Lead poisoning and birth defects in China

Just as reports of the rate of birth defects continuing to increase in China were published, we learn that UK researchers have determined that levels of lead exposure previously determined to be safe are in fact unsafe. Furthermore, most electronic waste dismantled in China is recycled back into consumer products (and sometimes, unwittingly, in food) and sold back to the industrialized world. 

China's wasteland of toxic electronics Ever noticed how stuff made in China, especially tech toys, has a specific, unhealthy smell? Though I am not suggesting that these objects are tainted with (only) lead, lead is emerging as the major pollutant in Chinese-manufactured goods. Though there are people who are suggesting that this is part of a “Manchurian Candidate”-type conspiracy, my belief is that it is only a symptom of a heavy metal pollution problems that plagues all developing nations, and particularly destinations of our tech waste, such as China and to a lesser extent India. Those suffering the most from pollution are these countries’ poorest.

What’s going’ on in China?

Everything coming out of China, from toys, paints, makeup, glazed pottery, children’s jewellery and other electronics or consumer products and even food appears contaminated with lead and possibly many other contaminants that have not even been tested for.

Not long ago, reports emerged of unsafe and unhealthy working conditions of those who melt our electronics and heavy metal waste in the open air, in makeshift furnaces in China, and of high rates of on-the-job mortality of those working to dismantle ships in India. Not long after, reports of high rates of birth defects in these areas started to appear. India and Bangladesh in particular seems to have a wide-spread arsenic contamination of the wells problem, causing alarming rates of eczema and other “skin-hardening” symptoms.

Since the beginning of the year, reports surfaced regularly about contamination in China:

[Beijing]’s birth defect rate has almost doubled in the last decade. The causes of such defects are not clear, but there are concerns they could be related to heavy pollution. A growing number of babies in China are being born with abnormalities - ranging from extra fingers and toes and cleft lips to congenital heart disease. In Beijing last year, according to Chinese officials, the rate was 170 per 10,000 births. That is significantly higher than the global average. This fits with other reports about sharp rises in birth defects across the country, in both rural and urban areas. Some provinces with large coal and chemical industries seem to have some of the highest rates.

Back in February 2009, BBC quoted the following news from China:

The coal-mining heartland of Shanxi province had the biggest problem. A 2007 commission report said the rate of defects had risen 40% since 2001, from 104.9 per 10,000 births to 145.5 in 2006. Officials blame emissions from Shanxi's large coal and chemical industry for the problems there. "The problem of birth defects is related to environmental pollution, especially in eight main coal zones," said An Huanxiao, the director of Shanxi provincial family planning agency. Mr Jiang said a child was born with physical defects every 30 seconds because of the degrading environment. Correspondents say the report suggests there is a human cost to China's rapid economic development. Researchers also blamed exposure to nitrogen dioxide, carbon monoxide and particulates for the increase. "The number of newborns with birth defects is constantly increasing in both urban and rural areas," China Daily newspaper quoted Mr Jiang as saying. "The rather alarming increase has forced us to kick off a high-level prevention plan." The commission had introduced a screening programme in the eight worst-affected provinces, Mr Jiang said.

Lead and the economy

The high rate of birth defects has caused people to get understandably upset. The government has vowed, as a result, to close down all smelters that are substandard, causing the price of lead to spike:

Sept. 4 (Bloomberg) -- Lead, the best performer on the London Metal Exchange this year, surged to the highest price in almost 16 months as China vowed to shut substandard smelters after thousands of children were poisoned.

People in China are angry “that children are involved in poisoning cases, which is why the government must take harsh measures and show it is serious about punishing offenders,” said Liu Biyuan, an analyst at GF Futures Co. The country is the world’s biggest lead producer and consumer.

The metal, used in batteries, has more than doubled this year, partly on concern that production may not keep pace with rising Chinese demand. There was a “buying panic” in the London market for lead, according to Citigroup Inc. Excessive exposure may make children less intelligent, doctors say.

Lead for delivery in three months jumped as much as 4.7 percent to $2,387 a metric ton, the highest level since May 8, 2008, and traded at $2,355 at 2:38 p.m. in Singapore. The metal rose as much as 8.8 percent yesterday after the initial report of the planned environmental crackdown.

There was “an explosive move in the market,” Jiang Donglin, Shenzhen Zhongjin Lingnan Nonfemet Co.’s research department manager, wrote in an e-mail. At least 200,000 tons of lead capacity is at risk of closure, according to Jiang. China produced about 1.947 million tons in the first seven months.

Sickened Children

The country will “strictly enforce” anti-pollution rules for nonferrous smelters, Zhou Shengxian, head of the Ministry of Environmental Protection, said yesterday in a report. China is investigating a third lead-poisoning case in the past month involving children, according to media reports.

Chinese lead makers’ shares surged today on the metal’s gain. Henan Yuguang Gold & Lead Co., the nation’s top producer, gained by the 10 percent daily limit to 18.30 yuan, and Shenzhen Zhongjin Lingnan Nonfemet added as much as 9 percent.

The supply “fears turned the market into a buying panic,” Citigroup’s David Thurtell wrote in a Sept. 3 note, referring to lead’s gain on the London Metal Exchange. China’s “smelter problems are potentially much more significant to short-term supply” than the 2007 closure of Australia’s Magellan mine, which helped to double prices, Thurtell wrote.

Global lead production was about 4.241 million tons in the first half of this year, in line with metal usage of 4.204 million tons, according to estimates from the International Lead and Zinc Study Group.

Lead producers that don’t meet environmental standards will be shut down, the ministry’s Zhou was quoted as saying in the report, sourced from the China Environment News. Potential entrants to the smelting business won’t be allowed to start output unless they meet the rules, Zhou was cited as saying.

Serious Harm

While environmental protection work had advanced in China, “conditions in our country are still very severe,” Zhou was cited as saying, highlighting new pollution problems from lead, mercury and cadmium. These had “seriously harmed the health of local residents, negatively impacting society,” Zhou said.

A routine blood test conducted on 1,000 children in Kunming, capital city of Yunnan, found 200 who had “excessive” levels of lead, the China Daily reported on Aug. 31. There are also lead-poisoning probes in Shaanxi and Hunan provinces.

Children are especially vulnerable to lead poisoning, which can hurt brain function, the World Health Organization has said. There is “no known safe blood level for children,” according to Vivian Tan, a spokeswoman for the WHO in China.

Melamine Cases

China has struggled to implement health standards at industrial and food-manufacturing plants. At least six children died in China and 300,000 others fell ill last year after drinking milk formula contaminated with melamine, a chemical used to make plastics.

Lead-acid battery production by China may jump 45 percent next year as the nation boosts alternative-energy use in transport and construction, according to an estimate last month from the largest producer, Tianneng Power International Ltd.

China’s car sales surged 31 percent to 5.37 million units in the first seven months of this year after the government cut retail taxes and began handing out 5 billion yuan ($733 million) in subsidies to boost demand.

Demand for lead is “going to keep going up, not just for bicycles, but also for cars,” according to Sept. 1 comments from Bob Takai, general manager of financial services at Sumitomo Corp. “Fundamentally, it is very strong.”

Just how bad lead really is?

Glad you asked.

First of all, there is no safe level of exposure to lead. A recent study from the University of Bristol Centre for Child and Adolescent Health and published in the Archives of Diseases in Childhood found that “the toxic effects of lead on the central nervous system are obvious even below the current so-called safe level of lead in the blood and are recommending the threshold should be halved”.

Sources of Lead

  • Lead-based paint
  • Household dust
  • Lead water pipes
  • Soil around the home
  • Paint on children's toys
  • Children's bead necklaces
  • Christmas lights
  • Lead smelters/industries

Lead levels

The Bristol researchers took blood samples from 582 children at the age of 30 months.

They found 27% of the children had lead levels above five microgrammes per decilitre.

They followed the children's progress at regular intervals and then assessed their academic performance and behavioural patterns when they were seven to eight years old.

After taking account of factors likely to influence the results, they found that blood lead levels at 30 months showed significant associations with educational achievement, antisocial behaviour and hyperactivity scores five years later.

With lead levels up to five microgrammes per decilitre, there was no obvious effect.

But lead levels between five and 10 microgrammes per decilitre were associated with significantly poorer scores for reading ( 49% lower) and writing (51% lower).

A doubling in lead blood levels to 10 microgrammes per decilitre was associated with a drop of a third of a grade in their Scholastic Assessment Tests (SATs).

And above 10 microgrammes per decilitre children were almost three times as likely to display antisocial behaviour patterns and be hyperactive than the children with the lower levels of lead in their blood.

Adverse effects

The effects of lead toxicity in children were first described in 1892 in Brisbane, Australia. 

Since then acceptable levels of lead in the blood have fallen sharply.

In 1991, the US Centres for Disease Control and Prevention, revised their level of concern for blood levels down to ten microgrammes per declitre.

The World Health Organisation estimates that globally half of the urban children under the age of five have blood levels exceeding this limit.

Professor Alan Emond, who led this study, said a third of the children in his study had levels only half of this but were still exhibiting adverse effects.

He said: "Lead in the body is one of many factors that impacts on education, but this is a reminder that environmental factors are important and paediatricians must test more children with behavioural problems for lead."

"We did our blood survey when the children were about two and a half years old.

"We think this is quite close to the peak age for lead ingestion when the children are putting everything in their mouths as they explore their environment.

"This is a normal phase that we grow out of, but for children who have developmental problems, like autism, it may go on for a longer time so they may be particularly vulnerable. "

A Health Protection Agency spokesman said: "The Agency's advice is that exposures to lead should be kept to the minimum that is reasonably practical.

"This has been the policy in the UK and of health agencies throughout the world for many years.

"Measurements have shown that levels of lead in children and adults have decreased markedly over the last two decades or more, primarily because of these policies."

An earlier study done in USA came up with similar conclusions: “World Health Organization recommends children should not be exposed to blood levels of more than 100 microgram/litre, but US scientists found increased risks at levels up to five times lower”. The Tulane University findings were published in the journal Circulation in 2006.

The researchers examined data on 13,946 adults whose blood lead levels were measured between 1988 and 1994. They also looked at death rates and cause of death for this group up to the end of 2000.

They found that the risk of death from all causes, and cardiovascular disease, increased progressively at higher lead levels.

Compared to people with a blood lead level below 19 micrograms/litre, those with a level of between 36 and 100 micrograms/litre had:

  • A 25% higher risk of death from any cause
  • A 55% higher risk of death from cardiovascular diseases
  • An 89% higher risk of death from heart attack
  • Two-and-a-half times the risk of death from stroke

Chief researcher Dr Paul Muntner said the study also found evidence that lead blood levels as low as 20 micrograms/litre were associated with a raised risk of cardiovascular death.

He said the public health implications of the findings were potentially significant, as 38% of US adults were estimated as having blood lead levels higher than 20 micrograms/litre in 1999-2002.

Dr Muntner said: "Future research is needed to identify the level of lead exposure that is not associated with major health outcomes.

"Although markedly reduced, the current blood lead levels may not be low enough, and we believe that practical and cost-effective methods for reducing lead exposure in the general population are needed."

UK measures

A spokesman for the UK's Health Protection Agency said the UK had cut lead emissions by 97% since the 1970s.

Measures had included a ban on the use of lead pipes for drinking water in new installations, and the phasing out of lead-based petrol.

However, he said there was evidence to suggest that even exposure to small amounts of lead could pose a risk - particularly to the development of children's brains.

He said: "We do not believe that any exposure to lead is entirely harmless, and it has been government policy for many years to reduce exposure wherever reasonably practical.

"As a result of these efforts, blood lead levels in the UK have fallen dramatically in recent decades and surveys indicate that the great majority of UK children are now well below the target level."

"It is reasonable to expect further reductions in blood lead levels, as older legislation continues to have an effect and newer actions - such as lowering limits for lead in drinking-water - are introduced."

Ellen Mason, a cardiac nurse at the British Heart Foundation, said: "Because lead does not stay around in the bloodstream for long it makes it difficult to tell whether it is linked to heart disease.

"Further studies are needed to establish whether a link exists and whether it would take short or long term exposure to lead to put the heart at risk."

The researchers found no association between blood lead levels and death from cancer

There is even a connection between lead and cataract. Cumulative exposure to lead increases the risk of cataracts, found a study done by the Boston’s Brigham and Women’s Hospital and published in the Journal of the American Medical Association. They “found people with the highest level of lead in their bones were most likely to develop a cataract; cataracts, the leading cause of blindness world-wide, are a clouding of the lens, the clear tissue which focuses light on to the retina”.

Despite measures to cut lead pollution, most adults have substantial levels in their bodies.

Previous research has indicated that low-level lead exposure may increase the risk of a number of chronic age-related diseases.

The Boston team investigated whether there was an association between the development of cataracts and lead levels in two bones - the tibia (shin bone) and the patella (kneecap).

Data was analysed on 642 male patients, or which 122 developed a cataract.

The researchers found that men with the highest tibia lead level were 2.7 times more likely to develop a cataract than those who recorded the lowest level of lead in this bone.

When other factors, such as smoking and diabetes were taken into consideration, the risk rose to 3.2 times that of those exposed to the lowest lead levels.

The research also found an increased risk among patients who recorded the highest patella lead levels - but the trend was not significant.

Blood lead levels, more indicative of short-term exposure levels, were not significantly associated with cataract.

Writing in JAMA, the researchers said they believe their study provides the first evidence suggesting accumulated lead exposure, such as that commonly experienced by adults in the US, may be an important, unrecognized risk factor for cataract.

Physiological cause

Researcher Dr Debra Schaumberg told the BBC News website: "There are laboratory data, including from animal studies, showing that lead can get into the lens, and that once there it is toxic.

"In particular, lead interferes with the normal oxygen balance and causes oxidative stress leading to changes in lens proteins that can affect lens clarity and transparency and thus cause cataract.

"Another possible mechanism might be that lead may also interfere with the normal calcium balance in the lens."

Dr Schaumberg said the results suggested that lead exposure contributed to 42% of all cataracts.

"If these data are relevant to other areas of the world then it seems logical that reduction of lead exposure could have a significant impact on cataract development globally."

Anita Lightstone, head of eye health for the Royal National Institute for the Blind said lead exposure was harmful for many reasons and should be avoided.

However, she said: "We would not wish people to be unduly alarmed as in a large number of cases cataracts can be removed with an operation and by use of an artificial lens, good vision can be restored.

"RNIB also recommends that everyone have their eyes tested once every two years, for early detection of eye conditions such as cataracts."

Because of how almost all the manufacturing activity in the world has migrated to China, avoiding Chinese products has become impossible, or prohibitively expensive. And if this, or nothing above is news to you, take the pollution quiz linked below – see how well you do!

Sources / More info: bbc-pb-children, bbc-low-pb, bbc-pb-cataract, bbc-beijing-birth-defects, bbc-china-birth-defects, bbc-china-pollution-disabilities, india-bangladesh-ship-breaking, /.-88% electronics-recylcing, engadget-chinas-wasteland, bbc-global-path-pollution, bbc-pollution-quiz, bloomberg-pb-surges, reuters-china-lead-checks, csm-lead-poisoning, cnn-china-lead-poisoning, edf-pb-china-dishes, wnd-china-exports-pb-poisoning,

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