China's Pollution: The Birth Defect Angle

I work in international adoption.  One of the biggest changes in the last ten years is the precipitous drop in the number of infants with no identified medical needs available for adoption from China.  This is a hugely contentious topic within the adoption community, and I'll spare you most of it.
 
However, along with the disappearance of children with no identified medical needs, we have seen a huge increase in the number of children with identified medical needs.  Every month, I place children (from 9 months to 14 years) who have cleft lip and/or cleft palate; missing fingers, hands, toes, parts of arms or legs; malformed internal organs; genetic disorders; etc.
 
While any country with a population as large as China's will have some number of children born with birth defects, there are persistent rumors that the horrendous pollution in China has led to a huge increase such births in China.  This, combined with the one-child policy, has led to orphanages being filled with special needs children, some of whom have very complex and difficult medical needs.  In addition, children remaining in families often have less obvious medical issues that affect their ability to live full lives.
 
[I wonder what] effect that this is going to have on China as it continues to develop....
 
I lived in [a former Soviet bloc country] in the early 90s.  Environmental degradation was a huge issue, and one that everyone I met, whatever their politics, agreed had contributed to the collapse of the communist system.  I bet the party officials in Beijing know that very well.

From another reader, this link to an article on the possible relationship between certain forms of pollution and autism. And from a technically trained reader who has been living and working in China:

I suspect that breathing and eating all that heavy metal as children growing up would definitely retard brain development....

It is not hard to believe, if the vegetables they ate spent the entire season grown in soil and air laden with heavy metals, the water they drank is contaminated with metals and VOCs [Volatile Organic Compounds], and the air the breath is full of PM2.5 dust which can pass through the alveoli sacs into the blood stream, and through the blood/brain barrier, directly into their growing brains.  Certainly, we are aware of how heavy metals retard brain development...

One must wonder, in addition to mild retardation, what other personality disorders can result from this disruption in normal development of the brain, from birth onward.  Are they building a society where certain psychological disorders are the norm?  Are we seeing this mass disorder and mis-diagnosing it as just the modern Chinese culture?

To be entirely clear here: I don't personally know whether heavy-metal and other pollutant burdens in China are in fact causing birth defects and cognitive disorders. I'm not in a position to judge the scientific literature. But I do know that the pollution level in China is terrible; that (even) the Chinese press is sounding the warning about the effects; and that in other parts of the world toxins have of course been shown to cause physical and mental defects and diseases. This is a very big problem in China, perhaps even bigger than people there yet know.