Formaldehído en viviendas urbanas en Salvador, Bahía-Brasil

Abstract

Formaldehyde is a common contaminant in indoor environments. The objective of the present study was to identify formaldehyde concentrations in urban households and to investigate a possible association between the formaldehyde concentration and potential indoor sources. This is a cross-sectional study nested within SCAALA, a large longitudinal study conducted to investigate factors associated with asthma and allergy in schoolchildren in Salvador. The homes of 1168 children from 4 to 13 years old were visited between February 2007 and July 2008 to collect data on the household characteristics. Fluorometric determination of gaseous formaldehyde was conducted using the Fluoral-P reagent. Logistic regression with calculation of odds ratios and their respective 95 [%] confidence intervals (95 [%] CI), was used to evaluate ventilation, sources of formaldehyde, and exposure to cigarette smoke according to formaldehyde concentrations. Formaldehyde concentrations were low (a mean of 0.80 µ/m3). A higher number of potential sources of formaldehyde emission (OR: 1.30; 95 [%] CI: 1.03-1.65) and better ventilation (OR: 1.35; 95 [%] CI: 1.07-1.70) were factors associated with higher concentrations. Formaldehyde concentrations were lower in homes where there were smokers, (OR: 0.69; 95 [%] CI: 0.52-0.90). Indoor formaldehyde concentrations in the homes evaluated in Salvador were below the maximum allowable concentrations determined nationally and internationally. The characteristics of the homes played a role in formaldehyde levels. The environmental sampling method used to determine formaldehyde concentrations was sufficiently accurate.