Week 7–Something Fishy about the Seafood Industry: Watch out on What You Eat! 

Recently, the Food and Drug Administration (FDA) of the United States has been alerted that detectable amount of formaldehyde (which is known to the public as “formalin”) contaminated frozen fish was found at national grocery retailers in Greensboro, North Carolina. Usually, some fish species naturally contain a trace level of formaldehyde as one product of their metabolites. However, this metabolic product is produced in such small amount that it is considered undetectable. The laboratory confirmed formaldehyde positive result of these frozen fish indicated that formaldehyde has been intentionally added. It is later discovered that these formaldehyde contaminated fish products were originated from China and Vietnam.

Formaldehyde, which is not commonly used in North America, is rather routinely exploited as a perseverative for fish in some Asian countries. Research (Sotelo et al., 1995) has shown that formaldehyde can prevent fish protein denaturation during frozen storage, keeping the flesh fresh for a much longer time. This is ideal for long distance shipping and trading—for instance, exporting fish and fish products from Asia to North America.

In addition, this is not the first and only time that fish and fish products that originate in China and Vietnam are formaldehyde contaminated. In 2013, however, formaldehyde was also identified from frozen fish products in grocery stores in Raleigh, NC, according to Food Safety News (2013). These formaldehyde contaminated fish also originated from China and Vietnam, and they constitute up to 25% of the entire seafood imports from these two countries.

Moreover, besides China and Vietnam, other Asian countries also have issues with formaldehyde application to seafood and fishery industry. Bangladesh (Rahman et al., 2015) for example, has long been suffering from formaldehyde adulteration on their fish products. According to the World Health Organization (WHO) (Liteplo, 2002), fish products have naturally occurring formaldehyde found in their flesh that ranges from 1 to 20mg/kg fish. However, the mean formaldehyde concentration in locally harvested fish in Bangladesh was 118.6mg/kg fish, about 6 times higher then the suggested value by WHO. This data strongly indicates that formaldehyde was intentionally added to the fishes, as unprocessed fish would not contain formaldehyde in such high concentration.

The health risks associated with formaldehyde exposure are complicated. According to the National Cancer Institute (NCI, 2010) short-term health effects from formaldehyde exposure include watery eyes, nausea, skin irritation, and etc. Long-term exposure to formaldehyde can significantly increase the chance of getting cancer. Especially, it can increase the risks of acquiring leukemia and brain tumor.

Although not as frequently reported as other food safety related concerns, formaldehyde adulteration in fish and fish products is still a potential threat to public health. Its occurrence might be relatively rare, but its complication can be devastating. Especially in Asian countries, where the population density is high but the economical development is low, limited public resources can make the treatment of formaldehyde exposure hard. Therefore, it is essential that the governments of corresponding countries take serious responsibility, carefully monitor their food production systems, making sure no unqualified products slip through.

• Sotelo, C., Pineiro, C., & Perezmartin, R. (1995). denaturation of fish proteins during frozen storage – role of formaldehyde. Zeitschrift Fur Lebensmittel-Untersuchung Und-Forschung, 200(1), 14-23.
• Imports and Exports: How Safe is Seafood From Foreign Sources? | Food Safety News. (2013, November 10). Retrieved November 15, 2015, from http://www.foodsafetynews.com/2013/11/imports-and-exports-how-safe-is-seafood-from-foreign-sources/#.ViQNtyBViko
• Rahman, S., Majumder, M., Ahasan, R., Ahmed, S., Das, P., & Rahman, N. (2015). The extent and magnitude of formalin adulteration in fish sold in domestic markets of Bangladesh: A literature review. International Journal of Consumer Studies. doi:10.1111/ijcs.12238
• International Program on Chemical Safety, Liteplo, R. G., & W. H. Organization, (2006). Concise international chemical assessment document, number 40: Formaldehyde World Health Organization (WHO).
• Formaldehyde and Cancer Risk. (2011, June 10). Retrieved November 15, 2015, from http://www.cancer.gov/about-cancer/causes-prevention/risk/substances/formaldehyde/formaldehyde-fact-sheet