Skip to main content
NCBI home page
Environmental Health Perspectives logoLink to Environmental Health Perspectives
. 2001 Oct;109(10):1079–1084. doi: 10.1289/ehp.011091079

Iron deficiency associated with higher blood lead in children living in contaminated environments.

A Bradman 1, B Eskenazi 1, P Sutton 1, M Athanasoulis 1, L R Goldman 1
PMCID: PMC1242086  PMID: 11675273

Abstract

The evidence that iron deficiency increases lead child exposure is based primarily on animal data and limited human studies, and some of this evidence is contradictory. No studies of iron status and blood lead levels in children have accounted for environmental lead contamination and, therefore, the source of their exposure. Thus, no studies have directly determined whether iron deficiency modifies the relationship of environmental lead and blood lead. In this study, we compared blood lead levels of iron-deficient and iron-replete children living in low, medium, or highly contaminated environments. Measurements of lead in paint, soil, dust, and blood, age of housing, and iron status were collected from 319 children ages 1-5. We developed two lead exposure factors to summarize the correlated exposure variables: Factor 1 summarized all environmental measures, and Factor 2 was weighted for lead loading of house dust. The geometric mean blood lead level was 4.9 microg/dL; 14% exceeded 10 microg/dL. Many of the children were iron deficient (24% with ferritin < 12 ng/dL). Seventeen percent of soil leads exceeded 500 microg/g, and 23% and 63% of interior and exterior paint samples exceeded 5,000 microg/g. The unadjusted geometric mean blood lead level for iron-deficient children was higher by 1 microg/dL; this difference was greater (1.8 microg/dL) after excluding Asians. Blood lead levels were higher for iron-deficient children for each tertile of exposure as estimated by Factors 1 and 2 for non-Asian children. Elevated blood lead among iron-deficient children persisted after adjusting for potential confounders by multivariate regression; the largest difference in blood lead levels between iron-deficient and -replete children, approximately 3 microg/dL, was among those living in the most contaminated environments. Asian children had a paradoxical association of sufficient iron status and higher blood lead level, which warrants further investigation. Improving iron status, along with reducing exposures, may help reduce blood lead levels among most children, especially those living in the most contaminated environments.

Full Text

The Full Text of this article is available as a PDF (600.1 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Acierno R. A., Kilpatrick D. G., Resnick H. S., Saunders B. E., Best C. L. Violent assault, posttraumatic stress disorder, and depression. Risk factors for cigarette use among adult women. Behav Modif. 1996 Oct;20(4):363–384. doi: 10.1177/01454455960204001. [DOI] [PubMed] [Google Scholar]
  2. Adler N. E., Boyce T., Chesney M. A., Cohen S., Folkman S., Kahn R. L., Syme S. L. Socioeconomic status and health. The challenge of the gradient. Am Psychol. 1994 Jan;49(1):15–24. doi: 10.1037//0003-066x.49.1.15. [DOI] [PubMed] [Google Scholar]
  3. Ballew C., Bowman B. Recommending calcium to reduce lead toxicity in children: a critical review. Nutr Rev. 2001 Mar;59(3 Pt 1):71–79. doi: 10.1111/j.1753-4887.2001.tb06991.x. [DOI] [PubMed] [Google Scholar]
  4. Barton J. C., Conrad M. E., Nuby S., Harrison L. Effects of iron on the absorption and retention of lead. J Lab Clin Med. 1978 Oct;92(4):536–547. [PubMed] [Google Scholar]
  5. Baum A. Stress, intrusive imagery, and chronic distress. Health Psychol. 1990;9(6):653–675. doi: 10.1037//0278-6133.9.6.653. [DOI] [PubMed] [Google Scholar]
  6. Beckham J. C., Roodman A. A., Shipley R. H., Hertzberg M. A., Cunha G. H., Kudler H. S., Levin E. D., Rose J. E., Fairbank J. A. Smoking in Vietnam combat veterans with post-traumatic stress disorder. J Trauma Stress. 1995 Jul;8(3):461–472. doi: 10.1007/BF02102970. [DOI] [PubMed] [Google Scholar]
  7. Blake K. C., Mann M. Effect of calcium and phosphorus on the gastrointestinal absorption of 203Pb in man. Environ Res. 1983 Feb;30(1):188–194. doi: 10.1016/0013-9351(83)90179-2. [DOI] [PubMed] [Google Scholar]
  8. Boxer G. H., Carson J., Miller B. D. Neglect contributing to tertiary hospitalization in childhood asthma. Child Abuse Negl. 1988;12(4):491–501. doi: 10.1016/0145-2134(88)90066-x. [DOI] [PubMed] [Google Scholar]
  9. Braun-Fahrländer C., Ackermann-Liebrich U., Schwartz J., Gnehm H. P., Rutishauser M., Wanner H. U. Air pollution and respiratory symptoms in preschool children. Am Rev Respir Dis. 1992 Jan;145(1):42–47. doi: 10.1164/ajrccm/145.1.42. [DOI] [PubMed] [Google Scholar]
  10. Brody D. J., Pirkle J. L., Kramer R. A., Flegal K. M., Matte T. D., Gunter E. W., Paschal D. C. Blood lead levels in the US population. Phase 1 of the Third National Health and Nutrition Examination Survey (NHANES III, 1988 to 1991) JAMA. 1994 Jul 27;272(4):277–283. doi: 10.1001/jama.272.4.277. [DOI] [PubMed] [Google Scholar]
  11. Brosschot J. F., Benschop R. J., Godaert G. L., Olff M., De Smet M., Heijnen C. J., Ballieux R. E. Influence of life stress on immunological reactivity to mild psychological stress. Psychosom Med. 1994 May-Jun;56(3):216–224. doi: 10.1097/00006842-199405000-00007. [DOI] [PubMed] [Google Scholar]
  12. Busse W. W., Gern J. E., Dick E. C. The role of respiratory viruses in asthma. Ciba Found Symp. 1997;206:208–219. doi: 10.1002/9780470515334.ch13. [DOI] [PubMed] [Google Scholar]
  13. Busse W. W., Kiecolt-Glaser J. K., Coe C., Martin R. J., Weiss S. T., Parker S. R. NHLBI Workshop summary. Stress and asthma. Am J Respir Crit Care Med. 1995 Jan;151(1):249–252. doi: 10.1164/ajrccm.151.1.7812562. [DOI] [PubMed] [Google Scholar]
  14. Centers for Disease Control (CDC) CDC criteria for anemia in children and childbearing-aged women. MMWR Morb Mortal Wkly Rep. 1989 Jun 9;38(22):400–404. [PubMed] [Google Scholar]
  15. Centers for Disease Control and Prevention (CDC) Update: blood lead levels--United States, 1991-1994. MMWR Morb Mortal Wkly Rep. 1997 Feb 21;46(7):141–146. [PubMed] [Google Scholar]
  16. Cohen S., Tyrrell D. A., Smith A. P. Psychological stress and susceptibility to the common cold. N Engl J Med. 1991 Aug 29;325(9):606–612. doi: 10.1056/NEJM199108293250903. [DOI] [PubMed] [Google Scholar]
  17. Conrad M. E., Umbreit J. N., Moore E. G. A role for mucin in the absorption of inorganic iron and other metal cations. A study in rats. Gastroenterology. 1991 Jan;100(1):129–136. doi: 10.1016/0016-5085(91)90592-9. [DOI] [PubMed] [Google Scholar]
  18. Conrad M. E., Umbreit J. N., Moore E. G., Rodning C. R. Newly identified iron-binding protein in human duodenal mucosa. Blood. 1992 Jan 1;79(1):244–247. [PubMed] [Google Scholar]
  19. Cook J. D., Skikne B. S. Iron deficiency: definition and diagnosis. J Intern Med. 1989 Nov;226(5):349–355. doi: 10.1111/j.1365-2796.1989.tb01408.x. [DOI] [PubMed] [Google Scholar]
  20. Dallman P. R., Siimes M. A., Stekel A. Iron deficiency in infancy and childhood. Am J Clin Nutr. 1980 Jan;33(1):86–118. doi: 10.1093/ajcn/33.1.86. [DOI] [PubMed] [Google Scholar]
  21. Dallman P. R., Yip R., Johnson C. Prevalence and causes of anemia in the United States, 1976 to 1980. Am J Clin Nutr. 1984 Mar;39(3):437–445. doi: 10.1093/ajcn/39.3.437. [DOI] [PubMed] [Google Scholar]
  22. Deinard A. S., Schwartz S., Yip R. Developmental changes in serum ferritin and erythrocyte protoporphyrin in normal (nonanemic) children. Am J Clin Nutr. 1983 Jul;38(1):71–76. doi: 10.1093/ajcn/38.1.71. [DOI] [PubMed] [Google Scholar]
  23. Donovan C. E., Finn P. W. Immune mechanisms of childhood asthma. Thorax. 1999 Oct;54(10):938–946. doi: 10.1136/thx.54.10.938. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Eden A. N., Mir M. A. Iron deficiency in 1- to 3-year-old children. A pediatric failure? Arch Pediatr Adolesc Med. 1997 Oct;151(10):986–988. doi: 10.1001/archpedi.1997.02170470020003. [DOI] [PubMed] [Google Scholar]
  25. Federman D. G., Kirsner R. S., Federman G. S. Pica: are you hungry for the facts? Conn Med. 1997 Apr;61(4):207–209. [PubMed] [Google Scholar]
  26. Feigelman W., Gorman B. Toward explaining the higher incidence of cigarette smoking among black Americans. J Psychoactive Drugs. 1989 Jul-Sep;21(3):299–305. doi: 10.1080/02791072.1989.10472171. [DOI] [PubMed] [Google Scholar]
  27. Fitzpatrick K. M., Boldizar J. P. The prevalence and consequences of exposure to violence among African-American youth. J Am Acad Child Adolesc Psychiatry. 1993 Mar;32(2):424–430. doi: 10.1097/00004583-199303000-00026. [DOI] [PubMed] [Google Scholar]
  28. Flanagan P. R., Chamberlain M. J., Valberg L. S. The relationship between iron and lead absorption in humans. Am J Clin Nutr. 1982 Nov;36(5):823–829. doi: 10.1093/ajcn/36.5.823. [DOI] [PubMed] [Google Scholar]
  29. Flanagan P. R., Hamilton D. L., Haist J., Valberg L. S. Interrelationships between iron and lead absorption in iron-deficient mice. Gastroenterology. 1979 Nov;77(5):1074–1081. [PubMed] [Google Scholar]
  30. Fleming A. W., Sterling-Scott R. P., Carabello G., Imari-Williams I., Allmond B., Foster R. S., Kennedy F., Shoemaker W. C. Injury and violence in Los Angeles. Impact on access to health care and surgical education. Arch Surg. 1992 Jun;127(6):671–676. doi: 10.1001/archsurg.1992.01420060037007. [DOI] [PubMed] [Google Scholar]
  31. Fong R. L. Violence as a barrier to compliance for the hypertensive urban African American. J Natl Med Assoc. 1995 Mar;87(3):203–207. [PMC free article] [PubMed] [Google Scholar]
  32. Gellhorn E. The neurophysiological basis of anxiety: a hypothesis. Perspect Biol Med. 1965 Summer;8(4):488–515. doi: 10.1353/pbm.1965.0058. [DOI] [PubMed] [Google Scholar]
  33. Gergen P. J., Weiss K. B. Changing patterns of asthma hospitalization among children: 1979 to 1987. JAMA. 1990 Oct 3;264(13):1688–1692. [PubMed] [Google Scholar]
  34. Gortmaker S. L., Must A., Sobol A. M., Peterson K., Colditz G. A., Dietz W. H. Television viewing as a cause of increasing obesity among children in the United States, 1986-1990. Arch Pediatr Adolesc Med. 1996 Apr;150(4):356–362. doi: 10.1001/archpedi.1996.02170290022003. [DOI] [PubMed] [Google Scholar]
  35. Graham N. M., Douglas R. M., Ryan P. Stress and acute respiratory infection. Am J Epidemiol. 1986 Sep;124(3):389–401. doi: 10.1093/oxfordjournals.aje.a114409. [DOI] [PubMed] [Google Scholar]
  36. Gustafsson P. A., Kjellman N. I., Ludvigsson J., Cederblad M. Asthma and family interaction. Arch Dis Child. 1987 Mar;62(3):258–263. doi: 10.1136/adc.62.3.258. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Hammad T. A., Sexton M., Langenberg P. Relationship between blood lead and dietary iron intake in preschool children. A cross-sectional study. Ann Epidemiol. 1996 Jan;6(1):30–33. doi: 10.1016/1047-2797(95)00097-6. [DOI] [PubMed] [Google Scholar]
  38. Herman A. A. Political violence, health, and health services in South Africa. Am J Public Health. 1988 Jul;78(7):767–768. doi: 10.2105/ajph.78.7.767. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Hershko C., Konijn A. M., Moreb J., Link G., Grauer F., Weissenberg E. Iron depletion and blood lead levels in a population with endemic lead poisoning. Isr J Med Sci. 1984 Nov;20(11):1039–1043. [PubMed] [Google Scholar]
  40. Hsieh L. L., Liou S. H., Chen Y. H., Tsai L. C., Yang T., Wu T. N. Association between aminolevulinate dehydrogenase genotype and blood lead levels in Taiwan. J Occup Environ Med. 2000 Feb;42(2):151–155. doi: 10.1097/00043764-200002000-00009. [DOI] [PubMed] [Google Scholar]
  41. Idjradinata P., Pollitt E. Reversal of developmental delays in iron-deficient anaemic infants treated with iron. Lancet. 1993 Jan 2;341(8836):1–4. doi: 10.1016/0140-6736(93)92477-b. [DOI] [PubMed] [Google Scholar]
  42. Johnson N. E., Tenuta K. Diets and lead blood levels of children who practice pica. Environ Res. 1979 Apr;18(2):369–376. doi: 10.1016/0013-9351(79)90113-0. [DOI] [PubMed] [Google Scholar]
  43. Kauffman K. S. Center as haven: findings of an urban ethnography. Nurs Res. 1995 Jul-Aug;44(4):231–236. [PubMed] [Google Scholar]
  44. Kawachi I., Kennedy B. P. Income inequality and health: pathways and mechanisms. Health Serv Res. 1999 Apr;34(1 Pt 2):215–227. [PMC free article] [PubMed] [Google Scholar]
  45. Kawachi I., Kennedy B. P., Wilkinson R. G. Crime: social disorganization and relative deprivation. Soc Sci Med. 1999 Mar;48(6):719–731. doi: 10.1016/s0277-9536(98)00400-6. [DOI] [PubMed] [Google Scholar]
  46. Krause N. Stress and isolation from close ties in later life. J Gerontol. 1991 Jul;46(4):S183–S194. doi: 10.1093/geronj/46.4.s183. [DOI] [PubMed] [Google Scholar]
  47. Lacey E. P. Broadening the perspective of pica: literature review. Public Health Rep. 1990 Jan-Feb;105(1):29–35. [PMC free article] [PubMed] [Google Scholar]
  48. Laraque D., McCormick M., Norman M., Taylor A., Weller S. C., Karp J. Blood lead, calcium status, and behavior in preschool children. Am J Dis Child. 1990 Feb;144(2):186–189. doi: 10.1001/archpedi.1990.02150260066030. [DOI] [PubMed] [Google Scholar]
  49. Lozoff B., Brittenham G. M., Viteri F. E., Wolf A. W., Urrutia J. J. Developmental deficits in iron-deficient infants: effects of age and severity of iron lack. J Pediatr. 1982 Dec;101(6):948–952. doi: 10.1016/s0022-3476(82)80016-4. [DOI] [PubMed] [Google Scholar]
  50. Lucas S. R., Sexton M., Langenberg P. Relationship between blood lead and nutritional factors in preschool children: a cross-sectional study. Pediatrics. 1996 Jan;97(1):74–78. [PubMed] [Google Scholar]
  51. Madhavan S., Rosenman K. D., Shehata T. Lead in soil: recommended maximum permissible levels. Environ Res. 1989 Jun;49(1):136–142. doi: 10.1016/s0013-9351(89)80028-3. [DOI] [PubMed] [Google Scholar]
  52. Mahaffey K. R. Environmental lead toxicity: nutrition as a component of intervention. Environ Health Perspect. 1990 Nov;89:75–78. doi: 10.1289/ehp.908975. [DOI] [PMC free article] [PubMed] [Google Scholar]
  53. Mahaffey K. R., Gartside P. S., Glueck C. J. Blood lead levels and dietary calcium intake in 1- to 11-year-old children: the Second National Health and Nutrition Examination Survey, 1976 to 1980. Pediatrics. 1986 Aug;78(2):257–262. [PubMed] [Google Scholar]
  54. Mannino D. M., Homa D. M., Pertowski C. A., Ashizawa A., Nixon L. L., Johnson C. A., Ball L. B., Jack E., Kang D. S. Surveillance for asthma--United States, 1960-1995. MMWR CDC Surveill Summ. 1998 Apr 24;47(1):1–27. [PubMed] [Google Scholar]
  55. Markowitz M. E., Rosen J. F., Bijur P. E. Effects of iron deficiency on lead excretion in children with moderate lead intoxication. J Pediatr. 1990 Mar;116(3):360–364. doi: 10.1016/s0022-3476(05)82821-5. [DOI] [PubMed] [Google Scholar]
  56. Martinez F. D., Cline M., Burrows B. Increased incidence of asthma in children of smoking mothers. Pediatrics. 1992 Jan;89(1):21–26. [PubMed] [Google Scholar]
  57. McEwen B. S., Biron C. A., Brunson K. W., Bulloch K., Chambers W. H., Dhabhar F. S., Goldfarb R. H., Kitson R. P., Miller A. H., Spencer R. L. The role of adrenocorticoids as modulators of immune function in health and disease: neural, endocrine and immune interactions. Brain Res Brain Res Rev. 1997 Feb;23(1-2):79–133. doi: 10.1016/s0165-0173(96)00012-4. [DOI] [PubMed] [Google Scholar]
  58. Miller G. D., Massaro T. F., Massaro E. J. Interactions between lead and essential elements: a review. Neurotoxicology. 1990 Spring;11(1):99–119. [PubMed] [Google Scholar]
  59. Nadel J. A., Barnes P. J. Autonomic regulation of the airways. Annu Rev Med. 1984;35:451–467. doi: 10.1146/annurev.me.35.020184.002315. [DOI] [PubMed] [Google Scholar]
  60. Needleman H. L., Gatsonis C. A. Low-level lead exposure and the IQ of children. A meta-analysis of modern studies. JAMA. 1990 Feb 2;263(5):673–678. [PubMed] [Google Scholar]
  61. Needleman H. L., Gunnoe C., Leviton A., Reed R., Peresie H., Maher C., Barrett P. Deficits in psychologic and classroom performance of children with elevated dentine lead levels. N Engl J Med. 1979 Mar 29;300(13):689–695. doi: 10.1056/NEJM197903293001301. [DOI] [PubMed] [Google Scholar]
  62. Osofsky J. D., Wewers S., Hann D. M., Fick A. C. Chronic community violence: what is happening to our children? Psychiatry. 1993 Feb;56(1):36–45. doi: 10.1080/00332747.1993.11024619. [DOI] [PubMed] [Google Scholar]
  63. Pike J. L., Smith T. L., Hauger R. L., Nicassio P. M., Patterson T. L., McClintick J., Costlow C., Irwin M. R. Chronic life stress alters sympathetic, neuroendocrine, and immune responsivity to an acute psychological stressor in humans. Psychosom Med. 1997 Jul-Aug;59(4):447–457. doi: 10.1097/00006842-199707000-00015. [DOI] [PubMed] [Google Scholar]
  64. Pirkle J. L., Brody D. J., Gunter E. W., Kramer R. A., Paschal D. C., Flegal K. M., Matte T. D. The decline in blood lead levels in the United States. The National Health and Nutrition Examination Surveys (NHANES) JAMA. 1994 Jul 27;272(4):284–291. [PubMed] [Google Scholar]
  65. Pollitt E., Leibel R. L. Iron deficiency and behavior. J Pediatr. 1976 Mar;88(3):372–381. doi: 10.1016/s0022-3476(76)80250-8. [DOI] [PubMed] [Google Scholar]
  66. Rabkin J. G., Struening E. L. Live events, stress, and illness. Science. 1976 Dec 3;194(4269):1013–1020. doi: 10.1126/science.790570. [DOI] [PubMed] [Google Scholar]
  67. Ragan H. A. Effects of iron deficiency on the absorption and distribution of lead and cadmium in rats. J Lab Clin Med. 1977 Oct;90(4):700–706. [PubMed] [Google Scholar]
  68. Reijneveld S. A. The impact of individual and area characteristics on urban socioeconomic differences in health and smoking. Int J Epidemiol. 1998 Feb;27(1):33–40. doi: 10.1093/ije/27.1.33. [DOI] [PubMed] [Google Scholar]
  69. Robicsek F., Ribbeck B., Walker L. G., Thomason M. H., Hollenbeck J. I., Baker J. W. The cost of violence. The economy of health care delivery for non-accidental trauma in an urban southeastern community. N C Med J. 1993 Nov;54(11):578–582. [PubMed] [Google Scholar]
  70. Romano P. S., Bloom J., Syme S. L. Smoking, social support, and hassles in an urban African-American community. Am J Public Health. 1991 Nov;81(11):1415–1422. doi: 10.2105/ajph.81.11.1415. [DOI] [PMC free article] [PubMed] [Google Scholar]
  71. Ruff H. A., Markowitz M. E., Bijur P. E., Rosen J. F. Relationships among blood lead levels, iron deficiency, and cognitive development in two-year-old children. Environ Health Perspect. 1996 Feb;104(2):180–185. doi: 10.1289/ehp.96104180. [DOI] [PMC free article] [PubMed] [Google Scholar]
  72. Sampson R. J., Raudenbush S. W., Earls F. Neighborhoods and violent crime: a multilevel study of collective efficacy. Science. 1997 Aug 15;277(5328):918–924. doi: 10.1126/science.277.5328.918. [DOI] [PubMed] [Google Scholar]
  73. Sargent J. D., Dalton M. A., O'Connor G. T., Olmstead E. M., Klein R. Z. Randomized trial of calcium glycerophosphate-supplemented infant formula to prevent lead absorption. Am J Clin Nutr. 1999 Jun;69(6):1224–1230. doi: 10.1093/ajcn/69.6.1224. [DOI] [PubMed] [Google Scholar]
  74. Sargent J. D., Stukel T. A., Dalton M. A., Freeman J. L., Brown M. J. Iron deficiency in Massachusetts communities: Socioeconomic and demographic risk factors among children. Am J Public Health. 1996 Apr;86(4):544–550. doi: 10.2105/ajph.86.4.544. [DOI] [PMC free article] [PubMed] [Google Scholar]
  75. Schwartz B. S., Stewart W. F., Kelsey K. T., Simon D., Park S., Links J. M., Todd A. C. Associations of tibial lead levels with BsmI polymorphisms in the vitamin D receptor in former organolead manufacturing workers. Environ Health Perspect. 2000 Mar;108(3):199–203. doi: 10.1289/ehp.00108199. [DOI] [PMC free article] [PubMed] [Google Scholar]
  76. Schwartz J., Angle C., Pitcher H. Relationship between childhood blood lead levels and stature. Pediatrics. 1986 Mar;77(3):281–288. [PubMed] [Google Scholar]
  77. Schwartz J., Otto D. Blood lead, hearing thresholds, and neurobehavioral development in children and youth. Arch Environ Health. 1987 May-Jun;42(3):153–160. doi: 10.1080/00039896.1987.9935814. [DOI] [PubMed] [Google Scholar]
  78. Sheehan K., DiCara J. A., LeBailly S., Christoffel K. K. Children's exposure to violence in an urban setting. Arch Pediatr Adolesc Med. 1997 May;151(5):502–504. doi: 10.1001/archpedi.1997.02170420072012. [DOI] [PubMed] [Google Scholar]
  79. Siimes M. A., Addiego J. E., Jr, Dallman P. R. Ferritin in serum: diagnosis of iron deficiency and iron overload in infants and children. Blood. 1974 Apr;43(4):581–590. [PubMed] [Google Scholar]
  80. Six K. M., Goyer R. A. The influence of iron deficiency on tissue content and toxicity of ingested lead in the rat. J Lab Clin Med. 1972 Jan;79(1):128–136. [PubMed] [Google Scholar]
  81. Sporik R., Holgate S. T., Platts-Mills T. A., Cogswell J. J. Exposure to house-dust mite allergen (Der p I) and the development of asthma in childhood. A prospective study. N Engl J Med. 1990 Aug 23;323(8):502–507. doi: 10.1056/NEJM199008233230802. [DOI] [PubMed] [Google Scholar]
  82. Stenius-Aarniala B., Poussa T., Kvarnström J., Grönlund E. L., Ylikahri M., Mustajoki P. Immediate and long term effects of weight reduction in obese people with asthma: randomised controlled study. BMJ. 2000 Mar 25;320(7238):827–832. doi: 10.1136/bmj.320.7238.827. [DOI] [PMC free article] [PubMed] [Google Scholar]
  83. Sternberg E. M. Neural-immune interactions in health and disease. J Clin Invest. 1997 Dec 1;100(11):2641–2647. doi: 10.1172/JCI119807. [DOI] [PMC free article] [PubMed] [Google Scholar]
  84. Stringham P. Violence anticipatory guidance. Pediatr Clin North Am. 1998 Apr;45(2):439–448. doi: 10.1016/s0031-3955(05)70018-3. [DOI] [PubMed] [Google Scholar]
  85. Strunk R. C., Mrazek D. A., Fuhrmann G. S., LaBrecque J. F. Physiologic and psychological characteristics associated with deaths due to asthma in childhood. A case-controlled study. JAMA. 1985 Sep 6;254(9):1193–1198. [PubMed] [Google Scholar]
  86. Sutton P. M., Athanasoulis M., Flessel P., Guirguis G., Haan M., Schlag R., Goldman L. R. Lead levels in the household environment of children in three high-risk communities in California. Environ Res. 1995 Jan;68(1):45–57. doi: 10.1006/enrs.1995.1007. [DOI] [PubMed] [Google Scholar]
  87. Taylor L., Zuckerman B., Harik V., Groves B. M. Witnessing violence by young children and their mothers. J Dev Behav Pediatr. 1994 Apr;15(2):120–123. [PubMed] [Google Scholar]
  88. Taylor S. E., Repetti R. L., Seeman T. Health psychology: what is an unhealthy environment and how does it get under the skin? Annu Rev Psychol. 1997;48:411–447. doi: 10.1146/annurev.psych.48.1.411. [DOI] [PubMed] [Google Scholar]
  89. Vingerhoets A. J. The role of the parasympathetic division of the autonomic nervous system in stress and the emotions. Int J Psychosom. 1985;32(3):28–34. [PubMed] [Google Scholar]
  90. Wallace D., Wallace R. Scales of geography, time, and population: the study of violence as a public health problem. Am J Public Health. 1998 Dec;88(12):1853–1858. doi: 10.2105/ajph.88.12.1853. [DOI] [PMC free article] [PubMed] [Google Scholar]
  91. Wasserman G. A., Graziano J. H., Factor-Litvak P., Popovac D., Morina N., Musabegovic A., Vrenezi N., Capuni-Paracka S., Lekic V., Preteni-Redjepi E. Consequences of lead exposure and iron supplementation on childhood development at age 4 years. Neurotoxicol Teratol. 1994 May-Jun;16(3):233–240. doi: 10.1016/0892-0362(94)90044-2. [DOI] [PubMed] [Google Scholar]
  92. Wasserman G., Graziano J. H., Factor-Litvak P., Popovac D., Morina N., Musabegovic A., Vrenezi N., Capuni-Paracka S., Lekic V., Preteni-Redjepi E. Independent effects of lead exposure and iron deficiency anemia on developmental outcome at age 2 years. J Pediatr. 1992 Nov;121(5 Pt 1):695–703. doi: 10.1016/s0022-3476(05)81895-5. [DOI] [PubMed] [Google Scholar]
  93. Watson W. S., Hume R., Moore M. R. Oral absorption of lead and iron. Lancet. 1980 Aug 2;2(8188):236–237. doi: 10.1016/s0140-6736(80)90124-5. [DOI] [PubMed] [Google Scholar]
  94. Watson W. S., Morrison J., Bethel M. I., Baldwin N. M., Lyon D. T., Dobson H., Moore M. R., Hume R. Food iron and lead absorption in humans. Am J Clin Nutr. 1986 Aug;44(2):248–256. doi: 10.1093/ajcn/44.2.248. [DOI] [PubMed] [Google Scholar]
  95. Weiss K. B., Gergen P. J., Crain E. F. Inner-city asthma. The epidemiology of an emerging US public health concern. Chest. 1992 Jun;101(6 Suppl):362S–367S. doi: 10.1378/chest.101.6.362s. [DOI] [PubMed] [Google Scholar]
  96. Wetmur J. G., Lehnert G., Desnick R. J. The delta-aminolevulinate dehydratase polymorphism: higher blood lead levels in lead workers and environmentally exposed children with the 1-2 and 2-2 isozymes. Environ Res. 1991 Dec;56(2):109–119. doi: 10.1016/s0013-9351(05)80001-5. [DOI] [PubMed] [Google Scholar]
  97. Wright R. J., Rodriguez M., Cohen S. Review of psychosocial stress and asthma: an integrated biopsychosocial approach. Thorax. 1998 Dec;53(12):1066–1074. doi: 10.1136/thx.53.12.1066. [DOI] [PMC free article] [PubMed] [Google Scholar]
  98. Wright R. O., Shannon M. W., Wright R. J., Hu H. Association between iron deficiency and low-level lead poisoning in an urban primary care clinic. Am J Public Health. 1999 Jul;89(7):1049–1053. doi: 10.2105/ajph.89.7.1049. [DOI] [PMC free article] [PubMed] [Google Scholar]
  99. Yip R., Dallman P. R. Developmental changes in erythrocyte protoporphyrin: roles of iron deficiency and lead toxicity. J Pediatr. 1984 May;104(5):710–713. doi: 10.1016/s0022-3476(84)80949-x. [DOI] [PubMed] [Google Scholar]
  100. Yip R., Johnson C., Dallman P. R. Age-related changes in laboratory values used in the diagnosis of anemia and iron deficiency. Am J Clin Nutr. 1984 Mar;39(3):427–436. doi: 10.1093/ajcn/39.3.427. [DOI] [PubMed] [Google Scholar]
  101. Yip R., Norris T. N., Anderson A. S. Iron status of children with elevated blood lead concentrations. J Pediatr. 1981 Jun;98(6):922–925. doi: 10.1016/s0022-3476(81)80589-6. [DOI] [PubMed] [Google Scholar]
  102. Zapata B. C., Rebolledo A., Atalah E., Newman B., King M. C. The influence of social and political violence on the risk of pregnancy complications. Am J Public Health. 1992 May;82(5):685–690. doi: 10.2105/ajph.82.5.685. [DOI] [PMC free article] [PubMed] [Google Scholar]
  103. Ziegler E. E., Edwards B. B., Jensen R. L., Mahaffey K. R., Fomon S. J. Absorption and retention of lead by infants. Pediatr Res. 1978 Jan;12(1):29–34. doi: 10.1203/00006450-197801000-00008. [DOI] [PubMed] [Google Scholar]
  104. Ziemsen B., Angerer J., Lehnert G., Benkmann H. G., Goedde H. W. Polymorphism of delta-aminolevulinic acid dehydratase in lead-exposed workers. Int Arch Occup Environ Health. 1986;58(3):245–247. doi: 10.1007/BF00432107. [DOI] [PubMed] [Google Scholar]

Articles from Environmental Health Perspectives are provided here courtesy of National Institute of Environmental Health Sciences

RESOURCES