LTCDS caused EMS in individuals consuming such supplements remains widespread in the epidemiological, medical, and nutritional communities, even though no impurity with such toxicity has ever been identified. At least three dozen deaths are attributed to EMS and the ingestion of LTCDS. Our systems analysis of EMS based on Boolean-logic, keyword-based computer searches of peer-reviewed literature disclosed correlations between eosinophilia (elevated circulating eosinophil levels), myalgia (muscle pain), and compromised histamine degradation. Both eosinophilia and myalgia are conditions associated with excessive histamine activity. Our search revealed that consumption of tryptophan supplements leads to enhanced levels of formate and indolyl compounds, several of which impair histamine degradation and thus have the potential to prolong the latent effect of histamine. In light of our findings, the assumption that microimpurities in LTCDS cause EMS is unwarranted.

Smith, M. J., and Garrett, R. H. "A heretofore undisclosed crux of eosinophilia-myalgia syndrome: Compromised histamine degradation." Inflammation Research 54 : 435-450 (2005).

Smith, M. J., and Garrett, R. H. "Part II. Eosinophilia-Myalgia Syndrome: correlations between compromised histamine degradation, eosinophilias and myopathies." Inflammation Research 56 : S08-S09 (2007).

Smith, M. J., and Garrett, R. H. "Part III. Keyword-based, Boolean-logic driven data-mining discloses correlations between additional idiopathic conditions, occlusive vascular diseases such as tropical endomyocardial fibrosis with unexplained eosinophilia, and 'histamine dysmetabolism'. Inflammation Research 57 : S01-S02 (2008).