Nobody is testing chemicals on kids. This website states that the study is just gathering information on toddlers - in homes where pesticides are sprayed. How many people in Australia have there house sprayed for insects, or use fly-spray - nobody is monitoring their babies development or urine pesticide residues....
Most of the chemicals you are allowed to have sprayed now barely even kill the insects, let alone us!
I can't see any problem with this study. I'm sure that there will be people up in arms about it, there always is.