Analysis of information sources in references of the Wikipedia article "둘신" in Korean language version.
... Notice to manufacturers and distributors of foods and drugs containing artificial sweeteners. Chronic-toxicity studies conducted by the Food and Drug Administration show/ that the artificial sweeteners dulcin (also known as sucrol, or 4-ethoxy-phenylurea, or paraphenetolcarbamide) and P-4000 (also known as l-n-propoxy amino4-nitrobenzene) cause injury to rats when fed at relatively low levels for approximately 2 years ...'