In this interview with Robert F. Kennedy Jnr. the lawyer explains how he became interested in the subject of mercury in vaccines and what he found out about how vested interests in the United States have influenced which vaccines end up recommended by the government.
If you are a New Zealand parent, please note that in general, the mercury-based preservative thimerosal has been phased out of vaccines that are on the NZ market. However a study published in 2010 did find a small amount of mercury in the vaccine Infanrix-hexa (on the NZ schedule for babies aged 6 weeks, three months and five months) was found to contain a very small amount of mercury in a study that was published in 2010. (See: http://www.ncbi.nlm.nih.gov/pubmed/20391108 )
You can check the ingredients of any vaccine on the NZ market by typing in the vaccine name or the disease name into the search box at this link http://www.medsafe.govt.nz/profs/datasheet/dsform.asp
The interview is here: