batch, to the last.


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