Children’s Blood Lead Concentrations from 1988 to 2015 in Mexico City: The Contribution of Lead in Air and Traditional Lead-Glazed Ceramics

Abstract

Despite the removal of lead from gasoline in 1997, elevated blood lead levels (BLLs) > 5 µg/dL are still detectable in children living in Mexico City. The use of lead-glazed ceramics may explain these persistent exposure levels. Mexico lacks a national surveillance program for BLL, but temporal trends can be derived from epidemiological studies. With this approach, we leveraged a series of birth cohorts to report BLL trends from 1987 to 2002 and expanded our analysis to 2015. Data were from 1–5-year-old children from five Mexico City cohorts followed between 1988 and 2015. BLLs are reported on 1963 children, who contributed 4975 BLLs. We estimated the trend of mean BLL, which decreased from 15.7 µg/dL in 1988, to 7.8 µg/dL in 1998 (a year after the total ban of lead in gasoline), to 1.96 µg/dL in 2015. The proportion of BLL ≥ 5 µg/dL decreased from 92% (1988–1998) to 8% (2008–2015). The use of lead-glazed ceramics was associated with an 11% increase in BLLs throughout the study period. Replacing lead-based glazes in traditional ceramics may be the key to further reducing exposure, but this presents challenges, as it involves a cultural tradition deeply rooted in Mexico. In addition, the creation of a rigorous, standardized, and on-going surveillance program of BLL is necessary for identifying vulnerable populations.

Reporte nacional de niveles de plomo en sangre y uso de barro vidriado en población infantil vulnerable

“…En conclusión, aunque los niveles de PbS en la población infantil han disminuido en los últimos 40 años, 46 aún se tienen prevalencias de niveles elevados sustancialmente más altas que en otros países del continente. En México se han implementado estrategias exitosas para reducir los niveles de PbS, como lo fue la remoción de Pb de las gasolinas; sin embargo, México continúa con una fuente de exposición altamente salud pública de méxico / vol.…”

Lead Concentrations in Mexican Candy: A Follow-Up Report

“…In response, candy producers with large exports implemented stricter quality controls and lead was no longer detected in the wrappers. However, a well-known source of lead exposure in Mexico is the use of traditional lead-glazed low-temperature ceramics to prepare, serve and store food [16]. Lead will leach into food that is in contact with the surface of these ceramics, particularly acidic food such as tamarind candy.…”

“…Lead will leach into food that is in contact with the surface of these ceramics, particularly acidic food such as tamarind candy. This type of ceramic is widely used in Mexico and is linked to cultural identity [16]. Still today, artisans lack access to high temperature kilns or adequate lead-free glazes to make a change to producing safer ceramics economically feasible, rendering a complex public health challenge in Mexico.…”

“…The prevalence of blood lead levels ≥5µg/dL (the current blood lead level limit established by the Mexican Health System, and in accordance to the U.S. CDC) was 21.8% and there was a strong association between the use of lead-glazed ceramics and higher blood lead levels [20,21]. Results from epidemiologic studies have shown that overall and across the years, the percentages of Mexican children younger than 5 years old with blood lead concentrations ≥5µg/dL range from 8% -15% and average levels in both children and pregnant women remain nearly 3 times higher than those estimated in the US during the same years [16,22,23]. A targeted monitoring system of blood lead concentrations representative of the Mexican population, similar to the National Health and Nutrition Examination Study (NHANES) in the U.S, would begin to provide information needed to understand the need for national prevention of lead exposure across all age groups but especially in vulnerable populations like children and pregnant women.…”

Lead Exposure in Low and Middle-Income Countries: Perspectives and Lessons on Patterns, Injustices, Economics, and Politics

“…Globally, but in particular in Asia and Africa, e-waste recycling, in many cases performed inside home compounds, is an important source of exposure to lead and other chemicals [ 60 , 61 , 62 , 63 , 64 , 65 ]. In Bangladesh, an estimated 50,000 children are involved in e-waste recycling [ 66 ].…”