Exposure of children to polycyclic aromatic hydrocarbons in Mexico: assessment of multiple sources

Biological monitoring of polycyclic aromatic hydrocarbons (PAHs) has expanded rapidly since urinary 1-hydroxypyrene (1-OHP) was suggested as a biological index for pyrene. Taking into account that pyrene is often present in PAHs mixtures, 1-OHP has also been considered an indirect indicator of exposure to these mixtures. Sources of PAHs in developing countries are numerous; however, exposure of children to PAHs has not been studied in detail. Therefore, the aim of this study was to assess exposure of children to PAHs in different scenarios: (a) children living next to highways with heavy traffic; (b) sanitary landfill; (c) brick kiln communities and (d) children exposed to biomass combustion. A total of 258 children (aged 3-13) participated in the study. The analyses were performed by HPLC with fluorescence detector. Urinary 1-OHP concentrations were then adjusted by urinary creatinine. The highest levels of 1-OHP in this study were found in children exposed to biomass combustion (mean value 3.25 mu mol/mol creatinine), but exposure was also detected in children living in communities with brick kiln industry (mean 0.35 mu mol/mol creatinine), or in a community next to a sanitary landfill (with waste combustion) (0.30 mu mol/mol creatinine) and in children exposed to traffic (mean value 0.2 mu mol/mol creatinine and 0.08 mu mol/mol creatinine). Considering our results and taking into account that millions of children in Mexico are living in scenarios similar to those studied in this work, the assessment of health effects in children exposed to PAHs is urgently needed; furthermore, PAHs have to be declared contaminants of concern at a national level.