Morbidity and mortality of people who live close to municipal waste landfills: a multisite cohort study.

BACKGROUND: The evidence on the health effects related to residing close to landfills is controversial. Nine landfills for municipal waste have been operating in the Lazio region (Central Italy) for several decades. We evaluated the potential health effects associated with contamination from landfills using the estimated concentration of hydrogen sulphide (H2S) as exposure. METHODS: A cohort of residents within 5 km of landfills was enrolled (subjects resident on 1 January 1996 and those who subsequently moved into the areas until 2008) and followed for mortality and hospitalizations until 31 December 2012. Assessment of exposure to the landfill (H2S as a tracer) was performed for each subject at enrolment, using a Lagrangian dispersion model. Information on several confounders was available (gender, age, socioeconomic position, outdoor PM10 concentration, and distance from busy roads and industries). Cox regression analysis was performed [Hazard Ratios (HRs), 95% confidence intervals (CIs)]. RESULTS: The cohort included 242 409 individuals. H2S exposure was associated with mortality from lung cancer and respiratory diseases (e.g. HR for increment of 1 ng/m(3) H2S: 1.10, 95% CI 1.02-1.19; HR 1.09, 95% CI 1.00-1.19, respectively). There were also associations between H2S and hospitalization for respiratory diseases (HR = 1.02, 95% CI 1.00-1.03), especially acute respiratory infections among children (0-14 years) (HR = 1.06, 95% CI 1.02-1.11). CONCLUSIONS: Exposure to H2S, a tracer of airborne contamination from landfills, was associated with lung cancer mortality as well as with mortality and morbidity for respiratory diseases. The link with respiratory disease is plausible and coherent with previous studies, whereas the association with lung cancer deserves confirmation.

[Inverse probability weighting (IPW) for evaluating and "correcting" selection bias]. / L'uso dell'Inverse probability weighting (IPW) nella valutazione e "correzione" del selection bias.

INTRODUCTION: the Inverse probability weighting (IPW) is a methodology developed to account for missingness and selection bias caused by non-randomselection of observations, or non-random lack of some information in a subgroup of the population. OBJECTIVES: to provide an overview of IPW methodology and an application in a cohort study of the association between exposure to traffic air pollution (nitrogen dioxide, NO2) and 7-year children IQ. METHOD: this methodology allows to correct the analysis by weighting the observations with the probability of being selected. The IPW is based on the assumption that individual information that can predict the probability of inclusion (non-missingness) are available for the entire study population, so that, after taking account of them, we can make inferences about the entire target population starting from the nonmissing observations alone.The procedure for the calculation is the following: firstly, we consider the entire population at study and calculate the probability of non-missing information using a logistic regression model, where the response is the nonmissingness and the covariates are its possible predictors.The weight of each subject is given by the inverse of the predicted probability. Then the analysis is performed only on the non-missing observations using a weighted model. CONCLUSIONS: IPW is a technique that allows to embed the selection process in the analysis of the estimates, but its effectiveness in "correcting" the selection bias depends on the availability of enough information, for the entire population, to predict the non-missingness probability. In the example proposed, the IPW application showed that the effect of exposure to NO2 on the area of verbal intelligence quotient of children is stronger than the effect showed from the analysis performed without regard to the selection processes.

[Morbidity in a population living close to urban waste incinerator plants in Lazio Region (Central Italy): a retrospective cohort study using a before-after design]. / Stato di salute della popolazione residente nei pressi dei termovalorizzatori del Lazio: uno studio di coorte retrospettivo con approccio pre-post.

BACKGROUND: the body of evidence on health effects of residential exposure to urban waste incinerators suggests association with reproductive outcomes and some cancers, but the overall evidence is still limited. OBJECTIVES: we evaluated the impact of two incinerators on hospital admissions for respiratory and cardiovascular diseases in a cohort of people living nearby two incineration plants in Lazio Region (Central Italy) using a before-and-after design. METHODS: the study area was defined as the 7-km radius around the incinerators. People who were resident in the area from 1996 to 2008 were enrolled in a retrospective longitudinal study. All addresses were geocoded. A Lagrangian dispersion model (SPRAY) for PM10 (ng/m³) was used for incinerators exposure assessment. Average annual concentration of background PM10 (µg/m³) was estimated on a regional basis by means of RAMS and FARM models. Both PM10 exposures were estimated at the residential address. All subjects were followed for hospital admissions in the period before (1996-2002) and after (2003-2008) the activation of the plants. The association between exposure to emissions from incinerators and hospitalizations in the two periods was estimated using the multivariate Cox model (for repeated events), adjusting for age, area-level socioeconomic status, distance from industries, traffic roads and highways. An interaction term between the period of follow-up (before or after the activation of the plants) and the exposure levels was used to test the effect of the incinerators. RESULTS: 47,192 subjects resident in the study area were enrolled. No clear association between pollution exposure from incinerators and cause-specific morbidity of residents in highest concentration areas was found when compared to the reference group. However, an effect of PM10 on respiratory diseases and chronic obstructive pulmonary disease was suggested. The effect was due to excesses of hospitalizations for the same causes among men living in highest exposure areas in respect to the reference group (hazard ratio - HR: 1.26; 95%CI 0.99-1.60, and HR: 1.86; 95%CI 1.04-3.33, respectively). There were associations between exposure to background pollution from other sources and hospitalizations for diseases of the circulatory system (HR: 1.08; 95%CI 1.03-1.13) and respiratory diseases (HR: 1.07; 95%CI 1.02-1.11) (for a unitary increment of PM10, µg/m³). CONCLUSIONS: living in areas with high PM10 levels due to incinerators was associated with increased morbidity levels for respiratory disorders among men. The study area is critical from an environmental point of view, hence an epidemiological surveillance is recommended.

[Health impact assessment of airport noise on people living nearby six Italian airports]. / Valutazione dell'impatto del rumore aeroportuale sulla salute della popolazione residente nelle vicinanze di sei aeroporti italiani.

BACKGROUND: aircraft noise has been associated with several health effects. Because of the great success of low-cost flights, small airports have been turned into international airports thus exposing nearby residents to an increase in noise levels and potential disturbances and health disorders. OBJECTIVE: to estimate the exposure levels and evaluate the health impact of aircraft noise on residents nearby six airports in Italy (Rome: Ciampino; Milan: Linate and Malpensa; Pisa; Turin; Venice) focusing on hypertension, acute myocardial infarction (AMI), annoyance and sleep disturbances. METHODS: residents in the local Municipalities considered at 31.12.2010 were included in the study and their addresses were geocoded. Aircraft noise exposure in 2011 was defined using the Integrated Noise Model linked to each participant's address. Lden (<55, 55-60, 61-65, 65-70 dB), Lnight, Leq (day and night) were calculated. Available exposure-response relationships were used to estimate the number of additional cases of hypertension, AMI, annoyance and sleep disturbances in the local population. RESULTS: 73,272 persons exposed to aircraft noise levels >55dB were considered: 55,915 (76.3%) were exposed to 55-60 dB; 16,562 (22.6%) to 60-65 dB; 795 (1.2%) to 65-70 dB. Exposure to aircraft noise levels above 55 dB was estimated to be responsible each year of 4,607 (95%CI 0-9,923) additional cases of hypertension; 3.4 (95%CI 0-10.7) cases of AMI; 9,789 (95%CI 6,895-11,962) cases of annoyance; 5,084 (95%CI 1,894-10,509) cases of sleep disturbances. CONCLUSIONS: a significant impact of airport noise on the health of residents nearby six Italian airports was estimated. Epidemiological evaluation and noise mitigation measures should be introduced to protect the health of residents.

[Residential cohort approach in industrial contaminated sites: the ERAS Lazio project]. / Lo studio di coorte di popolazione in aree a forte pressione ambientale: il programma ERAS Lazio.

The population-based cohort study is the best design for assessing the possible health effects resulting fromliving in contaminated sites. The ERAS (Epidemiology,Waste disposal, Environment and Health) Project was established to study the health of people living in close proximity to urban solid waste treatment (RU) plants in Lazio. It was conducted using an integrated approach, which consisted in studying mortality and hospital discharges of residential cohorts surrounding urban waste treatment plants. The level of exposure of each address was assigned using pollution dispersion models and studying the effects on mortality and hospital discharges. Further studies were conducted on residents of areas adjacent to waste disposal sites (includingMalagrotta in Rome), incinerators andmechanical biological treatment plants. The final version of the ERAS Report is available at www.eraslazio.it. The residential cohort approach and the combination of environmental and health-related information proved invaluable in the assessment of the health impact of solid waste treatment in Lazio.