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International audience; OBJECTIVES: Waste incineration releases a mixture of chemicals with high embryotoxic potential, including heavy metals and dioxins/furans, into the atmosphere. In a previous ecological study we found an association between the risk of urinary tract birth defects and residence in the vicinity of municipal solid waste incinerators (MSWIs). The objective of the present study was to specifically test this association. METHODS: A population-based case-control study compared 304 infants with urinary tract birth defects diagnosed in the Rhône-Alpes region (2001-2003) with a random sample of 226 population controls frequency-matched for infant sex and year and district of birth. Exposure to dioxins in early pregnancy at the place of residence, used as a tracer of the mixture released by 21 active waste incinerators, was predicted with second-generation Gaussian modelling (ADMS3 software). Other industrial emissions of dioxins, population density and neighbourhood deprivation were also assessed. Individual risk factors including consumption of local food were obtained by interviews with 62% of the case and all control families. RESULTS: Risk was increased for mothers exposed to dioxins above the median at the beginning of pregnancy (OR 2.95, 95% CI 1.47 to 5.92 for dioxin deposits). When only interviewed cases were considered, risk estimates decreased mainly because the non-interviewed cases were more likely to live in exposed residential environments (OR 2.05, 95% CI 0.92 to 4.57). The results suggest that consumption of local food modifies this risk. CONCLUSIONS: This study confirms our previous observation of a link between the risk of urinary tract birth defects and exposure to MSWI emissions in early pregnancy and illustrates the effect of participation bias on risk estimates of environmental health impacts.

International audience; Since 1971, a municipal solid waste incinerator (MSWI) with high dioxin emission levels has been in operation in Besançon, France. We recently found a 2.3-fold risk of non-Hodgkin's lymphoma in the highest exposure zone using a Gaussian-type dispersion model as a proxy for dioxin exposure. However, the sources of PCDD/Fs in this area are a matter of controversy. The aim of this survey was therefore to examine the nature of the PCDD/F soil contamination in the surroundings of the MSWI to characterize whether more than one potential emission source could explain the presence of the PCDD/Fs. PCDD/F congener profiles were determined in 75 soil samples collected in the vicinity of the MSWI. They were compared according to the most environmentally impacted zones and to various spatial contrasts. PCDD/F concentrations ranged from 0.25 to 28.06 pg WHO-TEQ g(-1). Two different clustering algorithms identified the same main cluster (consisting of 73 samples). The remaining two soil samples composed either one, or two clusters. All clusters showed similar congener profiles. Moreover, no contrast was observed for congener distributions between complex and simple topographies, inside and outside the city boundary, the two most and the two least exposed areas, reflecting a common fingerprint. Congener profiles indicate that the area under influence of the MSWI is not subject to other point sources of PCDD/Fs. Since, the most polluting combustion chambers were recently shut down and replaced by a new one with up-to-date pollution control, slowly decreasing dioxin concentrations in the soils are to be expected.

International audience; Whether low environmental doses of dioxin affect the general population is the matter of intense debate and controversy. In a previous study, we found a 2.3-fold risk for non-Hodgkin lymphoma associated with residence in areas classified as highly exposed to dioxin emitted from a municipal solid waste incinerator (MSWI) (Besançon, France). The main limitation lay within the use of a first-generation Gaussian-type dispersion model as a proxy for dioxin exposure, since its accuracy had not been assessed before. The aim of this study was to validate this geographic-based exposure through PCDD/F measurements from soil samples. PCDD/F concentration, pH, organic carbon concentration, cation exchange capacity, and geomorphology and ecology features were assessed for 75 sampling points. In simple terrain (i.e. northeast of the MSWI), a significant association was highlighted between modeled dioxin ground-level air concentrations and log-transformed measured dioxin soil concentrations with a strong gradient across exposure categories. Conversely, in a complex topography situation (i.e. southwest of the MSWI), the model overpredicted ground-level air concentrations, particularly in the high exposure zone. First-generation modeling provided a reliable proxy for dioxin exposure in simple terrain, reinforcing the results of our case-control study. However, a more advanced atmospheric diffusion model should have been used for refined assessment in complex terrain.

International audience; BACKGROUND: In 1998, the French Ministry of Environment revealed that of 71 French municipal solid waste incinerators processing more than 6 metric tons of material per hour, dioxin emission from 15 of them was above the 10 ng international toxic equivalency factor/m3 (including Besançon, emitting 16.3 ng international toxic equivalency factor/m3) which is substantially higher than the 0.1 international toxic equivalency factor/m3 prescribed by a European directive of 1994. In 2000, a macrospatial epidemiological study undertaken in the administrative district of Doubs, identified two significant clusters of soft-tissue sarcoma and non Hodgkin lymphoma in the vicinity of the municipal solid waste incinerator of Besançon. This microspatial study (at the Besançon city scale), was designed to test the association between the exposure to dioxins emitted by the municipal solid waste incinerator of Besançon and the risk of soft-tissue sarcoma. METHODS: Ground-level concentrations of dioxin were modeled with a dispersion model (Air Pollution Control 3 software). Four increasing zones of exposure were defined. For each case of soft tissue sarcoma, ten controls were randomly selected from the 1990 census database and matched for gender and age. A geographic information system allowed the attribution of a dioxin concentration category to cases and controls, according to their place of residence. RESULTS: Thirty-seven cases of soft tissue sarcoma were identified by the Doubs cancer registry between 1980 and 1995, corresponding to a standardized incidence (French population) of 2.44 per 100,000 inhabitants. Compared with the least exposed zone, the risk of developing a soft tissue sarcoma was not significantly increased for people living in the more exposed zones. CONCLUSION: Before definitely concluding that there is no relationship between the exposure to dioxin released by a solid waste incinerator and soft tissue sarcoma, a nationwide investigation based on other registries should be conducted.

Background Dioxin emissions from municipal solid waste incinerators are one of the major sources of dioxins and therefore are an exposure source of public concern. There is growing epidemiologic evidence of an increased risk for non-Hodgkin's lymphoma (NHL) in the vicinity of some municipal solid waste incinerators with high dioxin emission levels. The purpose of this study was to examine this association on a larger population scale. Methods The study area consisted of four French administrative departments, comprising a total of 2270 block groups. NHL cases that had been diagnosed during the period 1990–1999, and were aged 15 years and over, were considered. Each case was assigned a block group by residential address geocoding. Atmospheric Dispersion Model System software was used to estimate immissions in the surroundings of 13 incinerators which operated in the study area. Then, cumulative ground-level dioxin concentrations were calculated for each block group. Poisson multiple regression models, incorporating penalized regression splines to control for covariates and dealing with Poisson overdispersion, were used. Five confounding factors were considered: population density, urbanisation, socio-economic level, airborne traffic pollution, and industrial pollution. Results A total of 3974 NHL incident cases was observed (2147 among males, and 1827 among females) during the 1990–1999 time period. A statistically significant relationship was found at the block group level between risk for NHL and dioxin exposure, with a relative risk (RR) of 1.120 (95% confidence interval [CI] 1.002 – 1.251) for persons living in highly exposed census blocks compared to those living in slightly exposed block groups. Population density appeared positively linked both to risk for NHL and dioxin exposure. Subgroup multivariate analyses per gender yielded a significant RR for females only (RR = 1.178, 95% CI 1.013 – 1.369). Conclusion This study, in line with previous results obtained in the vicinity of the incinerator located in Besançon (France), adds further evidence to the link between NHL incidence and exposure to dioxins emitted by municipal solid waste incinerators. However, the findings of this study cannot be extrapolated to current incinerators, which emit lower amounts of pollutants.