dividual exposure. Indeed a higher exposure is expected for white collar workers and retirees whan compared to blue collar workers but an opposite effect is observed. This may be explained by the fact that the reference modality for this variable is a very heterogeneous modality also comprising managers and self-employed persons (farmers and craftsmen). Another explanation could be that white collars workers have a higher propensity to eat out in restaurants whereas outside the home consumption is not included in the model. 

Table 2 around here, see page 21 Table 3 around here, see page 22 Table 4 around here, see page 22 

Likelihood ratio tests are implemented to test the structure of the final model. First, the dependence of individual exposures to methylmercury within a household is tested. The null hypothesis ρ = 0 (cf. equation (2.5)) is rejected (null Pval) which confirms that individuals within the same household have correlated exposures. Then, we test if the function f is the same for both genders. The null hypothesis f$_{M}$ = f$_{F}$ is rejected (null Pval) but the null hypothesis σ 2 u$_{M}$ = σ 2 u$_{F}$ is accepted. This means that individual exposure differs with gender but both functions need the same amount of smoothing. 

## 3.2 The cumulative and the long term individual exposure 

The cumulative individual exposure S$_{i,h,t}$ is calculated from the estimated individual weekly intakes according to equation (1.1) and the resulting values for t > 35 are compared to the reference cumulative exposure defined by (1.3). Figure 1 shows the cumulative individual exposure over the 53 weeks of the year 2001 for different individuals. Only certain percentiles of the distribution of the individual cumulative exposures of the last week are displayed. For example, the curve Pmax represents the cumulative exposure of an individual whose last week’s cumulative exposure is the highest. This is the cumulative exposure of a girl who turned one year old during the 30th week of 2001, lives in Paris or its suburbs in a well to do household. 

Very few individuals have a cumulative individual exposure above the reference long term ex- posure. We estimate that only 0 . 186% of individuals are deemed at risk. This risk index should be 

