Below is a link to the site of a parent whose child's vitiligo repigmented.
http://vegan-omics.com/ev/
Here is an excerpt from the page:
<< Four different surveys of the safety of our milk supply were conducted by
independent researchers between 1987 and 1989. The results were not
comforting, unless you like antibiotics and other veterinary drugs in your
dairy products. The studies found between 63 and 86 percent of milk samples
to contain sulfa drugs, tetracyclines, and other antibiotics. These surveys
embarrassed the FDA so much that the agency finally got around to conducting
a survey of its own. Despite using outdated methods that cannot detect small
quantities of the dangerous drug sulfamethazine, a March 1988 FDA survey
found sulfamethazine in 74 percent of the samples tested.
This finding was particularly disturbing. Sulfamethazine is a sulfa drug
that is a suspected human carcinogen.>>
Siobhan