grammar police on alert!

This is the worst grammatical mistake I have ever seen.

New Scientist:

Exposure to ultrasound while pregnant may effect brain development in the fetus, suggests a study on mice. But experts caution that it is too soon to extrapolate the findings to humans.

Maybe it isn't the worst, but it's pretty damn bad. Effecting brain development is what I'd consider a good thing, since you want to encourage brain development. The article, however, is trying to say that ultrasound may badly affect brain development, a different meaning entirely.