Comparison among the number of cigarettes smoked estimated through wastewater analysis and epidemiological surveys in the population investigated
| Cities investigated | Wastewater analysis | Epidemiological survey data | Difference in the number of cigarettes smoked | |||||
|---|---|---|---|---|---|---|---|---|
| Population (>14 years) served by the STP* | Estimated NICabs (g/day; mean±SD)† | Number of cigarettes smoked‡ | Prevalence of smokers (% of population ≥15 years) | Number of smokers§ | Number of cigarettes smoked¶ | Number of cigarettes (survey data-wastewater analysis results) | Percentage (survey data-wastewater analysis results) | |
| Northern Italy | ||||||||
| Milan | 960 300 | 2121±237 | 1 696 800 | 19.6 | 188 219 | 2 409 201 | +712 401 | +30 |
| Como | 79 926 | 241±51 | 192 800 | 19.6 | 15 665 | 200 518 | +7718 | +4 |
| Bologna | 470 640 | 1360±127 | 1 087 726 | 19.6 | 92 245 | 1 180 742 | +93 016 | +8 |
| Turin | 1 201 490 | 4756±393 | 3 804 828 | 19.6 | 235 492 | 3 014 298 | −790 530 | −26 |
| Mean | 1 695 538 | 1 701 190 | +5651 | +0.3 | ||||
| Central Italy | ||||||||
| Rome | 1 107 699 | 3734±1779 | 2 987 243 | 19 | 210 463 | 3 114 850 | +127 606 | +4 |
| Southern Italy | ||||||||
| Naples | 549 250 | 2492±266 | 1 993 948 | 23.3 | 127 975 | 1 714 868 | −279 080 | −16 |
| Bari | 296 922 | 1076±43 | 860 912 | 23.3 | 69 183 | 927 050 | +66 137 | +7 |
| Palermo | 223 254 | 958±75 | 766 416 | 23.3 | 52 018 | 697 044 | −69 372 | −10 |
| Mean | 1 207 092 | 1 112 987 | −94 105 | −8 | ||||
Bold denotes the mean values.
*The total population (served by the STP) was corrected by the percentage of people <14 years.19
†Mean and SD are calculated from the daily mass loads obtained for each city. Sampling campaigns were: 18 days in Milan and 7 days in all the other cities.
‡Calculated using the mean content of nicotine absorbed from one cigarette (1.25 mg).1
§Calculated from prevalence data considering the population served by the STPs investigated.
¶Calculated considering the average number of cigarettes smoked per day (12.8±6.8 in the North of Italy, 14.8±6.7 in the Center and 13.4±7.7 in the South).18
NICabs, nicotine absorbed; STP, sewage treatment plant.