Andrés Porta

Increased asthma and respiratory symptoms in children exposed to petrochemical pollution.

BACKGROUND Epidemiologic studies show statistical associations between levels of air pollutants and respiratory outcomes. OBJECTIVE We sought to determine the effects of exposure to petrochemical pollution on the respiratory health of children. METHODS Children aged 6 to 12 years living close to the petrochemical plants in La Plata, Argentina (n = 282), were compared with those living in a region with exposure to heavy traffic (n = 270) or in 2 relatively nonpolluted areas (n = 639). Parents answered a validated questionnaire providing health and demographic data. A random sample (n = 181) had lung function measured. Particulate matter and outdoor and indoor volatile organic compound levels were measured during 4-week study periods and reported as overall means for each study area. RESULTS Children living near the petrochemical plant had more asthma (24.8% vs 10.1% to 11.5%), more asthma exacerbations (6.7 vs 2.9-3.6 per year), more respiratory symptoms (current wheeze, dyspnea, nocturnal cough, and rhinitis), and lower lung function (>13% decrease in FEV(1) percent predicted) than those living in other regions. Length of residence in the area was a significant risk factor, but age, sex, body mass index, proximity to busy roads and other nonpetrochemical industries, length of breast-feeding, and socioeconomic and demographic characteristics of children or their families were not. CONCLUSION Exposure to particulate matter and volatile organic compounds arising from petrochemical plants but not from high traffic density was associated ith worse respiratory health in children.

Indoor-outdoor distribution and risk assessment of volatile organic compounds in the atmosphere of industrial and urban areas.

Volatile organic compounds (VOCs), which play an important part indoors and outdoors, comprise differing compound groups such as n‐alkanes, cycloalkanes, aromatic and chlorinated hydrocarbons and terpenes. In the current study, samples were analyzed from indoor (schools and houses, n = 92) and outdoor (n = 33) air in urban, industrial, semirural and residential areas from the region of La Plata (Argentine) to consider VOC exposure in different types of environments. VOCs were sampled for 1 month during winter for 3 years, with passive 3M monitors. Samples were extracted with CS2 and analyzed by GC/MS detectors. The results show significant differences in concentration and distribution between indoor and outdoor samples, depending on the study area. Most VOCs predominantly originated indoors in urban, semirural and residential areas, whereas an important outdoor influence in the industrial area was observed. In all areas alkanes and aromatic compounds dominated, even though a different chemical distribution was seen. Traffic burden was determined as the major source of outdoor VOC with a benzene/toluene ratio close to 0.5. Indoors, C9–C11 alkanes, toluene and xylenes dominated, caused by human activities. In contrast, in the industrial area higher concentrations of hexane, heptane and benzene occurred outdoors and affected the indoor air significantly. The lifetime cancer risk (LCR) associated to the benzene exposure was calculated for children from the different study areas. For all groups the study showed a LCR value greater than 1 × 10−6 related to the benzene exposure indoors as well outdoors. A value two magnitudes higher was detected indoors in the industrial area, what demonstrates the high risk for children living in this area of La Plata.

Catalytic removal of a mixture of volatile organic compounds present in indoor air at various work sites over Pt, MnOx and Pt/MnOx supported monoliths

The elimination of volatile organic compounds (VOCs) was investigated placing a novel catalytic system in the chimney venting of a commercial air extractor, using Pt, Mn and Pt/Mn catalysts supported on ceramic monoliths. The VOCs oxidized were chloroform (CHCl3), methyl ethyl ketone (MEK), toluene and xylene, alone, in a binary mixture and in a mixture of all of them. The conversion of VOCs is in general similar, regardless of whether they are in a mixture or alone. Pt/Mn monoliths exhibited the highest destruction activity for the abatement of VOCs alone and in mixtures, due to a synergetic effect between platinum and manganese. The results show that these catalytic systems can be coupled satisfactorily in the venting of the air extraction equipment still working at high flow rates.

A method for computing the damage level due to the exposure to an airborne chemical with a time-varying concentration.

The calculation of damage level due to the exposure to a toxic cloud is usually not included in most popular software, or it is included using techniques that do not take into account the variation in concentration over a period of time. In this work, a method is introduced for calculating the temporal evolution of the potential damage level and to obtain a more precise and descriptive estimation of this level. The proposed goal is: to estimate the maximum and minimum damage level experienced by a population due to the exposure to an airborne chemical with a time-varying concentration; to be able to assess the damage level experienced in a progressive way, as the exposure to the airborne chemical occurs. The method relies on transformations of time-concentration pairs on a continuum of damage level curves based on the available guideline levels, obtaining maximum and minimum approximations of the expected damage level for any exposure duration. Consequently, applying this method to transport model output data and demographic information, damage evolution in relation to time and space can be predicted, as well as its effect on the local population, which enables the determination of threat zones. The comparison between the proposed method and the current (Spanish and ALOHA) ones showed that the former can offer a more precise estimation and a more descriptive approach of the potential damage level. This method can be used by atmospheric dispersion models to compute damage level and graphically display the regions exposed to each guideline level on area maps.

Characterization and cancer risk assessment of VOCs in home and school environments in gran La Plata, Argentina

Three areas are highlighted in Gran La Plata, Argentina: industrial, urban, and residential. In this work, the levels of volatile organic compounds (VOCs) in indoor air of homes and schools in those areas were analyzed, through the use of passive monitors. The study period is between 2007 and 2010. Higher levels of VOCs were found in homes and schools in the industrial zone, higher than the levels corresponding to urban and residential. Taking into account the relationship between indoor and outdoor levels of VOCs, they have ratios (I/O) between 1.5 and 10 are evidenced contributions of emission sources of VOCs both indoor and outdoor. Complementarily, we estimated the life time cancer risk (LCR) for benzene, styrene, trichloroethylene, and tetrachloroethylene in children who spend their time mostly in such indoor environments. The results show high LCR values for benzene, which exceed acceptable values for the US EPA.

Gaps between calcium recommendations to prevent pre-eclampsia and current intakes in one hospital in Argentina

BackgroundHypertensive disorders are a major cause of maternal mortality. In Latin America and the Caribbean, pre-eclampsia accounts for approximately one in every four maternal deaths. The World Health Organization recommends calcium supplementation during pregnancy for the prevention and treatment of pre-eclampsia and eclampsia in locations where dietary calcium intake is low. Calcium intake in Argentina is reported to be below WHO recommended levels; however, calcium intake from supplements and water has not been fully evaluated. The objective of this study was to evaluate calcium intake from supplements and water in a group of pregnant women.MethodsThis cross-sectional study was conducted at a maternity hospital in the city of Buenos Aires, Argentina. Questionnaires were verbally administered to women attending a routine antenatal care visit. Participants were 18 years of age or older and in their third trimester of pregnancy. Participants were first interviewed to evaluate nutritional supplement consumption and a subgroup was invited to undergo a 24-hour dietary recall.Results137 women meeting inclusion criteria consented to participate. The average participant age was 27 years (SD ± 5.9), and all resided in an urban setting. None of the subjects took calcium supplements specifically, although 24 (17%) recalled taking supplements or antacids which contributed to their calcium intake. Mean calcium intake was 663mg SD ±389 for those women completing the 24-hour dietary recall,. This value increased to 706 mg SD ±387 upon considering water intake and measuring chemical composition of water from the areas where women lived at the time of the interview and was further increased to 719 mg (SD ±392) when calcium from supplements was taken into consideration.ConclusionsNone of the subjects were consuming calcium supplements. Taking into account the low calcium intake in this population, diverse strategies would be required to comply with recommendations.