Characterization and health risk assessment of VOCs in occupational environments in Buenos Aires, Argentina

Background Breath volatile organic compounds (VOCs) may be useful for asthma diagnosis and phenotyping, identifying patients who could benefit from personalised therapeutic strategies The authors aimed to identify specific patterns of breath VOCs in patients with asthma and in clinically relevant disease phenotypes Methods Breath samples were analysed by gas chromatography–mass spectrometry The Asthma Control Questionnaire was completed, together with lung function and induced sputum cell counts Breath data were reduced to principal components, and these principal components were used in multiple logistic regression to identify discriminatory models for diagnosis, sputum inflammatory cell profile and asthma control Results The authors recruited 35 patients with asthma and 23 matched controls A model derived from 15 VOCs classified patients with asthma with an accuracy of 86%, and positive and negative predictive values of 085 and 089, respectively Models also classified patients with asthma based on the following phenotypes: sputum (obtained in 18 patients with asthma) eosinophilia ≥2% area under the receiver operating characteristics (AUROC) curve 098, neutrophilia ≥40% AUROC 090 and uncontrolled asthma (Asthma Control Questionnaire ≥1) AUROC 096 Conclusions Detection of characteristic breath VOC profiles could classify patients with asthma versus controls, and clinically relevant disease phenotypes based on sputum inflammatory profile and asthma control Prospective validation of these models may lead to clinical application of non-invasive breath profiling in asthma

https://thorax.bmj.com/content/thoraxjnl/66/9/804.full.pdf

Non-invasive phenotyping using exhaled volatile organic compounds in asthma

Heavy metals in PM2.5 and in blood, and children's respiratory symptoms and asthma from an e-waste recycling area

Background: Toxic volatile organic compounds (VOC), like benzene, toluene, ethylbenzene and xylenes (BTEX), are atmospheric pollutants representing a threat to human health. They are released into the environment from mobile sources in urban settings, but newly polluted areas are gaining importance in countries where accelerated industrialization is taking place in suburban or rural settings. Methods: The review includes studies done in Mexico and Latin-America and countries considered to have emerging economies and are compared with similar studies in developed countries. Data about environmental VOC levels and exposure of children have been included. Also, information about health effects was reviewed. Articles were searched in PubMed and Scopus, and information was also obtained from the United States Environmental Protection Agency (EPA), the EPAs Integrated Risk Information System (IRIS-EPA) and state reports on air quality of Mexican cities. Results: VOC or BTEX levels reported in industrial and suburban areas were found to be higher due to the burning of fossil fuels and waste emission; whereas, in big cities, VOC emissions were mainly due to mobile sources. Even though TEX levels were under reference values, benzene was found at levels several times over this value in cities and even higher in industrial zones. Elevated VOC emissions were also reported in cities with industrial development in their peripheral rural areas. Public health relevance: Industrial activities have changed the way of life of small towns, which previously had no concern about environmental pollution and chemicals. No air monitoring is done in these places where toxic chemicals are released into rivers and the atmosphere. This work demonstrates the need for environmental monitors to protect human life in suburban and rural areas where industrial growth occurs without planning and ecological or health protection, compromising the health of new generations beginning in fetal development.

Volatile Organic Compounds in Air: Sources, Distribution, Exposure and Associated Illnesses in Children.

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.

https://www.jacionline.org/article/S0091-6749(08)01879-4/pdf

Increased asthma and respiratory symptoms in children exposed to petrochemical pollution

Background Measuring lung function, including bronchodilator response (BDR), is an integral part of asthma management in older children. While spirometry is possible in preschool-aged children, the question remains whether measuring BDR aids in asthma diagnosis in this age group.

Methods 431 healthy children and 289 children with asthma, aged 3–5 years, were recruited from kindergartens and the pulmonology clinic in Trelew, Argentina. Spirometry was performed at visit 1 and repeated after 15 min, with children randomised to placebo or salbutamol (400 µg). Spirometry was again performed within 8 weeks at visit 2. Within-session repeatability from visit 1 and between-session reproducibility were calculated using baseline spirometry. The within-session repeatability and receiver operating characteristic curve analyses were used to determine the optimal threshold values for BDR for spirometry outcome variables measured at the first visit, and sensitivity, specificity and diagnostic accuracy were determined.

Results As a group, children with asthma had lower lung function (FVC 1.11±0.12 L vs 1.01±0.15 L; FEV0.75 1.01±0.10 L vs 0.91±0.15 L) and a greater BDR (FEV0.75 group difference 8.6 (95% CI −5.0 to 14.3)%) than healthy children. BDR was best defined by change in FEV0.75; an increase of 11% showed the best balance between sensitivity (51%), specificity (88%), positive predictive value (47%) and negative predictive value (89%) for discriminating healthy from preschool-aged children with asthma.

Conclusions A negative BDR in a child suspected of having asthma makes a diagnosis of asthma less likely.

https://thorax.bmj.com/content/thoraxjnl/72/4/367.full.pdf

Assessing bronchodilator response in preschool children using spirometry

Recognition of asthma in community-based surveys can be problematic. We sought to develop and validate questionnaires that could identify elementary school-aged children likely to have asthma or who had poorly-controlled asthma. Questionnaires for parents (PQ) and students (SQ) to complete were developed using guidance on question wording from a focus group consisting of children with asthma and their parents. The gold standard for this study was a pulmonologist determination of asthma and this was used to calculate sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for each question and for combinations of questions. Questionnaires were distributed to 830 children attending elementary schools in Trelew, Argentina and 96% were returned. Test–retest reliability was determined in 221 randomly selected parents and children and very good levels of agreement were seen for individual questions. Asthma was diagnosed in 92 students. Overall, the PQ was able to detect asthma better than the SQ. Optimal diagnostic ability came by combining questions from the PQ and SQ. Not surprisingly, these questionnaires had a better NPV than PPV and can be used to determine which children require further evaluation.

Validation of a school-based written questionnaire for asthma case identification in Argentina

Background and objectiveWe recently developed and validated a screening questionnaire for determining which school-aged children may need further investigation to diagnose and manage asthma. In the present study we sought to extend this to pre-school aged children.

Validation of a questionnaire for asthma case identification in pre-schools in Latin America

AIM The Global Lung Function Initiative (GLI) has produced spirometry reference equations for use in different ethnic groups. Previous reports have shown that the GLI equations do not adequately describe lung function in all populations and that adopting the new equations into clinical practice can increase the number of patients considered to have abnormal lung function. Therefore, before adopting these equations into local practice it is necessary to establish how well the equations represent the local population. The present study was conducted to determine how well the GLI spirometry reference equations represented the young children in Argentina, a population not included in the GLI dataset. METHODS Spirometry was measured in 2072 healthy children (50.9% males) aged 3.0-12.4 years (mean 6.64 ± SD 1.39), with a height range of 93.0-158.5 cm and weight range from 13.1 to 54.7 kg. We used the GLI "Caucasian" and "other/mixed" race equations to create Z-scores. RESULTS The Z-scores predicted by the Caucasian GLI equations did not differ from zero and fitted the data well. Z-scores calculated using "other/mixed race" fit less well. Using the GLI definition of low lung function (Z-score <1.65) 6.8% of our healthy population had abnormal FVC, 4.9% had abnormal FEV1, 5.9 % had abnormal FEV0.75, and 3.9% had abnormal FEF25-75 when using the "Caucasian" GLI equation. This compares well with the expected 5% below the lower limit of normal. CONCLUSION We recommend the use of the GLI-2012 Caucasian equations for spirometry undertaken in Argentinian children.

Luciano Enrique Busi

Papers

Increased asthma and respiratory symptoms in children exposed to petrochemical pollution

Assessing bronchodilator response in preschool children using spirometry

Validation of a school-based written questionnaire for asthma case identification in Argentina

Validation of a questionnaire for asthma case identification in pre-schools in Latin America

Validation of the GLI‐2012 spirometry reference equations in Argentinian children