Human Rights Watch said Wednesday Chinese officials in provinces with heavy industrial pollution are restricting access to lead testing or even falsifying test results and denying children treatment.
Human Rights Watch accused officials in four provinces -- Henan, Yunnan, Shaanxi and Hunan -- of trying to cover up the extent of lead poisoning among local children, including limiting their access to blood tests.
"Local authorities are ignoring the urgent and long-term health consequences of a generation of children continuously exposed to life-threatening levels of lead," said the study, entitled: "My Children Have Been Poisoned: A Public Health Crisis in Four Chinese Provinces."
"Children with dangerously high levels of lead in their blood are being refused treatment and returned home to contaminated houses in polluted villages," it added.
Excessive levels of lead in the blood are considered hazardous, particularly to children, who can experience stunted growth and mental retardation.
Rapid industrialisation over the past 30 years has left China, the world's second-largest economy, with some of the world's worst water and air pollution, stoking widespread environmental damage and public-health scares.
HRW said test results are sometimes withheld from victims and their families, while children with high lead levels in their blood are denied care or simply instructed to eat cleansing foods like apples, garlic, milk and eggs.
Family members and journalists seeking information about the problem are intimidated, harassed and ultimately silenced, the report added.
"Such actions violate Chinese law and condemn hundreds of thousands of children to permanent mental and physical disabilities," it said.
Earlier this month, more than 600 people in China, including 103 children, were found with high and sometimes dangerous levels of lead in their blood, state media said.
The adult victims worked at factories that process tinfoil in Shaoxing county in the coastal province of Zhejiang, and some of their children have also been affected, the China Daily newspaper reported.
In May, authorities in Zhejiang detained 74 people and suspended work at hundreds of factories after 172 people, including 53 children, fell ill due to lead.
Nearly 1,000 children tested positive for lead poisoning in the central province of Henan in 2009 with local smelting plants found to be responsible.
The Chinese government has enforced environmental regulations aimed at curbing pollution and protecting public health in recent years.
But enforcement has been uneven and little has been done to reduce lead levels in villages that are already heavily contaminated, HRW said.