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Published Date: 2009-08-21 08:00:10
Subject: PRO/MBDS> Lead poisoning - China (02): Shaanxi
Archive Number: 20090821.2956

LEAD POISONING - CHINA (02): SHAANXI
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Date: Thu 20 Aug 2009
Source: Bangkok Post, Agence France-Presse (AFP) report [edited]
<http://www.bangkokpost.com/news/health/152185/number-of-kids-poisoned-by-lead-in-china-rises>

Number of kids poisoned by lead in China rises
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The number of children affected by lead poisoning blamed on a
smelting plant in north China has risen to over 850, state media said
Wednesday [19 Aug 2009].

A total of 1016 children in Shaanxi province's Changqing township
were tested, and 851 were found to have excessive lead levels in
their blood -- more than 170 of which were hospitalised, the official
Xinhua news agency reported.

This represents a significant increase from the 615 children
initially reported to be suffering from lead poisoning.

Villagers stormed the smelter Monday [17 Aug 2009], smashing trucks
in anger at the case. The plant has been ordered to close.

The lead levels in the blood of the children tested ranged from 100
milligrams to more than 500 milligrams per litre, compared with
normal levels of between zero and 100 milligrams.

A reading of more than 200 milligrams is considered hazardous, with
children more vulnerable to lead poisoning, which can harm the nervous system.

--
Communicated by:
PRO/MBDS
<promed-mbds@promedmail.org>

[The newswire above reports on a significant increase in the number
of lead poisoning cases in China's Shaanxi province. According to the
newswire, 851 children were found to have excessive lead levels in
their blood while the latest report of lead poisoning in Shaanxi
province, dated 10 Aug 2009, indicated only that "more than 300
children" were affected with lead poisoning (see prior PRO/MBDS
posting lead poisoning China: Shaanxi 20090812.2874).

Lead poisoning can cause learning disabilities, behavioral problems,
and mental retardation. At very high levels, lead can cause seizures,
coma, and even death (1,2). According to Centers for Disease Control
and Prevention (CDC), approximately 250 000 US children aged 1-5
years have blood lead levels greater than 10 micrograms of lead per
deciliter of blood, the level at which CDC recommends public health
actions be initiated (see <http://www.cdc.gov/lead/default.htm>).

For individuals with high current blood lead levels (BLLs) (more than
45 micrograms per deciliter), chelation therapy can be effective at
reducing the total lead body burden. However, only CaNa2EDTA (calcium
disodium versenate) is appropriate for chelation while Na2EDTA
(disodium ethylenediaminetetraacetic acid) is not (see
<http://www.atsdr.cdc.gov/csem/lead/pbmanage_therapy2.html>).

In 2002, the new Occupational Diseases Prevention and Control Act was
passed in China, with new provisions specifically for regulatory
enforcement. The national occupational exposure level (OEL) for lead
in China is set at 250 milligrams per litre (the 2002 Act). However,
a study presented a summary from 618 papers of lead exposure levels
and lead poisoning at workplaces in China reported in the Chinese
medical literature between 1990 and 2005 and still the lead poisoning
rates were above 30 percent (3).

Existing data suggest that lead poisoning may be widely pervasive as
a result of rapid industrialization and the use of leaded gasoline.
Children residing in industrial and busy traffic areas had average
BLLs of 21.867.9 microgram per deciliter. The percentages of BLL
values above 10 microgram per deciliter, which is the definition of
lead poisoning in children, ranged from 64.9 percent to 99 percent.
The link between low-level lead exposure and deficits in IQ,
neurobehavioral development, and physical growth is remarkably
consistent without exception in several retrospective pilot studies
in China (4).

The sources of exposure, incidence, trends, control measures,
treatment options, and preventive approaches of childhood lead
poisoning vary strikingly, especially in developing countries,
compared with the United States. The phasing out of lead from
gasoline is a critical 1st step in decreasing worldwide blood lead
concentrations. However, many focal sources that can cause lead
poisoning remain, such as, lead from flour mills, lead-glazed
ceramics, mining and smelting, and battery repair and recycling (5).

Lead hazard has recently shifted from an occupational nature to an
environmental one. For example, a study to determine the effect of
atmospheric pollution by lead on the blood lead concentration in
children was made on elementary school children who lived near a
smelter and a mast lamp factory. Another group of children from a
school in a residential area without apparent atmospheric pollution
served as a control. The differences in the medians of blood lead
concentration of children between exposed and control groups were
highly significant (P value less than 0.01) (6).

References
----------
1. World Health Organization (WHO) 2009. Water-related Diseases.
(available at <http://www.who.int/water_sanitation_health/diseases/lead/en/>).
2. Agency for Toxic Substances and Disease Registry (ATSDR). 2007.
ToxFAQs for lead (available at <http://www.atsdr.cdc.gov/tfacts13.html>).
3. Ye X, Wong O: Lead exposure, lead poisoning, and lead regulatory
standards in China, 1990-2005. Regul Toxicol Pharmacol, Nov 2006;
46(2): 157-62 (abstract available at
<http://www.ncbi.nlm.nih.gov/pubmed/16782249>).
4. Shen X, Rosen JF, Guo D, Wu S: Childhood lead poisoning in China.
Sci Total Environ, Mar 1996; 181(2): 101-9 (abstract available at
<http://www.ncbi.nlm.nih.gov/pubmed/8820381>).
5. Falk H: International Environmental Health for the Pediatrician:
Case Study of Lead Poisoning. Pediatrics, Jul 2003; 112: 259-64 (full
article available at
<http://pediatrics.aappublications.org/cgi/reprint/112/1/S1/259>).
6. Wang YL: Industrial lead poisoning in China over the past 33
years. Ecotoxicol Environ Saf, Dec 1984; 8(6): 526-30 (abstract
available at <http://www.ncbi.nlm.nih.gov/pubmed/6391901>).

For a map of China with provinces, see
<http://www.lib.utexas.edu/maps/middle_east_and_asia/china_pol01.jpg>.
For the interactive HealthMap/ProMED-mail map of China with links to
other ProMED-mail and PRO/MBDS postings in China and surrounding
areas, see <http://healthmap.org/r/00G5>. - Mod.SCM]

See Also