RESUMO
BACKGROUND: There remains a dearth of cross-city comparisons on the impact of climate change through extreme temperature and precipitation events on road safety. We examined trends in traffic fatalities, injuries and property damage associated with high temperatures and heavy rains in Boston (USA) and Santo Domingo (Dominican Republic). METHODS: Official publicly available data on daily traffic outcomes and weather conditions during the warm season (May to September) were used for Boston (2002-2015) and Santo Domingo (2013-2017). Daily maximum temperatures and mean precipitations for each city were considered for classifying hot days, warm days, and warm nights, and wet, very wet, and extremely wet days. Time-series analyses were used to assess the relationship between temperature and precipitation and daily traffic outcomes, using a quasi-Poisson regression. RESULTS: In Santo Domingo, the presence of a warm night increased traffic fatalities with a rate ratio (RR) of 1.31 (95% CI [confidence interval]: 1.00,1.71). In Boston, precipitation factors (particularly, extremely wet days) were associated with increments in traffic injuries (RR 1.25, 95% CI: 1.18, 1.32) and property damages (RR 1.42, 95% CI: 1.33, 1.51). CONCLUSION: During the warm season, mixed associations between weather conditions and traffic outcomes were found across Santo Domingo and Boston. In Boston, increases in heavy precipitation events were associated with higher traffic injuries and property damage. As climate change-related heavy precipitation events are projected to increase in the USA, the associations found in this study should be of interest for road safety planning in a rapidly changing environment.
RESUMO
BACKGROUND: In April 2016, Chile enacted the Law 20,900, which restricted electoral publicity on public roads. It established two important regulations: first, candidates were allowed, 30 days before any election, to publicize their campaigns in specific street locations. Second, roadside publicity must follow strict size standards to avoid visual contamination. This article examines the impact of this regulation in reducing road traffic crashes. METHODS: We obtained a number of traffic injuries and fatalities per population from public records. A time-series difference-in-difference study, using generalized linear models with an interaction between time-period and intervention, compared a municipal election period before the introduction of Law 20,900 (2012) to the first municipal election affected by the law (2016). We adjusted for precipitation and temperature, and applied models to three cities: Santiago, Gran-Valparaíso, and Concepción. We assessed the overall impact of the intervention using random effects meta-analyses. RESULTS: The law was associated with a decrease of 0.01 (95% confidence interval [CI]: -0.02, -0.00) in Santiago, a decrease of 0.01 (95% CI: -0.03, -0.00) in Valparaíso and an increase of 0.09 (95% CI: 0.06, 0.13) in Concepción, in all daily injuries and fatalities per 100,000 population. After 40 days of its implementation, the intervention was associated with a mild absolute reduction of 34 (95% reduction interval: -270, 67) traffic injuries and fatalities. CONCLUSIONS: This study estimates that the regulation of public road publicity had an overall mild effect on reducing traffic injuries and fatalities in three large cities in Chile.
Assuntos
Acidentes de Trânsito , Jurisprudência , Política , Ferimentos e Lesões , Acidentes de Trânsito/prevenção & controle , Acidentes de Trânsito/estatística & dados numéricos , Chile/epidemiologia , Cidades/epidemiologia , Humanos , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/prevenção & controleRESUMO
Air pollution standards and control strategies are based on ambient measurements. For many outdoor air pollutants, individuals are closer to their sources (especially traffic) and there are important indoor sources influencing the relationship between ambient and personal exposures. This paper examines the relationship between volatile organic compounds (VOCs) measured at central site monitoring stations and personal exposures in the Mexico City Metropolitan Area. Over a 1-year period, personal exposures to 34 VOCs were measured for 90 volunteers from 30 families living close to one of five central monitoring stations. Simultaneous 24-h indoor, outdoor and central site measurements were also taken. Dual packed thermal desorption tubes and C(18) DNPH-coated cartridges were used for sampling VOCs and these were analyzed by GC/MS and HPLC, respectively. A factor analysis of the personal exposure data aided in grouping compounds by the most likely source type: vehicular (BTEX, styrene and 1,3-butadiene), secondary formed or photochemical (most aldehydes), building materials and consumer products (formaldehyde and benzaldehyde), cleaning solvents (tetrachloroethene and 1,1,1-trichloroethane), volatilization from water (chloroform and trichloroethene) and deodorizers (1,4-dichlorobenzene). Mean ambient, indoor and personal concentrations were 7/7/14 microg/m(3) for benzene, 1/3/3 for 1,3-butadiene, 6/20/20 for formaldehyde and 3/9/50 for 1,4-dichlorobenzene. Geometric mean (GM) ambient concentrations of trichloroethene and carbon tetrachloride were similar to GM personal exposures. While outdoor and indoor home GM concentrations for most vehicular related compounds (benzene, MTBE, xylenes and styrene) were comparable, the GM personal exposures were twice as high. Indoor concentrations of 1,3-butadiene, 1,1,1-trichloroethane, tetrachloroethane, chloroform, formaldehyde, valeraldehyde, propionaldehyde and n-butyraldehyde were comparable to personal exposures. For certain compounds, such as chloroform, aldehydes, toluene, 1,3-butadiene and 1,4-dichlorobenzene, GM personal exposures were more than two times greater than GM ambient measurements.