M&D are not ostriches, unlike most everyone else who mnfrs in China (toys or otherwise). A lot of companies kind of have this whole "don't ask, don't tell" policy, where they just don't want to know what goes on. Everyone was so quick to blame the Chinese when the whole Mattell recalls started, but I blame Mattel for giving short-shrift to compliance.
M&D does proactive, (and more importantly, unannounced and frequent) compliance inspections of their factories to make sure their standards are upheld. No one cares if the Chinese standards are upheld, because those standards are so unbelievable low they're meaningless. A company making goods (again, any kind of product) in China has to get in there, roll up their sleeves, and start digging around. Which is exactly what M&D does.
Personally, I think M&D toys are kind of overpriced, but no, I do not worry about lead safety.