Urinary 1-hydroxypyrene concentration from Mexican children living in the southeastern region in Mexico.

Biomass combustion indoors has been associated with generation of various pollutants, such as carbon monoxide, formaldehyde, respirable particles, toluene, benzene and polycyclic aromatic hydrocarbons (PAHs), among others. In this context, the aim of this study was to evaluate the urinary 1-hydroxypyrene (as a biomarker exposure to PAHs) levels in children living in three states in Mexico. We evaluated children living in communities that use biomass fuels to cook and to heat homes in the next states: Chiapas, Oaxaca and Quintana Roo. We found similar levels of 1-OHP in urine of children living in the three studied states, with mean levels of 3.5 ± 1.0; 4.5 ± 2.8 and 4.4 ± 2.5 µg/L (geometric mean ± standard deviation), respectively for Chiapas, Oaxaca and Quintana Roo. In conclusion, our data indicate high exposure levels to PAHs in children living in the states studied in this work.

Assessment of the levels of DDT and its metabolites in soil and dust samples from Chiapas, Mexico.

The aim of this study was to assess the levels of DDT and its metabolites in two environmental matrices (soil and dust) in five communities in Chiapas, Mexico. DDT and its metabolites were analyzed by gas chromatography/mass spectrometry. The soil levels of total DDT ranged from non detectable (

Assessment of DDT, DDE, and 1-hydroxypyrene levels in blood and urine samples in children from Chiapas Mexico.

PURPOSE: The aim of this study was assess co-exposure to DDT, DDE (main DDT metabolite), and PAHs (1-hydroxypyrene) in areas where biomass is used to cook and to heat homes and where DDT was used to combat malaria transmission. METHODS: During 2009, we analyzed a total of 190 blood and urine samples from children living in six communities in Mexico. Quantitative analyses of DDT and DDE were performed using gas chromatography coupled with mass spectrometry. Analyses of 1-hydroxypyrene were performed by HPLC using a fluorescence detector. RESULTS: In this work, we found high levels of DDT and its principal metabolite (DDE) in the blood of children living in four communities in Chiapas located in the southeastern region of Mexico (range,

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

PURPOSE: 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. METHODS: 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. RESULTS: The highest levels of 1-OHP in this study were found in children exposed to biomass combustion (mean value 3.25 micromol/mol creatinine), but exposure was also detected in children living in communities with brick kiln industry (mean 0.35 micromol/mol creatinine), or in a community next to a sanitary landfill (with waste combustion) (0.30 micromol/mol creatinine) and in children exposed to traffic (mean value 0.2 micromol/mol creatinine and 0.08 micromol/mol creatinine). CONCLUSIONS: 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.

Indoor air pollution in a Mexican indigenous community: evaluation of risk reduction program using biomarkers of exposure and effect.

Indoor air pollution can be an important risk factor for human health, considering that people spend more than 60% of their time indoors. Fifty percent of the world population and approximately 90% of the rural population in developing countries are using biomass as energy source. Latin America represents 12% of the global consumption of biomass; in Mexico, 27 million people use wood as an energy source. Therefore, in this study we evaluated a 3-stage risk reduction program. The stages were: 1) removal of indoor soot adhered to roofs and internal walls; 2) paving the dirt floors; and 3) introduction of a new wood stove with a metal chimney that expels smoke outdoors. The complete intervention program was applied. In 20 healthy subject residents from an indigenous community in San Luis Potosí, Mexico, we measured blood carboxyhemoglobin (% COHb), DNA damage (comet assay) in nucleated blood cells, and urinary 1-OHP levels before and after the program. Before intervention individuals had a geometric mean COHb level of 4.93% and 53% of the population presented levels above 2.5% considered a safe level. However, in all the studied individuals the levels of COHb were reduced to below 2.5% (mean level 1.0%) one month after the intervention. Moreover, when compared, DNA damage in people exposed before the intervention was higher (5.8+/-1.3 of Tail Moment) than when the program was introduced (2.8+/-0.9 of Tail Moment) (P>0.05) and a same trend was observed with urinary 1-OHP levels; 6.71+/-3.58 micromol/mol creatinine was the concentration before intervention; whereas, 4.80+/-3.29 micromol/mol creatinine was the one after the program. The results suggest that the intervention program offers an acceptable risk reduction to those families that use biomass for food cooking.