The Hong Kong Consumer Council (COC) has reported widespread contamination in locally available dried goji berries (often called wolfberries), a popular health food staple. A testing program conducted between August and September 2022 on 27 samples—sourced from supermarkets, pharmacies, and specialty food stores—revealed that every single product contained varying levels of heavy metals, while nearly 70% also harbored pesticide residues. Though the majority of findings adhered to stringent Hong Kong regulatory standards, the detection of multiple contaminants across the board raises crucial questions regarding agricultural sourcing and cumulative health risks for consumers.
Heavy Metals Found in All Samples
The investigation uncovered that all 27 tested samples contained heavy metals. Specifically, lead was detected in 21 of the products. While most levels were compliant with regulatory limits, two brands—”Shangpin Ready-to-Eat Ningxia Goji Berries” and “Yupin Huang Goji Berries”—showed lead concentrations nearly reaching the local maximum statutory allowance established under the Food Adulteration (Metallic Contaminants) Regulation. These specific findings have been referred to the Centre for Food Safety (CFS) for further review. Chronic exposure to lead is a known public health concern, particularly for children, as it can impair neurological and intellectual development.
Other heavy metals detected in the samples included cadmium, which was present in all products, and trace amounts of arsenic and chromium in a smaller subset of samples. Despite these widespread findings, the Council noted that all detected heavy metal levels were ultimately in compliance with current Hong Kong legislation.
Concerns Over Widespread Pesticide Residues
Beyond metallic impurities, residue from various pesticides was a significant finding, appearing in 19 of the 27 samples tested. The samples collectively contained 14 different types of pesticides.
Of particular concern, two samples—”FRESH Goji Berries” and “Shaoxiangyuan Ready-to-Eat Goji Berries”—contained concentrations of chlorfenapyr and chlorothalonil, respectively, that exceeded the maximum residue limits set by the European Food Safety Authority (EFSA). However, the COC also clarified that these levels still fell below the requirements stipulated in Hong Kong’s Pesticide Residues in Food Regulation for similar vegetable categories.
The testing further highlighted the prevalence of multi-residue contamination. One product, “Hart Goji Berries,” tested positive for seven different types of pesticides, while three other brands contained five types. The Council emphasized that the cumulative effect of consuming multiple chemical residues simultaneously, often termed the “cocktail effect” or synergistic action, could pose risks not accounted for by examining individual residues alone.
Consumer Takeaways and Safety Recommendations
The price range for the dried goji berries varied dramatically, from $9.0 to $64.3 per 100 grams, indicating that price is not necessarily a guarantee of purity or quality. Encouragingly, tests confirmed that none of the samples contained prohibited artificial food colorings or mycotoxins, such as aflatoxins and ochratoxins.
For consumers looking to minimize exposure to contaminants while enjoying the widely recognized health benefits of goji berries, the COC highlighted several products that scored 4.5 out of 5 stars in the overall assessment, often featuring organic certification:
- Wai Yuen Tong Ningxia Goji Berries (Organic Ingredients)
- Sunfood Super Foods
- Green Common Organic Premium Goji Berries
- Livi Green Organic Ready-to-Eat Goji Berries
- Slowood Organic Goji Berries
These findings underscore the need for greater transparency and improved quality control practices throughout the agricultural supply chain for imported health foods. The COC advises consumers to thoroughly rinse goji berries before consumption to help reduce superficial residues, and to diversify their diet to avoid excessive reliance on any single-source food item. Ultimately, while regulation provides a safety floor, consistent vigilance and continuous testing remain essential for safeguarding public health in Hong Kong’s dynamic food market.