Voluntary household smoking restrictions, and especially complete home smoking bans, can substantially reduce child ETS exposure [8-12]. Studies evaluating smoking restrictions have found that U.S. Hispanic households are as likely or more likely to ban smoking in the home and automobile than non-Hispanic White households, and significantly more likely to ban smoking than African American households [13,14]. Few studies have examined automobile smoking bans among racial/ethnic groups, though existing data suggest that the prevalence of car smoking bans among U.S. Hispanics (67%) is similar to Whites, but higher than among African Americans (55%) [13]. To date no studies have examined the prevalence and degree of voluntary smoking restrictions or child ETS exposure among U.S.-born and Mexico-born Hispanics.

Hispanics are heterogeneous with respect to social and cultural characteristics as well as various health outcomes including tobacco use [15,16]. Smoking prevalence is a strong predictor of smoking bans, and recent data indicate substantial heterogeneity in smoking prevalence rates among U.S. Hispanic subgroups, particularly between English- and Spanish-speaking Hispanic women [17]. These differences in smoking rates may also extend to differences in voluntary smoking restrictions among U.S. Hispanic subgroups.

Clinic appointment logs and sign-in sheets were used to systematically screen women who presented for clinic services. Eligible study participants included U.S.-born or Mexico-born Hispanic mothers of children aged 2 through 12 years. During screening, women were asked, "Which of the following best describes your ethnicity?". Response options were Mexican, Mexican American, Spanish New Mexican, Other Hispanic, and non-Hispanic. Women who responded 'Other Hispanic' were eligible if they were born in the United States or Mexico. A total of 357 eligible Hispanic mothers were identified. Of these, 81 declined to participate and an additional seven interviews could not be completed for other reasons, resulting in a final sample size of 269 (144 U.S.-born; 125 Mexico-born) mothers. The overall response rate was 75.4% (70% for Spanish speakers and 81% for English speakers).

Young children's ETS exposure occurs primarily in homes and automobiles [21]. The overall prevalence (86%) of home smoking bans observed in our sample of U.S.- and Mexico-born Hispanic mothers in Albuquerque, New Mexico is somewhat higher than findings from studies of California Hispanics (79.9%) [13]. Only a few studies have reported on automobile smoking bans. Our observed prevalence (81%) of complete smoking bans for the family automobile was also higher than rates reported by Norman et al. among Hispanics (67%) and African Americans (55%) in California, and more than double the 38% reported by Kegler and Malcoe among rural low-income families of Native American and White young children in Oklahoma [13,14]. The higher rate of smoking bans observed in our study may reflect the presence of children in all study homes, as well as the lower smoking prevalence among U.S. Hispanic women in general and Mexico-born women in particular [11,14,22-25]. However, despite the higher prevalence of home and automobile smoking bans observed in our study, substantial opportunity for improvement remains, especially among smoking and U.S.-born Hispanic mothers.

Previous studies have demonstrated that smokers are less likely to ban home and automobile smoking [11-13,23]. Our study confirms these findings in a clinic-based sample of Hispanic families with young children. We found that complete bans were present in 63% of smoking households, in contrast with 96% of nonsmoking households. Further, our multivariate analyses showed that U.S.-born mothers and homes with adult smoker(s) other than the mother had much greater odds of lacking complete home and automobile smoking bans. These latter findings suggest that interventions to increase smoke-free home environments for Hispanic children in the southwestern United States should focus on U.S.-born mothers in particular and utilize strategies that impact smoking practices of all household members [26].

An important tobacco control objective of Healthy People 2010 is to reduce the proportion of U.S. children who are regularly exposed to tobacco smoke in the home [27]. We found that 36% of Hispanic children in our sample lived with a smoker. Our analyses further showed that complete smoking bans were associated with seven to 10-fold lower odds of room or automobile ETS exposure among Hispanic children. Several randomized controlled trials have demonstrated the effectiveness of parent counselling and coaching for decreasing children's reported ETS exposure, but only one has shown significant decreases in objective ETS exposure measures greater than those observed among controls [26,28-30]. Notably, Hovell and colleagues showed that coaching is effective in reducing ETS exposure among Latino asthmatic children where the majority of mothers were nonsmokers and of Mexican descent [26]. However, no trials have investigated the effectiveness of interventions for reducing home ETS exposure among children of U.S.-born Hispanics. Our multivariate findings, which showed that Hispanic children of U.S.-born mothers (compared with Mexico-born mothers) had three-fold increased odds of room ETS exposure, indicate that future trials should design and test ETS interventions targeting U.S.-born Hispanics with young children.