Formaldehyde exposure and asthma in children: a systematic review

Abstract

Formaldehyde exposure and asthma in children: a systematic review Exposição ao formol e asma em crianças: uma revisão sistemáticaResumo Apesar de múltiplos estudos publicados sobre a associação entre exposição ao formol e asma infantil, uma relação consistente ainda não foi identificada. Nós relacionamos os resultados de revisão de estudos publicados a fim de fornecer uma imagem mais compreensível desta relação. Após pesquisa, foram identificados sete estudos que proviam resultados quantitativos sobre a associação entre a exposição ao formol e a asma infantil. Estudos foram heterogêneos em relação à definição de asma. Para cada estudo, uma razão de chances (RC) e 95% de intervalo de confiança (IC) para asma foram abstraídos de resultados publicados ou calculados baseados nos dados fornecidos. Foram usados modelos de efeitos fixos e aleatórios para calcular RC agrupados e IC de 95%; medidas de heterogeneidade também foram calculadas. Um modelo de efeitos fixos produziu um a RC de 1.03 (IC de 95%, 1.02-1.04), e o modelo de efeitos aleatórios produziu uma RC de 1.17 (IC de 95%, 1.01-1.36), ambos refletindo um aumento de 10 μg/m3 de exposição ao formol. As estatís-ticas de Q and I2 indicaram uma quantidade moderada de heterogeneidade. Resultados indicam uma associação positiva entre exposição ao formol e asma infantil. Devido à natureza de cruzamento de dados destes estudos por baixo desta meta-análise, um estudo de prospectiva epidemiológica mais aprofundada é necessário. Palavras-chave Asma, Crianças, Epidemiologia, Formol Abstract Despite multiple published studies regarding the association between formaldehyde exposure and childhood asthma, a consistent association has not been identified. Here we report the results of a systematic review of published literature in order to provide a more comprehensive picture of this relationship. After a literature search, we identified seven studies providing quantitative results regarding the association between formaldehyde exposure and asthma in children. Studies were heterogeneous with respect to the definition of asthma. For each study, an odds ratio (OR) and 95% confidence interval (CI) for asthma were abstracted from published results or calculated based on the data provided. We used fixed-and random-effects models to calculate pooled ORs and 95% CIs; measures of heterogeneity were also calculated. A fixed-effects model produced an OR of 1.03 (95% CI, 1.02-1.04), and random effects model produced an OR of 1.17 (95% CI, 1.01-1.36), both reflecting an increase of 10 μg/m3 of formaldehyde. Both the Q and I2 statistics indicated a moderate amount of heterogeneity. Results indicate a positive association between formaldehyde exposure and childhood asthma. Given the largely cross-sectional nature of the studies underlying this meta-analysis, further well-designed prospective epidemiologic studies are needed.

Indoor Air Contaminants and Their Impact on Respiratory Pathologies

“…They also promote sensitization mechanisms by means of a synergist effect, thus causing an allergic reaction with a smaller quantity of allergen, as well as the reduction in s-nitrosoglutathione, which is an endogenous bronchodilator. 41,42 Radon decays into solid radioactive elements, like polonium, which release alpha particles, a form of high-energy radiation that can deteriorate human DNA. The energy of these particles is regardless of radon concentrations, so that even at low concentrations it can be harmful, and therefore the toxicity of radon does not require a threshold level.…”

“…A recent systematic review seems to confirm an increase in the prevalence of asthma in children of 3% for every 10 g/m 3 of increase in formaldehyde levels. 42 A case-control study with children demonstrated that the exposure to other VOC like acetaldehyde or toluene significantly increases the prevalence of asthma. The effect seems different depending on whether the residence is urban or rural or on the season of the year.…”

Formation of aldehydes and carboxylic acids in ozonated surface water and wastewater: A clear relationship with fluorescence changes

“…These ACA compounds and other groups of low-molecular-weight disinfection by-products (DBPs, <300 Da) formed upon the oxidation of natural organic matter (NOM) or effluent organic matter (EfOM) that is present in drinking water and wastewater, respectively may be significant for several reasons. Some aldehydes (e.g., formaldehyde, acetaldehyde, glyoxal and methylglyoxal) are toxic and had been classified as known carcinogens or suspected carcinogens (Richardson et al, 2007;McGwin et al, 2009). They may also be responsible for the undesirable odor in the treated waters because of their very low odor detection thresholds, e.g., 4.0 lg L À1 for acetaldehyde (Dą browska and Nawrocki, 2013).…”

Source emission and model evaluation of formaldehyde from composite and solid wood furniture in a full-scale chamber

“…Acute and chronic inhalation exposures to formaldehyde in humans, particularly children, can result in respiratory symptoms and irritations of the eyes, nose, and throat (McGwin, Jr. et al, 2010). The U. S.…”