The recent comprehensive safety testing of common cooking oils by the Hong Kong Consumer Council (HCC) has underscored persistent concerns about processing-related contaminants in the local food supply. The investigation, which analyzed 50 market-available cooking oil samples, revealed that three-fifths (30 samples) contained glycidyl esters and 3-monochloropropane-1,2-diol (3-MCPD) fatty acid esters (3-MCPDE), compounds linked to potential health risks in laboratory animals.
The HCC collected the samples—encompassing 13 different oil types, including extra virgin olive, avocado, coconut, peanut, and blended oils—from supermarkets and department stores between late 2021 and early 2022. While the presence of these contaminants was widespread, the HCC affirmed that all tested samples remained below the current maximum limits established by the European Union (EU), offering a degree of reassurance to consumers.
Understanding the Contamination Source
The detected chemical compounds, 3-MCPDE, are generally formed when oils are subjected to high temperatures, typically above 160 degrees Celsius, during the refining and deodorizing processes. Once consumed, the body can hydrolyze these esters in the gastrointestinal tract, releasing the toxic substance 3-MCPD.
International food safety experts, including the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (JECFA) and the European Food Safety Authority (EFSA), have cited concerns based on animal studies. Long-term exposure to high doses of 3-MCPD has been shown to potentially harm kidney function, the central nervous system, and the male reproductive system in test subjects.
Currently, Hong Kong does not have specific local legislation regulating the maximum content of 3-MCPD or its fatty acid esters in edible oils, differentiating its approach from the EU, which has strict thresholds for these substances.
Assessing Health Risk and Safety Margins
Despite the high percentage of contaminated samples, the HCC advises that for the average consumer, the risk remains low. Toxicological assessments by JECFA and EFSA establish acceptable daily intake limits for 3-MCPD. Based on the limit set by JECFA (4 micrograms per kilogram of body weight) and EFSA (2 micrograms per kilogram of body weight), a 60-kilogram adult would need to consume significant quantities daily to exceed these benchmarks.
For instance, the oil sample with the highest concentration of 3-MCPDE—Carrington Farms’ “Coconut & Avocado Cooking Oil Blend,” measured at 1,900 micrograms per kilogram—would require the 60kg adult to consume approximately 127 grams (for JECFA limits) or 64 grams (for EFSA limits) of the oil every day over a long period. Unless an individual maintains an extremely high-fat diet, normal consumption levels are unlikely to pose immediate health risks, according to the HCC.
Irregular Findings Prompt Further Scrutiny
A notable finding of the study was the detection of 3-MCPDE in three samples labeled as either extra virgin olive oil or cold-pressed oils. These types of oils are traditionally processed at low temperatures, minimizing the risk of forming these heat-induced contaminants. EU regulations and previous research indicate that non-refined, cold-pressed oils should be free of 3-MCPDE.
The presence of the contaminant in these “low-temperature” labeled products—specifically Palermo’s “Organic Extra Virgin Olive Oil First Cold Pressed,” Prolife Organic’s “Organic Wild Cold Pressed Camellia Seed Oil Unrefined,” and CanBest’s “Organic Cold Pressed & Wild Camellia Oil Extra Light”—raises potential concerns over compliance with the Trade Descriptions Ordinance. The HCC has referred these three cases to the Customs and Excise Department for immediate follow-up investigation.
Consumer Takeaways: Identifying Clean Oils
As part of the initiative to provide actionable information, the HCC released a list of edible oils that achieved a perfect score in the overall safety assessment, meaning they were deemed free from these specific processing contaminants. Consumers prioritizing oils without detectable levels of these compounds can look for these options:
Extra Virgin Olive Oils:
- Carbonell “Aceite de Oliva Virgen Extra”
- TESCO “Extra Virgin Olive Oil”
- Filippo Berio “Extra Virgin Olive Oil”
- Borges “Extra Virgin Olive Oil Cold Extraction Original”
Other Uncontaminated Varieties:
- Grove “Extra Virgin Cold Pressed Avocado Oil”
- La Tourangelle “Avocado Oil”
- Bio Planète “Organic Coconut Oil Virgin First cold pressed”
- Primo “Organic Sunflower Seed Oil Cold Pressed”
- Clearspring “Organic Rapeseed Oil (Unrefined, Cold Pressed)”
While the overall safety risk remains low, the findings highlight the importance of careful labeling and processing practices in the global edible oil industry. Consumers are encouraged to review the full list of HCC findings to make informed decisions about their dietary choices.