Researchers at the University of Otago claim that lead exposure may result in loss of intelligence and lower occupational standing. People in New Zealand actually exhibit the exact same situation, according to a renowned Dunedin study. Back in 1972, Kiwis have experienced one of the highest leaded gasoline levels in the world.

Lasting for about a decade, the toxic era continues to affect the people of New Zealand up until today. Apparently, those who lived between the 1970s and the 1980s had lower IQ levels compared to those who were not exposed to lead. Also, they tend to have lower-skilled jobs than their parents or their own children.

According to New Zealand Herald, leaded petrol was only completely phased out in 1996. Now, out of the more than 1000 Dunedin participants, the study found out that 565 were damaged by the chemical. It further noted that lead levels in the blood are higher in childhood while the loss of IQ happens in adulthood.

The participants were part of a life-long research featuring individuals born between 1972 and 1973. From infancy, these samples have been regularly assessed for cognitive skills. It was when they turned 11 that the experts from the University of Otago took the blood samples. The loss of intelligence, meanwhile, appeared when the respondents reached the age of 38.

Science Daily explained that the ones carrying over 10 micrograms of lead per deciliter of blood at age 11 had IQ levels that are 4.25 lower than those with lesser lead. For the record, the figures were based on the report by Duke University. The study also noted that for every 5 micrograms increase of blood-lead content, a person loses around 1.5 IQ points. The average contamination recorded for the test samples was 10.99 micrograms.

Sadly, none of the respondents has been identified as safe. While previous politicians failed to ban lead petrol until it was too late, future public servants may refer to this study for public health. The toxin may be present in all neighborhoods since it comes from car exhausts, paints, and old pipes found in poorer families.