Exposure to industrial chemicals can severely damage brain development among children.
In a paper published by two researchers Grandjean and Philip Landrigan of New York's Mount Sinai School of Medicine who studied the effects of chemical exposures on brain development for many decades have identified at least 202 industrial chemicals that cause such disorders.
Roughly half of the chemicals are in common use, but very few have been tested to determine their impact on brain development, according to the researchers.
They noted that of the industrial chemicals known to be toxic to the human brain, only five -- lead, mercury, arsenic, PCBs (polychlorinated biphenyls) and toluene -- have been proven to cause damage to the developing brain, according to the online edition of health magazine WebMD.
These chemicals have been identified not because they are necessarily more dangerous than the others, but because they have been studied the most, they contend.
"The few substances proven to be toxic to human neurodevelopment should be viewed as the tip of a very large iceberg," they wrote in the paper.
Lead and mercury are among the few chemicals that are now strictly regulated to protect children. But regulation came long after the dangers were first recognized.
Lead-based paint was first linked to sickness in children more than a century ago, but lead was not removed from paint and gasoline in the US until the late 1970s and early 1980s.
"Despite those early pediatric warnings, the largely unchecked use of lead in petrol, paints, ceramic glazes, and many other products through much of the twentieth century caused continued risk of lead poisoning," the researchers wrote.