BP has committed crimes against humanity, flora and fauna. Citizen activism is responsible for revealing these horrors because the government has been complicit in the cover up.
Professional chemists, private citizens, and academics (none of which are exclusive categories) have conducted independent testing. Unlike BP payed "researchers," these independent tests are revealed to the public, complete with methodology and results.
Science aint science until the results are published for peer scrutiny. That means that BP funded research is not in fact scientific.
Independent lab results are now available and they find dispersant in Gulf waters 30 days and more after BP claims dispersants were discontinued.
Discussions can be found at Alexander Higgins blog and the Intel Hub.
Evidence is also accumulating that the combination of corexit (dispersant) and oil is more dangerous than oil alone. See the full discussion at Washington's Blog.
It is difficult to maintain a lie when the public gets activated.