© New Zealand Broadcasting School 2021

Christchurch children exposed to lead from petrol may have lower IQ

Ella Stokes
Petrol pump mp3h0355
NZ children exposed to high levels of lead in the 1970s and 1980s now have a lower IQ.  Wikimedia Commons

Christchurch study backs up recent findings that links high lead exposure with a lower IQ.

The Christchurch study found similar results to the University of Otago's Dunedin Study, which shows that among more than 500 children who grew up in the era of leaded petrol, have a lower IQ and social standing by the age of 38, relative to peers who had less exposure.  

Director of the Dunedin study, Professor Terrie Moffit of Duke University, said a similar study was carried out in Christchurch at the same time and it had similar findings.

She explained the Dunedin looked at lead in the children's blood, while the Christchurch study drew on information from tests of baby teeth. The results were relevant to cities all around New Zealand. 

Moffit said New Zealand lead levels were consistently higher than international standards during the 1970s and 1980s, largely due to petrol containing lead and motor vehicle exhaust fumes. Petrol with lead in it was banned in New Zealand in 1996.  

The study's participants are part of a life-long examination of more than 1000 people born in New Zealand during the 1970s and 1980s.

Moffit said there was significantly reduced risk of being exposed to lead today and people should not be worried about it.  But the study showed the importance of not being exposed to environmental pollutants.