Potential dietary factors for reducing lead burden of Chinese preschool children.

Dietary approaches to treat children's low lead exposure are implemented routinely in China, while evidence for the effect could not be provided until now. The aim of this study was to examine the relationship between diets including nutrition supplementation and blood lead level of preschool children of China. In total, 17,859 preschool children from 14 cities were recruited, and their social-demography, living environment, and dietary intakes were collected, and capillary blood sample was tested for lead concentration. The average blood lead concentration was 34.5 µg/L, and after adjusting children's social-demography factors, the consumption of milk or dairy production, fruits, and calcium supplementation had negative dose-response relationships with blood lead level. Conversely, intake of iron-rich food and supplementation was not associated. Further studies are needed to prove the causal relationships.

A dietary and nutritional status survey among young children in five big cities of China.

BACKGROUND AND OBJECTIVES: To investigate the dietary patterns and nutritional status of young children living in urban environments in China. METHODS AND STUDY DESIGN: A cross-sectional study was conducted of 750 children aged 6 - 35 months living in 5 large cities in China. The survey methodology included a physical exami-nation, blood hemoglobin measurements and a 24 hour dietary recall questionnaire Results: The educational lev-el of participant mothers was high (79% had attended college or university or higher), which may not be fully representative across all areas of urban China. Overall anthropometric nutritional status indicators were within acceptable ranges based on national recommendations, and there was no evidence of severe micronutrient defi-ciencies. However, we identified three significant nutritional issues that warrant attention: 1.) Later than optimal introduction and low-intake of animal-based iron-containing foods into the diet, and a need for greater inclusion of vitamin B-1 rich foods among 12-35 month old children. 2.) Presence of significant rates of anemia in 6-11 and 12-23 month old children. 3.) An increased risk of overweight/obesity. CONCLUSIONS: Since food availability and affordability are no longer major issues in the well developed parts of urban China, achieving further im-provements in the diet and nutrition of young children in these environments is likely require more specific edu-cation to parents and other significant carers such as grandparents. The relatively high educational level and so-cio-economic status of the population group is likely to facilitate the uptake of such measures in this population group.

Trend of childhood blood lead levels in cities of China in recent 10 years.

The adverse effects of lead on human especially childhood have been well established. Largely due to the phase out of lead in gasoline, blood lead levels (BLLs) had declined substantially all over the world including China. In 2004, 2007, 2010, and 2013, we conducted a continuous project including 47,346 children aged 0-6 years old from 11 cities all over China to show how the decline happened and to explore what to do next to improve the BLLs of children of China. Our data shown the BLLs of Chinese children decreased from 46.38, 43.58, 38.95 to 37.17 µg/L, but the decline was not enough. These decline was mainly because of the number decrease of children with high BLLs. Integrated strategy should be used to promote the BLLs of Chinese children, like striving to improve the environment, setting new cutoff for high BLLs, and establishing routine blood lead screening.

Evaluation of the Relationship Between Height and Zinc, Copper, Iron, Calcium, and Magnesium Levels in Healthy Young Children in Beijing, China.

We evaluated the relationship between child (aged 6-36 months) height and blood zinc, copper, iron, calcium, and magnesium concentrations. We selected 840 children following a physical examination. Weight and supine length or standing height were measured according to the World Health Organization guidelines. Polarographic analysis was used to measure zinc, copper, iron, magnesium, and calcium levels. Differences in heights between groups with low vs. high mineral concentrations, stratified by sex and age, were compared by analysis of variance. Relationships between these five elements and heights were tested by multiple regression analysis. Zinc levels in the shorter group (height for age (HAZ) ≤ -0.3) were 135.84 ± 39.76 and 134.83 ± 37.57 µmol/L in boys and girls, respectively. Zinc concentrations in the taller group (HAZ > -0.3) were 142.50 ± 35.85 and 140.52 ± 35.80 µmol/L in boys and girls, respectively. The difference between the two height groups in boys and girls was statistically significant. Compared with those (143.06 ± 33.76 µmol/L) in the taller group, zinc concentration (131.30 ± 40.75 µmol/L) in the shorter group was significantly lower (p = 0.04) at age 6-12 months. Height was positively correlated with zinc level in children aged 6-12 months (p < 0.05). Zinc levels were positively correlated with calcium, magnesium, and iron concentrations in children aged 6-36 months (p < 0.05). Our results indicated that zinc levels and height are correlated, and zinc levels were related to calcium, magnesium, copper, and iron concentrations. Therefore, to ensure healthy development in children, blood levels of these five elements should be balanced.

Dietary survey of anaemic infants and young children in urban areas of China: a cross-sectional study.

BACKGROUND AND OBJECTIVES: To explore the diet characteristics of anaemic infants and young children of China, blood tests and diets surveys were conducted in five cities. METHODS AND STUDY DESIGN: About 150 children aged 6-36 mo were selected in a typical community health center of each city, and the total sample was 750. Nutritional status was measured through 24h dietary recall method and HEMO Cue was used for Haemoglobin concentration testing. RESULTS: The average prevalence of anaemia was 17.2% in 6-12 mo children, which was higher than in other age groups. Median intakes of 8 nutrients (protein, vitamin A, B-1 and C, calcium, iron, zinc and copper) in anaemic children were less than non-anaemic children (p<0.05) in 6-12 mo olds; at age 12-24 mo the intake of vitamin A in anaemic children was less than in non-anaemic children (p<0.05). Market complementary food was the main source of iron in both anaemic and non-anaemic children (6-12 mo olds: 2.28 and 3.69 mg; 12-24 mo olds: 2.06 and 2.09 mg, respectively). Iron intake from formula was lower in anaemic children than in nonanaemic children (6-12 mo olds: 0.88 vs 2.54 mg; 12-24 mo olds: 1.59 vs 2.87 mg). The proportion of children obtaining continued breastfeeding in anaemic children was significantly higher than in non-anaemic children aged 6-12 mo (65% vs 37%, p<0.05). CONCLUSIONS: Appropriate practices around continuing breastfeeding and complementary feeding particularly targeted to breast fed older infants and young children are needed to reduce anaemia in infants and young children.

Surveillance of childhood blood lead levels in 11 cities of China.

BACKGROUND: Exposure to lead can be deleterious to children's health. Surveillance for blood lead levels (BLLs) is reported every year in the USA and some other countries. However, such reports are lacking in China which has the world's largest population of children. In this study, we provided the latest nationally representative data on BLLs among Chinese children living in cities, described the change in BLLs since 2004, and explored the risk factors for elevated BLLs (EBLLs) among children. METHODS: We studied 12 693 children aged 0-6 years in 2004 and 11 255 children aged 0-6 years in 2010. We evaluated the average BLLs and the prevalence of EBLLs, and a multivariate logistic regression model was used to estimate predictors of EBLLs. RESULTS: The geometric mean BLLs of children aged 0-6 years dropped by 16% (from 46.38 ± 2.10 µg/L in 2004 to 38.95 ± 1.83 µg/L in 2010), while the prevalence of EBLLs dropped by 87% (from 9.78% in 2004 to 1.32% in 2010). In a multivariate analysis, the following factors were associated with EBLLs: (1) children being cared for at home or at a boarding nursery (compared to children being cared for in a day nursery), (2) children having fathers with a lower education level, and (3) children often eating popcorn and chewing fingernails or sucking fingers were associated with EBLLs. CONCLUSIONS: The results of this study demonstrated a substantial decline in BLLs from 2004 to 2010 among Chinese children 0-6 years living in cities. However, these levels were higher than levels in countries, such as the USA, Canada, Japan and Sweden. These data demonstrate that Chinese children's lead exposure remains a public health problem that requires additional effort and resources.

Blood lead levels among children aged 0 to 6 years in 16 cities of China, 2004-2008.

BACKGROUND: The adverse health effects of lead for children under 6 years are well known. Studies to assess the lead exposure among children in China are small in sample size and lack of national representative data. The aim of this study therefore was to describe blood lead levels and identify risk factors for lead exposure among children aged 0 to 6 years living in 16 cities in China. METHODS: We analyzed data from blood lead levels surveillance in China carried out in 16 large cities between 2004 and 2008. A stratified clustered random sampling strategy was used. A total of 69 968 children aged 0 to 6 years were included. We conducted multiple Logistic regression analyses to explore risk factors to high blood lead level. RESULTS: The geometric mean blood lead level of the children was 4.50 µg/dl (median: 4.90 µg/dl; IQR: 3.20 - 7.00 µg/dl). Overall prevalence of blood lead level ≥ 10.00 µg/dl among 0- to 6-year-old children was 7.57%. But the proportion of blood lead level ≥ 5.00 but < 10.00 µg/dl was 42.12%. Blood lead levels were significantly higher in boys (4.63 µg/dl) than in girls (4.35 µg/dl) (P < 0.0001). The geometric mean blood lead levels and prevalence of blood lead level ≥ 10.00 µg/dl increased with age (P < 0.0001 for the two trends). After controlling for sociodemographic, dietary and behavior factors, multivariable analysis indicated that lower maternal education, male gender, younger age, often biting pencil or/and toys, walking or playing for long time on the street, not washing hands before eating are major risk factors for higher lead levels. CONCLUSIONS: The blood lead levels among Chinese children in urban areas are lower than previous studies but close to those of developed countries. However, children with low lead exposure account for almost half and the sociodemographic factors (age, male sex, and low mother education level) continue to be associated with higher blood lead levels.

A comparison between antenatal care quality in public and private sector in rural Hebei, China.

AIM: To evaluate the quality of antenatal care (ANC) in Hebei Province and compare it between the public and private sector and within the public sector. METHODS: We conducted a Maternal, Newborn and Child Health Household Survey in 2010 using a two-stage sampling procedure and included 1079 mothers. The quality of ANC was assessed on the basis of the number of ANC visits, the time of the first ANC visit, 16 different ANC procedures, owning a maternal health care booklet, and the type of service provider. RESULTS: Almost all women (98%) received ANC services at least once, 80% at least four times, and 54% at least five times. About half of the women (46%) visited ANC facility within their first trimester. Neither public nor private sector provided all 16 standardized services, but significantly more women in public sector received ANC procedures. Most women received ANC in county or higher-level hospitals (75%) and very few in township hospitals (8%). Significantly fewer women were weighed and tested for HIV/AIDS in township than in county or higher-level hospitals. CONCLUSION: The quality of ANC in Hebei was poorer than required by China's national and World Health Organization norms. Although the public sector performed better than the private sector, the utilization and quality of care of ANC services in this sector varied and women generally visited county or higher-level health facilities.

[Blood lead status and influencing factors among preschool children in urban areas of China].

OBJECTIVE: To investigate the blood lead status and influencing factors among preschool children in the sampling city. METHOD: Stratified-clustered-random sampling was used. Standardized questionnaire and peripheral blood samples were obtained from 69 968 children aged 0-6 years in fixed kindergartens and communities of Yinchuan, Xi'an, Chengdu, Wuhan, Hefei, Beijing, Harbin, Zhengzhou, Huhhot, Shijiazhuang, Haikou, Dalian, Qingdao, Guangzhou, Nanning and Changsha from 2004 to 2008, respectively. Tungsten atomic absorbtion spectrophotometry was employed to determine the blood lead level of children. RESULT: The proportion of children with blood lead level ≥ 100 µg/L was 7.57% (among which the proportion of high blood lead level, mild lead poisoning, moderate lead poisoning, severe lead poisoning were 91.0%, 2.76%, 3.32%, 2.93%, respectively) and the blood lead level was lower than those of the past studies. The proportion of high blood lead level has steadily declined from 2004 to 2008 [the proportions were 10.03%, 7.85%, 7.40%, 6.91% and 4.78%, respectively (χ(2) = 297.36, P < 0.0001)]. The proportion of children with blood lead level ≥ 100 µg/L in Haikou, Zhengzhou, Guangzhou, Shijiazhuang, Changsha, Xi'an, Wuhan, Hefei, Chengdu, Yinchuan, Harbin, Beijing, Dalian, Huhhot, Nanning and Qingdao were 12.15%, 10.49%, 10.37%, 9.69%, 9.53%, 9.46%, 9.40%, 8.50%, 7.99%, 7.98%, 7.51%, 6.10%, 3.25%, 2.89%, 2.46% and 2.39%, respectively (χ(2) = 768.21, P < 0.0001). By multiple regression method, the risk factors which influenced blood lead status of children were education status of mother, older children, behavior and dietary habit of children, boy, stay for long time in traffic busy areas, the type of housing, taking traditional Chinese and herbal medicine. The protective factors against lead poisoning in children mainly included scattered living, the nutritional status of calcium, iron, zinc, frequent intake of milk, and older mother. CONCLUSION: The blood lead level of children has decreased, but is still higher than those in developed countries. Lead exposure remains a public health issue which affects children most. The blood lead level of children is affected by multiple factors. Government and the whole society should pay attention to interrupt the lead pollutant and to promote nutritional health education. With all these efforts, it is possible to stop the progress of lead exposure and reduce its hazardous effects on the growth and development of children.

Surveillance of childhood blood lead levels in 14 cities of China in 2004-2006.

OBJECTIVE: To investigate the blood lead level in children aged 0-6 years in urban areas of China. METHODS: Fourteen cities were selected as sites under surveillance. A total of 44 045 peripheral blood specimens were collected from 2004 to 2006, during which 15 727, 14 737, and 13 584 specimens were tested in 2004, 2005, and 2006, respectively. Tungsten atomizer absorption spectrophotometer was employed to determine blood lead level. RESULTS: The geometric mean blood lead level in the tested children was 47.10 microg/L with 10.10% > or = 100 microg/L, 46.17 microg/L with 7.78% > or = 100 microg/L, and 47.03 microg/L with 7.30% > or = 100 microg/L in 2004, 2005, and 2006, respectively. The blood lead levels seemed to tend to rise in parallel with the increase of age of the children and were higher in boys (48.84 microg/L, 47.56 microg/L, and 47.78 microg/L in the 3 respective years) than in girls (45.00 microg/L, 44.53 microg/L, and 46.13 microg/L). CONCLUSION: The blood lead levels in children in cities of China are lower than those in previous national studies, but higher than those in developed countries. Childhood lead poisoning remains a public health problem in China.

[Study on blood lead level and related risk factors among children aged 0-6 years in 15 cities in China].

OBJECTIVE: To observe blood lead level and related risk factors among children aged 0-6 years old living in cities in China and to provide data for policy development to the prevention on environmental lead pollution. METHODS: A stratified-clustered-random sampling method was used. 17 141 peripheral blood samples of 0-6 years old children from 15 cities in China were tested. Tungsten atomizer absorption spectrophotometer was employed to determined the blood lead level. Related factors were also studied using a standardized questionnaire. Data were analyzed on related risk factors that affecting blood lead levels through multiple regression method. RESULTS: The mean blood lead level of 0-6 years old children from 15 cities in China was 59.52 microg/L including 10.45% of those > or =100 microg/L, and 0.62% > or = 200 microg/L. However, the blood lead levels seemed to have had a trend of increase parallel to age among 0-6 years-old children and were higher for boys (59.50 microg/L) than girls (54.95 microg/L). The risk factors which influenceing children's blood lead levels would include the type of housing, parent's education levels, social status and hobby, children's behavior habit, dieting habit and nutritional condition. CONCLUSION: The blood lead levels of children in China were lower than data gathered from former national studies but higher than those from developed countries, suggesting that the. Government and the whole society should be aware of the problem on lead poisoning among children during their childhood.

[Prevalence of vitamin A deficiency in children under six years of age in Tibet, China].

OBJECTIVE: To understand the prevalence of vitamin A deficiency (VAD) among children under six years of age in Tibet, China. METHODS: Totally, 1 257 children under six years of age were selected from two cities, two farming counties, two semi-farming counties and two livestock farming counties with stratified cluster sampling to asses VAD status in Tibet. Family information, children's feeding and disease history in the previous two weeks were collected by questionnaire. Blood specimen was collected from each child and serum was separated for detection of vitamin A concentration with microfluorescent spectrophotometry. RESULTS: Totally, 1 257 children under six years of age were surveyed, with 635 boys, 622 girls, 862 aged over two years, and 98.5% of Tibet nationality. Six cases of night blindness and two cases of xerophthalmia were detected from them, with prevalence of clinical VAD of 0.96%. Eighteen of 1071 mothers with children under six years of age were found suffering from night blindness, accounting for 1.7%. Clinical cases of VAD both in children and mothers came from all four sampling strata. Average serum concentration of vitamin A and prevalence of subclinical VAD (serum vitamin A lower than or equal to 0.70 micromol/L) was 1.15 micromol/L and 5.4% and 1.12 micromol/L and 4.7% in cities and livestock farming counties, respectively, significantly higher than those in farming (1.04 micromol/L and 11.0%) and semi-farming counties (1.05 micromol/L and 12.3%), respectively, as compared to average levels of 1.09 micromol/L and 8.4% in the autonomous region as a whole. Prevalence of subclinical VAD in children under six months and those aged six to eleven months were 22.2% and 13.3%, respectively, significantly higher than those in children aged one year (8.5%), two to three years (5.4%) and four to five years (7.9%), respectively. There was also significant difference in serum level of vitamin A between children at varied ages, but no significant difference both in serum level of vitamin A and prevalence of subclinical VAD between gender was found. CONCLUSIONS: In general, status of VAD in children of Tibet was milder than that at national level. But, moderate subclinical VAD in some areas, such as farming and semi-farming counties, did exist, so vitamin A supplementation aiming to children, especially those under one year of age, in those areas should be urged.

Prevalence of subclinical vitamin A deficiency and its affecting factors in 8 669 children of China.

OBJECTIVE: The survey will reveal current status of subclinical vitamin A deficiency (SVAD) and explore its affecting factors in children of China. METHODS: Totally 8 669 children aged under 6 years were randomly selected from 14 provinces for clinical examination, health and dietary questionnaire and serum level of vitamin A measurement with fluorescence method. The cut-off value for SVAD was defined as

[Survey on vitamin A deficiency in children under-6-years in China].

OBJECTIVE: To understand the prevalence and spatial distribution of vitamin A deficiency (VAD) in China among children at ages under six years. METHODS: About 8,600 children under 6 years of age in 14 cities and 28 counties of 14 provinces were selected with stratified cluster sampling for survey, including interview with questionnaire for their family information and nutritional status. Blood specimens were collected for measuring serum level of VA with fluorescent spectrophotometry in laboratory. RESULTS: Totally, 8,669 children under 6 (2,877 in urban area and 5,792 in rural area) were surveyed in 14 provinces, with 4,629 males and 4,040 females. Eight cases of night blindness and seven cases of xerophthalmia were found among the children at ages of two to five years. Sixty-one mothers of the children in this group were also found suffering from night blindness. All the cases of night blindness and xerophthalmia both in children and mothers were living in rural areas. Based on their serum levels of VA, 11.7% of the all 1 018 children were diagnosed as VAD, with serum VA concentrations below or equal to 0.70 micro mol/L. Prevalence of VAD was 15.0% and 5.8% in rural (23.3% in the poverty-stricken counties) and urban areas, respectively, and 5.8%, 11.5% and 16.8% in the coastal, inland and remote areas, respectively. The average serum level of VA was 1.20 micro mol/L and 0.99 micro mol/L for urban and rural areas, respectively, with a national average of 1.06 micro mol/L. And, babies under six months of age with an average serum levels of VA < or = 0.70 micro mol/L accounted for 33.4%, and those at ages of four to five years with the same level of VA accounted for 8%. There was significant difference in serum levels of VA between ages, but no significant difference between genders. CONCLUSION: VAD did exist in children of China, especially in the remote and poverty-stricken rural areas and VA supplementation is urgently needed for the children in these regions.