Background: Finding alternative hair dyes for individuals allergic to para-phenylenediamine (PPD) has been difficult. Newer permanent and demipermanent hair dyes that have replaced PPD with para ...

Vaccines mistakenly substituted for PPD include tetanus toxoid and diphtheria and tetanus toxoids. As of March 2004, 100 patients in 21 states had been identified as receiving a tetanus toxoid ...

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