Source-Newsmedical.net
A recent study published in the Frontiers in Nutrition journal has revealed concerning levels of heavy metals in cocoa-based consumer products in the United States. Conducted over eight years, the study highlights the potential health risks posed by the presence of lead, cadmium, and arsenic in cocoa products, which are commonly consumed for their health benefits due to their high polyphenol content.
Cocoa products, particularly dark chocolate, are at risk of heavy metal contamination due to the proximity of cocoa fields to various pollution sources. Previous studies have detected these harmful metals, but the extent of contamination has remained unclear until now. Cadmium exposure, for instance, has been linked to serious health issues such as cardiovascular disease, kidney failure, cognitive decline, diabetes, cancer, and osteoporosis, emphasizing the importance of food quality monitoring, especially for vulnerable populations like young children and pregnant women.
Study Methodology and Analysis
The researchers analyzed 72 cocoa products from various sources, including third-party internet shops, manufacturer websites, and physical stores, between 2014 and 2022. The products, which were either locally sourced or imported from Europe, were tested for cadmium, arsenic, and lead using strict threshold values based on California’s Proposition 65 maximum acceptable dosage levels (MADLs). These levels are set at 0.50 micrograms (µg) for lead, 4.10 µg for cadmium, and 10 µg for arsenic per day.
To determine the heavy metal concentrations, samples were digested using trace metal-grade acids and then analyzed through inductively coupled plasma-mass spectroscopy (ICP-MS). The study employed multivariable linear regressions to evaluate the influence of specific and third-party certifications on metal concentrations, while also assessing the impact of the year of purchase on contamination levels. Additionally, Welch’s T-test was used to explore the relationship between organic certification and metal content.
A new study shows some dark chocolate products contain heavy metals
Findings and Implications
The study’s findings revealed that 43% of cocoa products tested exceeded the permissible levels for lead, while 35% exceeded the limits for cadmium. No samples exceeded the arsenic threshold. Notably, 97% of the products fell below the lead cutoff values set by the United States Food and Drug Administration (FDA). The average lead and cadmium levels in the products were 0.6 µg and 4.4 µg per serving, respectively, both surpassing Prop 65 MADLs. However, the median levels were lower, suggesting that outliers significantly influenced the results.
Despite these findings, the study concluded that for most individuals, consuming a single serving of these cocoa products may not pose significant health risks. However, consuming multiple servings daily, in combination with other sources of heavy metals, could increase exposure beyond safe levels. Organic cocoa products were found to contain higher cadmium levels than conventional dark chocolate, raising concerns about the safety of organic certifications.
The study also noted a decline in heavy metal contamination in samples from 2016, 2019, and 2022 compared to those from 2014, particularly concerning lead levels. Nonetheless, the researchers stressed the need for improved food monitoring and further research into cumulative heavy metal exposure from dietary sources to better protect public health.
