Nutrition-pollution interaction: An emerging research area

The impact of environmental pollution, especially chronic low exposures of heavy metals (Pb, Cd, Hg, As, Cr, etc.) on nutritional status and health of human and livestock, has become a cause of concern. It is established that malnutrition inhibits enzyme system, alters neurotransmitter levels, degenerate myelin, glial and neural elements, lowering of IQ scores as well as impairment of fine and gross motor coordination. Chronic low-level exposure to heavy metals also results in similar type of deformities at sub-clinical level. However, additive impact of undernutrition and adverse effects of heavy metal exposure is emerging as a serious threat to health in developing countries. High blood Pb/Cd levels and low nutrient levels cause subclinical damage of organ system such as haemopoietic, renal, nervous systems in neonates, children, post-partum women, and occupationally exposed population. This could be due to chronic low-level heavy metal exposures and vis-à-vis interaction between pollutants and nutrients. Our studies are focused on the utility of biomarkers for early subclinical detection of haemopoietic and rental toxicity. Lead exposure from non-conventional sources such as toys, pet/glass bottles, etc. suggest long-term investigation. The present review compiles result of studies conducted in this area highlighting the importance of pollution-nutrition interaction. This may facilitate policymakers on developing the strategies to counter the heavy metal exposure of humans/livestock and their consequences.

The maturation state of the auditory nerve and brainstem in rats exposed to lead acetate and supplemented with ferrous sulfate / Estado de maturação do nervo auditivo e tronco encefálico em ratos expostos a acetato de chumbo e suplementados com sulfato ferroso

Abstract Introduction The literature has reported the association between lead and auditory effects, based on clinical and experimental studies. However, there is no consensus regarding the effects of lead in the auditory system, or its correlation with the concentration of the metal in the blood. Objective To investigate the maturation state of the auditory system, specifically the auditory nerve and brainstem, in rats exposed to lead acetate and supplemented with ferrous sulfate. Methods 30 weanling male rats (Rattus norvegicus, Wistar) were distributed into six groups of five animals each and exposed to one of two concentrations of lead acetate (100 or 400 mg/L) and supplemented with ferrous sulfate (20 mg/kg). The maturation state of the auditory nerve and brainstem was analyzed using Brainstem Auditory Evoked Potential before and after lead exposure. The concentration of lead in blood and brainstem was analyzed using Inductively Coupled Plasma-Mass Spectrometry. Results We verified that the concentration of Pb in blood and in brainstem presented a high correlation (r = 0.951; p < 0.0001). Both concentrations of lead acetate affected the maturation state of the auditory system, being the maturation slower in the regions corresponding to portion of the auditory nerve (wave I) and cochlear nuclei (wave II). The ferrous sulfate supplementation reduced significantly the concentration of lead in blood and brainstem for the group exposed to the lowest concentration of lead (100 mg/L), but not for the group exposed to the higher concentration (400 mg/L). Conclusion This study indicate that the lead acetate can have deleterious effects on the maturation of the auditory nerve and brainstem (cochlear nucleus region), as detected by the Brainstem Auditory Evoked Potentials, and the ferrous sulphate can partially amend this effect.

Resumo Introdução A literatura relatou a associação entre o chumbo e os efeitos auditivos, com base em estudos clínicos e experimentais. No entanto, não há consenso em relação aos efeitos do chumbo no sistema auditivo, ou sua correlação com a concentração do metal no sangue. Objetivo Investigar o estado de maturação do sistema auditivo, especificamente do nervo auditivo e do tronco encefálico, em ratos expostos ao acetato de chumbo e suplementados com sulfato ferroso. Método 30 ratos machos desmamados (Rattus norvegicus, Wistar) foram distribuídos em seis grupos de cinco animais e expostos a uma de duas concentrações de acetato de chumbo (100 ou 400 mg/L) e suplementados com sulfato ferroso (20 mg/kg). O estado de maturação do nervo auditivo e do tronco encefálico foi analisado pelo Potencial Evocado Auditivo do Tronco Encefálico antes e após a exposição ao chumbo. A concentração de chumbo no sangue e tronco encefálico foi analisada utilizando-se Espectrometria de Massa com Plasma Indutivamente Acoplado. Resultados Verificamos que as concentrações de Pb no sangue e no tronco encefálico apresentaram alta correlação (r = 0,951, p < 0,0001). Ambas as concentrações de acetato de chumbo afetaram o estado de maturação do sistema auditivo, a maturação foi mais lenta nas regiões correspondentes à porção do nervo auditivo (onda I) e dos núcleos cocleares (onda II). A suplementação com sulfato ferroso reduziu significativamente a concentração de chumbo no sangue e no tronco encefálico no grupo exposto à menor concentração de chumbo (100 mg/L), mas não para o grupo exposto à maior concentração (400 mg/L). Conclusão Esse estudo indica que o acetato de chumbo pode ter efeitos deletérios na maturação do nervo auditivo e do tronco encefálico (região do núcleo coclear), como detectado pelos potenciais evocados auditivos do tronco encefálico, e que o sulfato ferroso pode diminuir parcialmente esse efeito.

Association of Bone Turnover Levels with MTHFR Gene Polymorphisms among Pregnant Women in Wuhan, China / 华中科技大学学报（医学）（英德文版）

Pregnancy is a critical stimulator of bone mineral resorption.We used to find the MTHFR gene polymorphisms are related with blood lead levels among pregnant women.Pregnancy-stimulated bone turnover may be associated with MTHFR gene polymorphisms too.In this article,we aimed to determine the relationship between MTHFR gene polymorphisms and bone turnover rates among the pregnant women.The participants including pregnant and non-pregnant women were selected and recruited during their routine prenatal or physical examination from July to October in 2012.A total of 1000 participants,including 250 pregnant women in the first,second,and third trimesters and 250 non-pregnant women,were enrolled in the study.Finally,after excluding 27 participants unable to provide blood samples,973 eligible participants (i.e.,234,249,and 248 pregnant women in the first,second,and third trimesters,respectively,and 242 non-pregnant women)were included in the research.The MTHFR gene 1298CC homozygote carriers were more susceptible to yield higher plasma homocysteine levels than the 1298AA/AC carriers,with standardized coefficients of 0.086 (P＜0.05) and 0.104 (P＜0.01) of all the participants and the pregnant women,respectively.The MTHFR gene 1793AA homozygote carriers more likely showed higher plasma osteocalcin levels (standardized β=0.091,P＜0.01) than the 1793GG/GA carriers among all the subjects.Plasma homocysteine levels were positively correlated with blood lead levels among the participants and the pregnant women with standardized coefficients of 0.320 (P＜0.01) and 0.179 (P＜0.01),respectively.Plasma osteocalcin levels were positively associated with blood lead levels among pregnant and non-pregnant women with standardized coefficients of 0.084 (P＜0.05) and 0.125 (P＜0.01),respectively.In conclusion,homocysteine and osteocalcin contents in plasma are associated with the MTHFR gene A1298C polymorphism and blood lead levels among pregnant women.The MTHFR gene A 1298C polymorphism-related homocysteine is a possible risk factor for increased blood lead levels among Chinese women.

Association of Bone Turnover Levels with MTHFR Gene Polymorphisms among Pregnant Women in Wuhan, China / 华中科技大学学报（医学）（英德文版）

Pregnancy is a critical stimulator of bone mineral resorption.We used to find the MTHFR gene polymorphisms are related with blood lead levels among pregnant women.Pregnancy-stimulated bone turnover may be associated with MTHFR gene polymorphisms too.In this article,we aimed to determine the relationship between MTHFR gene polymorphisms and bone turnover rates among the pregnant women.The participants including pregnant and non-pregnant women were selected and recruited during their routine prenatal or physical examination from July to October in 2012.A total of 1000 participants,including 250 pregnant women in the first,second,and third trimesters and 250 non-pregnant women,were enrolled in the study.Finally,after excluding 27 participants unable to provide blood samples,973 eligible participants (i.e.,234,249,and 248 pregnant women in the first,second,and third trimesters,respectively,and 242 non-pregnant women)were included in the research.The MTHFR gene 1298CC homozygote carriers were more susceptible to yield higher plasma homocysteine levels than the 1298AA/AC carriers,with standardized coefficients of 0.086 (P＜0.05) and 0.104 (P＜0.01) of all the participants and the pregnant women,respectively.The MTHFR gene 1793AA homozygote carriers more likely showed higher plasma osteocalcin levels (standardized β=0.091,P＜0.01) than the 1793GG/GA carriers among all the subjects.Plasma homocysteine levels were positively correlated with blood lead levels among the participants and the pregnant women with standardized coefficients of 0.320 (P＜0.01) and 0.179 (P＜0.01),respectively.Plasma osteocalcin levels were positively associated with blood lead levels among pregnant and non-pregnant women with standardized coefficients of 0.084 (P＜0.05) and 0.125 (P＜0.01),respectively.In conclusion,homocysteine and osteocalcin contents in plasma are associated with the MTHFR gene A1298C polymorphism and blood lead levels among pregnant women.The MTHFR gene A 1298C polymorphism-related homocysteine is a possible risk factor for increased blood lead levels among Chinese women.

Blood lead levels in a group of children: the potential risk factors and health problems / Níveis de chumbo no sangue em um grupo de crianças: possíveis fatores de risco e problemas de saúde

Abstract Objective: To investigate blood lead levels in schoolchildren in two areas of Egypt to understand the current lead pollution exposure and its risk factors, aiming to improve prevention politicies. Subjects and method: This was a cross-sectional study in children (n = 400) aged 6-12 years recruited from two areas in Egypt (industrial and urban). Blood lead levels were measured using an atomic absorption method. Detailed questionnaires on sources of lead exposure and history of school performance and any behavioral changes were obtained. Results: The mean blood lead level in the urban area of Egypt (Dokki) was 5.45 ± 3.90 µg/dL, while that in the industrial area (Helwan) was 10.37 ± 7.94 µg/dL, with a statistically significant difference between both areas (p < 0.05). In Dokki, 20% of the studied group had blood lead levels ≥ 10 µg/dL, versus 42% of those in Helwan. A significant association was found between children with abnormal behavior and those with pallor with blood lead level ≥ 10 µg/dL, when compared with those with blood lead level < 10 µg/dL (p < 0.05). Those living in Helwan area, those with bad health habits, and those living in housing with increased exposure were at a statistically significantly higher risk of having blood lead level ≥ 10 µg/dL. Conclusion: Lead remains a public health problem in Egypt. High blood lead levels were significantly associated with bad health habits and housing with increased exposure, as well as abnormal behavior and pallor.

Resumo Objetivo: Investigar os níveis de chumbo no sangue (NCSs) em crianças em idade escolar em duas áreas do Egito para entender a atual exposição à poluição por chumbo e seus fatores de risco, para melhorar as políticas de prevenção. Indivíduos e método: Este foi um estudo transversal em crianças (400) entre 6-12 anos recrutadas de duas áreas no Egito (industrial e urbana). Os NCSs foram medidos por um método de absorção atômica. Foram obtidos questionários detalhados sobre as fontes de exposição ao chumbo e o histórico de desempenho escolar e quaisquer alterações comportamentais. Resultados: O NCS na área urbana do Egito (Dokki) foi de 5,45 ± 3,90 µg/dL, ao passo que na área industrial (Helwan) foi de 10,37 ± 7,94 µg/dL, com uma diferença significativa entre ambas as áreas (p < 0,05). Na área de Dokki, 20% do grupo estudado apresentaram NCSs ≥10 µg/dL, ao passo que na área de Helwan foi 42%. Foi encontrada uma associação significativa entre as crianças com comportamento anormal e aquelas com palidez com NCS ≥ 10 µg/dL, em comparação com aquelas com NCS < 10 µg/dL (p < 0,05). Aquelas que moram na área de Helwan, aquelas com hábitos de saúde ruins e aquelas que moram em moradias com maior exposição estiveram significativamente em alto risco de apresentar NCS ≥ 10 µg/dL. Conclusão: O chumbo ainda é um problema de saúde pública no Egito. Altos NCSs foram significativamente associados a hábitos de saúde ruins e moradia com maior exposição, bem como comportamento anormal e palidez.

Concentraciones de plomo en sangre y reprobación de escolares en la ciudad de México / Blood lead levels and poor school performance among children in Mexico City

Objetivo: Describir la relación de los niveles de plomo en sangre y reprobación escolar. Material y métodos: Estudio transversal en 792 escolares de 7 a 14 años de edad asistentes a la consulta externa de cinco hospitales pediátricos de la ciudad de México en 1996. Se midió el nivel de plomo en sangre, se exploró la exposición al metal, así como el desempeño académico. Resultados: Se reportó una media de plomo en sangre de 8.6 μg/dL y una media geométrica de 7.7 μg/dL. La principal fuente de exposición fue el uso de loza de barro vidriado (diferencia de uso = –1.182, p = 0.000). En los escolares que reprobaron algún año, la media geométrica de plomo en sangre fue de 8.1 μg/dL, en comparación con los niños que no reprobaron (media geométrica = 7.6 μg/dL, p = 0.240). El riesgo de reprobar entre el primer y el tercer año de primaria con plomo en sangre mayor a 10 μg/dL fue de 1.73 (p=0.012, IC 95% 1.13-2.66), y del primero al cuarto año de primaria fue de 1.62 (p=0.021, IC 95% 1.07-2.46). Conclusiones: Es probable que el plomo sanguíneo, entre otros condicionantes, contribuya a la reprobación repetida en los escolares de este estudio.

OBJECTIVE: To describe the relationship between blood lead levels (BLL) and poor school performance. MATERIAL AND METHODS: A cross-sectional study was carried out in 1996 among 792 schoolchildren aged 7-14 years, who attended the outpatient units of five pediatric hospitals of Mexico City. BLL was measured together with lead exposure and academic performance. RESULTS: Reported BLL and geometric means (GM) were 8.6 microg/dL and 7.7 microg/dL, respectively. The main source of exposure was the use of glazed pottery (difference of use =-1.182; p = 0.000). Among schoolchildren who failed any school year, GM of the BLL was 8.1 microg/dL, compared with children who did not fail (GM = 7.6 microg/dL; p = 0.240). The risk of failing a school year between the 1st and 3rd grade with a BLL greater than 10 microg/dL was 1.73 (p = 0.012, IC 95% 1.13-2.66) and from 1st to 4th grade was 1.62 (p = 0.021, IC 95% 1.07-2.46). CONCLUSIONS: Blood lead levels, among other conditions, may contribute to the failure in school performance observed in the children participating in this study.

Blood Lead Levels of Children in Rural Areas of China / 环境与健康杂志

Objective To evaluate Chinese rural children's blood lead levels (BLLs) and identify its distribution features and to provide data for policy development to the prevention of rural environmental lead pollution. Methods The papers on rural children's BLLs published from 1994 to Oct, 2008 were collected by using CNKI's (China National Knowledge Infrastructure) Chinese Journal Full-test Database and other ways. The papers which were eligible for the following criteria were reviewed:(1) BLLs measured by atomic absorption spectroscopy (graphite or others) or inductively coupled plasma-mass spectrometry; (2) strict quality control; (3) no local lead pollution sources in the areas where the screened subjects live in; (4) children aged from 0 to 14 years old; (5)sample size more than 40. Results Analysis on the included 32 papers indicated that, the mean BLLs of Chinese rural children between 1994 and 2008 was 74.93 ?g/L ( range:41.14-193.54 ?g/L)and 19.32%( range:2.2%-43%) of the subjects had BLLs higher than 100 ?g/L. The rural children’s BLLs changed from 87.53 ?g/L to 71.16 ?g/L after the use of lead free gasoline in 2000 in China, which were both lower than the general children's BBLs before 2000 and after 2001. The children in Beijing city and Shandong province showed the highest mean BLLs , with 99.16 ?g/L and 92.13 ?g/L respectively; while the children in Jilin province and Hebei province showed the lowest levels, with 41.14 ?g/L and 56.14 ?g/L respectively. The comprehensive analysis of 18 papers indicated that the mean BLLs in rural areas and urban areas were 77.90 ?g/L and 87.24 ?g/L respectively ( u=3.73, P

Children Blood Lead Levels and Influencing Factors after Unleaded Gasoline Used in Guangzhou / 环境与健康杂志

100 ?g/L), 36(2.90%)male and twenty four (2.09%)female. BLLs(G) in Baiyuen (suburb) children(60.33 ?g/L) was the highest among three districts, Yuxiu (downtown) was 58.09 ?g/L and Zengcheng (countryside)was 56.72 ?g/L. Linear regressions (stepwise) were taken with geometric BLLs as dependent, 34 items as independents in SPSS 11.5. Fathers with lower diploma, narrower houses, better aired houses, fewer hand washings and sucking fingers were the risk factors for children high BLLs. Conclusion BLLs in suburb children become the highest after unleaded gasoline used in Guangzhou. The housing circumstance and hygienic behavior of children may effect the blood lead level.

Blood Lead Levels in Children / 대한산업의학회지

The authors conducted this study to evaluate some differences in blood lead levels between inner-city and suburban children and obtain the basic data of the reference value of the blood lead concentrations in children. The subjects were composed of 102 children residing in inner-city and 86 children in suburban. Their age range were 6 to 8 years old and the obtained results were as follow; 1. The arithmetic means of the blood lead level in male and fenlale, male, and female children were 7.24, 7,40, 7.08 microgram/100ml, and geometric means were 6.92, 7.08, 6.76 microgram/100ml, respectively. 2. The children residing in inner-city had the higher blood lead levels both male and female than suburban children with statistical signficance (p or = 10 microgram/100ml group, the inner-city children (20.39 %) were more distributed than suburban chilren(2.33 %) , and 12.33 % of total subjects had this lead values.