WHO sets tolerable limits for melamine
When the news on melamine contamination of baby formula broke this year, experts were actually at loss as to what to do because there were health-based guidance on melamine at that time. You see, melamine was initially thought to be relatively harmless, an industrial chemical of low toxicity.
A search in the Hazardous Substances Data Bank (HSDB) , for example, gave me this result:”melamine itself does not seem to be important industrial hazard except if decomposed by heat.” In addition, thousands of people are exposed to melamine in the work place with no reported permanent health problems of toxicity. The most serious health effects observed were “allergic and irritative dermatitis“.
So why had melamine suddenly become toxic to cause illness in more than 50,000 babies? It seems that a big factor in its toxicity is in combination with another chemical called cyanuric acid, which is a by-product of water disinfection and may thus be present in tap and swimming pool water. A study conducted by the US FDA revealed that “although melamine and cyanuric acid appeared to have low toxicity when administered separately, they induced extensive renal crystal formation when administered together. The subsequent renal failure may be similar to acute uric acid nephropathy in humans, in which crystal spherulites obstruct renal tubules.”
Mind you, this doesn’t exonerate the perpetrators at all. This is not the first time that melamine contamination was observed to cause health problems. In 2004 and 2007, many house pets suffered from renal failure which was eventually linked to melamine in pet food. It is therefore quite known that melamine is not as harmless as originally thought to be. Adding melamine to milk formula misleadingly increases its protein content and is a deliberate and irresponsible act that should be punished severely. Another thing to consider when deciding if you will breastfeed.
Earlier this month, experts at a World Health Organization (WHO) meeting have finally come up with guidance on melamine. They have finally established “a tolerable daily intake (TDI) for melamine.” Melamine shouldn’t be in food at all but the chemical is so ubiquitous that contamination is sometimes unavoidable. Without our being aware of it, we are exposed to minute amounts of melamine every day, which are present in fabrics, formica counter tops, and kitchen melaware.
Here are the experts’ recommendations:
TDI for melamine is at 0.2 mg/kg body weight. This means that a person weighing 50 kg can tolerate 10 mg melamine per day. This TDI, however, applies to melamine alone and not in combination with cyanuric acid. A different TDI for the combination needs to be set as soon as the enough data is available.