Document 828q80ENRm8XbY2R2No4NeoEK

CENTER FOR DISEASE CONTROL MORBIDITY AND MORTALITY WEEKLY REPORT February 24,1978 / Vol. 27/ No. 8 Epidemiologic Notes and Reports 57 Follow-up on Lead Poisoning -- Texas International Notes 58 Yellow Fever Vaccine -- United States 58 Quarantine Measures 64 Influenza -- Worldwide Current Trends 63 Tuberculosis -- United States, 1977 63 Primary and Secondary Syphilis -- United States, December 1977 Epidemiologic Notes and Reports '.Fo'Uow-up on Lead Poisoning -- Texas Since 1972, investigations of the effects of industrial lead emissions on El Paso, Texas, residents, in particular children living near an ore smelter close to the Mexican border, have been conducted bv CDC and the El Paso CityCounty Health Department (7-3). This report summarizes data from the latest follow-up investigation undertaken in November 1977. Marked decreases were found in lead con centrations in children's blood specimens, and these decreases were paralleled by decreased concentrations in air, household dust, and soil samples. The previous investigations in El Paso in 1972 and simi lar ones in Ciudad Juarez, Mexico, in 1974 (4) showed that more than 56% of children 1-T9 years old residing within 1.6 km of the smelter had blood lead levels >40 Mg/100 ml.* Since then, engineering improvements undertaken at the smelter have substantially reduced lead emissions; for example, mean air lead concentrations at a site 4 km from the smelter decreased from 4.4 jug/m3 in 1970 to 1.3 Mg/m3 in 1976. To evaluate the impact of these environmental improve ments on children's blood lead levels, 140 children 1-19 years old living within 2 km of the smelter were tested. These children represented 55 (82%) of the 67 households with children that lay within the survey area. Dust and soil lead concentrations in samples taken at these homes in 1977 showed marked decreases Compared with the concen trations found in 1972 (mean concentrations: dust 22,191 ppm in 1972 vs 1,479 ppm in 1077; spil 1,791 ppm in 1972 vs 427 ppm in 1977) and were similar in magnitude to con centrations noted in 1972 in homes located 3.3-6.4 km from the smelter. Similarly, a comparison of children's blood lead levels determined in 1977 with those obtained in 1972 showed that mean concentrations had dropped 35%. Likewise, the percentage of children with blood concentrations >40 Mg/ 100 ml dropped 18%, while those with concentrations >30 ptg/100 ml dropped 39% (Table 1). Reported by BF Rosenbium. MO, R Kretzschmar, R Candelaria, J Hubert, El Faso City-County Health Dept; J Bradley, MD, Texas Public Health Region 3; CR Webb, Jr, MD, State Epidemiologist, * Blood lead levels >30 ug/100 ml indicate excessive lead absorp tion (5). Texas Dept of Health; Toxicology Br, Clinical Chemistry Div, Bur of Laboratories, Special Studies Br. Chronic Diseases Div, Bur of Epidemiology, CDC. TABLE 1. Bipod tead levels in children 1-19 years old, living 1-2 km from an ore smelter, El Paso, Texas, 1972 and 1977 No. of children Mean age (yrs) Mean blood lead (pg/IOQ mil No. (%) with blood toad >40 jug/100 ml No. (%) with blood lead >30 pg/100 ml 1972 96 8.9 31.22 18 (19%) 47 (49%) 1977 137 9.3 20.14 2 (1%) 14 (10%) Editorial Note: Despite the findings noted in this study, El Paso continues to have one of the highest air lead con centrations in the United States, and air lead levels at a number of sites there exceed EPA's proposed standard of 1.5 Mg/m3 (3). in addition, preliminary air monitoring mea surements from 1977 indicate that air lead concentrations in the city are currently on the increase. The 10% prevalence of blood lead levels >30 Mg/100 ml found in the El Paso children living near the smelter is still unacceptably high. By comparison, lead screening programs in DHEW Region VI, which includes Texas, have shown that only 5% of screened children in targeted high-riskareas have lead levels >30 Mg/100 ml (7). Furthermore, the risk of increased lead absorption in children in Mexico, who live much closer to the smelter than the El Paso children evalu ated, is unknown, but Mexican health authorities are plan ning to conduct follow-up studies later this year. References 1. MMWR 22.405-407,1973 2. MMWR 23:28, 157-159,1974 3. Landrigan P4, Getilbach SH, Rpsenblum BF, et al: Epidemic lead absorption near an ore smelter. N Engl J Med 292:1-7, 1975 4. Ordonez BR, Romero CR, Mora R: investigation epidemiologies sobre niveles de plorno en la poblation infantil y en el medio am bient domieiliario de Ciudad Ju.arez, Chihuahua, en relation con una fundicion de El Paso. Texas. Boletin de la Oficina Sanitaria Panamericana 80:303-317,1976 5. Center for Disease Control: increased Lead Absorption and Lead Poisoning in Young Children. Atlanta, CDC, 1975 6. U.S. Environmental Protection Agency: National Ambient Air Quality Standard for Lead. Notice of Proposed Rulemaking (40 CFR Part 50) (FRL 821-4). Research Triangle Park, North Carolina, EPA, 1977 7. MMWR 26:367,1977 U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE / PUBLIC HEALTH SERVICE TEH 0532415