Exposure to Mixtures of Pollutants in Mexican Children from Marginalized Urban Areas

Abstract

Background: Exposure to contaminant mixtures in developing countries is an important public health issue. Children are identified as the most susceptible group to adverse health effects due to the exposure. Objective: The aim of this study was to conduct a screening for mixture pollutants in Mexican children in urban marginalized communities. Methods: We analyzed children (aged 6-12 years old) who resided in four urban marginalized communities in San Luis Potosi, Mexico: i) Bellas Lomas (BEL), a site with vehicular traffic; ii) Tercera Chica (TC), a site with brick kilns; Iii) Rincon de San Jose (SJR), a site with a hazardous waste landfill; and (iv) Morales (MOR) a metallurgical zone with copper-arsenic and electrolytic zinc smelters. Polycyclic Aromatic Hydrocarbons (1-hydroxypyrene (1-OHP)), benzene (trans, trans-muconic acid (t,t-MA), manganese, arsenic and fluoride were quantified in urine and lead in blood samples. Findings: Our results indicate that median exposures to manganese were 4.4, 5.2, 5.8 and 6.3 µg/L for BEL, TC, SJR and MOR, respectively. For BEL, fluoride was present at a higher concentration with 2.3 mg/L followed by MOR, TC and SJR with 1.7, 1.5 and 1.2 mg/L respectively. The highest concentrations of arsenic that were found were 11 µg/L in MOR and lead concentration was reported between 4.2 and 6.8 µg/dL, in BEL, TC and MOR. 1-OHP and t,t-MA were higher in TC (0.23 µmol/mol creatinine (cr), 429.7 µg/g cr, respectively) followed by SJR (0.09 µmol/mol cr, 427.4 µg/g cr), MOR (0.03 µmol/mol cr, 258.6 µg/g cr) and BEL (0.06 µmol/mol cr, 220.6 µg/g cr).

Evaluation of Benzene Exposure and Early Biomarkers of Kidney Damage in Children Exposed to Solvents Due to Precarious Work in Ticul, Yucatán, México

“…On the other hand, it has been reported that 70–80% of a child population living in a petrochemical area of the state of Veracruz, Mexico, has lower levels of tt-MA (0.36–0.38 mg/g Creatinine) than the levels found in this study [36]. Other studies of children from marginalized urban areas also showed lower median values of tt-MA (0.220–0.429 mg/g Creatinine [37]. Clearly, these differences are mainly due to the exposure scenario.…”

Analysis of urinary metabolites of polycyclic aromatic hydrocarbons in precarious workers of highly exposed occupational scenarios in Mexico

“…(iii) Brickmakers (TER) are located in the brick zone “Las terceras” in San Luis Potosi, Mexico (22° 12′ 04″ N, 100° 51′ 26″ W); the municipality has a population of 824,229 inhabitants; in this scenario, there are more than 120 brick kilns, which use wood tires, waste, used oil, and plastics as fuel. (Flores-Ramirez et al 2018 ) (Fig. 1c ).…”

“…It is evident that workers are a vulnerable group, requiring special attention to mitigation measurements; however, some groups of workers are especially vulnerable; those so-called precarious works, characterized by abuse of their labor rights (low salaries, without access to social security, health services, lack of training, null protection, among many other factors) (Julià et al 2017 , Kachi et al 2014 , Medina-Gómez and López-Arellano 2019 ) and which also present health risks due to high exposure to pollutants. The above, in scenarios with high degrees of marginalization, where they generally perform their work activities within the household, exposing the worker and in consequence their families (Flores-Ramirez et al 2018 , Pérez-Herrera et al 2019 ). Therefore, the objective of this research was to evaluate the mixtures of hydroxylated PAHs in precarious workers of four activities with high toxicity in Mexico.…”

Heavy Metal Contamination (Cu, Pb, Zn, Fe, and Mn) in Urban Dust and its Possible Ecological and Human Health Risk in Mexican Cities

“…In Mérida and Ensenada the color of urban dust has proved to be an indicator of heavy metal pollution, dark colors are more polluted than light ones (Cortés et al, 2015;Aguilar et al, 2021). In San Luis Potosí, the highest concentrations of heavy metals in urban dust have been related to the metallurgical complex and the industrial park (Aguilera et al, 2019); and heavy metals in soils could also be an important pathway of exposure (Perez-Vazquez et al, 2015;Pérez-Vázquez et al, 2015), indeed metal concentrations have been identified in children (Flores-Ramírez et al, 2018). Mexico City has been identified as polluted by heavy metals in urban dust (Delgado et al, 2019), and heavy metal concentrations have been measured in mothers and children (Lewis et al, 2018).…”