"The danger was certainly there when they were using DDT," he said.
But there are still too many obstacles preventing nations that need it from using DDT when appropriate.
In the old days, they used DDT, which gives you an idea of what you're up against.
But if it used DDT, it could protect people for $1.70 per person per year.
It is up to countries to decide whether or not to use DDT.
If you insist on using DDT, the only thing you can do is stop.
I think there are situations in which you could use DDT surgically.
"We have got to stop pressuring countries to stop using DDT," he said.
"They only want us to use DDT on poor, rural black people," he says.
Accordingly, countries are listed as using 0 or "some" DDT.